Prognostic value of platelet-associated biomarkers in rectal cancer patients received neoadjuvant chemoradiation: A retrospective study.

Purpose: Platelet volume has been shown to prognostic value in patients with colorectal cancer. However, the changes of other platelet-associated biomarkers in rectal cancer patients, before and after the neoadjuvant chemoradiation therapy (NACRT), remain unclear. In this study, we investigated the prognostic value of platelet-associated biomarkers in rectal cancer patients with NACRT.

Patients And Methods: A total of 75 patients with locally advanced (T3-4 or N+) rectal cancer (LARC) cancer were selected and followed up from the Affiliated Cancer Hospital of Zhengzhou University between June 2013 and September 2016. The data of platelet-associated biomarkers, including the platelet count, platelet to lymphocyte ratio (PLR), lymphocyte to monocyte ratio (LMR), mean platelet volume (MPV), and platelet distribution width (PDW) both pre- and post- NACRT, were collected. The associations between these platelet-associated biomarkers and the overall survival (OS), as well as disease-free survival (DFS) of patients, were analysed. Patients were divided into groups with high or low values of the platelet-associated biomarkers, and the outcomes were compared by using Cox regression and Kaplan-Meier analysis.

Results: We found that pre-PLR (HR: 4.104; 95%CI: 1.411-11.421; P=0.009) and pre-LMR (HR: 0.384; 95%CI: 0.124-1.185; P=0.066) could predict the OS in LARC patients after NACRT by multivariate Cox regression analysis, a cut-off value of pre-PLR>7.02 and pre-LMR ≤7.10 could be used as independent prognostic factors for OS by Kaplan-Meier method. The pre-MPV value could be used as an independent prognostic factor for DFS by Kaplan-Meier analysis (P=0.037). Moreover, post-CEA was correlated with OS and DFS in LARC patients with NACRT.

Conclusion: In LARC patients with NACRT, the pre-PLR and pre-LMR are independent prognostic factors for OS, while pre-MPV has predictive value for DFS.