To define who are good candidates for extraperitoneal cystectomy.

Between April 2009 and April 2012, 136 consecutive patients (median age 63.8 years, range 35-87 years) scheduled for transperitoneal radical cystectomy were included in this study. After the bladder was removed, the peritoneum covering the bladder was detached. Any suspicious macroscopic abnormalities on the peritoneum were sampled and examined. A 6-8 point random biopsy of the peritoneum was performed for patients without gross macroscopic abnormality.

The study group consisted of 41 patients with pT1, 48 patients with pT2, 34 patients with pT3, and 13 patients with pT4. The transitional cell carcinoma (TCC) group consisted of 123 of 136 patients (90.4%) and nonurothelial histologies of 13 of 136 patients (9.6%). In general, 8 of 136 patients (5.9%) and 14 of 816 biopsies (1.7%) were confirmed positive for peritoneum biopsies. Among them, 0 of 89 patients with pT1/2, 5 of 34 patients with pT3 (14.7%), and 3 of 13 patients with pT4 (23.1%) had positive biopsies (P <.001). In addition, 5 of 123 patients (4.9%) with TCC, 1 of 7 patients (14.3%) with adenocarcinoma, 1 of 2 patients (50%) with sarcomatoid carcinoma, and 1 of 2 patients (50%) with small cell tumors had positive peritoneum biopsies (P = .006). Among patients with positive lymph nodes, 5 of 34 patients (14.7%) had positive biopsies, compared with 3 of 102 patients (2.9%) in the lymph node-negative group (P = .012).

We found that tumor stage and lymph node status are independent predictors of peritoneal involvement. Extraperitoneal cystectomy should be performed with great caution, only indicated for those patients who have a high likelihood of stage pT1 and pT2. However, patients with cT2-4, positive lymph nodes, or nonurothelial histologies should not have the peritoneum covering the bladder preserved.