Preoperative Thrombocytosis and Poor Prognostic Factors in Endometrial Cancer

This study aimed to evaluate the prevalence of preoperative thrombocytosis and its prognostic significance in Thai patients with endometrial cancer. We retrospectively reviewed the medical records of 238 cases who had undergone surgical staging procedures between January 2005 and December 2008. Associations between clinicopathological variables and preoperative platelet counts were analyzed using Pearson's chi square or two-tailed Fisher's exact tests. Survival analysis was performed with Kaplan-Meier estimates. Univariate and Cox-regression models were used to evaluate the prognostic impact of various factors including platelet count in terms of disease-free survival and overall survival. The mean preoperative platelet count was $315,437/{\mu}L$ (SD $100,167/{\mu}L$). Patients who had advanced stage, adnexal involvement, lymph node metastasis, and positive peritoneal cytology had significantly higher mean preoperative platelet counts when compared with those who had not. We found thrombocytosis (platelet count greater than $400,000/{\mu}L$) in 18.1% of our patients with endometrial cancer. These had significant higher rates of advanced stage, cervical involvement, adnexal involvement, positive peritoneal cytology, and lymph node involvement than patients with a normal pretreatment platelet count. The 5-year disease-free survival and overall survival were significantly lower in patients who had thrombocytosis compared with those who had not (67.4% vs. 85.1%, p=0.001 and 86.0% vs. 94.9%, p=0.034, respectively). Thrombocytosis was shown to be a prognostic factor in the univariate but not the multivariate analysis. In conclusion, presence of thrombocytosis is not uncommon in endometrial cancer and may reflect unfavorable prognostic factors but its prognostic impact on survival needs to be clarified in further studies.