Perineural invasion by transitional cell carcinoma of the bladder in patients submitted to radical cystectomy: what is the prognostic value?

OBJECTIVE Determine the prognostic value of perineural invasion (PNI) in patients with transitional cell carcinoma (TCC) of the bladder treated with radical cystectomy. MATERIALS AND METHODS From January 1993 to January 2005, 113 people were selected from 153 patients with TCC of the bladder treated with radical cystectomy. The association between the presence of PNI and other pathologic characteristics were analyzed through Fisher exact test. The Kaplan-Meier method was utilized to assess the survival curve and the statistical significance was determined by the Breslow test. The multivariate analysis was performed through the Cox regression model. RESULTS The PNI was identified in 10 (8.8%) of the 113 patients. This variable significantly related to the microvascular invasion and to tumor staging. The mean segment after surgery was 31.7 +/- 28.5 months. Recurrence occurred in 5 (50%) and in 41 (39.8%) patients (p=0.363) and mortality occurred in 2 (20%) and 22 (21.9%) patients (p=0.606) with or without PNI respectively. In Cox regression analysis, patients with PNI presented with 1.53 times (IC 95% 0.60 to 3.91; p=0.371) and 1.60 times (IC 95% 0.37 to 6.95; p=0.532) the risk of recurrence and mortality when compared to patients without PNI. CONCLUSIONS The PNI does not constitute an independent variable of disease-free and cancer specific survival in patients with TCC of the bladder treated with radical cystectomy.