Virtual Library
Start Your Search
Gerardo Huidobro
Author of
-
+
FP12 - Tumor Biology and Systems Biology - Basic and Translational Science (ID 188)
- Event: WCLC 2020
- Type: Posters (Featured)
- Track: Tumor Biology and Systems Biology - Basic and Translational Science
- Presentations: 1
- Moderators:
- Coordinates: 1/28/2021, 00:00 - 00:00, ePoster Hall
-
+
FP12.09 - Molecular Insight into NADIM Clinical Trial: Potential Immune Biomarkers of Pathological Response for NSCLC Patients. (ID 3552)
00:00 - 00:00 | Author(s): Gerardo Huidobro
- Abstract
- Presentation
Introduction
Many studies have demonstrated that chemo-immunotherapy is a promising approach for NSCLC patients but still exists a lack of prediction biomarkers of survival. We have recently showed that pathological response is a surrogate of progression free survival (PFS) including infiltrating immune cells as potential biomarker of pathological response in NADIM clinical trial (Provencio et al., 2020. Lancet Oncology, in press).
New biomarkers in peripheral blood are being described, focused on the immune system response. Preliminary data was presented at WCLC 2019 however additional results are included in this report. Here we describe the effect of chemo-immune neoadjuvant treatment on resectable NSCLC stage III patients’ immune system and describe blood biomarkers that could help to identify responders to this combination therapy.
Methods
Peripheral mononuclear cells (PBMCs) and plasma from NADIM clinical trial patients before and after chemo-immune neoadjuvant treatment were used. Phenotyping and activation levels of immune cell populations were analyzed by flow cytometry, focused on CD4 T cells, CD8 T cells, T cells NK like and NK cells. Moreover, characterization of the immune response was evaluated by a cytokine array.
Clinical evaluation of pathological response, classified patients in 3 groups, complete (CPR, 0% tumor cells), major (MPR, <10% viable tumor) and incomplete (IPR, >10% viable tumor). Wilcoxon and Kruskall-Wallis statistic tests were used.
Results
Even though we have previously described a decrease of T lymphocytes on tissue after treatment, we do not see these changes on blood. Thus, percentages of PBMCs (T cells, B cells, NK cells and macrophages) did not vary after neoadjuvant treatment. However, lower levels of activated CD4 T cells and NK cells were observed. Interestingly, this decrease was exclusively statistically significant for patients who achieved a CPR, but no differences were observed for MPR or IPR. As expected, detection of PD1+ cells after neoadjuvant Nivolumab (anti-PD1) treatment was almost completely abrogated, however, a trend for higher PD1+ cell proportions was observed in patients achieving CPR at diagnosis.
Furthermore, many cytokines involved in immune response and described as putative biomarkers for immunotherapy in NSCLC as IL-2, IL-15, IL-6, IL-13 or IFN-gamma, among others, were decreased after neoadjuvant treatment. Notably, stratifying by pathological responses, this decrease was statistically significant only for non-complete responses.
Conclusion
The analysis of immune cell markers on blood samples could be a source for potential surrogate markers of pathological response to neoadjuvant treatment on NSCLC patients.
Similarly, to what occurs in tissue, CPRs showed differences compared to MPR or IPR in some blood markers, both at the cellular and cytokine level. Thus, after treatment, patients achieving CPRs do not seem to reduce their levels of cytokines such as IL-2, IL-15, IL-6, IL-13 or IFN-g associated with anti-tumor response, but they do reduce their levels of activated CD4 and NK cells
Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
-
+
P60 - Tumor Biology and Systems Biology - Basic and Translational Science - Immune Bio (ID 198)
- Event: WCLC 2020
- Type: Posters
- Track: Tumor Biology and Systems Biology - Basic and Translational Science
- Presentations: 1
- Moderators:
- Coordinates: 1/28/2021, 00:00 - 00:00, ePoster Hall
-
+
P60.07 - TMB and Selected Mutations in Resectable Stage IIIA NSCLC Patients Receiving Neo-Adjuvant Chemo-Immunotherapy from NADIM Trial (ID 2142)
00:00 - 00:00 | Author(s): Gerardo Huidobro
- Abstract
Introduction
Tumor Mutational Burden (TMB) assessment and identification of specific mutations associated to anti-PD1 blockade therapy resistance have become a novel approach to predict the clinical benefit to anti-PD1/PDL1 therapy. However, the clinical relevance of these parameters in terms of pathological response and PFS in neo-adjuvant chemo-immunotherapy has not been established. To answer this question we analysed samples from the NADIM study (NCT03081689), in which resectable stage IIIA NSCLC patients were treated with neoadjuvant chemo-immunotherapy with Nivolumab.
Methods
Pretreatment TMB, defined as the number of nonsynonymous variants (missense and nonsense single nucleotide variants (SNVs)), plus insertion and deletion variants (INDELs) detected per megabase (Mb) of exonic sequence, was estimated from 27 patients that had enough diagnostic material for next generation sequencing using the Oncomine Tumor mutation Load assay (ThermoFisher) following manufacturer’s instructions. The panel covers 1.7 Mb of 409 genes with known cancer associations. Regarding pathological responses, patients were classified into 3 groups: pathologic complete response (pCR) (0% viable tumour at any localization tested), major pathologic response (MPR, <10% viable tumour) and pathologic incomplete response (pIR) (>10% of viable tumour). At data analysis, median follow-up time was 22.7 months.
Results
Median TMB was 5.89 (range 1.68 – 73.95). No differences in TMB value between histologies (adenocarcinoma vs squamous cell), smoking status (former vs current), age or sex were observed. Somatic mutations were identified in lung cancer driver genes such as TP53, KRAS, EGFR, CDKN2A, NOTCH1, BRAF and in specific genes associated with resistance to immunotherapy such as STK11, KEAP1, and RB1. No genomic alterations in ALK, ROS1, PTEN or ERBB2 were found.
Based on literature, a poor prognosis mutation signature (presence of EGFR, STK11, KEAP1 or RB1 mutations) was generated. A third of the sequenced patients (9/27) harboured at least one mutation in one of these genes.
Pathological response data was available from 23 out of 27 patients sequenced. Both the TMB value and the presence of these resistance mutations were not associated with the degree of pathological response.
Regarding PFS, TMB alone was not predictive of disease progression using different thresholds. However, the presence of these resistance mutations was associated with shorter PFS (log-rank p-value=0.032). The median PFS for mutated patients was 21.4 months (95% CI 16-26 months) while median PFS was not reached in non-mutated patients.
Additionally, the combination of this mutational signature with TMB (absence of resistance mutations and TMB-Higher than median) was able to distinguish patients that strongly benefit from this therapy. Although the median PFS was not reached in both groups yet, statistically significant differences were observed (log-rank p-value=0.046). PFS at 18 and 24 months was 100% (95% CI not estimable) for Non-mutated patients with TMB-High vs 70% (95% CI 50-89%) and 58% (95% CI 35-81%) for the rest of patients (mutated patients plus Non-mutated patients with TMB-Low).
Conclusion
TMB did not predict benefit from chemo-immunotherapy induction in our cohort. However, the presence of EGFR/STK11/KEAP1/RB1 mutations alone, or in combination with TMB, may help identify patients that unlikely benefit from neo-adjuvant chemo-immunotherapy
