Perivesical fat invasion in bladder cancer: implications for prognosis comparing pT2b, pT3a and pT3b stages and consequences for adjuvant chemotherapy indications

Study Type--Therapy (retrospective cohort) Level of Evidence 2b. What's known on the subject? and What does the study add? The more that bladder cancer progresses from the urothelium to the outside of the bladder the worse the prognosis. To date, the use of adjuvant chemotherapy has not been completely defined. The present study clarifies the prognosis and benefits of adjuvant chemotherapy for different stages of bladder cancer that invade perivesical fat.

Objective: • To assess the prognosis of pT2b, pT3a and pT3b bladder cancers after radical cystectomy (RC) in order to define potential situations where chemotherapy may be of benefit.

Patients and methods: • Between 1985 and 2009, 903 patients underwent a RC and pelvic bilateral lymphadenectomy in an Institutional Referral Centre. • In all, 87 patients (9.6%) had a pT2b tumour, 111 patients (12.3%) a pT3a tumour, and 129 patients (14.3%) a pT3b tumour. • The median (range) overall follow-up was 23 (1-350) months. • Overall (OS), disease-specific (DSS), metastases-free (MFS) and local recurrence-free survival (LRFS) was estimated and compared using Kaplan-Meier plots and log-rank test.

Results: • The 5-year survivals pT2b and pT3a were similar for LRFS (86% vs 84%), MFS (69% vs 63%), DSS (72% vs 70%) and OS (66% vs 61%), and the prognosis was better than for pT3b stage tumours (69%, 44%, 40%, and 31% respectively). • In pN0 disease, MFS differences between pT2b-pT3a and pT3b tumours were not significant in patients who had received adjuvant chemotherapy (MSF of 87%, 69% and 56%, respectively) while they were significant in patients without adjuvant chemotherapy (MFS of 70%, 68% and 42%, respectively).

Conclusions: • Bladder cancers invading perivesical tissue macroscopically have a greater propensity to produce lymph node metastases, local recurrence, and have lower MFS, DSS, and OS. In pN0 disease, pT3b tumours may receive more benefit from adjuvant chemotherapy. • Our results could be a useful for selecting patients for adjuvant chemotherapy.