Treatment of basal cell carcinoma with 13-cis-retinoic acid.

: Patients with basal cell carcinoma were treated locally with 13-cis-retinoic acid. Disappearance of the tumors was observed in two of fifteen patients. Thirteen patients whose tumors diminished after the treatment were finally managed surgically. Biopsy specimens were examined histopathologically and by autoradiography. Treated tumors showed reduction of labeling indices as compared with the nontreated group.