Identification and validation of risk factors for vesicourethral leaks following radical retropubic prostatectomy

Aims: To identify risk factors for anastomotic leaks at cystography following radical retropubic prostatectomy (RRP). Methods: In phase 1 the records of a 107 RRP patients were reviewed. Data collected included comorbidity, pathological factors and intra- and postoperative complications. From these, risk factors were identified that were associated with a leak at cystography. In phase 2 (n = 46) we prospectively tested if the risk factors identified could predict an anastomotic leak. Results: In phase 1 the only identifiable risk factors were that of a difficult anastamosis, an unsatisfactory intraoperative test flush and the presence of a urinary tract infection. One or more of these events were found in 17/25 (68%) of the patients who leaked (P < 0.0001). Of the eight leaks missed, five were classed as minimal and did not require repeat cystography. Within the prospective phase 2 cohort one or more risk factors were present in 7/10 (70%) of the patients who leaked. In contrast, the identified risk factors were present in only 5/36 (13.8%) of the patients who did not leak (P < 0.001). The specificity of the test was 86.1% with a sensitivity of 70%. This gave a positive predictive value of 58.3% and a negative predictive value of 91.1%. Three leaks (two minimal and one moderate) would have been missed but 31 (67.3%) patients would have avoided an unnecessary radiological study. Conclusion: Using a retrospective and prospective cohort of patients we have shown that a cystogram following RRP can be safely avoided in the absence of the identified risk factors.