Interventional Oncology

Session: Wednesday Closing Plenary Session: Act Local, Think Global: IR and its role in Immuno-oncology

Updated analysis of DOSISPHERE-01 trial: a long term analysis of overall survival.

Wednesday, March 8, 2023

10:40 AM – 10:50 AM

Location: Phoenix Convention Center, Hall 6 (Plenary)

Featured Presenter(s)

EG

Etienne Garin, MD, PhD

Nuclear Medicine Physician
Université De Rennes 1/CRLCC Eugène Marquis

Disclosure information not submitted.

Author/Co-author(s)

LT

Lambros Tselikas, MD, PhD

Attending
Gustave Roussy
BG

Boris Guiu, MD, PhD

Chair, Radiology
St-Eloi University Hospital – Montpellier School of Medicine
JC

Julia Chalaye, MD, PhD

not attending
Henry Mondor Hospital
BC

Boris Campillo-Gimenez, MD

Methodologist
cancer Institute Eugène Marquis

Disclosure(s):

Etienne Garin, MD, PhD: Boston Scientific: Advisory Committee/Board Member (), Consultant ()

Purpose: DOSISPHER-01 study (1) demonstrated at interim analysis a strong improvement of response and overall survival (OS) using ⁹⁰Y loaded glass microsphere with personalized dosimetry compared to standard dosimetry in non-operable locally advanced hepatocellular carcinoma patients. The aim of this report is to provide long term analysis of OS.

Materials and Methods: In this phase II study, treatment arm was randomly assigned (1:1) to personalized dosimetry arm (PDA) with the goal to deliver at least 205Gy (if possible more than 250-300 Gy) to the index lesion or to the standard dosimetry arm (SDA), with the goal to deliver 120±20Gy to the treated volume. Response rate was the primary endpoint and OS was one the secondary endpoints. This report is a post hoc long term analysis of OS.

Results: 60 HCC patients, with a least one lesion >7cm and at least > 30% of hepatic reserve, were randomized (ITT population, PDA 31, SDA 29), and 56 treated (modified ITT population, 28 in each arm). Portal vein thrombosis (PVT) was present in 68% and of the patients (ITT and modified ITT population). The median follow-up for long term analysis was 65.8 months (2.1-73.1). Median OS was 22.9 months in the PDA versus 10.8 months in the SDA, HR 0.52 (95% CI: 0.3-0.91), p=0.023 in the ITT population, and respectively 24.8 months versus 10.7 months, HR 0.51 (95%CI:0.29-0.9), p=0.02 in the modified ITT population. According to dosimetry results, median OS was 22.9 months for patients with a Tumor Absorbed Dose (TAD) ≥ 205 Gy versus 10.3 months for those with a TAD < 205 Gy, HR 0.42 (95% CI:0.22-0.81), p=0.0095 and median OS was 22.9 months for patients with a Perfused Liver Dose (PLD) ≥ 150 Gy versus 10.3 months for those with a TAD < 205 Gy, HR 0.42 (95% CI: 0.23-0.75), p=0.0033.Finally, median OS was not reached in the patients secondarily resected (n=11, 10 in the PDA and 1 in the SDA) versus 10.8 months for the patients without secondary resection (n=45), HR 0.17 (95%CI:0.065-0.43), p=0.0002. OS rates at 1, 2, 3, and 5 years are presented in table.

Conclusion:

after longer follow-up, personalized dosimetry maintained a meaningful improvement of OS. OS was dramatically improved for patients accurately down staged towards resection.