I'm seeing a 66 y/o M with muscle invasive bladder cancer who underwent radical cystectomy prior to seeing me. He did not receive neoadjuvant therapy. Surgical path showed papillary urothelial carcinoma, high-grade extending into the inner half of the muscularis propria, negative margins -- pT2N0. NCCN mentions adjuvant cisplatin-based chemo if >pT3, and nivo if they had >ypT2 after neoadjuvant therapy. Do you typically offer any adjuvant therapy in this situation?
I would discuss adjuvant chemotherapy in this situation, although ultimately would not necessarily recommend using it. Data suggests patients with pT2N0 bladder cancer have a relatively lower risk of recurrence with 5- and 10-year recurrence-free survival of 89% and 78%: https://pubmed.ncbi.nlm.nih.gov/11157016/. There have not been clean/robust datasets to look at the benefit of adjuvant chemotherapy in this setting. Meta-analysis showed DFS benefit and marginal OS benefit with adjuvant cisplatin-based chemo with MIBC, but there were challenges with accrual/statistics with some of the trials included in that meta-analysis. EORTC 30994 was the largest randomized study to look at adjuvant chemo and included ~20% of patients with pT2 disease; the overall study showed DFS benefit without OS benefit, but the pT1-T2 subgroup analysis for OS did not seem to favor adjuvant chemo (with the obvious caveat of it being an under-powered subgroup analysis). I would not recommend use of adjuvant nivolumab in this situation, since CheckMate 274 did not include such patients, especially given the study has shown only DFS benefit without OS benefit so far. Based on the cumulative data available, I would discuss the use of adjuvant chemo for MIBC and that while there is certainly some risk of recurrence with pT2N0 disease, the overall risk is relatively low and there is lack of robust evidence to show that adjuvant therapy significantly helps to reduce recurrence risks.
