Abstract 349P
Background
Immune checkpoint inhibitors (ICIs) have changed the prognosis of Non-Small Cell Lung Cancer (NSCLC). However, there is a lack of biomarkers to appropriately select the most adequate combination, and to predict whether patients may respond to ICIs.We aimed to evaluate whether circulating immune cell populations are predictors of response to first-line treatment of advanced NSCLC with ICIs combined or not with chemotherapy.
Methods
A multi-institutional prospective study for NSCLC patients receiving ICIs as monotherapy (n=86) or combined with chemotherapy (n=76). Flow cytometry was used for circulating cell immunophenotyping. A multivariable statistical analysis was employed to select those circulating cell populations associated with progression-free survival (PFS) and overall survival (OS) as the main clinical outcomes. Bayesian modeling was used to develop prediction models for both treatments.
Results
Monocytes were found to be associated with PFS and OS for patients receiving anti-PD-(L)1 monotherapy (C-Index values of 0.64 and 0.65 respectively) and NK and CD4+ T cell populations for those receiving ICIs combined with chemotherapy (C-Index values of 0.74 and 0.75 respectively). Pretreatment use of corticosteroids (>10 mg prednisone equivalent) has proven to have a significant impact in circulating cell populations, thus we decided to also include it in the modelling. Based on these variables, different prediction models were built and assembled into an ICI response score (ICIRS), which calculates PFS and OS probabilities at a given time point. To ease ICIRS’s clinical implementation, nomograms and a web-based calculator (https://remote.iislafe.san.gva.es/sample-apps/icirs_score/) were developed.
Conclusions
Our study shows that circulating levels of classical monocytes, CD4+ T, NK cells and pretreatment corticosteroids use are suitable variables to build an ICIRS to estimate disease progression and survival in a personalized manner for NSCLC patients receiving ICIs with/without chemotherapy. This strategy, based on accessible variables, is easily implemented in clinics. The ICIRS might also be helpful in making decisions whether chemotherapy use is advisable or not.
Legal entity responsible for the study
The authors.
Funding
Instituto Carlos III de Madrid; Ministerio de Ciencia, Innovación, y Universidades.
Disclosure
All authors have declared no conflicts of interest.