Thrombocytosis at secondary cytoreduction for recurrent ovarian cancer predicts suboptimal resection and poor survival.

OBJECTIVES: A growing body of evidence supports a role for thrombocytosis in the promotion of epithelial ovarian cancer biology. However, studies have only linked preoperative platelet count at time of initial cytoreductive surgery to clinical outcome. Here, we sought to determine the impact of elevated platelet count at time of secondary cytoreductive surgery (SCS) for recurrent disease.

METHODS: Under an IRB-approved protocol, we identified 107 women with invasive epithelial ovarian cancer who underwent SCS between January 1997 and June 2012. We reviewed clinical, laboratory, and pathologic records from this retrospective cohort. The data was analyzed using the chi-squared, Fisher's exact, Cox proportional hazards, and Kaplan-Meier tests. We defined thrombocytosis as a platelet count ≥ 350 × 10(9)/L and optimal resection at SCS as microscopic residual disease.

RESULTS: Thirteen of 107 women (12%) with recurrent ovarian cancer had thrombocytosis prior to SCS. Preoperative thrombocytosis at SCS was associated with failure to undergo optimal resection (p=0.0001). Women with preoperative thrombocytosis at time of SCS demonstrated shorter overall survival (33 months) compared to those with normal platelet counts (46 months, p=0.004). On multivariate analysis, only preoperative platelet count retained significance as an independent prognostic factor (p=0.025) after controlling for age at SCS (p=0.90), disease free interval from primary treatment (0.06), and initial stage of disease (0.66).

CONCLUSIONS: Elevated platelet count at time of SCS is associated with suboptimal resection and shortened overall survival. These data provide further evidence supporting a plausible role for thrombocytosis in aggressive ovarian tumor biology.