[Cytodiagnosis of benign, precancerous and malignant skin changes].

Smears of the keratinizing squamous epithelium were taken from various parts of the body of 252 patients. The conditions sampled were 28 inflammatory lesions, 51 benign tumors, 31 mildly precancerous lesions, 34 seriously precancerous lesions, 42 basal cell carcinomas, and 38 squamous cell carcinomas. In addition, we examined smears of 28 healthy controls. The specimens were evaluated according to cytomorphological criteria of malignancy previously described for vulvar lesions. We made use of a modified Papanicolaous's classification. About 18% of the benign lesions proved falsely positive; 16% of the mildly precancerous lesions, 3% of the seriously precancerous lesions, and 3% of the invasive carcinomas proved falsely negative. The material collected was insufficient for diagnosis in about 10% of the cases. Aside from punch biopsy, the cytological investigation of cutaneous lesions may be a valuable technique regarding the early diagnosis of cancer and precancer of the skin.