[Radiation-associated sarcomas of bone and soft tissue: a clinicopathological analysis of 46 cases]

Objective: To investigate the clinical, imaging, histological, and molecular features and the differential diagnosis of radiation-associated sarcomas of bone and soft tissue. Methods: Forty-six cases of radiation-associated sarcomas of the bone and soft tissue in Beijing Jishuitan Hospital from January 2010 to January 2022 were retrospectively analyzed; and the imaging, histological features and immunophenotype were examined. Results: There were 33 females and 13 males, aged from 18 to 74 years, with a mean of 52 years. The most common site of radiation-associated sarcomas were the limbs and spine (15 cases), followed by the chest (9 cases). The primary diseases included epithelial tumors (15 breast cancer, 6 cervical cancer, and 5 bowel cancer), hematolymphoid tumors, bone and soft tissue tumors and infectious lesions. The latent period of radiation-associated sarcomas ranged from 2-22 years, with an average of 11.6 years. Histopathologically, the morphology was divergent from the primary tumor. The most common malignant tumor type was undifferentiated sarcoma (22 cases), followed by osteosarcoma (16 cases). The immunophenotype of radiation-related sarcoma was almost the same as the corresponding soft tissue sarcoma. Conclusions: Radiation-induced sarcoma has a wide range of primary tumor types and its imaging, morphology and immunohistochemical features are similar to those of the primary sarcoma of bone and soft tissue. Clinical correlation is often recommended for the differential diagnosis.