Postradiation Sarcoma From a Free Flap

Abstract

Postradiation sarcomas constitute approximately 0.5% to 5.5% of all sarcomas. They develop locally approximately 3 to 20 years after the administration of radiotherapy (RT). They are generally high-grade tumors. Osteosarcomas, fibrosarcomas, malignant fibrous histiocytoma, angiosarcomas, and leiomyosarcomas are the most frequently observed. It is rare for these tumors to originate from free flaps, and this patient report is one of the first in the literature. A 59-year-old man was operated on because of ethmoid sinus cancer in 2004, and the reconstruction was performed with a rectus abdominis free muscle flap. He received postoperative RT and subsequently presented to our clinic with a medially protruding mass on his upper jaw. A biopsy was performed. Its pathologic diagnosis was reported as malignant mesenchymal tumor. Computed tomography and magnetic resonance imaging were performed, demonstrating that the mass originated from the free muscle flap (m. rectus abdominis) at the front wall of the sphenoid sinus. A total excision of the free muscle flap and near-total maxillectomy were performed. The pathologic finding was reported as leiomyosarcoma with bone invasion. With the advancement of medical and pharmaceutical technologies, our patient's life expectancy is increasing. In long-living patients who have received RT, tumors can develop 20 years after the RT. The close follow-up of patients receiving RT is of utmost importance because treatment survival is linked to early diagnosis and resection with negative surgical margins. We must not forget that, even if years have passed since receiving RT, these patients may present with such tumors.