Thymoma radiotherapy: a retrospective multicentre study

Abstract

Aims: In this study, we aimed to evaluate the outcomes of thymoma patients who underwent radiotherapy (RT). Methods: Data from thymoma patients who underwent RT at Ankara Bilkent City Hospital, Ankara Atatürk Education and Research Hospital and Ankara Numune Education and Research Hospital were analysed retrospectively. The primary endpoints of this study were acute and late side effects and the secondary endpoints were overall survival(OS) and disease-free survival(DFS). Results: Data from 22 patients who received RT between 10.03.2008 and 05.10.2022 were analysed.The median follow-up time was 33 months (range: 1–76). RT-related acute toxicity was observed in 6 patients(27.3%). Late RT-related toxicity was noted in 4 patients (18%). As a late toxicity one patient (4.5%) had a secondary malignancy five years after RT.Patients younger than 40 years of age had significantly higher acute (p=0.039) and late (p=0.01) toxicity. Recurrence was observed in 7 patients (31.8%). The median DFS was 13 months (range: 1–176),the 1-year DFS was 58%, the 5-year DFS was 23%. Lower DFS was observed in patients with myasthenia gravis (MG) (p=0.018). Six patients(27.3%) died, the median OS was 33 months (range: 1–176),the 1-year OS was 84.4%, the 5-year OS was 76.7%. There was a significant correlation between performans status and OS (p=0.047). Conclusion: Side effects were more frequently observed in patients younger than 40 years of age. Poor prognostic factors were identified as MG for DFS and poor performance status for OS. Thymoma patients have high OS, studies are needed to identify subgroups that do not require RT.

Keywords

• Thymic epithelial tumours
• radiotherapy
• thymic carcinoma
• thymoma

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