Abstract 218P
Background
Thymic epithelial tumors are rare malignancies that arise in the prevascular mediastinum. The Masaoka-Koga (MK) staging system is traditionally used for staging. In 2017 the 8th edition of TNM classification was published and is gaining acceptance.
Methods
A retrospective study of all patients who underwent surgery for thymoma between 2011 and 2022 at our institute. Kaplan-Meier survival analysis was used to calculate overall survival.
Results
Among 125 patients identified, 62 were men (50%). Median age was 52.8 years. 45 patients (36%) were diagnosed with myasthenia gravis during the course of the disease. Frequency of B2 thymoma was much higher in our cohort compared to previous studies (N = 65, 52%). According to MK staging system there were 50 stage I (40%), 47 stage IIa/b (∼37%), 21 stage III (∼16%) and seven stage IVa/b (5.5%). After re-staging according to the 8th edition TNM staging classification, all MK stage II patients were down staged to stage I. Eight patients were down staged from stage III – six to stage II and two to stage I. Both MK and TNM staging systems were associated with overall survival. 5-year survival was 94% and 10-year survival was 89%. Tumor size, histology and myasthenia gravis were not correlated with survival. Recurrences were seen as late as 8 years following surgery.
Conclusions
This is the first Israeli surgical series of patients with thymoma in recent years. Re-staging according to the 8th edition TNM staging caused significant down staging of tumors.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
D. Urban: Financial Interests, Personal, Invited Speaker: Merck, Sharpe & Dohme, Takeda, Roche Israel, Rhenium/Oncotest, Bristol Myers Squibb, AstraZeneca. H. Gantz Sorotsky: Financial Interests, Personal, Invited Speaker: Roche-Genentech, MSD, AstraZeneca, Takeda, Astellas, BMS, Pfizer, Medison, Novartis, Boehringer Ingelheim International. E. Marom: Financial Interests, Personal, Invited Speaker: AstraZeneca, Boehringer Ingelheim, Merck Sharp & Dohme. J. Bar: Financial Interests, Personal, Advisory Board: AbbVie, AstraZeneca, Bayer, BMS, Causalis, MSD, Novartis, Roche, Takeda; Financial Interests, Personal, Research Grant: Immunai, OncoHost, MSD, AstraZeneca. All other authors have declared no conflicts of interest. The author has declared no conflicts of interest.