Metastatic Spiradenocarcinoma Managed With PD-1 Inhibition.

Spiradenomas are rare skin adnexal tumors, usually benign, appearing in early adulthood. The etiology of this tumor is still debated. The tumor suppressor gene CYLD, responsible for the Brooke-Spiegler syndrome, causes spiradenomas, trichoepitheliomas, and cylindromas. With time, spiradenomas can degenerate into aggressive spiradenocarcinomas. With only 117 malignant cases reported, treatment recommendations are based on case reports and expert opinion. There is no standard of care beyond surgical resection for localized disease and no guidelines for management of metastatic disease. With the advent of immunotherapy and PD-1 inhibition, we present the first reported case of a metastatic spiradenocarcinoma managed with pembrolizumab.