Risk Factors For Intraoperative Cyst Rupture In Partial Nephrectomy For Cystic Renal Masses

Purpose This study aimed to determine the risk factors associated with intraoperative cyst rupture in partial nephrectomy for a cystic renal mass(CRM)and their effect on the prognosis of patients.Materials and Methods Patients who underwent partial nephrectomy for CRMs(Bosniak category: IIF,III,IV)from January 2009 to January 2015 were included in this retrospective study.Univariate and multivariate logistic regression analyses were used to determine the risk factors for intraoperative cyst rupture in partial nephrectomy.Survival analysis was performed by using Kaplan–Meier and Log-rank analysis.Clinicopathological features and prognostic factors were analyzed using univariate and Multivariate Cox regression analyses.Results A total of 174 patients included in this study were classified into two groups according to the prevalence of intraoperative cyst rupture: Intraoperative cyst rupture(n = 27)and No intraoperative cyst rupture(n=147);The rate of intraoperative cyst ruptures is 15.5%.Multivariate analysis showed that the E component(HR=3.150,95% CI 1.214-8.174,P=0.018)and N component(HR=2.383,95% CI 1.132-5.017,P=0.022)of the R.E.N.A.L.nephrometry score,Bosniak category III(HR=5.429,95% CI 1.048-28.131,P=0.044),and surgical experience(HR=7.083,95% CI 1.210-44.459,P=0.03)were risk factors associated with intraoperative cyst rupture in partial nephrectomy for CRMs.Postoperative histologic findings were malignant malignant cystic renal mass in 124 cases.All patients were operated successfully and were followed up for 26–60 months.A total of 13(7.47%)patients died including three(1.72%)in the cyst rupture group and 10(5.75%)in the no cyst rupture group.The time interval to recurrence was significantly shorter in the intraoperative cyst rupture group compared with the no intraoperative cyst rupture group(P=0.006).However,there was no significant difference in overall survival between the two groups.Univariate analysis demonstrated age,the prevalence of intraoperative cyst rupture,maximum tumor size,pathological stage and Furhman grades were associated with 5-year recurrence-free survival(RFS)and overall survival(OS).Multivariate Cox regression analysis showed that the prevalence of intraoperative cyst rupture was the independent risk factor of the recurrence of CRM(HR=6.007,95%CI 1.099-32.850,P=0.039).However,there was no significant difference between intraoperative cyst rupture and OS(P=0.085).Conclusions The prevalence of intraoperative cyst rupture is relatively high.Higher E and N scores,Bosniak category III,and a lack of surgical experience(less than 20 cases)increase the risk of occurrence of intraoperative cyst rupture.Intraoperative cyst rupture is the independent risk factor of the recurrence of CRM.However,intraoperative cyst ruptures was no related to OS in patients underwent PN for CRM.