ESTRO 2025 - Abstract Book

S1663

Clinical - Sarcoma & skin cancer & malignant melanoma

ESTRO 2025

505

Poster Discussion Treatment options for cardiac sarcoma? Insights from a population-based study Yiqun Han, Meng Xu Welliver Radiation Oncology, Mayo Clinic, Rochester, USA

Purpose/Objective: To investigate the relationship of clinicopathological characteristics and treatment options to survival outcomes for cardiac sarcoma. Material/Methods: Data on sarcoma patients from 2000 to 2020 were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. Cardiac sarcomas confirmed through histology were identified, of which data representing clinical features and survival outcomes, including overall survival (OS) and cancer-specific survival (CSS), were extracted. Survival outcomes were compared using the Kaplan-Meier method with log-rank tests, while prognostic factors were identified through COX regression analysis. Results: A total of 219 patients with cardiac sarcoma was identified in this study. Most tumors originated from the heart (84.5%, 185/219); others were metastasized from other sites (15.5%, 34/219). Of the 219 cases, 42.9% (94/219) were classified as histologic grade 4, while 15.5% (34/219) were grade 3 and 6.0% (13/219) were grade 1-2. Median OS of the entire population was 10 months (range: 10-16 months), while the CSS was 19 months (range: 14-25 months). The incidence of brain metastasis at diagnosis was 2.3% (5/219); the presence of brain metastasis independently correlated to both OS (HR 2.94; 95%CI 1.04-8.35, P =0.042) and CSS (HR 4.81; 95%CI 1.28-18.12, P =0.02). Favorable prognostic factors for OS and CSS included treatments with surgery and/or chemotherapy. There was no significant association between radiotherapy and either OS or CSS. Interestingly, tumor size greater than 5cm was not associated with CSS but favorably associated with OS. Distant metastasis negatively affected CSS. Surgery and chemotherapy significantly prolonged both OS (HR surgery 0.50; 95%CI 0.33-0.76, P =0.001; HR chemotherapy 0.56; 95%CI 0.39-0.79, P =0.001) and CSS (HR surgery 0.43; 95%CI 0.27-0.71, P =0.001; HR chemotherapy 0.65; 95%CI 0.43-0.97, P =0.034) of patients with cardiac sarcomas. Radiation therapy did not result in a significant difference in OS (HR radiotherapy 0.73; 95%CI 0.47-1.13, P =0.161) or CSS (HR radiotherapy 0.86; 95%CI 0.52-1.44, P =0.573). There was no significant difference in survival outcomes among radiotherapy alone, radiotherapy in combination with surgery or chemotherapy, or the triplet therapy. Conclusion: Cardiac sarcoma is a rare but aggressive disease. This retrospective study found that the presence of brain metastasis at the time of diagnosis was associated with worse survival. Patients showed notable survival benefits from surgery and/or chemotherapy, while the data did not show clear benefit from radiotherapy. Notably, new technologies such as proton therapy or cardiac motion management could result in different outcomes. Additional studies are warranted to validate these findings in the future.

Keywords: cardiac sarcoma, survival outcomes