Cytologic and DNA-cytometric early diagnosis of oral cancer

Objective. The aim of this prospective study was to report on the diagnosti c accuracy of conventional oral exfoliative cytology taken from white-spott ed, ulcerated or other suspicious oral lesions in our clinic. In addition w e checked DNA-image cytometry as an adjuvant diagnostic tool. Our hypothesi s is that DNA-aneuploidy is a sensitive and specific marker for the early i dentification of tumor cells in oral brushings. Study design. 251 cytologic al diagnoses obtained from exfoliative smears of 181 patients from macrosco pically suspicious lesions of the oral mucosa and from clinically seemingly benign oral lesions which were exisiced for establishing histological diag noses were compared with histological and/or clinical follow-ups of the res pective patients. Additionally nuclear DNA-contents were measured after Feu lgen restaining using a TV image analysis system. Results. Sensitivity of o ur cytological diagnosis on oral smears for the detection of cancer cells w as 94.6%, specificity 99.5%, positive predictive value 98.1% and negative p redictive value 98.5%. DNA-aneuploidy was assumed if abnormal DNA-stemlines or cells with DNA-content greater 9c were observed. On this basis the prev alence of DNA-aneuploidy in smears of oral squamous cell carcinomas in situ or invasive carcinomas was 96.4%. Sensitivity of DNA-aneuploidy in oral sm ears for the detection of cancer cells was 96.4%, specificity 100%, positiv e predictive value 100% and negative 99.0%. The combination of both techniq ues increased the sensivity to 98.2%, specificity to 100%, positive predict ive value to 100% and negative to 99.5%. Conclusions. Brush cytology of all visible oral lesions, if they are clinically considered as suspicious for cancer, are an easily practicable, cheap. non-invasive, painless. safe and accurate screening method for detection of oral precancerous lesions, carci noma in situ or invasive squamous cell carcinoma in all stages. We conclude that DNA-image cytometry is a very sensitive, highly specific and objectiv e adjuvant tool for the early identification of neoplastic epithelial cells in oral smears.