2026P Small Cell Lung Cancer (SCLC) in the KBP-2020-CPHG Cohort and Comparison with 2000 and 2010

The KBP studies are real nationwide prospective multicenter cohort studies of patients (pts) diagnosed with primary lung cancer (PLC), conducted every decade in France since 2000 in non-academic public hospital (NPH) with the same methodology. We describe and compare the characteristics and outcomes of pts with SCLC among the 3 cohorts. 8999 pts were included in 2020, including 1136 pts with SCLC (12.6% [12.1-13.5]). From 2000 to 2010 and 2020, the proportion of SCLC decreased from 16.4% [15.6-17.6] to 13.5% [12.9-14.6] and 12.6% respectively. In 2020 there were 731 men (64.4% [61.5-67.1]) and 405 women (35.7% [32.8-38.5]). The proportion of women among SCLC pts increased from 15.6% [13.3-18.0] to 35.6% in 20 years. The median age at diagnosis also increased from 65.4 [64.5-66.5] years in 2000 to 67.8 [67.3-68.6] years in 2020. In 2020, 24.7% [22.2-27.4] of SCLC were limited-stage. Most of those pts received platinum-etoposide with thoracic radiotherapy. Overall survival (OS) at 1 year was 62.3% [56.7-68.4] and median OS was 19.1 [16.3-21.8] months.75.3% [72.6-77.8] of SCLC were extended. First-line chemotherapy (CT) was a combination of platinum (cisplatin in 7% [5.1-9.5]; carboplatin in 93% [90.5-94.9]) with etoposide for 96.6% [94.6-97.9] of pts. Immunotherapy (IO) was combined with CT in 51% [47.1-54.9] in 2020. In the KBP 2020 cohort, OS for extended SCLC at 1 year was 30.5% [27.5 - 33.9] and median OS was 7.3 [6.5-7.9] months. OS for SCLC at 1 year was stable between the 3 cohorts 38.7% [35.9 - 41.6] in 2020, 35.2% [32.3-38.4] in 2010 and 34.4% [31.5-37.7] in 2000. However, the 2-year survival rate increased from 11.7% [9.7%-14.0] in 2000, 13.6% [11.6-16.0] in 2010 to 19.4% [17.1-22.0] in 2020. The OS of stage IV SCLC unadjusted with performans status according to treatment with IO shows a significant difference in favor of IO with HR=0.54 [0.46 - 0.64] and p<0.0001 with a median survival that increases from 5.5 months [4.4 - 6.7] to 9.9 months [8.9 - 11.3]. The proportion of SCLC among LC is decreasing over time; the proportion of women with SCLC is increasing. While the median OS remains stable at 8.5 months, 2-year OS has improved in 20 years. The benefit of IO is recovered with a profit of more than 4 months.