🧠 You can shrink the tumour—but not the tumour bed. New RAPIDO analysis in BJS 2025 shows why small margins after TNT can turn dangerous 👇 💡 Trial: RAPIDO (n = 920, LARC) 🎯 TNT = 5×5 Gy + 6 CAPOX / 9 FOLFOX → TME vs CRT = 25–28×1.8–2 Gy + capecitabine → TME 📊 8-year results: • LRR 10.8% (TNT) vs 5.8% (CRT) → HR 1.91 • Spike seen only after sphincter-preserving surgery (SPS)  → 12.1% (TNT) vs 4.8% (CRT) (HR 2.6) • 🚨 If distal margin ≤ 10 mm → 25.4% (TNT) vs 1.8% (CRT) 💥 (HR 15.5) 🔍 Why? TNT causes tumour shrinkage but leaves scattered viable cells in the original tumour bed. ✂️ Cutting “too close” (<1 cm) may slice through microscopic disease → higher local recurrence. 🇸🇪🇳🇱 Geography tells the story: Sweden = more APR → no difference Netherlands = more SPS & tight margins → higher TNT LRR 🩻 Takeaway: TNT reduces distant mets ✅ but may raise local relapse if DRM ≤ 1 cm ⚠️ ➡️ Surgeons must factor in baseline tumour bed, not just post-TNT shrinkage. 📖 Prata I et al. Br J Surg 2025 🔗 doi.org/10.1093/bjs/znaf190 #OncoTwitter #ColorectalCancer #RectalCancer #RadOnc #Surgery @OncoAlert @esmo_open @BJSurgery @myESMO