70-Year-Old Male with a Slow Growing Painless Nodule on the Scalp

Abstract

Alopecia neoplastica (AN) is a rare subtype of scarring alopecia that is caused by metastasis from underlying malignancies, most frequently from primary visceral tumors such as in breast tissue. AN presents more frequently in women but has a poorer prognosis when diagnosed in men. The clinical presentation of patients affected with AN consists of nodular red-violaceous lesions in the frontoparietal scalp with or without scaling. Although AN most commonly occurs after the diagnosis of the primary tumor, diagnosis of AN may be challenging especially if its onset occurs prior to the primary tumor diagnosis. The histological findings of AN consist of the metastatic carcinoma cells infiltrating into the dermis and subcutaneous tissue, fibrosis of the dermis and subcutaneous tissue, the loss of pilosebaceous units, and the pleomorphic cellular morphology that is typical of adenocarcinoma. The proposed mechanism of AN involves the release of cytokines from metastatic carcinoma cells leading to fibrosis and destruction of pilosebaceous units. The identification of skin metastases plays a role in staging and treatment of the disease, making it vital to identify them early. Treatment of AN is primarily focused on systemic treatment for the primary tumor. Although case reports of regrowth are present, patients should be counseled on the scarring nature of the hair loss as well as the generally poorer prognosis associated with AN.