INTRODUCTION: In the course of anastomotic insufficiency following resection of esophageal cancers the bacterial compound of the esophageal substance has a remarkable, presumable role in the outcome of complications. AIM: The purpose of this study is to compare the consequences of the anastomotic leak with the bacterial flora of patients' oral cavity. METHOD: In this prospective study a total of 131 patients were investigated directly before the surgical intervention taking a bacterial sample. Bacterial flora of patients' oral cavity was analysed; and the correlation between the consequences of the anastomotic leak and the content of the bacterial flora was examined. RESULTS: Pathogenic bacteria in the oral microflora in 50 cases (38.2%) was found. Statistically significant, moderate correlation was found between the severity of the complication and the incidence of pathogenic bacteria (rs = 0.553; p</=0.05). CONCLUSIONS: Pathogenic agent in the microbial flora might induce higher risk and more severe outcome in case of anastomotic leakage and it might be evaluated as a determinative factor. Consideration of the bacterial flora of the oral cavity requires more attention in the preoperative preparation than before and it demands the change of the current practice. Orv. Hetil., 2017, 158(1), 25-30
