The impact of perivesical lymph node metastasis on clinical outcomes of bladder cancer patients undergoing radical cystectomy.

Background: Perivesical lymph nodes (PVLNs) are occasionally isolated during grossing of cystectomy specimens. However, the prognostic implications of the involvement of PVLNs in bladder cancer patients, especially those with comparisons to pN0 disease, remain poorly understood.

Methods: A retrospective review identified 115 radical cystectomy cases where PVLNs had been histologically assessed. These cases were then divided into 4 groups - Group 1 (n = 76): PVLN-negative/other pelvic lymph node (non-PVLN)-negative; Group 2 (n = 5): PVLN-positive/non-PVLN-negative; Group 3 (n = 17): PVLN-negative/non-PVLN-positive; and Group 4 (n = 17): PVLN-positive/non-PVLN-positive.

Results: pT stage at cystectomy was significantly higher in Group 3 (P = 0.013), Group 4 (P < 0.001), Groups 2 and 4 (P < 0.001), or Groups 2-4 (P < 0.001) than in Group 1. However, the number of positive PVLNs (mean: 1.8 vs. 2.1; P = 0.718) or the rate of extracapsular extension in the PVLNs (40% vs. 65%, P = 0.609) was not significantly different between Group 2 and Group 4. Kaplan-Meier analysis and log-rank test revealed significantly (P < 0.05) higher risks of disease progression (Group 3/Group 4), cancer-specific mortality (Group 2/Group 3/Group 4), and overall mortality (Group 4), compared with Group 1. Multivariate analysis further showed metastasis to both PVLN and non-PVLN (Group 4), PVLN (Groups 2 and 4), or PVLN and/or non-PVLN (Groups 2-4) as an independent prognosticator for cancer-specific mortality and overall survival. There were also insignificant (P = 0.096) and significant (P = 0.036) differences in cancer-specific survival and overall survival, respectively, between Group 3 versus Group 4, and the trend of the latter was confirmed by subset multivariate analysis (hazard ratio = 3.769; P = 0.099).

Conclusions: Worse prognosis was observed in bladder cancer patients with isolated PVLN metastasis (vs. pN0 disease especially for cancer-specific survival), PVLN metastasis with or without non-PVLN metastasis (vs. pN0 disease), and concurrent PVLN and non-PVLN metastases (vs. PVLN-negative/non-PVLN-positive disease especially for overall survival). These findings indicate the importance of thorough histopathological assessment of PVLNs in radical cystectomy specimens.