Subclinical syringoma coexisting with basal cell carcinoma.

We report three cases of clinically unapparent syringoma found incidentally on horizontal frozen tissue sections from patients undergoing Mohs micrographic excision of basal cell carcinoma (BCC). In the first case, the syringoma and BCC were admixed; in the other two cases, they were seen in close approximation to one another. In all cases, the tumors were detected on the faces of elderly women. The potential existence of a benign syringoma in association with BCC should be borne in mind, particularly in connection with Mohs micrographic excision. These tumors must be distinguished from one another in order to avoid excessive surgery beyond adequate resection of the basal cell carcinoma.