Clinicopathological analysis and therapeutic management of radiation-induced sarcomas of the head and neck: A single-center retrospective study.

Abstract

e23537 Background: Radiation-induced sarcoma of the head and neck (RISHN) is a rare but devastating late toxicity of curative radiotherapy (RT). We conducted a single-center cohort study to analyze the clinicopathological characteristics, management, survival, and hemorrhagic risk of RISHN and to identify associated prognostic factors and effective clinical treatments. Methods: We conducted a retrospective analysis of 25 pathologically confirmed RISHN patients treated at Fudan University Shanghai Cancer Center (January 2019 to December 2025), constituting the largest single-institution case series to date. The clinical data include diagnostic age, RT dose, latency, RISHN site, histological subtype, stage, first symptoms and treatment. The survival analysis was estimated by the Kaplan–Meier method. Results: The median age at RISHN diagnosis was 47 years and the median latency was 10.7 months. The most common primary tumor was nasopharyngeal carcinoma (NPC, 21 cases, 84.0%), receiving RT doses ≥66 Gy. RISHN arose chiefly in paranasal sinuses and nasopharynx. Bleeding and nasal congestion were most common presenting symptoms. The Median follow-up time was 24.2 months. The major histological subtypes of RISHN included post-radiation sarcoma (11 cases), undifferentiated sarcoma (4 cases) and osteosarcoma (4 cases). Surgery was the cornerstone of initial management and gross total resection (GTR) was achieved in 11 patients. However, the median EFS was only 10.4 months with the 1-year EFS rate of 41.1%. GTR conferred a significant EFS benefit over nonGTR (incomplete resection or systemic therapy alone), with median EFS times of 12.9 versus 6.9 months (p=0.03; HR=0.34). The median OS was 28.3 months and a numerical advantage in median OS was observed for GTR group (36.9 months) over nonGTR group (20.0 months) (p=0.17, HR=0.40). In 18 patients receiving first-line systemic therapy, the disease control rate (DCR) was 83.4% and the median PFS was 7.7 months. Exploratorily, patients who received immunotherapy had numerically longer PFS (12.7 vs 6.0 months, p=0.53, HR=0.66) and OS (48.9 vs 28.3 months, p=0.99, HR=1.01) than those who did not. Hemorrhage was a notable clinical manifestation especially in anlotinib-treated RISHN patients, whereas none of six patients undergoing prophylactic carotid embolization experienced significant bleeding subsequently. Conclusions: RISHN had a poor prognosis. GTR was an independent prognosis predictor of RISHN, while the EFS was unsatisfactory. Systemic therapy offers an important treatment option. First-line treatment with immunotherapy may improve survival outcomes in RISHN patients. Hemorrhage mitigation, particularly careful use of anti-angiogenic therapy and selective prophylactic endovascular intervention, should be integrated into multidisciplinary care.