Radiation-Induced Sarcoma in Patients With Nasopharyngeal Carcinoma

BACKGROUND: The increasing incidence of radiation-induced sarcoma (RIS) has become a significant problem that can limit long-term survival. The objective of the current study was to analyze the clinicopathologic characteristics, treatment outcomes, and prognostic factors of RIS after radiotherapy for nasopharyngeal carcinoma (NPC). METHODS: Institutional electronic medical records of patients with NPC who received definitive radiotherapy between February 1964 and 2003 were reviewed. Fifty-three patients who developed RIS and fulfilled the study criteria were included. RESULTS: The median follow-up after a diagnosis of RIS was 15.5 months (range, 0.4-90.3 months), and the median latency between radiotherapy for NPC and an RIS diagnosis was 9.3 years (range, 3.2-26.6 years). Fibrosarcoma was the most frequent histologic type observed, followed by osteosarcoma, and malignant fibrous histiocytoma. The 3-year overall survival (OS) rate for 49 patients who received treatment was 32.4%, and the median survival was 21.2 months (95% confidence interval, 8.7-33.8 months). The median OS was 41.3 months, 8.4 months, and 11 months for the complete resection group, the incomplete resection group, and the chemotherapy group, respectively (P<.0001). The only independent predictive factor that was associated with better OS was complete surgical resection. CONCLUSIONS: This retrospective study confirmed the rarity and poor prognosis of RIS in patients with NPC. Complete surgical resection was a significant prognostic factor for survival. The authors concluded that long-term follow-up is necessary for the early detection of RIS in patients with NPC. Cancer 2010;116:5479-86. (C) 2010 American Cancer Society.