192P - KRAS as predictive biomarker of response to checkpoint inhibitors in NSCLC
- Alfredo Addeo (CH)
- Javier Torralvo (CH)
- Pierre-Yves Dietrich (CH)
- Alfredo Addeo (CH)
Abstract
Background
AntiPD1/antiPDL1-based immunotherapy has changed dramatically the prognosis of non small cell lung cancer (NSCLC)pwith a substantial improvement of overall survival (OS) and even presenting long lasting responses in a subset of patients (pts). Several factors have been associated with the likelihood of better survival, which include the smoking exposure and the presence of KRAS-mutation according to data from randomized clinical trials that compared chemotherapy to these immunotherapeutic (IO) agents.
Methods
We have collected all the cases of stage IV NSCLC pts treated with IO agents within our institution form January 2016 to december 2017 with particular interest to pts harbouring KRAS –mutation. We have assessed their clinical outcomes: disease control rate (DCR) Partial response (PR), progression free survival (PFS) and overall survival (OS).
Results
45 patients with advanced NSCLC were treated with anti PD1 or anti PDL1 (Nivolumab 71%, Pembrolizumab 22% and Atezolizumab 7%, respectively) from January 2016 to December 2018 within our Institution. Twenty (44%) pts were identified as Adenocarcinoma with KRAS-mutation. The subgroup included 39% of female, median age of 61 years, and all patients had PS0-1. The immunotherapy (IO) was administered as 1st, 2nd and ≥ 3rd therapy in 7%, 82% et 11% of the 45 pts, respectively: DCR was 74% with 49% PR and in 40% of pts the response lasted ≥12 months. Within the KRAS mutation group (20 pts) the DCR was 83.5% and the PR was 67%. Within this cohort the PFS was 9.5 months and OS was 42 months. At the time of analysis 7/45 pts were still receiving the immunotherapy treatment.
Conclusions
Our retrospective analysis has showed that KRAS-mutation pts represent a subgroup of pts that seem to substantially benefit from IO agents in terms of both response rate, PFS and OS. This is in line with the literature and despite the limitations of a retrospective analysis, it confirms the possible strong correlation among KRAS mutation and response to IO. Further prospective studies are warranted to better define the role of KRAS mutation in this context.
Legal entity responsible for the study
HUG
Funding
Has not received any funding
Disclosure
All authors have declared no conflicts of interest.
