[Evaluation of thrombocytosis as predictive factor in colorectal cancer]

INTRODUCTION/AIM OF THE STUDY: Preoperative thrombocytosis proved to be a negative prognostic factor in several solid tumor. However, there is still debate in the literature regarding colorectal cancer. The aim of our study was to examine whether thrombocytosis is an independent risk factor for metastasis development and predictor of survival in colorectal cancer.

Clinicopathological data of 336 patients with colorectal cancer (CRC) and 118 patients with liver metastasis of colorectal cancer (mCRC) who had operation between 2001 and 2011 were collected retrospectively. Thrombocytosis was defined as 400 G/L < platelet count. Disease-free survival (DFS) and overall survival (OS) were determined with Kaplan-Meier method supported by log-rank test.

Both in the CRC and the mCRC group OS was significantly shorter in patients who had elevated platelet count (HR = 2.2, p < 0.001 and HR = 2.9, p = 0.018, respectively). Multivariate analysis confirmed that elevated platelet count was an independent prognostic factor of both CRC (HR = 1.7, p = 0.035) and mCRC (HR = 3.1, p = 0.017). DFS was significantly shorter in patients with elevated platelet count in the CRC group (HR = 2.0, p = 0.011).

The platelet count is a valuable and cheap prognostic marker for the prediction of survival in patients both with CRC and mCRC.