Jumping to conclusions: Misdiagnosing radiation induced sarcoma as recurrent breast cancer

Radiation therapy (RT) induced chondrosarcoma is a rare but important potential complication seen in cancer patients treated with radiation. Although uncommon, these patients tend to have a poor prognosis, so early detection and complete resection are the crucial steps towards survival. We present the case of an 81-year-old breast cancer patient who was treated with RT to the left chest wall. Eight years later, she presented with a growing left chest wall mass, initially thought to represent local breast cancer recurrence. Imaging demonstrated a well-defined mass arising from the left pectoralis major muscle. The mass was excised, and pathology demonstrated chondrosarcoma. We discuss the clinical and radiologic aspects of RT-induced sarcomas with attention to the very rare chondrosarcoma. The aim of this report is to provide a succinct but relevant summary of the diagnostic considerations for RT-induced sarcoma supported by information about epidemiology, clinical diagnostic criteria, and radiation biology to expedite patient workup and ultimately improve patient outcomes.