Background: Uterine carcinosarcoma (UCS) is a rare tumor with a poor prognosis. An elevated thrombocyte count and thrombocytosis were found to be associated with poor prognosis in several gynecological tumors. Data regarding an elevated thrombocyte count and thrombocytosis, particularly in UCS, are scarce.

Objectives: To assess the frequency of a preoperative elevated thrombocyte count and of thrombocytosis in UCS patients and their association with clinicopathological prognostic factors and survival.

Methods: The preoperative thrombocyte count of 29 consecutive verified USC patients diagnosed in our medical center from January 2000 to July 2015 was recorded, and clinicopathological data of these patients were abstracted from hospital files. 

Results: Thrombocytosis was found in two patients (6.8 %) and both died of the disease. An elevated thrombocyte count was found in nine patients (31.0%). The percentage of patients with the poor prognostic factors who had a preoperative elevated thrombocyte count was not statistically different from those without these risk factors. The cumulative survival of patients with an elevated count was 22.1 months and that of those without an elevated count was 31.1 months. This difference was statistically not significant (P = 0.85). There was also no difference between the groups regarding the progression free survival.

Conclusions: No association between an elevated thrombocyte count and prognosis was found. Larger studies are needed to clarify this issue.