The use of cytology in the diagnosis of basal cell carcinoma.

Two hundred and forty patients with basal cell carcinomas (BCCs) on the head or neck were studied. Scrapings of the lesions were taken for cytological examination, and a 3-mm punch biopsy was performed for histopathological study. The accuracy of diagnosis by each method was compared. Both methods confirmed the clinical diagnosis in 226 cases, and both were negative in 10 cases. Cytopathology gave one false negative result (0.42%), and histopathology gave two false negative results (0.83%). Cytopathology gave one false positive result (0.42%), and histopathology did not produce any false positive results. We conclude that cytological examination of skin scrapings from suspected BCCs is a rapid and reliable method of diagnosis.