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4 COMMENTARY
Oral Cancer Screening in High-Risk Individuals: The Need
for Awareness by the Primary Care Physician
Frank Lalezarzadeh, BS,1 David Folk, MD,2 Jessie J. Hanna, BS,3 and Boris Paskhover, MD2
1 Albert
Einstein College of Medicine, Bronx, NY 10461, 2 Yale–New Haven Hospital, Division of Otorhinolaryngology, New Haven, CT,
Wood Johnson Medical School, New Brunswick, NJ.
3 Robert
INTRODUCTION
Oral cancer is an important and growing global health
problem that currently accounts for about 3% of worldwide malignancies. It is usually synonymous with squamous cell carcinoma of the oral cavity. Most potentially
malignant disorders are found on the buccal mucosa,
lower gingiva, tongue, and floor of the mouth, with the
remaining cases distributed throughout the rest of the
oral cavity (Epstein et al., 2008). The American Cancer
Society has estimated that in the United States there
were 23,000 new cases of oral cancer, with 5,300 deaths,
in 2010 (Steele and Meyers, 2011). Incidence and mortality are even higher in developing countries, where
cancer of the oral cavity ranks among the three most
common types of cancer. In India, the age-standardized
incidence rate of oral cancer is reported at 12.6 per
100,000 people (Petersen, 2009). Such staggering numbers have led organizations across the globe, including
the World Health Organization, to take steps to ensure
that prevention of oral cancer is an integral part of
national cancer-control programs (Petersen, 2009).
Despite the increased attention to oral cancer and the
great strides made in treatment options, the five-year
survival rate has not changed appreciably in the past
several decades, remaining at 50–60% since 1974 (Steele
and Meyers, 2011). One major factor that has prevented
improvement in the survival rate is that presentation is
often symptomatic only at a late stage, when five-year
survival rates are close to 20% (Steele and Meyers, 2011).
The ability to diagnose oral squamous cell carcinoma at
early stages is crucial to improving survival rates, quality of life, and treatment efficacy. Visual inspection and
physical examination continue to be the predominant
initial means of screening for oral cancer. In a systematic
review of the literature, Kujan et al. (2005) concluded
that there was insufficient evidence either to support or
to refute the use of screening for oral cancer in the general population. However, a randomized trial in India
of more than 100,000 high-risk patients found a 34%
reduction in mortality due to oral cancer in people who
underwent regular visual screening by trained healthcare workers, compared to those who did not undergo
regular visual screening (Sankaranarayanan et al., 2005).
Based on these findings, it is evident that the oral cavity
is an easily accessible site for screening by physicians and
other healthcare workers in order to detect early oral
neoplasia.
Unfortunately, most Americans, particularly populations at increased risk of oral cancer, do not receive
routine oral healthcare. It is incumbent upon the medical community, particularly primary care physicians, to
conduct opportunistic screenings on high-risk patients
presenting for healthcare services in nondental settings.
Although many physicians are not trained to screen for
oral cancer (Mouradian et al., 2005), this does not imply
a reluctance to learn about the importance of screening or to adopt the tools necessary to screen patients. A
recent pilot study found that after undergoing a oneday training program, physicians indicated that they
“definitely intended to change their clinical practice as a
result of the training” (LeHew et al., 2009).
This commentary undertakes to review and update the
risk factors for oral squamous cell cancer, to review the
nature of oral precancerous lesions, to describe effective techniques that can be used in screening, and to
help educate primary care physicians to screen highrisk patients effectively for oral cancer at early stages
to decrease mortality and increase the five-year survival
rate from oral cancer.
EPIDEMIOLOGY OF OROPHARYNGEAL SQUAMOUS CELL
CARCINOMA
Oral cavity cancer is a major contributor to the global
burden of cancer (Petersen, 2009). Each year an estimated 263,000 new cases of oral cavity cancer arise
worldwide, resulting in approximately 127,000 deaths
(International Agency for Research on Cancer, 2008).
Oral squamous cell carcinoma is associated with a number of risk factors, of which tobacco and alcohol use
present the greatest opportunity for intervention. To
date it has been difficult to discern the contribution of
these risk factors to oral cancers because of their associated comorbidities. Additionally, several studies have
shown a synergistic effect of tobacco and excessive use
of alcohol on the incidence of oropharyngeal squamous
cell carcinoma (Petersen, 2009). Furthermore, a history
of prior upper aerodigestive tract cancer confers a ninefold increase in the relative risk of subsequent oropharyngeal carcinoma compared to the general population.
Other known risk factors include betel nut chewing, oral
human papillomavirus infection, chronic immunosuppression following solid organ transplant, hematopoietic cell transplant, and possibly HIV infection and AIDS
(Warnakulasuriya, 2009). It is essential for the specialist
The Einstein Journal of Biology and Medicine
39
4 COMMENTARY
Oral Cancer Screening in High-Risk Individuals: The Need for Awareness by the Primary Care Physician
and primary care physician alike to be aware of all the
risk factors in establishing a patient history.
A number of clinical lesions in the oral cavity have been
described as premalignant, and are specifically regarded
as precursors to oral squamous cell carcinoma. These
include leukoplakia, erythroplakia, dysplastic leukoplakia, dysplastic lichenoid lesion, oral submucous fibrosis,
and lichen planus (Epstein et al., 2008). About 5–18% of
epithelial dysplasias undergo malignant transformation
(Axéll et al., 1996). Several factors are associated with
the increased progression of premalignant lesions to
cancer: these include color (red, red/white), irregularity
(lack of homogeneity), surface texture (granular, verrucous), and location (floor of the mouth, ventral or posterolateral border of the tongue) (Shiboski et al., 2000).
Thus, the well-described appearance of premalignant
lesions in the oral cavity further underscores the value
of a thorough physical exam.
Estimates suggest that in the year 2011, 39,400 new
cases of oropharyngeal cancer were diagnosed in the
United States. In addition, 7,900 deaths were associated
with oropharyngeal cancer. Despite the ready accessibility of the oral cavity to direct examination, these malignancies are often still not detected until a late stage and,
as a result, the survival rate for oral cancer has remained
essentially unchanged over the past three decades. The
five-year survival rate for early-stage tumors approaches
80% but falls below 30% for stage 4 tumors (National
Cancer Institute, 2011).
CURRENT GUIDELINES FOR SCREENING
There are currently no definitive guidelines for screening
for oral cancer. In 2004, the U.S. Preventive Services Task
Force report found that there was not enough evidence
to recommend for or against screening for oral cancer
of smokers older than 50 and those at low risk (U.S.
Preventive Services Task Force, 2004). Despite the lack
of evidence to support screening of the general population, there is evidence that screening high-risk patients
does decrease mortality and may be a more viable strategy (Sankaranarayanan et al., 2005). The question often
arises: which medical providers should be conducting
these screenings? Early-stage cancers in the oral cavity
are more often identified by dentists, while late-stage
disease is more likely to be discovered by medical physicians (LeHew et al., 2009). Unfortunately, many of those
who are at high risk—smokers, African Americans, men,
and individuals of low socioeconomic status—will not
regularly see dentists and will be more likely to have
late-stage diagnoses. Therefore, incidental screening
of high-risk patients has been suggested when patients
are seen for other examinations by healthcare providers.
Primary care physicians can provide this type of screening for premalignant and squamous cell carcinomas in
target individuals.
40 EJBM, Copyright © 2012
CONCLUSION
Oral squamous cell carcinoma is a life-threatening disease with high morbidity and mortality costs. However,
it is potentially easily detectable; neither heavy and
expensive machinery nor invasive procedures are
required to identify early lesions. This easy accessibility
of the oral cavity to exam renders it an ideal target for
improved screening practices. Due to the modest investments of time and cost required by screening exams,
we recommend that primary care physicians assume a
frontline role in the battle against oral squamous cell
cancer. By actively defining those at high risk based on
the aforementioned risk factors, primary care physicians
can screen such patients when they come to the office
and help refer appropriate patients to an otorhinolaryngologist. Screening and educating patients about
lifestyle modifications can help significantly decrease
the prevalence of and mortality from oral squamous cell
carcinoma.
Corresponding Author:
einstein.yu.edu).
Frank
Lalezarzadeh
([email protected]
Author Contributions: All authors contributed equally to writing the manuscript.
Conflict of Interest Disclosures: The authors have completed and submitted
the ICMJE Form for Disclosure of Potential Conflicts of Interest. No conflicts
were noted.
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