Top Line: When it comes to definitive radiation for pancreatic cancer, dose escalation may win the battle, while volume expansion wins the war.
The Study: Here is a retrospective look at Miami Cancer Institute’s experience treating 121 consecutive patients with localized pancreatic cancer with definitive MR-guided adaptive ablative radiation, typically the gross tumor receiving 10 Gy x 5 = 50 Gy (BED10 = 100 Gy) and most (93%) with some elective clinical target volume (CTV) margin receiving typically 6.6 Gy x 5 = 33 Gy (BED10 = 54.8 Gy). Of note, hotspots up to ~130–140% were encouraged covering as much GTV as possible which translated to a median CTV dose 46.7 Gy–well above prescription–due to dose-fall-off. Making for an interesting analysis, the CTV design evolved over time from none → vessel-only → extended vascular coverage → full “triangle” space (i.e., between the celiac artery, superior mesenteric artery, common hepatic artery, and portal vein/superior mesenteric vein). The rate of locoregional failure was 14% occurring at a median of 14 months. Of these 17 local failures, 5 were in the primary tumor, 4 in para-aortic lymph nodes, 4 in porta hepatic nodes, 3 at the superior mesenteric artery, and 1 at the celiac artery (n=1; 5.9%).. Strikingly, 0/36 patients treated with full coverage of the “triangle” space experienced locoregional failure. And with all of this, only 4 patients experienced a grade 3 event including nausea, diarrhea and bowel obstruction.
TBL: Anatomically informed elective coverage—especially the “triangle” space—appears to safely and meaningfully move the needle on achieving durable local control with MR-guided adaptive ablative radiation for inoperable pancreatic cancer. | Chuong, Int J Radiat Oncol Biol Phys 2026
The Study: Here is a retrospective look at Miami Cancer Institute’s experience treating 121 consecutive patients with localized pancreatic cancer with definitive MR-guided adaptive ablative radiation, typically the gross tumor receiving 10 Gy x 5 = 50 Gy (BED10 = 100 Gy) and most (93%) with some elective clinical target volume (CTV) margin receiving typically 6.6 Gy x 5 = 33 Gy (BED10 = 54.8 Gy). Of note, hotspots up to ~130–140% were encouraged covering as much GTV as possible which translated to a median CTV dose 46.7 Gy–well above prescription–due to dose-fall-off. Making for an interesting analysis, the CTV design evolved over time from none → vessel-only → extended vascular coverage → full “triangle” space (i.e., between the celiac artery, superior mesenteric artery, common hepatic artery, and portal vein/superior mesenteric vein). The rate of locoregional failure was 14% occurring at a median of 14 months. Of these 17 local failures, 5 were in the primary tumor, 4 in para-aortic lymph nodes, 4 in porta hepatic nodes, 3 at the superior mesenteric artery, and 1 at the celiac artery (n=1; 5.9%).. Strikingly, 0/36 patients treated with full coverage of the “triangle” space experienced locoregional failure. And with all of this, only 4 patients experienced a grade 3 event including nausea, diarrhea and bowel obstruction.
TBL: Anatomically informed elective coverage—especially the “triangle” space—appears to safely and meaningfully move the needle on achieving durable local control with MR-guided adaptive ablative radiation for inoperable pancreatic cancer. | Chuong, Int J Radiat Oncol Biol Phys 2026