onc brain

Open-label, multicenter phase 3 RCT across 17 China hospitals; randomized 1:1, 77 pts per arm, stratified by clinical N stage (cN0 vs cN+). Primary pCR read by blinded independent central review.

pMMR/MSS rectal adenocarcinoma, cT3-4N0/+M0, tumor lower edge ≤10cm from the anal verge, ECOG 0-1, age 18-75, no positive lateral pelvic node.

Both arms CAPOX (oxaliplatin 130mg/m² d1, capecitabine 1000mg/m² d1-14). Experimental adds tislelizumab 200mg d1; control is chemo + RT only.

Both arms short-course 5Gy×5. Experimental is node-sparing (tumor bed only, spares tumor-draining nodes); control is conventional elective-nodal coverage. This target-volume contrast is the RT question.

Primary: pCR (ITT). Secondary: MPR, TRG, organ-preservation rate, EFS, OS, AEs.

Primary pCR and secondary MPR both favored the experimental arm (see figure); EFS, OS, organ-preservation not reported in source.

Experimental arm reported fewer severe GI AEs (author takeaway), plausibly from the smaller node-sparing volume; numeric AE rates not in source.

Control pCR 28.6% matches short-course RT + consolidation chemo benchmarks (RAPIDO ~28%). The novelty is a PD-1 benefit in an MSS population usually IO-refractory, with nodal-RT omission as the immunologic rationale.

Open-label; pCR is a surrogate with EFS/OS immature; the experimental arm confounds node-sparing target volume with added tislelizumab, so the RT-attributable effect can't be isolated; N=154, single country.

Divergent MSS-rectal result from a randomized P3 with blinded-review primary; kept off practice-changing because pCR is a surrogate (EFS/OS immature) and node-sparing is confounded with added tislelizumab.

Randomized phase III, 1:1 (chemoIO+TRT n=115, chemoIO n=113). Stratified by liver and brain metastases. Primary: overall survival; secondary ORR, PFS, toxicity.

Treatment-naïve ES-SCLC, stage IV or stage III ineligible for curative chemoRT, ECOG 0-1, ≥1 measurable thoracic lesion. Asymptomatic or stable brain metastases allowed.

Four cycles durvalumab 1500 mg + carboplatin AUC 5 + etoposide (100 mg/m² IV days 1-3, or 200 mg/m² PO days 2-4) Q3W, then durvalumab 1500 mg Q4W maintenance.

Concurrent thoracic RT 30 Gy in 10 fractions, starting day 21-28. PCI 25-30 Gy offered to responders in both arms; WBRT 20-30 Gy for brain metastases per routine.

Primary OS not met and numerically favored chemoIO alone; PFS and both prespecified subgroups (course completers, no brain/liver metastases) were also null. Effect sizes in figures.

CREST (Slotman, Lancet 2015) used the same 30 Gy/10 fx but as consolidative RT after chemotherapy in responders, before immunotherapy, and suggested a survival benefit. Adding RT concurrently to chemoIO shows none.

Open-label (RT cannot be blinded). Tests only the concurrent schedule, not the consolidative timing prior data supported. No toxicity or RT-delivery data in source to explain the numerically inferior OS.

Randomised phase III, prespecified OS primary, null; contests the CREST-era expectation that thoracic RT benefits ES-SCLC, now tested concurrently with chemoIO.