Cutaneous Pleomorphic Rhabdomyosarcoma Occurring on Sun-Damaged Skin: A Case Report

Rhabdomyosarcoma (RMS) is a malignant soft tissue tumor with skeletal muscle differentiation that can rarely present as a primary cutaneous tumor. There are 3 main subtypes of RMS: embryonal, alveolar, and pleomorphic. Primary cutaneous pleomorphic RMS is extremely rare, there being only 9 reported cases in the literature, 2 of which are radiation induced. We present a case of primary pleomorphic RMS occurring on the sun-damaged skin of the face of an 89-year-old woman. The tumor was diagnosed by histology, immunohistochemistry, and electron microscopy. The patient was treated by surgery and adjuvant radiotherapy. The tumor recurred rapidly after surgical excision. She died 2 months after the diagnosis from complications of treatment, local symptoms of tumor, and concurrent illnesses. Primary cutaneous pleomorphic RMS is a rare tumor of adults and pursues an aggressive clinical course.