Evaluation of role of cytodiagnostic techniques in detection of oral premalignant and malignant lesions: Study of 50 cases

Abstract

Aims and Objectives: In this study, we studied cytomorphological features and determined the sensitivity and specificity of cytology specimens obtained with simple instruments like toothbrush (modified brush biopsy), wooden spatula and analyzed without computer-assisted analysis. Settings and Design: Fifty patients attending outpatient clinics who exhibited oral lesions suspicious of premalignancy or malignancy were enrolled. All patients underwent scrapping by wooden ice cream stick and an oral brush biopsy using a baby toothbrush. The specimens were analyzed manually in a double-blinded fashion. Histopathological confirmation by a scalpel biopsy was obtained whenever possible. Chi square test and Fischer exact 't' test was used for statistical analysis. Results: In our study, brush cytology was better (P < 0.05) than scrape cytology in the criteria of cellularity, abnormal cell group adequacy and detection of higher grade of dysplasia. Also, we found that increased N: C ratio, nuclear pleomorphism, nucleoli and presence of micronuclei were the parameters statistically significant in oral carcinoma as compared to high grade dysplasia. Sensitivity of detecting malignancy by cytodiagnosis was 76.47% and false negative rate of 23.53% was present in our study. Conclusions: Modified brush biopsy is relatively easy, non invasive, OPD procedure, particularly an effective tool for screening small innocuous lesions for dysplasia/ malignancy as each of their evaluation by cumbersome and painful scalpel biopsy procedure is often impractical. Early diagnosis of dysplasia/ malignancy helps patient to aim for curative treatment. Though cytomorphological difference between high grade dysplasia and carcinoma is not very distinct, certain features like high grade nuclear pleomorphism, presence of high frequency of micronuclei, tumor diathesis and bizarre shaped cells like tadpole, spindle shape etc. are the features which are more significantly associated with malignancy.