Superficial (pT2a) and deep (pT2b) muscle invasion in pathological staging of bladder cancer following radical cystectomy

The purpose of this retrospective study is to evaluate the prognostic significance of superficial (pT2a) and deep (pT2b) invasion of bladder muscle, after radical cystectomy and urinary diversion for transitional cell carcinoma. From 1971 to 2001, 311 of 1,359 patients (23%) were found to have pathological muscle invasive (pT2) bladder cancer following radical cystectomy; 147 patients (47%) had pT2a (superficial) and 164 (53%) had pT2b ( deep). 127 patients with pT2a (86%) and 115 with pT2b had no evidence of lymph node metastasis. 20 patients with pT2a (14%) and 49 with pT2b (30%) had positive lymph nodes. Median followup of these patients was 14.3 years (range 0 to 30.1). The 10-year recurrence-free and overall survival rates for 311 patients with pT2 tumors were 72% and 47%, respectively. For pT2b tumors, the risk of node positive disease was higher than pT2a tumors (30% versus 14%, p < 0.001). If lymph nodes were negative no significant difference was found in 10-year recurrence-free survival in patients with pT2a and pT2b tumors (84% versus 72%, p = 0.091). No significant difference was observed in 10-year recurrence-free survival (50% versus 48%, p = 0.84) between pT2a lymph node positive versus pT2b lymph node positive tumors. Recurrence-free survival was significantly higher in patients with pT2 lymph node negative tumors than in those with pT2 lymph node positive tumors (% 79 versus % 49 p<0.001) The risk of lymph node positivity is higher for patients with deep muscle (pT2b) tumors than superficial (pT2a) tumors. There is no apparent difference in recurrence-free survival between pT2a (superficial) versus pT2b (deep) muscle invasive tumors when controlling for lymph node status. Patients with muscle invasive (pT2), lymph node positive tumors tumors should be considered for adjuvant treatment protocols because of higher recurrence rates. Patients with muscle invasive (pT2), lymph node negative tumors have excellent outcomes following cystectomy.