Background: Preoperative hyponatremia and thrombocytosis are associated with perioperative morbidity in patients with epithelial ovarian cancer (EOC). The aim of the present study was to evaluate preoperative hyponatremia and thrombocytosis as prognostic parameters in patients with EOC.
Methods: In a retrospective cohort study, serum levels of sodium and thrombocyte counts were evaluated in 498 patients with EOC. Data were extracted from the prospectively maintained database. Results were correlated with clinicopathological parameters and patient survival.
Results: Mean (standard deviation) overall pretherapeutic serum sodium levels and thrombocyte counts in patients with EOC were 138.8 (2.9) mmol/l and 340.1 (122.6) × 103/µl, respectively. Hyponatremia (serum sodium levels ≤ 134 mmol/l) was found in 33 (6.7%) patients and thrombocytosis (thrombocytes ≥ 450/µl) in 88 (17.7%) patients. Serum sodium levels were associated with the presence or absence of residual tumor tissue after primary surgery. Thrombocyte counts were associated with Fédération Internationale de Gynécologie et d'Obstétrique (FIGO) tumor stage, presence/absence of residual tumor, histological grade and histological type. Patients with thrombocytosis presented with advanced tumor stage, a higher rate of postoperative residual tumor mass, higher tumor grade, and a higher rate of serous ovarian cancer. In a multivariate logistic regression analysis, only the established clinicopathological parameters but not serum sodium and thrombocyte count were independent predictors of patient overall survival.
Conclusion: Preoperative hyponatremia and thrombocytosis are not useful as additional independent prognostic parameters in patients with EOC.
Keywords: Hyponatremia; Ovarian cancer; Platelet count; Serum sodium; Survival.