Procedural Path to 91% Complete Pathologic Necrosis

This episode breaks down COBRAS, a 2026 Radiology multicenter study of 303 patients and 364 treatment-naive HCC tumors bridged to liver transplant with glass microsphere radiation segmentectomy. Listen to the end to hear an expert commentary by Dr. Sid Padia from UCLA Interventional Radiology. Four Parameters: Microsphere activity of at least 1,087 Bq, at least 8,000 microspheres per mL, a single-compartment dose of at least 400 Gy, and an angiosome-to-tumor ratio of 16 or greater. Stacked Result: Positive predictive value for complete pathologic necrosis rose from 74% with activity alone to 91% with all four thresholds met. Meeting none carried a 78% failure rate. Biggest Lever: ATR had the highest odds ratio in the model at 3.4, which argues for pulling the catheter proximal to cover occult parasitic feeders rather than superselecting to the tumor border. Caveats: Retrospective, glass microspheres only, limited to patients who reached transplant, and CPN remains a surrogate endpoint not yet tied to long-term survival. Tune in to learn why the physics inside the vial and the position of your catheter may matter as much as the dose number on the screen. This podcast is generated using an AI model that has been trained in the context of endovascular surgery and interventional radiology in addition context of the article cited below. The content was reviewed and edited by multiple healthcare professionals in the field. Berman ZT, De la Garza-Ramos C, Montazeri SA, et al. Consortium on Bridging Radiation Segmentectomy (COBRAS): A Multicenter Study of Complete Pathologic Necrosis in Hepatocellular Carcinoma. Radiology. 2026;319(2):e251923.