Pulmonary angiomyolipoma and multifocal micronodular pneumocyte hyperplasia associated with tuberous sclerosis

A 36-year-old woman with a long-standing diagnosis of tuberous sclerosis was found dead. A yellow-tan 0.4 cm-diameter pulmonary tumor was identified at autopsy which had typical microscopic features of an angiomyolipoma (AML). Immunohistochemical stains showed reactivity for actin, but not HMB-45, Melan-A, and tyrosinase (despite reactivity of the patient's renal AML for HMB-45 and Melan-A), perhaps owing to the small size of the lesion and the sometimes focal nature of the reactivity for these markers. Additional lung nodules proved to be multifocal micronodular pneumocyte hyperplasia. This report highlights the first occurrence of a pulmonary angiomyolipoma in the setting of tuberous sclerosis.