Clinical significance of preoperative thrombocytosis in patients who underwent radical nephrectomy for nonmetastatic renal cell carcinoma

PURPOSE The aim of this study was to examine the association of preoperative thrombocytosis with the prognosis of patients with nonmetastatic renal cell carcinoma (RCC). MATERIALS AND METHODS We conducted a retrospective analysis of 187 patients who underwent a radical nephrectomy for nonmetastatic RCC between July 1997 and June 2009. Thrombocytosis was defined as a platelet count≥400,000 µL, and patients were divided into 2 groups according to presence of preoperative thrombocytosis, and the cancer-specific survival rates and overall survival rates of the 2 groups after radical nephrectomy were compared. RESULTS The mean age of the patients was 56.0±11.7 years and the mean follow-up period was 59.3±42.1 months; there were 20 patients with preoperative thrombocytosis. Thirty patients developed metastases and 9 patients died during the follow-up period. In Kaplan-Meier analysis using a univariate log-rank test, both cancer-specific survival rate (p=0.013) and overall survival rate (p=0.012) showed significant association with preoperative thrombocytosis. Controlling for pathological TNM stage, Fuhrman grade and tumor diameter, the Cox proportional hazards model for cancer-specific survival rates showed that preoperative thrombocytosis was an independent prognostic factor (p=0.025). CONCLUSIONS Preoperative thrombocytosis was associated with poorer prognosis in patients with nonmetastatic RCC. Thus, preoperative platelet count may be clinically useful for risk stratification of patients undergoing surgery for nonmetastatic RCC.