| Infrared micro-spectroscopy coupled with mathematical algorithms, in which the diagnosis is based on a physical (spectroscopic) measurement and the interpretation is carried out by multivariate statistical algorithms, provides an alternative approach to classical pathology practices. This novel approach is termed Spectral Pathology, where the investigation and diagnosis of disease in cellular specimens is Spectral Cytopathology (SCP), and the study and diagnosis of disease in tissue specimens is Spectral Histopathology (SHP). This methodology provides a robust, objective, and reproducible diagnostic tool where spectroscopic differences reveal intrinsic biochemical changes that can be used as spectral biomarkers to diagnose disease before the manifestation of morphological changes.;Detailed in this dissertation are novel applications of this technique, namely 1) the optimization of sample preparation techniques, 2) SCP of the nasopharyngeal and oral cavities, and 3) SHP of lymph node tissue sections.;In SCP, sample preparation techniques, specifically fixation protocols, must preserve the biochemical composition of the biological sample so that diagnostic spectral changes are not masked. A thorough investigation was designed to evaluate the effects of sample type and fixation protocol over a month long observation period. The results suggest minute spectral changes induced by fixation where changes due to disease are greater.;SCP efforts toward the development of a pre-screening tool for oral disease contributed to an oral pre-clinical trial that commenced in 2010 at Northeastern University. This study had two main goals: one, develop a more representative database of normal oral cytology samples and two, expand databases representative of external influences such as viral contributions, tobacco use, medication, etc. The pre-clinical trial collected 279 samples from 93 participants and results mimicked preliminary data, which indicate spectral changes unique to anatomical region, viral infection, and disease. Also, SCP of nasopharyngeal samples was sought to develop correlations between different regions of the head and neck to pinpoint differences within these regions.;SHP was applied to normal lymph node tissue sections to interpret B-lymphocyte activation. Lymphocyte activation indicates the presence and response against a pathogen, regardless of the inciting pathogen's etiology. Having the possibility to detect a specific malignancy and pinpoint the origin without the presence of a malignant cell would provide clinicians a potent tool to detect earlier stages of disease. The results reported provide a proof-of-concept study that reveals SHP's potential to screen lymph nodes and differentiate B-lymphocyte activation in response to circulating tumor cells without the presence of metastatic cells. |
