[Pathologic tumor volume predicting survival outcomes of patients with local advanced glottic carcinoma]

Objective:The aim of this study was to evaluate the predicting role of tumor volume as evaluated by postoperative pathologic examination on overall survival（OS） and disease free survival（DFS） in patients with local advanced glottic carcinoma. Methods:In this study, the records of 406 consecutive patients with local advanced glottic carcinoma（T3-T4 stages） who underwent surgery ± chemoradiotherapy from January 2005 to December 2010 were retrospectively reviewed and followed up. The demographic characteristics, disease staging, and pathologic tumor volume were analyzed. The optimal cutoff values of tumor volume for OS and DFS were obtained by using receiver operating characteristic（ROC） curves. The association of tumor volume with T stages were assessed by using Logistic regression model, and the relationship between tumor volume and OS and DFS rates were evaluated by using Cox regression models. Results:The 5-and 10-year OS rates were 62.9% and 55.4%, respectively. The 5-and 10-year DFS rates were 55.5% and 50.8%, respectively. The mean tumor volume was（5.1±6.7） cm³, T4 stage patients had higher tumor volume than those of patients with T3 stage（P<0.001）. The factor of tumor volume was correlated with T stages by using Logistic regression analyses（OR=13.81, 95%CI: 6.03-31.59, P<0.001）. The optimal cutoff values of tumor volume that were both at 3 cm³ for OS and DFS rates were obtained by using ROC curve plots. The OS and DFS rates of glottic carcinoma patients with tumor volume ≤ 3 cm³ were better when compared with those of patients with tumor volume>3 cm³（P<0.001）. Upon multivariate analyses, tumor volume was strongly correlated with poorer OS and DFS rates and remained independent prognostic factors for both the OS and DFS of patients with glottic carcinoma（OS: HR=1.59, 95%CI: 1.09-2.32, P＝0.017; DFS: HR=1.54, 95%CI: 1.08-2.20, P=0.016）. Conclusion:This study demonstrates that tumor volume is correlated with T stages, and this factor is an independent predictive factor of survival outcomes in patients with local advanced glottic carcinoma.