Phase II study of neoadjuvant chemotherapy with four cycles of dose-dense MVAC followed by radical cystectomy in Korean patients with muscle-invasive or locally advanced urothelial carcinoma of bladder.

PURPOSE

While previous retrospective or phase II studies in Western populations showed that dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin (ddMVAC) as neoadjuvant chemotherapy (NAC) was beneficial, no studies have been reported in Asian populations. This prospective phase II study aimed to evaluate efficacy and safety of ddMVAC in Korean patients with muscle-invasive bladder cancer (MIBC) or locally advanced urothelial cancer (UC).

MATERIALS AND METHODS

Patients with MIBC (cT2-4aN0M0) or locally advanced UC (cTanyN1-3M0) eligible for radical cystectomy (RC) were enrolled prospectively. The participants were treated with four cycles of ddMVAC with pegfilgrastim every 2 weeks. The primary endpoint was pathologic response rate (≤ypT1N0). Secondary endpoints were pathologic complete response (pCR, ypT0N0), relapse-free survival (RFS), overall survival (OS), and safety.

RESULTS

Among 24 patients enrolled between December 2019 and August 2021, 23 were evaluable (52%, cT2-4aN0; 48%, cTanyN1-3). Eighteen patients (78%) completed four cycles of ddMVAC, while remaining five patients experienced early discontinuation. Dose modification (91%) and dose delay (70%) occurred, and the dose intensity of ddMVAC was 79%. Nineteen patients underwent RC and four patients declined. Of 19 patients who underwent RC, eight patients (42%) achieved ≤ypT1N0. With a median follow-up of 22.8 months, the median RFS was 13.5 months (95% CI, not yet evaluable) and the median OS was 28.9 months (95% confidence interval, 19.9-37.9).

CONCLUSION

Our study showed substantial efficacy and safety of ddMVAC, even in patients with locally advanced UC. The ddMVAC still should be a promising option as NAC in Asian patients with UC.