250 - Outcomes of Resin Yttrium-90 Radioembolization with Advanced Dosimetry for Large HCC Tumors (>8cm): A Retrospective Cohort

Tuesday, April 14, 2026

3:36 PM - 3:45 PM ET

Presenting Author(s)

Mohammad Mahdi Khavandi, MD

Postdoctoral research fellow
MD Anderson Cancer Center, United States

Author/Co-author(s)

AA

Anabella Awazi, MD

student
MDAAC, United States
KS

Ketan Shah, MD

Assistant Professor
MD Anderson, United States
Mohamed E. Abdelsalam, MD

Associate Professor
UT MD Anderson Cancer Center, United States
Nariman Nezami, MD

Attending
Georgetown University Medical Center, United States
RA

Rony Avristsher
Bruno Odisio, MD, PhD (he/him/his)

Interventional Radiologist
UT MD Anderson Cancer Center, United States
SL

Sunyoung Lee, MD

researcher
MD Anderson Cancer Center, United States
AK

Ahmed Kaseb, n/a

Physician
The University of Texas MD Anderson Cancer Center, United States
JK

Joshua D. Kuban, MD, FSIR, MA

Associate Professor
MD Anderson Cancer Center, United States
Cheenu Kappadath, PhD

Professor
University of Texas MD Anderson Cancer Center, United States
AM

Armeen Mahvash, MD

Physician
MD Anderson Cancer Center, United States
Peiman Habibollahi, MD, RPVI

Associate Professor
MD Anderson Cancer Center, United States

Purpose: Evaluate the safety, local tumor control, and patient survival after Yttrium-90 (Y-90) resin radioembolization with advanced dosimetry planning for treating large hepatocellular carcinoma (HCC) tumors measuring >8 cm.

Materials and Methods: A Single-center retrospective analysis of HCC patients with index lesions≥8 cm in diameter treated with resin Y-90 (SIR-Spheres) from September 2019 to September 2025 was performed. Treatment Planning was done using the Medical Internal Radiation Dosimetry (MIRD) or Partition Dosimetry for all patients. Administered dose to perfused volume/target tumor dose, lung shunt fraction (LSF), and total absorbed lung dose (Gy) were recorded. Endpoints were overall response rate (ORR) evaluated by mRECIST criteria, local and overall progression-free survival (PFS), and overall survival (OS). Adverse events were graded by CTCAE v6.0.

Results: 24 patients were included in the study. The mean age (±SD) was 69.0 ± 14.4 years, and 17/24 patients (70.8%) were male. Median treated tumor size was 12.5 cm (range, 8.0–17.7), and 11/24 (45.8%) had a solitary lesion. Sixteen patients (66.7%) were treated with MIRD, 6 (25%) with partition dosimetry, and 2 (8.3%) with a combination of both approaches. Treatments were done with DOC, Flex-1, and Flex-3 resin in 5 (20.8%), 14 (58.4%), and 5 (20.8%). In patients treated with the MIRD model, median (range) administered dose and sphere load to the perfused volume were 175 Gy (80–300 Gy) and 44k/cc (24–60k/cc). With partition model, median (range) administered tumor dose and sphere load in the tumor were 150 Gy (100–300 Gy) and 41.5k/cc (20–56k/cc). Median LSF was 3.9% (1.3–16.3%) and median lung dose was 9.8 Gy (1.7–36 Gy). Evaluable ORR at 3, 6, and 9 months was 87% (20/23), 74% (14/19), and 70.4% (10/14), respectively. Local progression occurred in 10/24 (41.7%) and distant progression in 8/24 (33.3%). The median follow-up was 725 days (~23.8 months). Median local PFS and overall PFS were 811 days (~26.6 months) and 685 days (~22.5 months), respectively. Overall survival was 100% at 1 month, and 3 months, 91.7% at 6 months, and 82.9% at 1 year. At the last follow-up, 14/24 (58.3%) were alive. Adverse events included three grade ≥3 events: fatal radiation pneumonitis (n=2; LSF 13% and 20%; lung dose 30 Gy for both) and gastric fistula (n=1), which was managed surgically.

Conclusion: In large ( >8 cm) HCC, resin Y-90 performed by advanced dosimetry results in favorable ORR and OS, with robust early responses. Despite advanced dosimetry, larger tumors with higher LSF pose a challenge in managing lung absorbed dose to avoid radiation pneumonitis.