Are volume-dependent parameters in positron emission tomography predictive of postoperative recurrence after resection in patients with thymic carcinoma?

This study aimed to investigate the association between the volume-dependent parameters in 18F-fluorodeoxyglucose-positron emission tomography (18F-FDG PET/CT) and a recurrence of thymic carcinoma. A retrospective chart review was performed based on our multi-institutional database to identify patients undergoing PET prior to resection of thymic carcinoma or neuroendocrine carcinoma between 1991 and 2018. The PET parameters (metabolic tumor volume and total lesion glycolysis) were evaluated retrospectively. The relevant factors were extracted and a survival analysis was performed using the Kaplan-Meier method. Sixteen patients were thus deemed to be eligible for analysis. The median follow-up period following resection was 2.65 years (range: 0.96-0.68 years). The recurrence-free survival was significantly longer in patients with a metabolic tumor volume < = 22.755 cm3 and with total lesion glycolysis < = 105.4006 g/mL (p = 0.001 and 0.001, respectively, by a log-rank test). The metabolic tumor volume and total lesion glycolysis may, therefore, be predictive of the postoperative recurrence of thymic carcinoma.