1367P - Sex disparities in patient and tumour characteristics, and overall survival in advanced non-small cell lung cancer (NSCLC) within the precision oncology era: A Danish nationwide observational study

Background

Cancers often exhibit sexual dimorphism. Yet, the impact of sex on patient and tumour characteristics as well as survival remains largely unexplored in advanced NSCLC following the introduction of immune checkpoint inhibitors and targeted therapies into routine clinical practice.

Methods

In this cohort study, we identified adults diagnosed with advanced NSCLC from January 1, 2017, to December 31, 2023, using Danish nationwide health registries and clinical databases. We compared females to males across demographic, social, socioeconomic, patient and tumour characteristics (including PDL-1 expression and driver mutations), treatments, and overall survival (OS) from diagnosis and from initiation of first line of treatment (LOT1). Cox proportional hazards regression modeling was employed, adjusting for key covariates in both the overall cohort and stratified by stage, histological subtype, PD-L1 expression level, and treatment type. Propensity score matching was conducted as a sensitivity analysis.

Results

Among 14,639 individuals, sex distribution was even, with males comprising 50% (n=7,325). Median OS from diagnosis was 8·8 months (95% confidence interval [CI] 8·4-9·2) for females and 7·0 months (95% CI: 6·7-7·3) for males, while from initiation of LOT1, median OS was 14·2 months (95% CI: 13·5-15·2) for females and 10·8 months (95% CI: 10·3-11·5) for males. Patient and tumour characteristics differed between sexes, however after adjustment the female-to-male mortality hazard ratio was 0·84 (95% CI: 0·81-0·88) from diagnosis and 0·80 (95% CI: 0·75-0·84) from initiation LOT1. Sex-differential mortality was also identified in stratification on most covariates.

Conclusions

This study significantly enhances our understanding of sex-based disparities in advanced NSCLC. The findings indicate a potential underlying biological sex difference with clinical and pharmacological implications, favoring longer survival in females. Our results underscore the critical role of acknowledging sex as a key variable in oncology trials, research and clinical practice.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.