# ABO‐Blood Group Associates With Survival Outcomes in Patients With Metastatic Non‐Small Cell Lung Cancer Treated With Pembrolizumab Monotherapy

## TL;DR

This study finds that ABO blood group O is linked to better survival in lung cancer patients treated with pembrolizumab alone, but not when combined with chemotherapy.

## Contribution

The study identifies ABO blood group O as a novel biomarker for improved survival in pembrolizumab monotherapy for lung cancer.

## Key findings

- ABO blood group O was associated with better overall and progression-free survival in pembrolizumab monotherapy.
- No significant ABO blood group effect was observed in patients receiving chemoimmunotherapy or chemotherapy alone.
- Younger age and BGO were independent predictors of favorable outcomes in the monotherapy cohort.

## Abstract

In patients with metastatic non‐small cell lung cancer (NSCLC) with high programmed death‐ligand 1 (PD‐L1) expression, there is still a lack of biomarkers to identify patients with maximum benefit from first‐line treatment with checkpoint inhibitor therapy (CIT) alone. This work examines the impact of different ABO blood groups (BG) on the response to CIT monotherapy.

Retrospective analysis of patients with stage IV NSCLC and high PD‐L1 expression (tumor proportional score/TPS ≥ 50%), receiving first‐line therapy with pembrolizumab alone or in combination with chemotherapy at the West German Cancer Center from 2017 to 2022. Study endpoints were overall survival (OS) and progression‐free survival (PFS).

Eighty‐two patients were included in the analysis. Twenty‐two patients (27%) received first‐line therapy with pembrolizumab alone (monoimmunotherapy cohort/MIC), of which seven patients (32%) had BGO. Sixty patients (73%) were treated with pembrolizumab combined with platinum‐based chemotherapy (chemoimmunotherapy cohort/CIC), of which 38 (63%) had BGO. In MIC, younger age and BGO were independent predictors of favorable OS (BGO vs. other ABO‐BG: HR 0.22, 95% CI: 0.1–0.9; p = 0.037; median OS 62 versus 19 months) and PFS (BGO vs. other ABO‐BG: HR 0.21, 95% CI: 0.1–0.8; p = 0.024; median PFS 39 vs. 4 months). There was no significant impact of ABO‐BG in patients treated with CIC. In support, a historical control group treated with chemotherapy alone also showed no prognostic impact of the ABO‐BG.

BGO associates with favorable survival in patients with NSCLC receiving pembrolizumab monotherapy, but not in patients with chemo‐immunotherapy or chemotherapy. Further validation of this promising strategy for personalized decision‐making is warranted.