An Analysis of 20 Cases of Radiation-Associated Sarcoma, Including 4 Cases Treated by Carbon Ion Radiotherapy

Abstract

Introduction Radiation-associated sarcoma (RAS) is one of the most life-threatening complications associated with the treatment of malignant neoplasms. Because all RAS patients have a history of radiotherapy, there have been no effective treatment options when RAS is not completely resected. Methods We retrospectively reviewed 20 RAS patients, including 4 unresectable cases treated by carbon ion radiotherapy (CIRT). Results The primary diseases targeted by radiotherapy included malignant lymphoma (n=4), cervical cancer (n=3), pharyngeal cancer (n=3), breast cancer (n=2), lung cancer (n=1), rectal cancer (n=1), maxillary cancer (n=1), synovial sarcoma (n=1), and benign neoplasms (n=4). The histological diagnoses of RAS included osteosarcoma (n=8), leiomyosarcoma (n=3), undifferentiated pleomorphic sarcoma (n=3), rhabdomyosarcoma (n=1), angiosarcoma (n=1), malignant peripheral nerve sheath tumor (n=1), spindle cell sarcoma NOS (n=1), and sarcoma not further specified (n=2). The median survival time from the diagnosis of RAS was 26 months. Eleven patients underwent surgery. Five of these patients achieved a continuous disease free status or showed no evidence disease. Four patients underwent CIRT. One of these patients with leiomyosarcoma achieved a continuous disease free status, and the other patient with osteosarcoma achieved a partial response. On the other hand, 2 patients experienced Grade 3 toxicities that required surgical treatment. Conclusion RAS originates from various types of diseases that are treated by radiotherapy and shows diverse pathological features. Complete resection achieves a good prognosis. CIRT can be an effective and feasible option for unresectable RAS.

Management of Soft Tissue Sarcoma

“…An examination of 20 instances of radiation-induced sarcoma, which includes four instances that were treated using carbon ion radiotherapy, the histological diagnoses of RAS included leiomyosarcoma, undifferentiated pleomorphic sarcoma, rhabdomyosarcoma, angiosarcoma, malignant peripheral nerve sheath tumor, and spindle cell sarcoma, not otherwise specified [22]. The copy number patterns of sarcomas characterized by a simple genome (top) and sarcomas characterized by a complex genome (bottom), as determined using a next-generation sequencing platform.…”