Bladder
Adjuvant pelvic RT re-enters the post-cystectomy conversation on randomised locoregional data, not survival.
BART
ForPost-cystectomy MIBC, pT3-4 / pN+ / R+, chemo-treated, no adjuvant IO
87.1% vs 76.0%
HR 0.43, 95% CI 0.20-0.96, p=0.04
TL;DR2yr LRFFS 87.1% vs 76.0% with adjuvant pelvic RT after cystectomy, HR 0.43 (0.20-0.96), p=0.04; OS unchanged.
Reported via UroToday →
The RT read is the per-protocol and subgroup magnitude: LRFFS HR 0.27 (0.10-0.71) among those actually irradiated, and HR 0.22 (0.06-0.75) in pN+. Target was cystectomy bed plus full pelvic nodes to 50.4Gy/28fx with stoma-sparing IMRT, a plan deliverable in standard practice, and late G3+ toxicity was 8.4% vs 10.5%. That moves the offer-RT decision for pN+ disease.
In pN+ or pT3-4 urothelial MIBC after cystectomy and cisplatin-based chemotherapy, this supports discussing adjuvant pelvic RT for locoregional control; it does not inform pts receiving adjuvant nivolumab, who were unrepresented here.
The deliverable read is technique plus magnitude: 50.4Gy/28fx to cystectomy bed and full pelvic nodes with stoma-sparing IMRT and daily IGRT, late G3+ 8.4% vs 10.5%, LRFFS HR 0.22 (0.06-0.75) in pN+. This moves the offer-adjuvant-RT decision for pN+ or margin-positive disease.
Chemotherapy was neoadjuvant in 71% and adjuvant in 20%, and no pt received immunotherapy, so this speaks to a failure mode the chemo backbone did not cover: 26% locoregional recurrence under observation. It does not change regimen choice, but it questions whether adjuvant nivolumab alone addresses pelvic failure.
With a median 20 nodes dissected and a 4.6% positive margin rate, locoregional recurrence still reached 26% without RT, so this is not attributable to inadequate surgery. For pT3-4, pN+, or R+ specimens, it argues for referral for adjuvant RT discussion rather than surveillance alone.
12 details 2 trials watching
Phase III multicenter RCT, 1:1 adjuvant radiotherapy versus observation, N=153 accrued 2016-2024 (RT 77, observation 76). Stratified by nodal stage (N0 vs N+) and chemotherapy timing. Median follow-up 47 months; per-protocol comparison by log rank, with Fine-Gray competing-risk subdistribution HRs for LRFFS (competing risks distant metastases, non-cancer death) and DFS.
High-risk non-metastatic urothelial MIBC post radical cystectomy: T3-4, N1-3, or R+. 62% pT3-T4, 41% pN+, variant histology component in 28%. Median age 57, median nodes dissected 20, positive margin rate 4.6%, neobladder in 2.6%.
Chemotherapy was neoadjuvant in 71% and adjuvant in 20%; 9.2% received none. No patient received immunotherapy in either arm.
50.4Gy in 28 fractions to the cystectomy bed and pelvic nodes. CTV covered common iliac, internal and external iliac, presacral and obturator nodes plus the cystectomy bed. Stoma and bowel sparing IMRT with daily onboard image guidance. 63 of 77 allocated received planned RT.
Primary: 2-year locoregional failure-free survival. Secondary: bladder cancer-specific survival, disease-free survival, overall survival.
Primary endpoint met. Overall 37% recurred, 18% locoregionally (8% RT vs 26% observation, p=0.006), and there were no isolated locoregional recurrences in the RT arm. Survival endpoints all favored RT numerically without reaching significance.
| Endpoint | Adjuvant RT | Observation | Effect size |
|---|---|---|---|
| LRFFS (primary) | 87.1% | 76.0% | HR 0.43 (0.20-0.96), p=0.04 |
| LRFFS per protocol | 93.2% | 75.0% | HR 0.27 (0.10-0.71), p=0.008 |
| DFS | 71.6% | 58.7% | HR 0.62 (0.36-1.05), p=0.07 |
| Bladder cancer-specific survival | 79.6% | 65.0% | HR 0.59 (0.33-1.10), p=0.09 |
| Overall survival | 70.4% | 57.4% | HR 0.78 (0.49-1.26), p=0.31 |
Grade 3 GI events were low and no higher with RT (1.6% vs 4.1%); the cost was grade 2 GI (17.5% vs 1.4%) with no toxicity-related discontinuation. Late grade 3+ toxicity was similar (8.4% vs 10.5%, p=0.60).
The comparator that defines current adjuvant practice is CheckMate 274 (adjuvant nivolumab), which no BART patient received, so this addresses a locoregional failure mode nivolumab was never shown to control. Prior adjuvant RT evidence in this space is the smaller Egyptian NCI randomised experience; BART is described as the largest RCT here.
Accrual over eight years fell short of target, so the survival endpoints are underpowered rather than negative: the OS CI (0.49-1.26) is compatible with both a substantial benefit and modest harm. 14 of 77 allocated to RT never received it and were analyzed with observation (n=90), which is the per-protocol comparison the headline HR 0.27 comes from.
This establishes that pelvic RT after cystectomy does what RT does elsewhere: it controls the field it treats, at an acceptable late-toxicity cost. What it does not establish is whether preventing a locoregional recurrence in a disease this systemically aggressive translates into survival, which the planned MERCY IPD meta-analysis is meant to answer.
CONSORT flow
Randomised, primary endpoint met, prespecified stratification. Adjuvant RT is not standard post-cystectomy; this is the first positive phase III. Underpowered for OS, no IO backbone.
- Does locoregional control translate into an overall survival benefit active Adjuvant Radiotherapy in Patients With Pathological High-risk Bladder Cancer (GETUG-AFU 30) Phase NAn=81 · primary completion 2027-12 · randomised adjuvant pelvic RT post-RC + PLND
- Adjuvant radiotherapy combined with adjuvant immunotherapy recruiting Adjuvant Concurrent Immunotherapy and Radiotherapy for the Treatment of Bladder Cancer Phase 1n=10 · primary completion 2027-04 · phase 1 concurrent adjuvant IO + RT safety
- Generalizability to older pts with limited lymphadenectomy