Risk factors for intraoperative cyst rupture in partial nephrectomy for cystic renal masses

To determine the risk factors of intraoperative cyst rupture in partial nephrectomy (PN) for a cystic renal mass (CRM) and their effect on the prognosis of patients.

Patients who underwent partial nephrectomy for CRMs from January 2009 to January 2015 were included. Uni/multivariate Logistic/Cox analysis and Kaplan-Meier analysis were performed.

A total of 174 patients were included in this study. There were 27 (15.5%) intraoperative cyst ruptures. The median follow-up time was 60 months. Multivariate logistic analysis showed that the E component (P = 0.018) and N component (P = 0.022) of the R.E.N.A.L. nephrometry score, Bosniak category III (P = 0.044), and surgeon's experience (P = 0.030) were risk factors associated with intraoperative cyst rupture in PN for CRMs. The 5-year recurrence-free survival (RFS), cancer-free survival (CFS) and overall survival (OS) were 92.7%, 90.32% and 94.4%, respectively, in 124 cases of malignant CRM. Kaplan-Meier analysis demonstrated that 5-year RFS and 5-year CFS in patients with cyst rupture was worse than those without cyst rupture (P = 0.006 and 0.003, respectively). Multivariate Cox analysis revealed that intraoperative cyst rupture was independent risk factor for 5-year RFS and 5-year CFS (P = 0.039 and 0.013, respectively). However, there was no significant difference in OS between the two groups (P = 0.275).

The prevalence of intraoperative cyst rupture is relatively high. Higher E and N scores, Bosniak category III, and lacking surgical experience (<20 cases) increase the risk of occurrence of intraoperative cyst rupture.