Abstract 1084
Background
Immune checkpoint inhibitors (ICI) have been demonstrated to improve overall survival (OS) in several cancer types. Atypical patterns of response have been reported including durable responses, pseudoprogression and hyperprogression. We evaluated the occurrence of dissociated response (DR) on immunotherapy.
Methods
We retrieved all patients treated at the Curie Institute with an ICI either alone or in combination with another ICI in the frame of a clinical trial. Patients had to have a baseline CT-scan and at least one follow-up CT-scan, and at least two target lesions (TLs). There was no selection on tumor type. All TLs on CT-scans were assessed by two independent readers according to RECIST 1.1. Three types of DR were evaluated: 1) one TL in partial or complete response (CR/PR) and one progressive TL (DR1), 2) one stable TL and one progressive TL (DR2), and 3) one TL in CR/PR and one stable TL (DR3). Finally, we evaluated the impact of previous radiotherapy and biopsy on TLs on the occurrence of DRs.
Results
1,246 measures of 272 TLs were performed in the 100 patients who met our inclusion criteria. The median number of TLs per patient was 3 [range: 2-5]. 49 out of the 272 TLs (18%) had received prior radiotherapy, and 38 (14%) had been biopsied. Median progression-free survival (PFS) was 3.8 months. Median OS was 13.4 months. Best overall response per patient was a PR/CR in 22%, stable disease (SD) in 33% and progressive disease (PD) in 45%. Best overall response on 272 TLs was a PR/CR in 52 TLs (19%), SD in 142 TLs (52%) and PD in 78 TLs (29%). DR1 were observed in 8% of patients, whereas DR2 and DR3 were observed in 44% and 10% of patients, respectively. While prior irradiation on TLs did not correlate with the occurrence of DRs, DRs were more common when one TL was biopsied ORa = 2.22 (1.28, 3.86) (p = 0.004).
Conclusions
DR with a responding TL and a progressive TL according to RECIST1.1 was observed in 8% of patients. While prior irradiation on TLs did not correlate with the occurrence of DRs, DRs were more common when one TL was biopsied.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
D. Loirat: Advisory / Consultancy, Travel / Accommodation / Expenses: MSD; Advisory / Consultancy: Novartis; Honoraria (institution), Travel / Accommodation / Expenses: Roche; Advisory / Consultancy: AstraZeneca; Advisory / Consultancy, Travel / Accommodation / Expenses: BMS; Advisory / Consultancy: Pfizer. C. Le Tourneau: Advisory / Consultancy: MSD; Advisory / Consultancy: BMS; Advisory / Consultancy: Amgen; Advisory / Consultancy: Merck; Advisory / Consultancy: Serono; Advisory / Consultancy: Roche; Advisory / Consultancy: AstraZeneca; Advisory / Consultancy: Nanobiotix; Advisory / Consultancy: GSK. All other authors have declared no conflicts of interest.
Resources from the same session
2963 - Analytical performance of the Resolution-HRD plasma assay used to identify mCRPC patients with biallelic disruption of DNA repair genes for treatment with niraparib
Presenter: Ira Pekker
Session: Poster Display session 3
Resources:
Abstract
3523 - Results of a global external quality assessment scheme for EGFR testing on liquid biopsy
Presenter: Nicola Normanno
Session: Poster Display session 3
Resources:
Abstract
3295 - Clinical impact of plasma Next-Generation Sequencing (NGS) in advanced Non-small cell lung cancer (aNSCLC)
Presenter: Laura Bonanno
Session: Poster Display session 3
Resources:
Abstract
5632 - Feasibility study of a ctEGFR prototype assay on the fully automated Idylla™ platform
Presenter: Martin Reijans
Session: Poster Display session 3
Resources:
Abstract
3614 - Enhanced Access to EGFR Molecular Testing in NSCLC using a Cell-Free DNA Tube for Liquid Biopsy
Presenter: Theresa May
Session: Poster Display session 3
Resources:
Abstract
5664 - Analysis of circulating tumor DNA in paired plasma and sputum samples of EGFR-mutated NSCLC patients
Presenter: Christina Grech
Session: Poster Display session 3
Resources:
Abstract
4945 - Liquid biopsy and Array Comparative Genomic Hybridization (aCGH)
Presenter: Panagiotis Apostolou
Session: Poster Display session 3
Resources:
Abstract
5746 - Next-generation sequencing panel verification to detect low frequency single nucleotide and copy number variants from mixing cell line studies
Presenter: Rocio Rosas-Alonso
Session: Poster Display session 3
Resources:
Abstract
5901 - Automated rarefaction analysis for precision B and T cell receptor repertoire profiling from peripheral blood and FFPE-preserved tumor
Presenter: Luca Quagliata
Session: Poster Display session 3
Resources:
Abstract
2027 - A Heptamethine cyanine dye is a potential diagnostic marker for Myeloid-Derived Suppressor Cells
Presenter: Chaeyong Jung
Session: Poster Display session 3
Resources:
Abstract