Perioperative blood transfusion and ovarian cancer survival rates: A meta-analysis based on univariate, multivariate and propensity score matched data.

The negative impact of perioperative blood transfusion on survival outcomes has been reported in several cancer types. The purpose of the present study is to summarize existing evidence in ovarian cancer patients. We searched the Medline, Scopus, Clinicaltrials.gov, EMBASE, Cochrane Central Register of Controlled Trials CENTRAL and Google Scholar databases for observational and randomized trials that assessed the impact of perioperative blood transfusion on the disease-free survival (DFS) and overall survival (OS) of ovarian cancer patients that undergone debulking surgery were selected for inclusion. The methodological quality of the included studies was assessed by using the Newcastle-Ottawa Scale. Statistical meta-analysis was performed with the RevMan 5.3 software using the Der-Simonian Laird random effects model. Seven studies were identified which included 2341 ovarian cancer patients. Meta-analyses that were based on univariate and multivariate reporting revealed that perioperative blood transfusion had a significant negative impact on the patient`s OS rates (OR 1.78, 95 %CI 1.16, 2.74 and OR 1.31, 95 %CI 1.00, 1.71 respectively). Disease free survival rates were also influenced according to the results of the univariate analysis (OR 1.58, 95 %CI 1.14, 2.19), however, the effect was not significant in the multivariate analysis. The analysis that was based on propensity score matched populations did not reveal differences among transfused and non-transfused. Concluding, the findings of our meta-analysis suggest that transfusion of blood products during the perioperative period is not an independent factor that may affect survival outcomes of ovarian cancer patients. Nevertheless, it should be noted that patients that receive transfusion have several potential confounders that may affect their survival outcomes.