Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Diagnosis of Nonmelanoma Skin Cancer/Keratinocyte Carcinoma: A Review of Diagnostic Accuracy of Nonmelanoma Skin Cancer Diagnostic Tests and Technologies METTE MOGENSEN, MD, AND GREGOR B. E. JEMEC, MD, DMSC BACKGROUND Nonmelanoma skin cancer (NMSC) is the most prevalent cancer in the light-skinned population. Noninvasive treatment is increasingly used for NMSC patients with superficial lesions, making the development of noninvasive diagnostic technologies highly relevant. OBJECTIVE The scope of this review is to present data on the current state-of-the-art diagnostic methods for keratinocyte carcinoma: basal cell carcinoma, squamous cell carcinoma, and actinic keratosis. METHODS AND MATERIALS MEDLINE, BIOSIS, and EMBASE searches on NMSC and physical and clinical examination, biopsy, molecular marker, ultrasonography, Doppler, optical coherence tomography, dermoscopy, spectroscopy, fluorescence imaging, confocal microscopy, positron emission tomography, computed tomography, magnetic resonance imaging, terahertz imaging, electrical impedance and sensitivity, specificity, and diagnostic accuracy. RESULTS State-of-the-art diagnostic research has been limited in this field, but encouraging results from the reviewed diagnostic trials have suggested a high diagnostic accuracy for many of the technologies. Most of the studies, however, were pilot or small studies and the results would need to be validated in larger trials. CONCLUSIONS Some of these new imaging technologies have the capability of providing new, threedimensional in vivo, in situ understanding of NMSC development over time. Some of the new technologies described here have the potential to make it from the bench to the clinic. Mette Mogensen, MD, and Gregor B. E. Jemec, MD, DMSc have indicated no significant interest with commercial supporters. N onmelanoma skin cancer (NMSC) is the most prevalent cancer in the light-skinned population, and the critical factor in assessment of patient prognosis in skin cancer is early diagnosis.1 Serious morbidity in NMSC is often the result of misdiagnosis or underestimation of the biologic potential of the primary tumor. All diagnostic tests can be accredited with precision and accuracy. Precision, also known as reliability, reproducibility, or repeatability, refers to agreement of the test. If the diagnostic test is performed multiple times on the same subject with the same result, the test is precise. Accuracy describes whether the diagnostic test yields a correct or incorrect answer by correlating the test result with the truth. Thus the accuracy of a test tells us how efficient it is in arriving at the correct diagnosis. The accuracy of a diagnostic test is usually reported in terms of its sensitivity, specificity, and predictive values. The truth, the correct diagnosis, cannot always unequivocally be reached, and for that reason, a ‘‘gold standard’’ or reference standard is chosen to represent the truth. For skin cancer a biopsy specimen obtained for histopathologic examination to diagnose skin cancer is considered the reference standard. Biopsy may be a time-consuming, expensive, and sometimes a mutilating and painful experience to the patient, especially because only approximately Both authors are affiliated with the Department of Dermatology, University of Copenhagen, Roskilde Hospital, Roskilde, Denmark & 2007 by the American Society for Dermatologic Surgery, Inc. Published by Blackwell Publishing ISSN: 1076-0512 Dermatol Surg 2007;33:1158–1174 DOI: 10.1111/j.1524-4725.2007.33251.x 1158 MOGENSEN AND JEMEC 3% of presumed benign lesions are actually malignant.2 Furthermore, whereas treatment has hitherto been almost synonymous with surgery, new noninvasive treatment strategies call for noninvasive diagnostics. To assist clinical diagnosis of NMSC and malignant melanoma (MM), an extensive assortment of diagnostic technologies and tests have been developed.3 The scope of this review is to present available data on the diagnostic accuracy of the different diagnostic methods. NMSC refers mainly to basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and premalignant actinic keratosis (AK). Accurate diagnostic test assessment involves four phases4: Determining the normal range of values for a diagnostic test through observational studies in healthy people (1), diagnostic accuracy assessment through case-control studies (2), assessment of clinical consequences of introducing a diagnostic test through randomized trials (3), and determining the effects of introducing a new diagnostic test into clinical practice by surveillance in large cohort studies (4).5 Materials We have searched for clinical, human studies on the diagnostic accuracy of the following NMSC diagnostic tests and techniques: clinical and physical examination; biopsy techniques; histopathology and molecular markers; high-frequency ultrasonography (HFUS); Doppler sonography; dermoscopy, dermatoscopy, epiluminescence microscopy, incident light microscopy, and skin surface microscopy; optical coherence tomography (OCT); confocal microscopy (CM); near infrared and Raman spectroscopy; fluorescence imaging/spectroscopy; terahertz imaging; electrical impedance; positron emission tomography (PET), computed tomography (CT); and magnetic resonance imaging (MR, MRI). Studies of NMSC diagnosis have been included in this review according to the search protocol of the review. Our interest has been to sample data on diagnostic accuracy in NMSC diagnostics. If sensitivity and specificity values have not been calculated, we have calculated values whenever the data were available. Methods MEDLINE, BIOSIS, and EMBASE searches on medical subject headings (MeSH) or similar terms: skin, skin appendages, dermis, cutis, epidermis, integumentum, skin neoplasms, skin tumor and/or tumor, BCC, SCC, Bowen’s disease, AK and/or solar keratosis, keratinocyte carcinoma and physical and clinical examination, biopsy, molecular marker, ultrasonography, Doppler, OCT, dermoscopy, dermatoscopy, epiluminescence microscopy and/or incident light microscopy, spectroscopy, fluorescence imaging, spectrophotometry, colorimetry, confocal microscopy, PET, positron emission tomography, CT, computed tomography, MR, MRI, magnetic resonance imaging, terahertz imaging, electrical impedance and diagnosis, sensitivity and specificity, and diagnostic accuracy. Articles and abstracts have also been retrieved from Web searches on Google Scholar, Ixquick, Scirus, and reference lists of identified studies. Only studies on diagnosis of NMSC have been selected for this review. Only articles published after 1990 have been included. Articles were restricted to those involving humans. Results Clinical and Physical Examination Despite being the most accessible and used test, precision and accuracy of the clinical examination are often not known. The precision in clinical examination can be described as intra- and interobserver differences. Precision estimates must be generated in a blinded fashion; this is feasible in interobserver observations, but as lesions change over time intraobserver differences must be estimated from evaluation of pictures of skin lesions assessed at two different times.6,7 Physical examination for NMSC can be performed by an expert, by a general practitioner or by the patient. Results from the 33:10:OCTOBER 2007 1159 DIAGNOSTIC ACCURACY OF NONMELANOMA SKIN CANCER DIAGNOSTIC TESTS selected studies2,6–14 are presented in Table 1. The false-negative diagnostic rates as well as the falsepositive rates cannot be ignored as it was demonstrated in a study where 3% of lesions assessed as benign proved malignant and 40% of suspected malignancies were benign.2 In the reviewed studies the overall sensitivity for clinical diagnosis of NMSC is 56% to 90%, and specificity 75% to 90%, with highest values for BCC diagnosis. In studies where positive predictive value (PPV) is mentioned, it must be taken into account that PPV is prevalence-dependent; a study conducted in a high prevalence setting would tend to increase PPV. Patients themselves may also be involved in the diagnosis of cancer. When patients with nevi and/or melanocytic lesions assessed new and changing moles by performing a skin self-examination, the accuracy was significantly higher with the aid of a baseline digital photography of the skin.15 No similar studies have been performed with NMSC. Biopsy Techniques Shave and punch biopsy have been compared in a study including 86 biopsy specimens and subsequent total excision of the tumor.16 Punch biopsy was accurate in determining BCC in 81% of cases, and shave biopsy correctly identified 76%. In a systematic review of exfoliative cytology in diagnosis of BCC, a meta-analysis showed the pooled sensitivity to be 97% [95% confidence interval (CI), 94%–99%] and specificity 86% (95% CI, 80%–91%);17,18 however, cytology does not give any information about subtype and none about tumor borders. Histopathology and Molecular Markers Histopathology is a subjective assessment by a dermatopathologist, i.e., data acquisition guided by classification standards and pattern recognition by the human brain. Ideally histopathologic classification of NMSC should be able to identify subtypes that correlate with clinical behavior and treatment 1160 D E R M AT O L O G I C S U R G E RY requirements. In addition, the classification should be easy to use and reproducible. Determining diagnostic accuracy of the reference standard itself is hampered by the fact that there are several classification systems for NMSC.19,20 Difficulties confront pathologists reporting BCCs: Many BCCs have more than one growth pattern, and published data have varied with regard to number necessary to designate the presence of a specific subtype. Furthermore, the accuracy of reporting different subtypes has not been extensively investigated.19 In general, interobserver differences cannot be neglected as a potential source of error, with potential clinical consequences for the patient, but also diagnostic researchwise, because all other skin cancer diagnostic techniques must be compared to histopathology, the reference standard. The interobserver differences in this review ranged from 1.2% to 7%. In Table 2 results from the reviewed studies are presented.21–26 A current research goal is to define skin cancer by its phenotype in terms of molecular abnormalities as a reference standard for NMSC diagnosis.19,20,27–30 To date a molecular marker with a high diagnostic accuracy in NMSC diagnosis has not been identified. HFUS and Doppler Sonography The principle in HFUS is the emission of a pulsed ultrasound (US) from a transducer and registration of the intensity of the echo backscattered from the tissue. The amplitude of the curve reproduces the intensity and time delay of the returning US and is called A-scan. A B-scan is created when the transducer is moved laterally creating a two-dimensional image. Penetration depth and resolution of US is inversely related to the frequency, which makes HFUS suitable in dermatology. Axial resolution at 20 MHz is 50 mm and lateral resolution is 350 mm. The sonographic characteristics of skin tumors have been widely investigated during the past decades31–51 (Table 3). By means of HFUS, skin tumors generally appear as a homogeneously echo-poor area in comparison to the surrounding echo-rich dermis. Because all skin tumors appear echo-poor, HFUS alone is not 6 Plastic surgeons Har-Shai et al., 200111 Whited et al., 1997110 835 lesions in 778 2582 NMSC lesions excised from 1223 Dermatologists 493 NMSC patients and family practitioners (FP) Primary care phy- 190 NMSC sicians (PCP) patients and dermatologists Plastic surgeons Morrison et al., 20019 Does history influence the clinical diagnosis? Question 53 patients with 143 Observer agreement NMSC lesions Choose between a Observer agreement diagnosis of either AK or SCC in 15 slides 141 patients with Effect of additional data BCC lesions 50 NMSC patients Number of participants Diagnostic accuracy Diagnostic accuracy Diagnostic accuracy Diagnostic accuracy Dermatologists complete a questionnaire before biopsy, confidence was plotted level 1–3 Dermatologist di- 102 lesions in 70 re- Diagnostic accuracy agnosis was nal transplant pacompared to tients histopathology Plastic surgeons 2058 lesions in 809 Diagnostic accuracy NMSC patients referred for tumor excision Dermatologists blinded to the patient history Two dermatologists 77 pathologists Group studied Ek et al., 200512 Hallock and Lutz, 19982 Cooper and Wojnarowska, 200214 Schwartzberg et al., 20058 Davis et al., 200513 Leffell et al., 199310 Whited et al., 1995 Authors, year TABLE 1. Clinical Diagnosis Sensitivity of the PCPs was 57% (95% CI, 44%–68%) and specificity 88% (95% CI, 81%–93%). FPs diagnosed 22% of skin cancer before biopsy, dermatologists diagnosed 87% correctly. Sensitivity 91% and a PPV of 71%. Three-fourths of benign lesions were identified (sensitivity 93% and specificity 86%). Only 60% of malignant lesions were identified (sensitivity 73% and specificity 90%). 3% of presumed benign lesions were malignant. BCC and SCC was diagnosed with a sensitivity of 89% and 56% and a PPV of 65% (p = .001). Sensitivity was 90.5% (SCC) and 66.6% (BCC). Specificity was 75.3% (SCC) and 85.6% (BCC). PPV was 80% when additional data was presented. ICC was 0.96 for dermatopathologists and anatomic pathologists and 0.65 for fellows.y Kappa 0.78 in AK and 0.38 in SCC. Kappa values 0.04 (blinded) and 0.76 (with history). Result MOGENSEN AND JEMEC 33:10:OCTOBER 2007 1161 1162 Oliveria et al., 200415 D E R M AT O L O G I C S U R G E RY The kappa statistics is a measure of the agreement level beyond what might be expected by chance alone. The kappa values vary from 1 (perfect disagreement) to 1 1 (perfect agreement). y Intraclass correlation coefficient (ICC) is an estimate of the interobserver reliability by two-way analysis of variance. Standard criteria for ICC are 0.40 = poor; 0.40–0.59 = fair; 0.60–0.74 = good; 0.75–1.00 = excellent correlation between observers. AK, actinic keratosis; BCC, basal cell carcinoma; NMSC, nonmelanoma skin cancer; PPV, positive predictive value; SCC, squamous cell carcinoma. 50 patients with dysplastic nevi Diagnostic accuracy GPs diagnosed SCC in 70, dermatologists in 24. 53 suspected SCCs were biopsied; 13 of these were confirmed SCC by pathologists. The accuracy of self-examination was significantly higher (p = .001) with the aid of digital photography. Sensitivity without photo was 60% and specificity 96% compared to sensitivity with photo was 72% and specificity 98%. Diagnostic accuracy GPs, dermatologists, and pathologists Patients Westbrook et al., 2006111 283 NMSC cases Result Group studied Authors, year TABLE 1. Continued Number of participants Question DIAGNOSTIC ACCURACY OF NONMELANOMA SKIN CANCER DIAGNOSTIC TESTS suitable for differential diagnosis.52,53 Overestimation of tumor thickness appears to be a general problem because fibrosis and inflammation generally have the same echogenecity as NMSC. Skin tumor vascularization studies using Doppler techniques are presented in the Table 3 as well. Laser Doppler (LD) devices send a monochromatic laser beam toward the target and collect the reflected radiation. According to the Doppler effect, the change in wavelength of the reflected radiation is a function of the targeted object’s relative velocity. The velocity of the object can thus be calculated by measuring the change in wavelength of the reflected laser light. LD can be configured to act as flow meters. In short HFUS in NMSC diagnosis is to some extent capable of revealing the three-dimensional size, margins, and relation to adjacent vessels of a suspicious skin lesion. Information on quality (such as solid, cystic, or combined) and information about the inner structure (homogeneous, inhomogeneous, hypo- or hyperechoic, calcification, or necrosis) can be obtained54 (Figure 1). Dermoscopy, Dermatoscopy, Epiluminescence Microscopy, Incident Light Microscopy, and Skin Surface Microscopy In dermoscopy the lesion is examined with a 10 to 100 magnification lens placed directly against skin to which immersion oil has been applied to remove scatter of light at the air–skin boundary. Dermoscopy has had the largest clinical impact regarding new skin cancer diagnostic technologies in the diagnosis of pigmented skin lesions, but it has also been used in NMSC. Dermoscopy of NMSC is still at its infancy because consensus regarding diagnostic criteria has not been established yet. Diagnostic accuracy regarding vessels characteristics in BCC and Bowen’s disease, however, seems quite promising, and sensitivity for BCC diagnosis ranges from 87% to 96%, and specificity from 72% to 92% (Table 4). Dermoscopy and spectroscopy devices, when linked to a video microscope for computer analysis, have MOGENSEN AND JEMEC TABLE 2. Histopathology and Molecular Markers Authors, year Group studied Lind et al., 199521 Two pathologists Olhoffer et al., 200222 Brochez et al., 200223 Dermatopathologists 336 cases and pathologists Trotter and Bruecks, 200326 Renshaw et al., 2002112 Kamiya et al., 200324 Biesterfeld and Josef, 200225 Number of cases 2694 slides Question Results Interobserver differences Thirty-two major errors were found, involving 1.2% of cases reviewed. Errors were divided into four types: (1) major: errors in diagnosis that could directly affect patient care; (2) diagnostic discrepancies: errors in diagnosis that should not affect patient care; (3) minor: correct diagnosis rendered, but report correction required to add supportive information; (4) clerical: typographical and grammatical errors. Discordance in 5.7% of cases. New management in 18 of 19 severe cases. Overall sensitivity was 87% (range, 55%–100%) and specificity 94% (range, 83%–100%). Interobserver differences 20 pathologists 48 slides Interobserver diagnosing differences pigmented skin lesions and NMSC Two pathologists Blinded Interobserver Agreement was found in more review of 592 histo- differences than 93% of cases. pathology slides 77 pathologists (both 15 SCC and Interobserver Mean ICC was 0.97 for all patholdermato- and AK slides differences ogists. Agreement was above anatomic) 70% for 11 of 15 slides. Performing reverse 26 lymph nodes; 10 Molecular mark- This method showed a detection transcriptase–polyhad histologically er: micrometassensitivity of one tumor cell in merase chain reac- proven metastasis, tasis of SCC in 106 lymphocytes. tion (RT-PCR) to and 16 had none lymph nodes amplify keratin19 MIB-1 immuno49 keratoacanthomas Molecular mark- If specificity 85% is required senhistometry for the and 48 SCCs er: proliferation sitivity decreases to 56%. MIB-1 differential diagnomarker MIB-1 is currently of limited value in sis between KA and SCC diagnosis. SCC Intraclass correlation coefficient (ICC) is an estimate of the interobserver reliability by two-way analysis of variance. Standard criteria for ICC are 0.40 = poor; 0.40–0.59 = fair; 0.60–0.74 = good; 0.75–1.00 = excellent correlation between observers. AK, actinic keratosis; NMSC, nonmelanoma skin cancer; SCC, squamous cell carcinoma. been named ‘‘mole scanners.’’3 One pilot study on NMSC diagnosis with computerized dermoscopy combined with a two-dimensional in vivo reflectance spectrophotometer included a few BCC and also MM patients.55 Nodular BCC showed a characteristic concentration of perilesional blood vessels combined with slight central fibrosis. Pigmented BCC did not show the erosion of dermal collagens specific for MM. Dermoscopic features of BCC are arborizing vessels defined as stem vessels with a large diameter, branching irregularly into the finest terminal capillaries. Diameter of the vessels can be up to 0.2 mm, branching irregularly into capillaries of 10 mm.56 Gray-brown lumps, often ovoid in shape, and amber-colored crusts are other dermoscopy features in BCC (Figure 2). In Bowen’s disease, dermoscopic 33:10:OCTOBER 2007 1163 DIAGNOSTIC ACCURACY OF NONMELANOMA SKIN CANCER DIAGNOSTIC TESTS TABLE 3. High-Frequency Ultrasonography Authors, year Number and pathology of patients Question asked Results 181 patients with BCC before Thickness of the BCC thickness predicts outcome 1 year Moore and and after photodynamic lesions after photodynamic therapy with dAllan, 200333 therapy treatment aminolevulinic acid. 33 patients with SCC HFUS diagnosis of In SCC of the penis, HFUS provides diagLont et al., SCC of the penis nostic value in staging the disease. PPV 2003113,114 compared to MRI for corpus cavernosum infiltration, 67% (HFUS) and 75% (MRI). 16 BCC lesions and Laser Doppler perfu- Tumor perfusion values higher than surStucker et al., 27 MM sion imaging rounding skin. BCC perfusion values 1999115 similar in the tumor area as opposed to MM, where perfusion was higher in the tumor center. 81 clinically malignant Laser Doppler perfu- Sensitivity 0.75 and specificity 0.79 if Schroder tumors sion imaging three to five vessels were visible in the et al., 2001116 study with and tumor, and sensitivity 0.58 and speciwithout contrast ficity 0.88 if a parameter called ‘‘percentage vessel area’’ exceeded 5%. 19 benign, 32 BCC, and Power Doppler Specificity of 63% and sensitivity 88% in Karaman 15 SCC (Doppler indediagnosis based on vascular patterns et al., 200132 pendent of angle) alone in the lesions. BCC, basal cell carcinoma; HFUS, high-frequency ultrasound; MM, malignant melanoma; MRI, magnetic resonance imaging; PPV, positive predictive value; SCC, squamous cell carcinoma. features are glomerular vessels (90%) and scaly surface (90%).57 Glomerular vessels are dotted vessels often distributed in clusters mimicking the glomerular apparatus of the kidney. Compressing the blood vessels renders them invisible. Magnification by 30 times or more must be applied to visualize vessels down to 10 mm.58 OCT OCT is a novel, noninvasive optical imaging technology. It can provide cross-sectional tomographic images of tissue pathology in situ and in real time. OCT is analog to B-mode US pulse-echo imaging with an optical rather than acoustical reflectivity being measured. In OCT, linear characteristics as scattering, absorption, birefringence, and refractive index are measured to produce images with micrometer resolution.59 When birefringence characteristics of the tissue are mapped in OCT images, it is referred to as polarization sensitivity (PS) OCT. OCT images can also be enhanced by Doppler function. 1164 D E R M AT O L O G I C S U R G E RY OCT provides cross-sectional images of structures below the tissue surface in analogy to histopathology.60,61 NMSC and MM has been investigated with OCT with quite promising results.62–67 Pilot studies have suggested that OCT can be used clinically in diagnosing NMSC.62,63,65,67,68 In a study of 20 BCC lesions, there was an excellent match of histologic features seen on light microscopy with OCT images of superficial, nodular, micronodular, and infiltrative BCCs. The actual predictive value of OCT in BCC patients could not be calculated from this study. In another study of three patients with superficial BCC and three patients with cutaneous MM, OCT images were compared with histology. The size, allocation, and form of BCC nests seemed to be similar to those in histologic images.69 In a study of nine patients with 12 BCC lesions, some lesions were distinct in OCT images and BCC subtypes as superficial and nodular could be identified in OCT images.70 Interestingly scar tissue could be distinguished from BCC with PS-OCT. Therefore, PS-OCT may have MOGENSEN AND JEMEC Figure 1. HFUS and Doppler images of BCC lesion on the nose. (A) Photo of the BCC lesion. (B) 18-MHz real-time HFUS image of BCC lesion in (A). (C) Doppler image of lesion in (A); vasculature is marked in red and blue. (D) Histopathology slide HE stain from the lesion (A) showing BCC; original magnification, 20. Images by courtesy of Dr Ximena Wortsman, Chile. additional advantages as BCC differ in content of birefringent collagens from normal skin. In a study of two patients with invasive BCC, PS-OCT was used to discriminate tumors from normal skin. In normal skin, a bright band of birefringence signal is seen at middepth of the PS-OCT image, corresponding to the upper reticular dermis. In PS-OCT images of invasive BCC, there was a dramatic alteration in the birefringence signal, it almost disappeared in the ulcerative, invasive BCC and showed a haphazard distribution in the other invasive BCC lesion (see also Figure 2). Furthermore, a gradual transition from normal-appearing tissue to tumor tissue could be detected by PS-OCT at the BCC borders, indicating an ability of PS-OCT to delineate tumor borders71 (Figure 3). A study compared OCT and HFUS in diagnosis of eyelid tumors. Examination of 38 patients (BCC 4/38, AK 1/38, and other benign and malignant tumors) showed that OCT was superior in detecting cystic lesions, but due to low penetration of the OCT system in the skin, tumor margins could not be determined.72 CM Reflectance CM or confocal scanning laser microscopy has the highest resolution of all optical techniques used in NMSC diagnosis research.73 Current CM systems have an axial resolution of 1 to 5 mm and a lateral resolution of 0.5 to 1 mm. The penetration depth maximum is 300 mm. CM uses a point source light to illuminate a small spot within a tissue. The pinhole minimizes out-of-focus light reaching the detector, and only confocal light is detected. For in vivo imaging, a plastic cap filled with water must be adapted to the skin. CM has proved a potentially valuable diagnostic aid in BCC and SCC diagnosis, both ex vivo and in vivo74,75 (Table 5). Characteristic CM features of NMSC are, in BCCs, abundant blood vessels juxtaposed to BCC cells, sometimes in 33:10:OCTOBER 2007 1165 DIAGNOSTIC ACCURACY OF NONMELANOMA SKIN CANCER DIAGNOSTIC TESTS TABLE 4. Dermoscopy Authors, year Number and pathology of patients Question asked 21 SCCs in situ (Bowen’s disease) Characteristic dermoscopy features Results Glomerular vessels with a patchy distribution and scaly surface was found in 90% of all lesions. Characteristic Arborizing vessels are detected in Menzies, 2002118 71 pigmented BCC lesions dermoscopy 52%, sensitivity was 93%, and features specificity was 89%–92%. Internet study regarding di- Sensitivity for BCC was 86.7% (95% Zalaudek et al., 165 lesions (including 20 BCCs, otherwise mostly agnostic accuracy, a three- CI, 76.9%–92.7%) and specificity 2006119 pigmented lesions, 150 point checklist (asymme71.9% (95% CI, 56.6%–83.3%). dermatologists and other try, atypical network, bluedoctors white structures) 531 lesions (117 BCCs) Diagnostic features: vascular Arborizing vessels were seen in Argenziano from 517 patients structures 82% of BCCs, with a PPV of 94% et al., 200456 (po.001) SCCs in situ: 13 of 16 lesions showed glomerular vessels, PPV 62% Diagnostic features: vascular Sensitivity 96%, specificity 91%. Kreusch, 200258 BCC patients, number not retrieved structures 7 BCC patients, Diagnostic features: vascular Microvessel area fractions were inOtis et al., 12 patients structures with capillaroscreased 4.9-fold in BCC and 2.52004;120 Newell et al., copy fold in AK compared to normal 2003121 skin. 111 skin samples Blood vessels counted after Significant difference between the Chin et al., (including immunohistochemistry groups and also between BCCs 2003122 20 SCCs, 50 BCCs) and SCCs. Zalaudek et al., 2004, 200557,117 AK, actinic keratosis; BCC, basal cell carcinoma; PPV, positive predictive value; SCC, squamous cell carcinoma. tightly packed nests, and rolling of leukocytes and lymphocytes along the endothelial lining. BCC cells appeared to be oval, elongated with a prominent, monomorphic polarized nucleus. Tumor cells had a high refractive index with dark-appearing nuclei, and the cytoplasm appeared bright.76,77 In SCC, features are irregular epithelial mass with a variable proportion of normal and atypical keratinocytes, along with areas of anaplasia; in AKs, CM revealed hyperkeratosis, lower epidermal nuclear enlargement, and pleomorphism.74 Some features seen in CM images (e.g., uniform polarization of BCC nuclei, margination and rolling of leukocytes) are morphologic features not recognized in BCC histologypathology.76,77 In Mohs micrographic surgery (MMS), CM may have a role in analyzing untreated fresh biopsy specimens. Fluorescence fiber-optic CM in vivo is a novel technique, where fluorophore distribution in the skin may illustrate morphologic 1166 D E R M AT O L O G I C S U R G E RY changes in the epidermis. An application for fluorescence CM is the ability to image fluorescent markers that target specific subcellular molecules including proteins and therefore to monitor specific pathologic and immune processes over time.78 Near Infrared, Diffuse Reflectance, and Raman Spectroscopy Light that penetrates the skin surface is variably absorbed by different skin components termed chromophores. The skin components, which subsequently emit radiation, are termed fluorophores. Optical measurements of the skin can therefore be based on the interactions of nonionizing electromagnetic radiation and the skin.73 The absorbed energy may be dissipated as heat (tissue absorption), reemitted as electromagnetic radiation of lower energy with a longer wavelength (fluorescence), or even MOGENSEN AND JEMEC Figure 2. Dermoscopy image from a BCC lesion (A) and the corresponding clinical photo (B). The dermoscopy image visualizes the arborizing vessel in the upper right section of the lesion. Images courtesy of Prof. Kaare Weismann, MD, DMSc, Horsholm Dermatology, Denmark. reemitted as radiation of higher energy (Raman scattering), the latter being the least probable event. A spectroscope separates the returned light into individual wavelengths and assesses it. Raman spectroscopy provides molecular information of a sample irradiated with laser light as a small fraction is shifted in frequency (Raman effect). Several studies have described a characteristic Raman spectra in NMSC.79–88 A sensitivity of 97% and specificity of 98% were found in a study of 48 BCCs. In vivo Raman spectroscopy is possible but the precision of the spectra is low. Two ex vivo studies found distinct Raman band differences between BCC and normal skin. Ten samples of BCC suggested this from direct observations of spectral differences, after reducing endogenous autofluorescence by a confocal device, and the two groups were significantly different from each other.89 In an in vitro study of 15 BCCs, Raman pseudo-color maps were compared to skin biopsies. Pseudo-color maps assign areas with similar spectra with the same color and are generated by multivariate statistical analysis and clustering analysis of spectra. A prediction model could classify new tissue samples from BCC lesions from their Raman spectra with a sensitivity of 100% and specificity of 93%.82 Another study suggested that neural network analysis of near-infrared Fourier transform Raman spectra may show some potential for ex vivo NMSC diagnosis79 An in vivo study of 195 patients with a variety of malignant and benign skin lesions (33 AKs, 32 BCCs) showed promising results for the screening of skin lesions with near infrared spectroscopy. Spectra were compared to histopathology in all lesions; univariate statistics showed significant differences between spectra and healthy skin (normal skin vs. AKs, BCCs, dysplastic nevi, lentigines, banal nevi, and seborrheic keratosis) and also between the spectra themselves. Significant differences, however, are not always diagnostic differences. A pattern recognition technique was applied and successfully discriminated lesions with accuracy higher than 80%.81 Fluorescence Imaging Specific autofluorescence emitted from malignant tissue upon radiation with a laser, xenon light, or halogen lamp has been used to distinguish normal tissue from cancerous tissue in the head and neck region.90 Fluorescence imaging is an attractive potential diagnostic technique for skin tumor demarcation. In a study of 21 patients with 80 BCCs, the fluorescence intensity from BCCs was significantly lower than surrounding, normal skin91 In a study of 33:10:OCTOBER 2007 1167 DIAGNOSTIC ACCURACY OF NONMELANOMA SKIN CANCER DIAGNOSTIC TESTS Figure 3. OCT images of BCC. (A) Nodular BCC lesion on the back. (B) PS-OCT image of (A); notice the black band in the upper part of the lesion, corresponding to lack of birefringence. The white birefringence band is clearly seen in (E). (C) OCT image of the lesion in (A); notice the disruption of the layered skin structure. (D) OCT image of normal adjacent skin. (E) The corresponding PS-OCT image. OCT Images from Department of Dermatology, Roskilde Hospital, recorded with an OCT system developed by Risoe National Laboratory. Images provided by Dr Mette Mogensen. 18 patients with 25 NMSC lesions (20 BCCs and 5 SCCs), a fiber-optic–based fluorimeter collected spectral data in vivo and microscopic fluorescence ex vivo.92 The fluorescence of tryptophan moieties in BCC was 2.9 7 1.9 SD, and for SCC 2 7 0.9 SD times larger. A marked loss of fluorescence in the middle of the tumor region was noticed in 78% of the NMSC lesions due to a decrease in collagen and elastin cross-links. Another study of 49 patients (BCC, SCC, AK, and normal skin) compared diagnostic accuracy in laser-induced fluorescence spectroscopy for skin types I to III (Pathak) to determine the skin colors effect on the results.84 Melanin absorbs fluorescence strongly. Typically normal skin 1168 D E R M AT O L O G I C S U R G E RY exhibited stronger fluorescence emission than BCC and SCC. The accuracy of classifying NMSC was higher (93%) in Type I skin. It has also been suggested that due to the large variation in fluorescence intensities developing, an algorithm for NMSC is difficult.93 Bispectral fluorescence imaging combines skin autofluorescence with d-aminolevulinic acid (ALA) fluorescence. The agreement between bispectral fluorescence images and the histopathologic tumor boundary of ill-defined BCC in 12 patients with an aggressive BCC undergoing MMS was examined.86 Only 5 patients had good correlation between histopathology and bispectral images of the tumor, not significant (p = .057). Another study ap- MOGENSEN AND JEMEC TABLE 5. Confocal Microscopy Authors, year Gonzalez and Tannous, 200276 Marra et al., 2005123 Nori et al., 2004124 Gerger et al., 2005125 Number and pathology of patients Question asked Results 5 BCCs In vivo CM compared to histopathology Characteristic CM features in all specimens. 3 BCCs CM compared to histopathology Diagnostic accuracy of 5 CM criteria for in vivo BCC diagnosis Diagnostic accuracy CM in MMS untreated fresh biopsies Diagnostic accuracy in vivo CM aluminum chloride contrast Ex vivo CM of Stage 1 MMS excisions Above confirmed. 152 lesions (83 BCCs and benign) 20 BCCs Tannous et al., 2003126 5 BCCs Chung et al., 200475 92 BCCs, 23 SCCs Sauermann et al., 2002127 Aghassi et al., 2000128 12 BCCs 6 AKs, 1 SCC Diagnostic value of CM vascular pattern CM diagnostic features Sensitivity 93.9% and specificity 78.3% was found using three criteria and 95.7% and 82.9%, respectively. Sensitivity ranging from 44% to 100% and a specificity of 100% for all five criteria. 100% sensitivity in Stage 1 MMS and 80% sensitivity in Stage 2. CM may be an alternative to frozen sections in large nodular BCC. Difficulties in recognizing SCC in situ and poor image quality. Vascular pattern of BCC in CM can be used diagnostically. CM able to distinguish pathologic features of epidermal neoplasms: 100% show nuclear enlargement and pleomorphism. BCC, basal cell carcinoma; CM, confocal microscopy; MMS, Mohs micrographic surgery. plied two different algorithms in data analysis of bispectral fluorescence and showed promising results in demarcation of skin lesions in 15 BCC patients.94 Also two different fluorescence systems showed a clear demarcation of BCC in 2 patients with several BCC lesions.95 In an in vivo study, 55 patients with oral SCC were studied with respect to endogenous fluorescence. The intensity of the fluorescence significantly corresponded with the pathologic tumor and node categories of SCC (po.01).83,96 Terahertz Imaging Terahertz pulsed imaging (TPI) is a novel, noninvasive, imaging modality. It uses pulses of electromagnetic radiation in the frequency range of 0.1 to 10 THz. Water has strong absorption over the entire THz range, and water content in the skin is a source of image contrast.97 TPI has potential use in NMSC diagnosis. A significant difference between the re- sponse of THz radiation in normal skin and BCC has been reported.98,99 In a study of 18 BCCs both in vivo (5 BCCs) and ex vivo TPI analysis was performed. In vivo regions of contrast were seen in all THz images and correlated well with histology.100 Electrical Impedance The impedance of the skin is an electrical entity that can be described in complex numbers by resistance and reactance. A pilot study had found statistical difference in electrical impedance values was found between BCC and normal skin.101 This was confirmed in a study of 34 BCC patients.102 Statistical difference in electrical impedance values was found between BCC and normal skin; however, diagnostic accuracy could not be assessed. The electrical impedance system was elaborated further, and the probe equipped with microinvasive electrodes to bypass the barrier function of the high impedance of stratum corneum. The lesions were 99 benign nevi, 33:10:OCTOBER 2007 1169 DIAGNOSTIC ACCURACY OF NONMELANOMA SKIN CANCER DIAGNOSTIC TESTS 28 BCCs, and 13 MMS.103 Sensitivity for separation of BCC from benign nevi was 96% and specificity 86%, when using the noninvasive probe. The invasive probe had higher diagnostic accuracy only in MM. The choice of electrode can be considered application-dependent. A study of 35 BCC patients compares electrical impedance, transepidermal water loss (TEWL), and LD in diagnosing nodular and superficial BCC.104 In accordance with other studies, statistically significant differences between electrical impedance and BCC was found (po.001), but no differences between subtypes were found. In addition, TEWL and LD values had similar p values in discriminating BCC from normal skin. Increased TEWL values are ascribed to the decreased barrier function of the skin due to the pathologic processes of BCC. The assumption is that the increased LD values are due to increased angiogenesis and vasodilation in BCC. depth, and the location of the tumor between MRI and histopathology are in good agreement.107 A retrospective study of 33 NMSC patients (20 BCCs, 12 SCCs, 1 mixed) estimated accuracy of MRI and CT; the findings were compared to histopathology.108 Patients were seen for both primary assessment and follow-up. MR and CT localized the lesions in 29 of 33 patients; of the 4 tumors not identified, three-fourths of patients had mean disease-free survival at 33 months and the fourth patient developed recurrence at 52 months. In a study of 35 patients of whom 18 had perineural spread of BCC and SCC, based on clinical and histopathologic investigation, CT and MR109 showed that positive perineural spread inversely correlated with 5-year survival rate. Patients who were imaging-positive had a 5-year survival of 50% and for imaging-negative patients it was 86% (p = .049). In this study MRI seems to be informative in estimating prognosis. CT, PET, and MR CT is based on the X-ray principal, whereas PET is an imaging technique that detects positron release from radioactive substances and provides cross-sectional physiologic information. PET imaging commonly uses 2-deoxy-2-18F-fluoro-D-glucose (FDG), a positron-imaging agent, to measure the metabolic rate of tissue noninvasively. Tumors can be metabolically more active than normal tissue, thus mobilization of the image tracer can be detected by PET scanning. FDG-PET has been investigated in diagnosis of NMSC.105 Six patients with BCC larger than 1 cm were examined by PET scanning. BCC could only be identified in 3 of 6 patients. Another study compared FDG-PET NMSC diagnosis in patients with head and neck tumors with physical examination, ultrasonography, and CT.106 In a group of 56 patients (43 SCCs), detecting the primary tumor site with PET had a sensitivity of 95% (95% CI, 80%–98%) and a specificity of 100% (95% CI, 62%–100%). There was no statistical difference between PET and CT diagnosis. MRI makes use of the magnetic properties of hydrogen nucleus (the protons). MRI has been applied to studies of SCC and morphologic information about the shape, the 1170 D E R M AT O L O G I C S U R G E RY Conclusion A broad variety of diagnostic technologies are becoming available for noninvasive diagnosis of NMSC. The reference standard, skin biopsy and histopathologic assessment, is, however, not yet to be replaced, because state-of-the-art diagnostic research has only been performed with few of the mentioned new diagnostic methods and technologies. Many of the technologies seem to offer an adequate diagnostic accuracy, especially as a supplement to clinical diagnosis. For all areas of new diagnostic tests and technologies in NMSC the clinical role remains to be established in larger, independent studies. References 1. Rigel DS, Friedman R, Dzubow LM, et al. Cancer of the skin. Philadelphia: Elsevier Saunders; 2004. p. 736S. 2. Hallock GG, Lutz DA. Prospective study of the accuracy of the surgeon’s diagnosis in 2000 excised skin tumors. Plast Reconstr Surg 1998;101:1255–61. 3. Marghoob AA, Swindle LD, Moricz CZ, et al. Instruments and new technologies for the in vivo diagnosis of melanoma. J Am Acad Dermatol 2003;49:777–97. 4. Gluud C, Gluud LL. Evidence based diagnostics. BMJ 2005;330:724–6. MOGENSEN AND JEMEC 5. Knottnerus JA. The evidence base of clinical diagnosis. London: BMJ Books; 2002. 6. Whited JD, Horner RD, Hall RP, et al. The influence of history on interobserver agreement for diagnosing actinic keratoses and malignant skin lesions. J Am Acad Dermatol 1995;33:603–7. 7. Whited JD, Hall RP. Diagnostic accuracy and precision in assessing dermatologic disease: problem or promise? Arch Dermatol 1997;133:1409–15. 8. Schwartzberg JB, Elgart GW, Romanelli P, et al. Accuracy and predictors of basal cell carcinoma diagnosis. Dermatol Surg 2005;31:534–7. 9. Morrison A, O’Loughlin S, Powell FC. Suspected skin malignancy: a comparison of diagnoses of family practitioners and dermatologists in 493 patients. Int J Dermatol 2001;40:104–7. 10. Leffell DJ, Chen YT, Berwick M, et al. Interobserver agreement in a community skin cancer screening setting. J Am Acad Dermatol 1993;28:1003–5. 11. Har-Shai Y, Hai N, Taran A, et al. Sensitivity and positive predictive values of presurgical clinical diagnosis of excised benign and malignant skin tumors: a prospective study of 835 lesions in 778 patients. Plast Reconstr Surg 2001;108:1982–9. 12. Ek EW, Giorlando F, Su SY, et al. Clinical diagnosis of skin tumours: how good are we? ANZ J Surg 2005;75:415–20. 13. Davis DA, Donahue JP, Bost JE, et al. The diagnostic concordance of actinic keratosis and squamous cell carcinoma. J Cutan Pathol 2005;32:546–51. 14. Cooper SM, Wojnarowska F. The accuracy of clinical diagnosis of suspected premalignant and malignant skin lesions in renal transplant recipients. Clin Exp Dermatol 2002;27:436–8. 15. Oliveria SA, Chau D, Christos PJ, et al. Diagnostic accuracy of patients in performing skin self-examination and the impact of photography. Arch Dermatol 2004;140:57–62. 16. Russell EB, Carrington PR, Smoller BR. Basal cell carcinoma: a comparison of shave biopsy versus punch biopsy techniques in subtype diagnosis. J Am Acad Dermatol 1999;41:69–71. 17. Bakis S, Irwig L, Wood G, et al. Exfoliative cytology as a diagnostic test for basal cell carcinoma: a meta-analysis. Br J Dermatol 2004;150:829–36. 18. Vega-Memije E, Martinez-de-Larios N, Waxtein LM, et al. Cytodiagnosis of cutaneous basal and squamous cell carcinoma. Int J Dermatol 2000;39:116–20. 19. Saldanha G, Fletcher A, Slater DN. Basal cell carcinoma: a dermatopathological and molecular biological update. Br J Dermatol 2003;148:195–202. 20. Walling HW, Fosko SW, Geraminejad PA, et al. Aggressive basal cell carcinoma: presentation, pathogenesis, and management. Cancer Metastasis Rev 2004;23:389–402. 24. Kamiya M, Ichiki Y, Kamiya H, et al. Detection of nonmelanoma skin cancer micrometastases in lymph nodes by using reverse transcriptase-polymerase chain reaction for keratin 19 mRNA. Br J Dermatol 2003;149:998–1005. 25. Biesterfeld S, Josef J. Differential diagnosis of keratoacanthoma and squamous cell carcinoma of the epidermis by MIB-1 immunohistometry. Anticancer Res 2002;22:3019–23. 26. Trotter MJ, Bruecks AK. Interpretation of skin biopsies by general pathologists: diagnostic discrepancy rate measured by blinded review. Arch Pathol Lab Med 2003;127:1489–92. 27. Lacour JP. Carcinogenesis of basal cell carcinomas: genetics and molecular mechanisms. Br J Dermatol 2002;146(Suppl 61):17–9. 28. Ortonne JP. From actinic keratosis to squamous cell carcinoma. Br J Dermatol 2002;146(Suppl 61):20–3. 29. Park WS, Lee HK, Lee JY, et al. p53 mutations in solar keratoses. Hum Pathol 1996;27:1180–4. 30. Wong CS, Strange RC, Lear JT. Basal cell carcinoma. BMJ 2003;327:794–8. 31. Jovanovic DL, Katic V, Jovanovic B. Value of preoperative determination of skin tumor thickness with 20-MHz ultrasound. Arch Dermatol 2005;141:269–70. 32. Karaman GC, Karaman CZ, Sendur N, et al. Power Doppler ultrasonography for the evaluation of skin tumors other than malignant melanoma. Eur Radiol 2001;11:1111–6. 33. Moore JV, Allan E. Pulsed ultrasound measurements of depth and regression of basal cell carcinomas after photodynamic therapy. relationship to probability of 1-year local control. Br J Dermatol 2003;149:1035–40. 34. Allan E, Pye DA, Levine EL, et al. Non-invasive pulsed ultrasound quantification of the resolution of basal cell carcinomas after photodynamic therapy. Lasers Med 2002;17: 230–7. 35. Gupta AK, Turnbull DH, Foster FS, et al. High frequency 40-MHz ultrasound: a possible noninvasive method for the assessment of the boundary of basal cell carcinomas. Dermatol Surg 1996;22:131–6. 36. Harland CC, Bamber JC, Gusterson BA, et al. High frequency, high resolution B-scan ultrasound in the assessment of skin tumours. Br J Dermatol 1993;128:525–32. 37. Gropper CA, Stiller MJ, Shupack JL, et al. Diagnostic highresolution ultrasound in dermatology. Int J Dermatol 1993; 32:243–50. 38. Jemec GB, Gniadecka M, Ulrich J. Ultrasound in dermatology. Part I. High frequency ultrasound. Eur J Dermatol 2000;10: 492–7. 21. Lind AC, Bewtra C, Healy JC, et al. Prospective peer review in surgical pathology. Am J Clin Pathol 1995;104:560–6. 39. Lassau N, Spatz A, Avril MF, et al. Value of high-frequency US for preoperative assessment of skin tumors. Radiographics 1997;17:1559–65. 22. Olhoffer IH, Lazova R, Leffell DJ. Histopathologic misdiagnoses and their clinical consequences. Arch Dermatol 2002;138:1381–3. 40. Marques J, Cueto L, Roldan F, et al. Ultrasound study of skin tumors. Radiologia 2002;44:55–60. 23. Brochez L, Verhaeghe E, Grosshans E, et al. Inter-observer variation in the histopathological diagnosis of clinically suspicious pigmented skin lesions. J Pathol 2002;196:459–66. 41. Vaillant L, Grognard C, Machet L, et al. High resolution ultrasound imaging to assess skin tumors prior to cryosurgery. Ann Dermatol Venereol 1998;125:500–4. 33:10:OCTOBER 2007 1171 DIAGNOSTIC ACCURACY OF NONMELANOMA SKIN CANCER DIAGNOSTIC TESTS 42. Gross U, Suter L, Hundeiker M. 20-MHz sonography as a planning aid in the therapy of skin tumours. Akt Dermatol 1993;19:32–5. 43. Costa P, Ghillani M, Papadia F, et al. Superficial ultrasound in the assessment of skin tumours: indications and limitations. Riv Ital Chir Plast 1992;24:263–9. 44. Nitsche N, Hoffmann K, Iro H. Ultrasound diagnosis of skin tumours. HNO 1992;40:97–100. 45. Edwards C, Al-Aboosi MM, Marks R. The use of A-scan ultrasound in the assessment of small skin tumours. Br J Dermatol 1989;121:297–304. 46. Hoffmann K, Stucker M, el-Gammal S, et al. [Digital 20 MHz sonography of basalioma in the B-scan]. Hautarzt 1990;41: 333–9. 47. el Gammal S, Auer T, Hoffmann K, et al. High-resolution ultrasound of the human epidermis. In: Non-invasive methods of the skin. Boca Raton (FL): CRC Press; 1995. 48. el Gammal S, El Gammal C, Altmeyer PJ, et al. High resolution sonography of the skin. In: Non-invasive methods of the skin. 2nd ed. Boca Raton (FL): CRC Press; 2006. 49. Serup J, Keiding J, Fullerton A, et al. High-frequency ultrasound examination of the skin. In: Non-invasive methods of the skin. 2nd ed. Boca Raton (FL): CRC Press; 2006. 50. Wortsman XC, Holm EA, Wulf HC, et al. Real-time spatial compound ultrasound imaging of skin. Skin Res Technol 2004;10:23–31. 51. Bessoud B, Lassau N, Koscielny S, et al. High-frequency sonography and color Doppler in the management of pigmented skin lesions. Ultrasound Med Biol 2003;29:875–9. 52. Rallan D, Harland CC. Ultrasound in dermatologyFbasic principles and applications. Clin Exp Dermatol 2003;28:632–8. 53. Ruocco E, Argenziano G, Pellacani G, et al. Noninvasive imaging of skin tumors. Dermatol Surg 2004;30:301–10. 54. Schmid-Wendtner MH, Burgdorf W. Ultrasound scanning in dermatology. Arch Dermatol 2005;141:217–24. 55. Bjerring P, Obitz ER, Cotton S. In vivo spectrophotometric evaluation of skin tumours using a new chromophore imaging system SIAscope. Melanoma Res 2001;11:s180. 56. Argenziano G, Zalaudek I, Corona R, et al. Vascular structures in skin tumors: a dermoscopy study. Arch Dermatol 2004;140:1485–9. 57. Zalaudek I, Argenziano G, Leinweber B, et al. Dermoscopy of Bowen’s disease. Br J Dermatol 2004;150:1112–6. 58. Kreusch JF. Vascular patterns in skin tumors. Clin Dermatol 2002;20:248–54. 59. Tycho A, Andersen P, Thrane L, et al. Optical coherence tomography in dermatology. In: Non-invasive methods and the skin. 2nd ed. Boca Raton (FL): CRC Press; 2006. 60. Fujimoto JG, Pitris C, Boppart SA, et al. Optical coherence tomography: an emerging technology for biomedical imaging and optical biopsy. Neoplasia 2000;2:9–25. 1172 D E R M AT O L O G I C S U R G E RY 61. Fujimoto JG. Optical coherence tomography for ultrahigh resolution in vivo imaging. Nat Biotechnol 2003;21: 1361–7. 62. Gambichler T, Moussa G, Sand M, et al. Applications of optical coherence tomography in dermatology. J Dermatol Sci 2005;40:85–94. 63. Pierce MC, Strasswimmer J, Park BH, et al. Advances in optical coherence tomography imaging for dermatology. 2004;123:458–63. 64. Welzel J, Lankenau E, Birngruber R, et al. Optical coherence tomography of the human skin. J Am Acad Dermatol 1997;37:958–63. 65. Welzel J. Optical coherence tomography in dermatology: a review. Skin Res Technol 2001;7:1–9. 66. Steiner R, Kunzi RK, Scharffetter KK. Optical coherence tomography: clinical applications in dermatology. Med Laser Application 2003;18:249–59. 67. Olmedo JM, Warschaw KE, Schmitt JM, et al. Optical coherence tomography for the characterization of basal cell carcinoma in vivo: a pilot study. J Am Acad Dermatol 2006; 55:408–12. 68. Gambichler T, Boms S, Stucker M, et al. Comparison of histometric data obtained by optical coherence tomography and routine histology. J Biomed Opt 2005;10:44008. 69. Bechara FG, Gambichler T, Stucker M, et al. Histomorphologic correlation with routine histology and optical coherence tomography. Skin Res Technol 2004;10:169–73. 70. Jensen LK, Thrane L, Andersen PE, et al. Optical coherence tomography in clinical examination of non-pigmented skin malignancies. Proc of SPIE-OSA Biomed Optics. SPIE 2003;5140:160–7. 71. Strasswimmer J, Pierce MC, Park BH, et al. Polarization-sensitive optical coherence tomography of invasive basal cell carcinoma. J Biomed Opt 2004;9:292–8. 72. Buchwald HJ, Muller A, Kampmeier J, et al. Optical coherence tomography versus ultrasound biomicroscopy of conjunctival and eyelid lesions. Klin Monatsblatter Augenheilkunde 2003;220:822–9. 73. Kollias N, Stamatas GN. Optical non-invasive approaches to diagnosis of skin diseases. J Invest Dermatol Symp Proc 2002;7:64–75. 74. Selkin B, Rajadhyaksha M, Gonzalez S, et al. In vivo confocal microscopy in dermatology. Dermatol Clin 2001;19:369–77. 75. Chung VQ, Dwyer PJ, Nehal KS, et al. Use of ex vivo confocal scanning laser microscopy during Mohs surgery for nonmelanoma skin cancers. Dermatol Surg 2004;30:1470–8. 76. Gonzalez S, Tannous Z. Real-time, in vivo confocal reflectance microscopy of basal cell carcinoma. J Am Acad Dermatol 2002;47:869–74. 77. Gonzalez S, Gilaberte-Calzada Y, Gonzalez-Rodriguez A, et al. In vivo reflectance-mode confocal scanning laser microscopy in dermatology. Adv Dermatol 2004;20:371–87. 78. Suihko C, Swindle LD, Thomas SG, et al. Fluorescence fibreoptic confocal microscopy of skin in vivo: microscope and fluorophores. Skin Res Technol 2005;11:254–67. MOGENSEN AND JEMEC 79. Gniadecka M, Wulf HC, Nielsen OF, et al. Distinctive molecular abnormalities in benign and malignant skin lesions: studies by Raman spectroscopy. Photochem Photobiol 1997;66:418–23. 80. Gniadecka M, Philipsen PA, Sigurdsson S, et al. Melanoma diagnosis by Raman spectroscopy and neural networks: structure alterations in proteins and lipids in intact cancer tissue. J Invest Dermatol 2004;122:443–9. 81. McIntosh LM, Jackson M, Mantsch HH, et al. Infrared spectra of basal cell carcinomas are distinct from non-tumor-bearing skin components. J Invest Dermatol 1999;112:951–6. 82. Nijssen A, Bakker Schut TC, Heule F, et al. Discriminating basal cell carcinoma from its surrounding tissue by Raman spectroscopy. J Invest Dermatol 2002;119:64–9. 83. Onizawa K, Yoshida H, Saginoya H. Chromatic analysis of autofluorescence emitted from squamous cell carcinomas arising in the oral cavity: a preliminary study. Int J Oral Maxillofac Surg 2000;29:42–6. 84. Panjehpour M, Julius CE, Phan MN, et al. Laser-induced fluorescence spectroscopy for in vivo diagnosis of non-melanoma skin cancers. Lasers Surg Med 2002;31:367–73. 85. Sigurdsson S, Philipsen PA, Hansen LK, et al. Detection of skin cancer by classification of Raman spectra. IEEE Trans Biomed Eng 2004;51:1784–93. 86. Stenquist B, Ericson MB, Strandeberg C, et al. Bispectral fluorescence imaging of aggressive basal cell carcinoma combined with histopathological mapping: a preliminary study indicating a possible adjunct to Mohs micrographic surgery. Br J Dermatol 2006;154:305–9. tion for correlation with histopathologic extent of basal cell carcinoma. J Biomed Opt 2005;10:034009. 95. Andersson-Engels S, Canti G, Cubeddu R, et al. Preliminary evaluation of two fluorescence imaging methods for the detection and the delineation of basal cell carcinomas of the skin. Lasers Surg Med 2000;26:76–82. 96. Onizawa K, Okamura N, Saginoya H, et al. Characterization of autofluorescence in oral squamous cell carcinoma. Oral Oncol 2003;39:150–6. 97. Pickwell E, Cole BE, Fitzgerald AJ, et al. In vivo study of human skin using pulsed terahertz radiation. Phys Med 2004;49:1595–607. 98. Woodward RM, Cole BE, Wallace VP, et al. Terahertz pulse imaging in reflection geometry of human skin cancer and skin tissue. Phys Med 2002;47:3853–63. 99. Woodward RM, Wallace VP, Pye RJ, et al. Terahertz pulse imaging of ex vivo basal cell carcinoma. J Invest Dermatol 2003;120:72–8. 100. Wallace VP, Fitzgerald AJ, Shankar S, et al. Terahertz pulsed imaging of basal cell carcinoma ex vivo and in vivo. Br J Dermatol 2004;151:424–32. 101. Emtestam L, Nicander I, Stenstrom M, et al. Electrical impedance of nodular basal cell carcinoma: a pilot study. Dermatology 1998;197:313–6. 102. Aberg P, Nicander I, Holmgren U, et al. Assessment of skin lesions and skin cancer using simple electrical impedance indices. Skin Res Technol 2003;9:257–61. 87. Svanberg K, Wang I, Colleen S, et al. Clinical multi-colour fluorescence imaging of malignant tumoursFinitial experience. Acta Radiol 1998;39:2–9. 103. Aberg P, Geladi P, Nicander I, et al. Non-invasive and microinvasive electrical impedance spectra of skin cancerFa comparison between two techniques. Skin Res Technol 2005;11:281–6. 88. McIntosh LM, Summers R, Jackson M, et al. Towards non-invasive screening of skin lesions by near-infrared spectroscopy. J Invest Dermatol 2001;116:175–81. 104. Kuzmina N, Talme T, Lapins J, et al. Non-invasive preoperative assessment of basal cell carcinoma of nodular and superficial types. Skin Res Technol 2005;11:196–200. 89. Choi J, Choo J, Chung H, et al. Direct observation of spectral differences between normal and basal cell carcinoma (BCC) tissues using confocal Raman microscopy. Biopolymers 2005;77:264–72. 105. Fosko SW, Hu W, Cook TF, et al. Positron emission tomography for basal cell carcinoma of the head and neck. Arch Dermatol 2003;139:1141–6. 90. Inaguma M, Hashimoto K. Porphyrin-like fluorescence in oral cancer: in vivo fluorescence spectral characterization of lesions by use of a near-ultraviolet excited autofluorescence diagnosis system and separation of fluorescent extracts by capillary electrophoresis. Cancer 1999;86:2201–11. 91. Na R, Stender IM, Wulf HC. Can autofluorescence demarcate basal cell carcinoma from normal skin? A comparison with protoporphyrin IX fluorescence. Acta Derm Venereol 2001;81:246–9. 92. Brancaleon L, Durkin AJ, Tu JH, et al. In vivo fluorescence spectroscopy of nonmelanoma skin cancer. Photochem Photobiol 2001;73:178–83. 93. Sterenborg NJ, Thomsen S, Jacques SL, et al. In vivo fluorescence spectroscopy and imaging of human skin tumors. Dermatol Surg 1995;21:821–2. 94. Ericson MB, Uhre J, Strandeberg C, et al. Bispectral fluorescence imaging combined with texture analysis and linear discrimina- 106. Sigg MB, Steinert H, Gratz K, et al. Staging of head and neck tumors: [18F] fluorodeoxyglucose positron emission tomography compared with physical examination and conventional imaging modalities. J Oral Maxillofac Surg 2003;61:1022–9. 107. Querleux B. Nuclear magnetic resonance (NMR) examination of the skin in vivo. In: Non-invasive methods of the skin. 2nd ed. Boca Raton (FL): CRC Press; 2006. 108. Lanka B, Turner M, Orton C, et al. Cross-sectional imaging in non-melanoma skin cancer of the head and neck. Clin Radiol 2005;60:869–77. 109. Williams LS, Mancuso AA, Mendenhall WM. Perineural spread of cutaneous squamous and basal cell carcinoma. CT and MR detection and its impact on patient management and prognosis. Int J Radiat Oncol Biol Phys 2001;49:1061–9. 110. Whited JD, Hall RP, Simel DL, et al. Primary care clinicians’ performance for detecting actinic keratoses and skin cancer. Arch Intern Med 1997;157:985–90. 33:10:OCTOBER 2007 1173 DIAGNOSTIC ACCURACY OF NONMELANOMA SKIN CANCER DIAGNOSTIC TESTS 111. Westbrook RH, Goyal N, Gawkrodger DJ. Diagnostic accuracy for skin cancer: comparison of general practitioner with dermatologist and dermatopathologist. J Dermatolog Treat 2006;17:57–8. 122. Chin CW, Foss AJ, Stevens A, et al. Differences in the vascular patterns of basal and squamous cell skin carcinomas explain their differences in clinical behaviour. J Pathol 2003;200: 308–13. 112. Renshaw AA, Pinnar NE, Jiroutek MR, et al. Blinded review as a method for quality improvement in surgical pathology. Arch Pathol Lab Med 2002;126:961–3. 123. Marra DE, Torres A, Schanbacher CF, et al. Detection of residual basal cell carcinoma by in vivo confocal microscopy. Dermatol Surg 2005;31:538–41. 113. Bertolotto M, Serafini G, Dogliotti L, et al. Primary and secondary malignancies of the penis: ultrasound features. Abdom Imaging 2005;30:108–12. 124. Nori S, Rius-Diaz F, Cuevas J, et al. Sensitivity and specificity of reflectance-mode confocal microscopy for in vivo diagnosis of basal cell carcinoma: a multicenter study. J Am Acad Dermatol 2004;51:923–30. 114. Lont AP, Besnard AP, Gallee MP, et al. A comparison of physical examination and imaging in determining the extent of primary penile carcinoma. BJU Int 2003;91:493–5. 115. Stucker M, Horstmann I, Nuchel C, et al. Blood flow compared in benign melanocytic naevi, malignant melanomas and basal cell carcinomas. Clin Exp Dermatol 1999;24:107–11. 116. Schroder RJ, Maurer J, Zlowodski M, et al. Vascularization of malignant and benign skin tumours measured by D-galactosebased signal-enhanced colour Doppler sonography. Acta Radiol 2001;42:294–301. 117. Zalaudek I. Dermoscopy subpatterns of nonpigmented skin tumors. Arch Dermatol 2005;141:532. 118. Menzies SW. Dermoscopy of pigmented basal cell carcinoma. Clin Dermatol 2002;20:268–9. 119. Zalaudek I, Argenziano G, Soyer HP, et al. Three-point checklist of dermoscopy: an open internet study. Br J Dermatol 2006;154:431–7. 125. Gerger A, Horn M, Koller S, et al. Confocal examination of untreated fresh specimens from basal cell carcinoma: implications for microscopically guided surgery. Arch Dermatol 2005;141:1269–74. 126. Tannous Z, Torres A, Gonzalez S. In vivo real-time confocal reflectance microscopy: a noninvasive guide for Mohs micrographic surgery facilitated by aluminum chloride, an excellent contrast enhancer. Dermatol Surg 2003;29: 839–46. 127. Sauermann K, Gambichler T, Wilmert M, et al. Investigation of basal cell carcinoma [correction of carcionoma] by confocal laser scanning microscopy in vivo. Skin Res Technol 2002;8: 141–7. 128. Aghassi D, Anderson RR, Gonzalez S. Confocal laser microscopic imaging of actinic keratoses in vivo: a preliminary report. J Am Acad Dermatol 2000;43:42–8. 120. Otis LL, Piao D, Gibson CW, et al. Quantifying labial blood flow using optical Doppler tomography. Oral Surg Oral Med Pathol Oral Radiol Endod 2004;98:189–94. 121. Newell B, Bedlow AJ, Cliff S, et al. Comparison of the microvasculature of basal cell carcinoma and actinic keratosis using intravital microscopy and immunohistochemistry. Br J Dermatol 2003;149:105–10. 1174 D E R M AT O L O G I C S U R G E RY Address correspondence and reprint requests to: Mette Mogensen, MD, Department of Dermatology, University of Copenhagen, Roskilde Hospital, K^gevej 7-13, DK4000 Roskilde, Denmark, or e-mail: [email protected]