Abstract
Immunotherapy with anti-PD-1/PDL-1 agents in first-line metastatic non-small cell lung cancer (NSCLC) is chosen based on tumor cell PDL-1 expression. However, the incidence and prognostic value of PDL-1 expression in NSCLC patients with oligometastatic brain disease has never been characterized. We retrospectively analyzed in our SARDO clinical database NSCLC patients with only 1-3 brain metastases (oligometastastic) treated in our University Health Care Center CHUM from 2007-2014. Samples were stained with SP263 (Ventana) antibody against PDL-1. A membranous staining of >25% was considered positive, and scoring was performed by an experienced pathologist. Kaplan-Meier survival curves of all clinical data were performed in SPSS 25. In our cohort of 39 oligometastatic NSCLC patients treated before 2014, none received immunotherapy. A total of 49 specimens (biopsy or surgical) from either the primary or metastatic site were adequate and included in the study. In 10 cases, both primary and metastatic tissue were available for correlation. Overall PDL-1 positivity was 40.8% (20/49), with a positivity of 54.5% (12/22) in primary site samples and 29.6% (8/27) in metastatic brain tissue. Correlation of PDL-1 status between primary and metastatic site in a sub-group of 10 patients was 80% (8/10). Median overall survival (mOS) was significantly shorter for PDL-1 positive patients (8 mos) compared to PDL-1 negative patients (20 mos, p=0.05). 59% (23/39) of patients were aggressively treated for the primary tumor, and 86% (31/39) were aggressively treated for metastatic brain disease. When we controlled for treatment aggressivity of the primary tumor, mOS of PDL-1 positive patients treated aggressively was significantly shorter than mOS of PDL-1 negative patients treated aggressively (15 vs 22 mos, p=0.046). When the primary lung tumor was not addressed aggressively, mOS was the same regardless of the PDL-1 status (4 vs 4 mos). Median progression free survival (mPFS) tended to be longer in PDL-1 positive patients (6.0 vs 9.8 mos, p=0.254). PDL-1 status is concordant between primary and metastatic tissue in 80% of cases. PDL-1 expression is an adverse prognostic factor in NSCLC patients with oligometastatic brain disease, despite treating the patients aggressively for their primary lung cancer and their brain metastasis. In the future, giving early PD1/PDL-1 to oligometastatic PDL-1 positive NSCLC patients could significantly improve their outcome.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
