Prognostic Factor in Patients with Advanced, Inoperable Thymic Carcinoma: An Application of the Lung Immune Prognostic Index

Background: The prognostic implications of palliative chemotherapy for advanced or recurrent thymic carcinomas require full elucidation. The lung immune prognostic index (LIPI) is a novel prognostic index whose effectiveness has recently been reported in lung cancer patients. This study aimed to evaluate the LIPI’s clinical value in advanced or recurrent thymic carcinoma patients. Methods: : We retrospectively analyzed 41 advanced or recurrent thymic carcinoma patients undergoing palliative chemotherapy between January 2001 and December 2020. Survival-time analysis was conducted using the Kaplan–Meier method and log-rank test. Multivariate analysis using the Cox proportional hazards model was performed to investigate the LIPI’s predictive and/or prognostic value. Results: : Median progression-free survival (PFS) for first line chemotherapy and overall survival (OS) were significantly longer in the good-LIPI group (LIPI: 0) than in the intermediate/poor-LIPI group (LIPI: 1 or 2) (PFS: 13.4 vs. 6.8 months, p=0.0425; OS: 48.2 vs. 28.9 months, p=0.00506.). Multivariate analysis revealed that serum albumin <3.5 g/dL and an intermediate/poor LIPI were independent adverse prognostic factors for OS. Moreover, an intermediate/poor LIPI was the only adverse prognostic factor for PFS. Conclusions: : Our study indicates that the LIPI is a potential prognostic marker in patients with advanced or recurrent thymic carcinoma undergoing palliative chemotherapy.