Preliminary analysis of efficacy and safety of intensity-modulated radiotherapy for stage IV_A thymoma

Objective: To preliminarily evaluate the efficacy and safety of intensity-modulated radiotherapy (IMRT) in the treatment of inoperable stage IV_A thymoma. Methods: A retrospective analysis of 15 patients with inoperable stage IV_A thymoma receiving IMRT from January 2010 to December 2017 was performed. Among them, 9 patients were male and 6 female, aged 31-83 years with a median of 59 years. The dose of radiotherapy was 50 Gy/60 Gy/70 Gy/ 15-20 fractions for PTV/CTV/GTV. The short-term efficacy, overall survival rate and adverse reactions were analyzed. Results: The follow-up rate was 100%. The median follow-up time was 48 months. The short-term partial remission rate was 93%(14/15). The 1-, 3- and 5- year overall survival rates were 100%, 75% and 75%, respectively. One patient presented with grade 3 hematological reaction. Four patients died of tumors. Conclusion: Preliminary findings demonstrate that IMRT is an efficacious and safe treatment of stage IV_A thymoma, which can be applied for patients with unresectable thymoma. (authors)