Muir-Torre syndrome: a case of this uncommon entity.

A 69-year-old Hispanic woman presented for the evaluation of nodules on the head and back. In the past, she had been treated for basal cell carcinoma (BCC) of the face; the referring physician was concerned that the new lesions might also be BCC. The patient had an extensive past medical history. In addition to BCC, she had been treated for breast cancer, colon cancer, and cervical cancer prior to emigrating to the USA. Her colonic malignancy had been localized proximal to the splenic flexure. She also had a history of colonic polyps and distal colonic villous adenoma. She denied ever being treated with radiation. Further details of her medical history and cancer staging were not available. Her family history was significant for a sister with colon cancer and transitional cell carcinoma of the urinary bladder. In addition, she had a great aunt with oral cancer and a great uncle with lung cancer. Neither the patient or her relatives had any history of tobacco use. On physical examination, in addition to scars from a radical mastectomy and midline abdominal laparotomy, four skin lesions were noted: two on the scalp, one on the tragus, and one on the mid-back. The first lesion on the vertex of the scalp was a yellow-brown waxy papule measuring 0.6 x 0.5 cm. This lesion was similar to that on the mid-back, except in size. The lesion on the back measured 1.2 x 1.0 cm. The second lesion on the frontal scalp measured 0.8 x 0.6 cm and was red-brown with a pearly appearance and some central hyperkeratosis. The tragus lesion was similar in appearance to that on the frontal scalp. Shave biopsies of all lesions were obtained. The lesions on the scalp and mid-back revealed lobules of sebaceous cells in the dermis with a minority of surrounding basaloid cells, consistent with a diagnosis of sebaceous adenoma (Fig. 1). Although the lesion on the frontal scalp also showed sebaceous differentiation, there were a greater number of basaloid cells, some with hyperchromatic nuclei and mitotic figures; this was consistent with a diagnosis of sebaceous epithelioma (Fig. 2). The final lesion (tragus) was histologically consistent with a keratotic BCC. No further treatment was required for these benign sebaceous tumors, but their presence defined our patient's condition as Muir-Torre syndrome. Mohs' micrographic surgery was performed on the tragus BCC and the margins were tumor free in one stage. The patient returned 1 year later with a lesion anterior to the left axilla which was biopsied to rule out BCC (Fig. 3). Histologically, this lesion was also consistent with sebaceous epithelioma.