482 Pretreatment thrombocytosis and ovarian cancer survival: a meta-analysis

Introduction/Background Thrombocytosis has been associated with cancer progression and decreased survival rates in various forms of cancer. The purpose of this study is to evaluate the impact of pre-treatment thrombocytosis on ovarian cancer survival. Methodology We searched Medline, Scopus, Clinicaltrials.gov, Cochrane Central Register of Controlled Trials CENTRAL for studies that reported survival outcomes of ovarian cancer patients with pretreatment thrombocytosis and compared them to those of patients with normal platelet counts were considered eligible. The study was registered in PROSPERO prior to its onset (Registration number: CRD42023433037). Statistical meta-analysis was performed with RStudio using the meta function. Results Fourteen articles were retrieved that included 5,414 ovarian cancer patients. The methodological quality of included studies ranged between moderate and high. Patients with advanced stage disease were more likely to establish pre-treatment thrombocytosis and its presence was associated with lower rates of optimal debulking. Thrombocytosis was also associated with increased odds of ovarian cancer recurrence (HR 2.01, 95% CI 1.34, 3.01) and a higher risk of death from the disease (HR 2.29, 95% CI 1.35, 3.90). The incidence of deep vein thrombosis was comparable in both groups (OR 1.62, 95% CI 0.48, 5.46). Conclusion Pre-treatment thrombocytosis is associated with increased risk of recurrence and death of ovarian cancer patients. It is a potential sign of advanced stage disease and might be predictive of suboptimal tumor debulking during surgery. Its association with other factors that affect survival, including platinum resistance and response to targeted therapy remains poorly explored, although preliminary data suggest a potential correlation. Disclosures The authors report no conflicts of interest.