Sex disparities in lung cancer: Results of the KBP-2020-CPHG study

The KBP-CPHG observational studies, conducted every 10 years, have shown a significant increase in the proportion of women with lung cancer, rising from 16.0 % in 2000 to 34.6 % in 2020 (P < 0.0001). We report differences in clinical, tumor, and prognostic characteristics between women and men.

All patients with primary lung cancer diagnosed in 2020 across 81 French centers were included. Patient and tumor characteristics were compared by sex. Patients in the KBP-2020 cohort were also compared with those from the 2000 and 2010 cohorts.

The KBP-2020 study included 3,095 women and 5,846 men. Smoking was more frequent in men (93.6 %) than in women (75.7 %). Women were diagnosed at a younger age (median 66.8 vs 68.6 years; P < 0.0001) and had slightly better performance status (0-1: 76.2 % vs 73.7 %; P < 0.001). Adenocarcinoma predominated in both sexes but was more frequent in women (65.5 % vs 51.0 %; P < 0.0001). Molecular testing was performed more often in women (64.5 % vs 52.3 %; P < 0.0001) and identified more genetic alterations (58.2 % vs 42.1 %; P < 0.0001). Among stage IV adenocarcinoma cases, EGFR mutations were more frequent in women (27.5 % vs 7.9 %; P < 0.001). Women had better overall survival than men (4-year OS: 34.7 % vs 23.7 %; median OS: 21.9 vs 12.6 months; P < 0.0001). Female sex was associated with improved survival in multivariable analysis (HR 0.79; 95 % CI 0.74-0.84; P < 0.0001). This association was no longer significant in a stage IV NSCLC-restricted model including an interaction with first-line treatment (HR 0.88; 95 % CI 0.77-1.02; P = 0.087).

Women with lung cancer had better survival than men, but this advantage was no longer significant after adjustment for treatment differences.