A Recurrence Predictive Model for Thymic Tumors and Its Implication for Postoperative Management: a Chinese Alliance for Research in Thymomas database study

Abstracts Introduction To investigate appropriate postoperative management based on the risk of disease recurrences in thymic epithelial tumors after complete resection. Methods The Chinese Alliance for Research in Thymomas (ChART) retrospective database was reviewed. Patients having stage I-IIIa tumors without pretreatment and with complete resection were included. Clinico-pathological variables with statistical significance in the multivariate Cox regression were incorporated into a nomogram for building a recurrence predictive model. Results Nine-hundred-and-seven cases were retrieved, including 802 thymomas, 88 thymic carcinomas, and 17 neuroendocrine tumors between 1994 and 2012. With a median follow-up of 52 months, 10-year overall survival (OS) was 89.5%. Distant and/or loco-regional recurrences were noted in 53 (5.8%) patients. The nomogram model revealed histologic type and T stage as independent predictive factors for recurrence, with a bootstrap-corrected C-index of 0.86. Based on this model, patients with T1 thymomas or T2-3 Type A/AB/B1 thymomas had significantly lower incidence of recurrence (low-risk group) than those with T2-3 Type B2/B3 thymomas and all thymic carcinomas/neuroendocrine tumors (high-risk group, 2.7% vs. 20.1%, p Conclusions A 6-year active surveillance should be considered in high-risk patients regardless of adjuvant therapy. For low-risk patients, annual follow-up may be sufficient. Studies on post-operative adjuvant therapies would be plausible in high-risk patients.