247 - Surgical and Pathologic Outcomes After Yttrium-90 Radioembolization Prior to Liver Resection or Transplant

Purpose: This study evaluates surgical, radiologic, and pathologic outcomes of patients undergoing liver resection or transplant following Y-90 radioembolization in contemporary practice.

Materials and Methods: A retrospective review was performed of patients who underwent hepatic resection or transplantation after Y-90 between January 2019 and July 2023 for hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), or metastatic liver disease. Demographics, Y-90 treatment parameters, and operative details were compared with explant pathology, treatment response (mRECIST), recurrence, and survival.

Results: 23 patients (7 women, 16 men; mean age 62 ± 10 years) with HCC (n=15), ICC (n=6), or metastases (n=2) were included. Liver disease etiology included MASH (30%), HCV (22%), EtOH (9%), and HBV (4%). Mean tumor size was 6.5 ± 4.3 cm. Y-90 was delivered as lobar (n=9), segmental (n=2), or lobar with segmental boost (n=12); mean lobar and segmental doses were 195 ± 77 Gy and 195 ± 94 Gy, respectively. No major Y-90–related complications occurred. Mean time to surgery was 145 ± 98 days. R0 resection was achieved in 22/23 (96%) patients. Pathology demonstrated ≥90% necrosis in 13/23 (56%), including 8/23 (35%) with 100% necrosis. Percent necrosis showed a modest inverse correlation with tumor size (p=.09), but not with lung shut fraction (p=.309), liver volume treated (p=.120), or Y-90 dose (p=.997). Treatment response (mRECIST) showed complete or partial response in 43% and 39% of patients, respectively, with no disease progression. No perioperative mortality occurred after transplant (0/9). Following resection, 30-day mortality was 7% (1/14) and 6-month mortality was 28% (4/14). No recurrences or additional deaths occurred over 72 patient-years of follow-up.

Conclusion: Liver resection and transplantation after Y-90 radioembolization performed in patients with large tumors treated with high Y-90 doses resulted in high rates of tumor necrosis, R0 resection, and no disease recurrence. Patients achieved long-term survival after excluding the perioperative period following liver resection. Tumor size demonstrated a potential inverse correlation with the extent of tumor necrosis.