Download UNIVERSITA` POLITECNICA DELLE MARCHE FACOLTÀ DI

UNIVERSITA’ POLITECNICA DELLE MARCHE
FACOLTÀ DI AGRARIA
CORSO DI DOTTORATO IN
“ALIMENTI E SALUTE”
V Ciclo - nuova serie
La microspettroscopia imaging FT-IR
e FT-NIR come tecnica diagnostica
Candidato
Dott. Paolo FERRARIS
Responsabile Scientifico
Prof. Franco RUSTICHELLI
Correlatore
Prof. Giorgio TOSI
Coordinatore
Prof. Natale G. FREGA
Ancona 2006
Vibrational spectroscopy can be considered a fast tool to achieve important information on molecular
and supramolecular structures of biological systems without laborious and invasive sampling
procedures. If infrared microscopy gives the possibility to perform a qualitative and quantitative
analysis even at the molecular level, infrared imaging can provide chemical and spatial information
simultaneously.
Due to the huge number of spectra in a spectral map and to the difficulty to understand all the
information available from these spectra, it is not always possible to use a few IR frequencies as
diagnostic bands of different histological structures. This limit can be overcome by using multivariate
data reduction and pattern recognition analysis.
In recent years many studies have been undertaken to evaluate the possibility of vibrational
spectroscopy for use in clinical diagnosis and prognosis.
Improvements to run spectra at the diffraction limits (around 6 m of spatial resolution) have been
introduced by the use of synchrotron radiation and of multi detector devices that allow to ‘go’ inside
the biochemistry of a single cell and to highlight its state of maturation, differentiation and
development.
However, the main objective of these researches remains the detection of the ‘early stage’ of a disease
and the set-up of a protocol by using a spectroscopic indicator for the screening of high risk patients.
Oral carcinomas have a 5% of incidence in head and neck tumours, a percentage that is rapidly
increasing with a clinical behaviour that is sometimes difficult to predict with classical
histopathology. In fact, this methodology, analysing bulk morphological aspects, not always affords
quantitative accuracy and elucidates the biochemical background of the pathological changes. Besides
traditional histopathology, proliferating activity and angiogenesis may provide important information
on tumour behaviour that can be used for a more accurate characterisation of the neoplasia. In
addition, the use of molecular markers can define those neoplasms responsible for an aggressive
clinical behaviour.
Recently, spectroscopic studies of tumours of tongue, gingiva, floor , cheek mucosa of the oral cavity
have shown that this technique can be of great diagnostic and prognostic value. In particular, the
keratin distribution (in poorly differentiated squamous cell carcinoma) and the use of band ratio
images allowed spectroscopic results to be in satisfactory accordance with clinical diagnostic even in
the grading of the neoplasia.
The aim of this work was to further investigate oral cavity neoplasia by comparing spectroscopic
results on cultured cells, inoculated and excised tissues with the aim to assess spectral similarities
among the different characterisation levels.
Breast cancer affects a large number of women between 40 and 55 years of age. It is estimated that 1
to 14 women in Greece (1 to 7 in USA) will develop breast cancer sometime during their life. An
early detection of this disease could expand the survival of women. In 1929 M. Cutler had the idea
that in breast cancers the cancer tissue should have different optical properties from the normal tissue
and should give shadow images of the breast. This diaphanography gave a “shadowgram” without
significant changes for clinical trials. Mammography is the only method now that is used for detection
of breast cancer and for screening of population. It is estimated that in screening mammography 530% of breast cancers have a false-negative mammogram because the result depends on fat and
density of the breast. The Magnetic Resonance Imaging (MRI) technique gives 0.1% negative false
result and is not used by women due to claustrophobia. Positron emission tomography (PET) has
better detection results but has a resolution of 2 mm and a large number of women are excluded for
several reasons. For the early diagnosis and therapy of breast cancer it is crucial to develop a nondestructive bio-analytical technique to obtain images of the breast, which must be independent of
breast shape and mass density in order to detect lesions which are difficult to scan with the existing
techniques. Breast tissue is too complex with high heterogeneity. It contains different proportions of
components, such as glandular epithelium, fibrous and adipose tissues, carcinomatous cells and
necrotic areas to be directly determined. Micro-FT-IR spectroscopy promises a lot in this field, since it
provides information about the structure and composition of biological materials. The infrared spectra
also do preserve histo-morphological aspects. In this work we used micro-infrared spectroscopy,
which enables us to detect and quantify the changes of the molecular structure of biological molecules
based on the measurements of functional spectral differences between healthy and cancer tissues.