Abstract 5562
Background
Selective internal radiation therapy (SIRT) using yttrium-90 resin microspheres was compared to sorafenib 400mg bid in a phase 3 randomised trial (SARAH) in the treatment of intermediate or advanced hepatocellular carcinoma (HCC) not amenable to curative treatment. The trial did not show a survival benefit of SIRT over sorafenib in the intention to treat (ITT) population. The effectiveness of SIRT may depend on the tumour-absorbed dose, which can be predicted with the analysis of SPECT/CT imaging during each patient work-up, before the administration of SIRT. In this post hoc analysis we explored the comparative effectiveness of SIRT and sorafenib in a subgroup of patients defined by their predicted tumour-absorbed dose.
Methods
Cox proportional hazards regressions were conducted in the ITT population of the SARAH trial. Since predicted tumour-absorbed dose was only available for SIRT, the comparisons between SIRT at a given dose and sorafenib were not randomised. Inverse probability of treatment weighting (IPTW) using propensity scores was used to account for potential confounding by differences in prognostic factors between the treatment arms, with the sorafenib sample reweighted to match the SIRT patients. A cut-off value of 100 Gy was used for tumour absorbed dose, approximating the median dose, with 120 Gy used in a sensitivity analysis.
Results
For patients with a predicted dose ≥100 Gy, the hazard ratio (HR) for overall survival (OS) from the unweighted sample was 0.70 (95% CI: 0.50-0.98, p = 0.04). After reweighting, the HR was 0.74 (95% CI: 0.51-1.04, p = 0.09). Predicted mean OS was 22.5 months (mos) for SIRT vs 17.9 mos for sorafenib. Results were similar with a 120 Gy cut-off: the HR for OS was 0.76 (95% CI 0.52-1.10, p = 0.14). Among patients who received subsequent curative therapy post-SIRT, 11/12 were alive at the end of follow-up (median 26.6 mos, range 16.0-34.8) and only one had a predicted dose <100 Gy.
Conclusions
The analysis suggests that HCC patients may derive a meaningful benefit from treatment using SIRT with a predicted dose ≥100 Gy compared to sorafenib. This may inform personalised treatment selection and clinical trial design.
Clinical trial identification
NCT01482442.
Editorial acknowledgement
Legal entity responsible for the study
Sirtex Medical UK Ltd.
Funding
Sirtex Medical UK Ltd.
Disclosure
N.S. Hawkins: Honoraria (institution), Advisory / Consultancy, Research grant / Funding (institution): Sirtex. P.J. Ross: Honoraria (self), Travel / Accommodation / Expenses: Amgen; Honoraria (self), Advisory / Consultancy, Travel / Accommodation / Expenses: Bristol-Myers Squibb; Advisory / Consultancy: Celgene; Travel / Accommodation / Expenses: Bayer; Honoraria (self), Advisory / Consultancy: Pierre Fabre; Honoraria (self): Roche; Honoraria (self), Travel / Accommodation / Expenses: Servier; Research grant / Funding (institution): Sanofi; Honoraria (self), Advisory / Consultancy: Shire; Honoraria (self), Advisory / Consultancy, Travel / Accommodation / Expenses: Sirtex. D.H. Palmer: Advisory / Consultancy, Travel / Accommodation / Expenses: Bayer; Advisory / Consultancy, Travel / Accommodation / Expenses: Eisai; Advisory / Consultancy, Travel / Accommodation / Expenses: Bristol-Myers Squibb; Advisory / Consultancy, Travel / Accommodation / Expenses: MSD; Advisory / Consultancy, Travel / Accommodation / Expenses: AstraZeneca. V. Vilgrain: Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: Sirtex. All other authors have declared no conflicts of interest.
Resources from the same session
3911 - Defining a SUV decrease cut-off in PET/CT response monitoring after one cycle of preoperative breast cancer chemotherapy
Presenter: Marcin Kubeczko
Session: Poster Display session 2
Resources:
Abstract
1849 - Effect of thioredoxin 1 quantity detection to complement the mammography in breast cancer diagnosis
Presenter: Younju Lee
Session: Poster Display session 2
Resources:
Abstract
2221 - Identification of ultralow risk breast cancer patients (probable overdiagnosis)
Presenter: Salvador Gamez Casado
Session: Poster Display session 2
Resources:
Abstract
5291 - Prevalence of Vitamin D3 deficiency among women with early breast cancer receiving chemotherapy in an oncology dayward.
Presenter: Warner Finstad
Session: Poster Display session 2
Resources:
Abstract
4247 - Changes in ER pathway activity score during neoadjuvant letrozole to assess therapy response and predict disease free survival (DFS) in ER positive breast cancer patients
Presenter: Arran Turnbull
Session: Poster Display session 2
Resources:
Abstract
568 - Second primary malignancies in patients with breast cancer.
Presenter: Carlos Erasun Lecuona
Session: Poster Display session 2
Resources:
Abstract
1428 - Phase II randomized trial of neoadjuvant trastuzumab and pertuzumab (TP) with either palbociclib + letrozole (Pal+L) or paclitaxel (Pac) for elderly patients with estrogen receptor & HER2 positive (ER+/HER2+) Breast Cancer (BC) (International Breast Cancer Study Group IBCSG 55-17, TOUCH)
Presenter: Laura Biganzoli
Session: Poster Display session 2
Resources:
Abstract
1479 - Neoadjuvant HER2-targeted therapy with or without immunotherapy with pembrolizumab (neoHIP): an open label randomized phase 2 trial
Presenter: Heather McArthur
Session: Poster Display session 2
Resources:
Abstract
1481 - A randomized phase 2 study of peri-operative ipilimumab, nivolumab and cryoablation versus standard care in women with residual, early stage/resectable, triple negative breast cancer after standard-of-care neoadjuvant chemotherapy
Presenter: Heather McArthur
Session: Poster Display session 2
Resources:
Abstract
4334 - ALEXANDRA/IMpassion030: A phase 3 study of standard adjuvant chemotherapy with or without atezolizumab in early stage triple negative breast cancer.
Presenter: Michail Ignatiadis
Session: Poster Display session 2
Resources:
Abstract