Prognostic impact of pretreatment thrombocytosis in epithelial ovarian cancer

Aims: This study was aimed at investigating the prognostic impact of pretreatment thrombocytosis in epithelial ovarian cancer (EOC) patients in Lagos, Nigeria. Methods: This was a retrospective cohort study involving the review of the clinical record of 72 patients with histologically confirmed EOC who were managed at the Lagos University Teaching Hospital, Lagos, Nigeria over a 7-year period from January 2010 to December 2016. Information on the sociodemographic data and platelet counts at diagnosis of EOC were retrieved from the patients' medical records. Descriptive statistics were then computed for all baseline patients' characteristics. Survival analyses were carried out using the Kaplan-Meier estimates. Multivariate analysis of these data was performed with the Cox proportional hazards model. Results: This study revealed that the prevalence of pretreatment thrombocytosis was 41.7% among the women with EOC. Fifty-three (73.6%) of the women had the advanced-stage disease (FIGO stage III-IV) while 52 (72.2%) had high-grade disease (II-III). The majority (66.7%) of the women had a serous histological type of EOC while 76.4% had documented recurrence. Pretreatment thrombocytosis was significantly associated with the women's parity (P = 0.009), serum carbohydrate antigen 125 levels (P = 0.018), median progression-free survival (PFS) (P < 0.001), 3-year median overall survival (OS) (P < 0.001), type of primary treatment (P = 0.002), extent of cytoreduction (P < 0.001), presence of ascites (P = 0.002), International Federation of Gynecology and Obstetrics (FIGO) stage (P = 0.008), and histological type (P = 0.011). Pretreatment thrombocytosis was negatively associated with PFS (hazard ratio [HR] = 0.25; 95% CI 0.83, 0.75; P = 0.014) and 3-year OS (HR = 0.03; 95% CI 0.03, 0.27; P = 0.002). Conclusions: The study suggests that pretreatment thrombocytosis may be a useful predictor of survivals in EOC patients.