Real-world management and outcome of thymic carcinomas in a tertiary German center

BackgroundThymic carcinomas are an aggressive subset of thymic epithelial tumors with considerable heterogeneity and limited therapeutic options. Data about the management of patients with metastatic disease in the real-world setting are scarce.MethodsWe retrospectively analyzed the clinical course of patients with thymic carcinomas diagnosed until October 2020 at the Thoraxklinik Heidelberg. For patients diagnosed before 1994, tumor stages were reclassified from the Masaoka to the Masaoka-Koga system using data from the patient records.ResultsOverall, 200 cases were identified with an average age at initial diagnosis of 56 years (range 16-90 years), and a predominance of males (64%). Stage according to Masaoka-Koga was I-II for 29 (14.5%), III for 48 (24%), and IV for 123 patients (stage IVA 14%, and stage IVB 86%). The rate of surgery decreased with more extensive disease spread and was 97% (28/29) for stages I-II (the single exception received only radiotherapy (RT) due to comorbidities), 88% (42/48) for stage III, 47% (8/17) for stage IVA, and 41% (43/106) for stage IVB. The majority of patients in any stage received RT, namely 62% in case of stage I-II, 73% in case of stage III, and 51% in case of stage IV. Chemotherapy (CHT) was given to 29% stage III, and 78% stage IV patients. Median overall survival (OS) was 13.9 years (95% confidence interval 5.1-22.7) for stage I-II, 8.7 (5.7-11.6) years for stage III, 7.3 (2.7-11.8) years for stage IVA, and 3.6 (2.1-5.1) years for stage IVB. Multivariable analysis showed that CHT, RT and surgery were all significantly and independently associated with longer OS for stage IV disease (hazard ratio (HR)=0.52 with p=0.025 for CHT, HR=0.53 with p=0.014 for RT, and HR=0.45 with p=0.001 for surgery, respectively). Stage IV patients treated with CHT only (n=40) or RT only (n=7) had worse outcome, but nevertheless a median OS exceeding 2 years (2.2, 95% CI 1.7-2.6, and 2.3, 95% CI 0-5 years, respectively).ConclusionsLife expectancy of patients with thymic carcinomas varies widely according to the tumor stage and exceeds 10 years for disease without infiltration into neighboring organs. For metastatic tumors, multidisciplinary management including a combination of CHT, RT and surgery whenever possible, significantly prolongs survival.Legal entity responsible for the studyThoraxklinik Heidelberg.FundingDeutsches Zentrum für Lungenforschung (=DZL).DisclosureAll authors have declared no conflicts of interest.