Exfoliative cytologic examinations in the early diagnosis of oral cancer.

Oral cytology-in spite of the wide extension of the use of cytologic diagnostic methods in various branches of medicine was and is the subject of many controversies. Opinions concerning the reliability of oral exfoliative cytology differ but all agree upon one point, oral cytology is not a substitute for biopsy. The main value of oral exfoliative cytology seems to lie in the diagnosis of malignant tumours, but differs according to the stages of progression of the disease. Comparison of cytological and histological results in oral carcinomas according to various authors gave a false negative rate of between 0 and 31 per cent. Advanced oral carcinomas already arouse suspicion at clinical examination and indicate the need for a biopsy. Therefore, in spite of the frequent ulceration increasing the effectiveness of cytodiagnostics, the importance of exfoliative cytology in advanced tumours is diminished. Exfoliative cytology may act as an important diagnostic aid in early oral carcinomas with ulcerated surfaces, even in some clinically unsuspected cases malignancy can be detected. In multiple or extensive lesions the selection of the most suitable site for the biopsy is possible. In leukoplakia the effectiveness of cytology is still more subject to dispute, the rate of false negatives is reported as high as to 63-9 per cent. However, when taking the clinical type of leukoplakia into consideration, the erosive leukoplakias which are known to be more inclined to become malignant showed a 76-6 per cent reliability of cytodiagnosis.