Melanoma Within Basal Cell Carcinoma Nests Discovered During Mohs Micrographic Surgery.

A65-year-oldCaucasianwomanpresentedwith a lesion present for 6 months on the left anterior shoulder. A recent biopsy showed “probable metatypical carcinoma.” The patient had Fitzpatrick Type II skin, brown hair, hazel eyes, and freckling. She reported a lifetime of moderate sunexposure in SouthernCalifornia averaging 3 to 5 hours per day. Her medical history included 2 melanomas on the left arm 1 year prior, a basal cell carcinomaonthe left alar crease2yearsprior, andcancer of the left breast. The breast cancer was diagnosed in 2006 as ductal carcinoma in situ with cancer negative nodes. She received treatment with lumpectomy and radiation followedbyArimidex (anastrozole) for 5 years and has not had a recurrence.