Mohs Surgical Extirpation of a Basal Cell Carcinoma in a Patient with Familial Multiple Trichoepitheliomas

Abstract

BACKGROUND. The success of Mohs surgery relies on the ability to histologically differentiate tumor from the normal background tissue of the patient. In most cases of basal cell carcinoma and nonmelanoma skin cancer, this is a relatively straightforward process. However, in distinction, when only subtle histopathologic features differentiate the background tissue from the tumor of interest, the determination of a tumor-free margin becomes more challenging.

Atypical Adnexal Tumors Adjacent to Basal Cell Carcinoma: A Difficult Problem in Patients with Brooke-Spiegler Syndrome Undergoing Mohs Surgery

“…A prior MMS report for BCC in a patient with multiple familial trichoepitheliomas described successful differentiation of the BCC from surrounding trichoepitheliomas using features seen in H&E sections such as epithelial-stromal clefting, presence of follicular differentiation, and varying size of tumor aggregations to differentiate the two types of tumors. 3 Individuals with BSS can have tumors with conflicting histopathologic features, and in our case, assessment with immunostaining by two dermatopathologists did not reveal a definitive diagnosis. Heterogeneity in such tumors may give a false impression of malignancy or benignancy when only a small portion of the tumor is visualized.…”

“…1,2 Mohs micrographic surgery (MMS) has been used to treat such challenging tumors, relying on the differing histopathologic features of BCC and trichoepithelioma to guide margin assessment. 3 Routine histopathologic assessment of adnexal tumors usually permits clear distinction between benign and malignant neoplasms. Immunostaining sometimes can assist in difficult cases, but even with immunostaining, a small number of tumors have overlapping benign and malignant features, which makes an exact diagnosis difficult.…”

Tricoepitelioma múltiple

“…Su evolución es por brotes; generalmente persiste de por vida, aunque algunos casos muestran involución o se ulceran. Se ha relacionado con los cilindromas (Cilindromatosis familiar o S. Brooke-Spiegler) (2,3). Existe controversia en cuanto a su eventual transformación en carcinoma basocelular (está documentado el desarrollo de carcinoma basocelular en áreas afectadas por tricoepitelioma) (4-6), sin embargo, no hay investigaciones rigurosas al respecto para saber si estos pacientes muestran mayor susceptibilidad que la población general.…”