Abstract 5544
Background
Several studies have suggested that combining radiotherapy (RT) to immunotherapy (IO) may be synergistic but many questions are still pending regarding the radiation modalities to optimize this combination, such as the choice of the lesion to irradiate. Radiomics consists in the analysis of quantitative data extracted from standard medical imaging to generate imaging biomarkers. A previous study published in The Lancet Oncology has shown that a radiomic signature could predict the CD8 cells infiltration, which is associated with the activity of anti-PD-1/PD-L1. We aimed to assess whether this biomarker could help to guide IO-RT combinations.
Methods
Patients from three clinical studies of IO-RT combinations with advanced solid tumors in two institutions were screened. Patients with available baseline (E0) and first evaluation (E1) CTs were included. Immunotherapy consisted in 4 different drugs. Hypofractionated conformal RT or stereotactic RT of one tumor lesion was delivered after the start of IO for most of the patients. The irradiated lesion and a sample of non-irradiated lesions were delineated from E0 and E1 CTs. Radiomics features were extracted and the published radiomic signature was applied to estimate the CD8 cells.
Results
84 patients were included. 244 tumor lesions were delineated on the E0 CT, including the 84 lesions which were selected for irradiation. Median time between IO and RT start was 21 days (IQR: 9-24), and 2.4 mo between E0 and E1 (IQR: 1.3 - 3). 80 irradiated lesions and 152 non irradiated lesions remained at E1. At baseline, the volume and the radiomic score of TIL (RS) were not different between the two groups (irradiation or no) (p = 0.94 and 0.50). While the mean volume of the analyzed lesions was not different from E1 to E0 (p = 0.15), irradiated lesions were significantly smaller at E1 (p = 0.03). A high RS in the irradiated lesion at E1 (compared to the median value) was associated with PFS (HR = 0.57, IC95%: 0.345-0.95, p = 0.031) irrespective of the volume in multivariate analysis but was not significantly associated with OS.
Conclusions
Radiomic score of the irradiated lesion was associated with PFS. Such biomarker may help to guide the selection of the lesion to irradiate in IO-RT combinations.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Gustave Roussy Cancer Campus.
Funding
Fondation pour la Recherche Médicale, SIRIC-SOCRATE 2.0, Fondation ARC, Amazon.
Disclosure
R. Sun: Travel / Accommodation / Expenses: AstraZeneca. N.L. Sundahl: Travel / Accommodation / Expenses: Merck Sharpe & Dohme; Travel / Accommodation / Expenses: Astellas; Travel / Accommodation / Expenses: Bayer; Travel / Accommodation / Expenses: Bristol-Myers Squibb. P. Ost: Research grant / Funding (institution): Merck Sharpe & Dohme; Research grant / Funding (institution): Astellas; Research grant / Funding (institution): Janssen; Travel / Accommodation / Expenses: Ipsen; Honoraria (self), Travel / Accommodation / Expenses: Ferring Pharmaceuticals; Honoraria (self): Bayer. C. Massard: Advisory / Consultancy: Amgen; Advisory / Consultancy: AstraZeneca; Advisory / Consultancy: Bayer; Advisory / Consultancy: Celgene; Advisory / Consultancy: Genentech; Advisory / Consultancy: Ipsen; Advisory / Consultancy: Jansen; Advisory / Consultancy: Lilly; Advisory / Consultancy: Novartis; Advisory / Consultancy: Pfizer; Advisory / Consultancy: Roche; Advisory / Consultancy: Sanofi; Advisory / Consultancy: Orion. E. Deutsch: Advisory / Consultancy, Research grant / Funding (institution): Roche Genentech; Advisory / Consultancy, Research grant / Funding (institution): Merck Serono; Research grant / Funding (institution): AstraZeneca; Research grant / Funding (institution): BMS; Research grant / Funding (institution): MSD. All other authors have declared no conflicts of interest.
Resources from the same session
2507 - KEYLYNK-010: Phase 3 Study of Pembrolizumab (pembro) Plus Olaparib (OLA) vs Enzalutamide (ENZA) or Abiraterone (ABI) in ENZA- or ABI-Pretreated Patients (pts) With Metastatic Castration-Resistant Prostate Cancer (mCRPC) Who Had Progression on Chemotherapy (CTx)
Presenter: Evan Yu
Session: Poster Display session 3
Resources:
Abstract
2944 - PROSTRATEGY: A Spanish Genitourinary Oncology Group (SOGUG) multi-arm multistage (MAMS) phase III trial of immunotherapy strategies in high-volume metastasic hormone-sensitive prostate cancer.
Presenter: Jose Arranz Arija
Session: Poster Display session 3
Resources:
Abstract
3535 - A phase 1 study of AMG 160, a half-life extended bispecific T cell engager (HLE BiTE) immuno-oncology therapy targeting PSMA, in patients (pts) with metastatic castration-resistant prostate cancer (mCRPC)
Presenter: Ben Tran
Session: Poster Display session 3
Resources:
Abstract
4951 - ProBio: An outcome-adaptive, multi-arm, open-label, multiple assignment randomised controlled biomarker-driven trial in patients with metastatic castration-resistant prostate cancer (EudraCT: 2018-002350-78, NCT03903835)
Presenter: Johan Lindberg
Session: Poster Display session 3
Resources:
Abstract
2892 - A phase 3 randomized, placebo-controlled, double-blind study of niraparib plus abiraterone acetate and prednisone versus abiraterone acetate and prednisone in patients with metastatic prostate cancer (NCT03748641)
Presenter: Kim Chi
Session: Poster Display session 3
Resources:
Abstract
2427 - The Extended/Phase II Study of Safety And Tolerability Of Proxalutamide (GT0918) In Subjects With Metastatic Castrate Resistant Prostate Cancer (mCRPC) Who Failed Either Abiraterone (Abi) Or Enzalutamide (Enza)
Presenter: Nicholas Vogelzang
Session: Poster Display session 3
Resources:
Abstract
3224 - Addition of an oral docetaxel treatment (ModraDoc006/r) to androgen deprivation therapy (ADT) and intensity-modulated radiation therapy (IMRT) in patients with high risk N+M0 prostate cancer
Presenter: Marit Vermunt
Session: Poster Display session 3
Resources:
Abstract
3312 - A phase II randomized, open-label study comparing salvage radiotherapy in combination with 6 months of androgen-deprivation therapy with LHRH agonist or antagonist versus anti-androgen therapy with apalutamide in patients with biochemical progression after radical prostatectomy.
Presenter: Piet Dirix
Session: Poster Display session 3
Resources:
Abstract
2829 - Health-Related Quality of Life (HRQoL) and Updated Follow-Up From KEYNOTE-057: Phase 2 Study of Pembrolizumab (pembro) for Patients (pts) With High-Risk (HR) Non–Muscle Invasive Bladder Cancer (NMIBC) Unresponsive to Bacillus Calmette-Guérin (BCG)
Presenter: Ronald de Wit
Session: Poster Display session 3
Resources:
Abstract
2673 - Clinical activity of vofatamab (V), an FGFR3 selective antibody in combination with pembrolizumab (P) in metastatic urothelial carcinoma (mUC), updated interim analysis of FIERCE-22
Presenter: Arlene Siefker-Radtke
Session: Poster Display session 3
Resources:
Abstract