Background: The predictors of overall survival (OS) and recurrence-free survival (RFS) for thymic carcinoma have not been well clarified. The prognostic significant of serum lactate dehydrogenase (LDH) level in thymic carcinoma remains unclear. So we evaluated the role of pretreatment serum LDH level in the prognosis for thymic carcinoma in this study.
Methods: Sixty consecutive surgical patients were enrolled in this study with pathologic confirmed thymic carcinoma in Sun Yat-sen University Cancer Center from June 1996 to June 2014. Clinical and pathologic data were retrospectively reviewed. Pretreatment serum LDH level was tested. Categorical variables were compared using the Chi-square test or Fisher’s exact test. Survival time was analyzed using the Kaplan-Meier method and log-rank test. Multivariate analysis was performed using the Cox proportional hazard model.
Results: The mean ± standard deviations (SD) pretreatment serum LDH level for this cohort were 214.12±107.85. The overall 1- 3-, 5-, and 10-year survival rate was 88.2%, 75.4%, 66.1%, and 62.8%, respectively. The 1- 3-, 5-, and 10-year RFS rate was 78.3%, 58.6%, 47.6%, and 34.8%, respectively. In both univariate analysis and multivariable analysis, only pretreatment serum LDH level (hazard ratio =2.749, P=0.027) and pathological Masaoka stage (hazard ratio =2.931, P=0.041) were associated with OS. In univariate analysis, pretreatment serum LDH level (P=0.004), tumor size (P=0.019), completeness of resection (P=0.010), postoperative radiotherapy (P=0.003) and pathological Masaoka stage (P=0.010) were associated with RFS. Multivariable analysis showed that pretreatment serum LDH level (hazard ratio =2.696, P=0.006), postoperative radiotherapy (hazard ratio =2.922, P=0.006) and pathological Masaoka stage (hazard ratio =2.768, P=0.036) were independently prognostic factors of RFS. This study also found that male patients and larger tumor size had a significantly higher rate of elevated pretreatment serum LDH level than in the other groups.
Conclusions: Pretreatment serum LDH level is an independent prognosis factor of OS and RFS, and could be a supplement for Masaoka stage.
