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Colposcopy in pre-malignant lesions and oral squamous cell carcinoma: Linking threads of clinical, histopathological and colposcopic inferences.

CONTEXT
The single most important factor that is known to improve the end result of head and neck cancer is the early diagnosis of these cancers while they are still localized and can be treated with a high probability of cure. Early diagnosis of cancer plays a lifesaving pivotal role in overall management. The technique of colposcopy enables evaluation of changes in surface topography and vascular patterns of the lining mucosa thus, aiding in selecting the most appropriate site of biopsy ruling out the possibility of taking biopsy from the most representative area supposed to reveal epithelial dysplasia. In view of the intra-oral application of micro-colposcopy, it was felt that colposcopy might provide a useful aid for the early enough diagnosis of oral precancerous and cancerous lesions and conditions affecting the oral mucosa to improve the prognosis.


AIMS
To clinicopathologically correlate cases of oral precancers; correlate the surface characteristics revealed by micro-colposcopy with the histopathological diagnoses of the sites under observation; and map out the areas of surface dysplasia to indicate the full extent of epithelial changes before taking the biopsy specimen to take specimen from areas most representative of dysplasic features (guided biopsies).


MATERIALS AND METHODS
A total 90 subjects were studied including 30 cases of oral submucous fibrosis, 20 cases each of hyperkeratotic lesions including homogeneous and nonhomogeneous leukoplakias and oral lichen planus and 20 cases of clinically diagnosed and histopathologically proven oral squamous cell carcinoma.


RESULTS
In this study, a sensitivity of colposcopic screening test came-out to be about 71% while specificity was about 91%. Positive predictive value was 91%.


CONCLUSION
Although the degree of abnormality in colposcopic findings can be predicted by the vascular patterns of the lesion, the major advantage of colposcopy is to outline the most suspicious lesion for histologic diagnosis by directed biopsy, which is the mainstay in establishing the correct diagnosis. Colposcopy is valuable in the detection of early cancerous lesions. However the final diagnosis must rely on a meticulous histopathological examination by an expert pathologist.