81 Addressing disparity and inequity in lung cancer screening (LCS) for women

Introduction Results of LC treatment internationally are dismal; overall 5-year survival is only 7% in women (11% in men). In multiple RCTs, LCS improved survival and reduced LC-specific mortality. There is general agreement that benefit outweighs risk. Research Question Are women underrepresented in research and population LCS? Method Literature review. Analysis Q: Is Lung Cancer (LC) burden lower in women? American Cancer Society estimates 236,740 new LC in 2022; 117,910 men and 118,830 women; 68,820 deaths in men and 61,360 in women. LC incidence is now higher in young women than men. LC deaths in women are projected to rise 43% by 2030 worldwide. Q: Is CT screening safe and effective in women? Survival and mortality reduction were substantially better in women than men in 3 RCTs: NLST, NELSON, LUSI. Q: What is LCS uptake for women in U.S.? Uptake of LCS in eligible women was 3.2% in 2015. Q: Why are fewer women in the U.S. eligible for lung cancer screening (LCS)? 10,044 (16%) annual LC deaths are in women who have never smoked (WNS) (8,125; 11% men). Sensitivities for screening by USPSTF 2021 were 56.8% (women) vs, 71.8%, (men). Women (22.8%) vs. men (14.8%) were excluded by USPSTF 2021 criteria because of smoking exposure below 20 pack-years. Q: is there evidence for safety and efficacy of LCS in North American WNS or those with fewer pack-years? Early NCI-sponsored LCS trials accrued only men. Women are underrepresented in modern trials. NLST 41%, NELSON 16%, VA 3.4%. There is no data on never-smokers or ‘light’ smokers in North America. There is, however, extensive data demonstrating that Asian WNS experience major benefit from early-stage LC diagnosis, curative treatment and survival, comparable to that in male smokers. A systematic review and meta-analysis showed a pooled LCS detection rate of 1.12%. Q: Is there risk of overdiagnosis in WNS? Unknown. WNS have never been screened In North America. Gao et. al. using data from Taiwan, conclude that most Asian WNS, diagnosed by CT screening, are overdiagnosed and will never develop symptoms or die of LC. They advise against screening Asian WNS, despite reporting substantial survival benefit and a small, statistically-significant population mortality reduction in their study. They do not extimate uptake of LCS in Taiwan. Conclusion Unless mitigated by revision of eligibility criteria, gender disparity in LCS will result in a rising preponderance of LC deaths in women in coming years. Gao’s recommendation that population screening in WNS not be implemented until after completion of a RCT, is a recipe for persisting inequity and unnecessary suffering and death. A RCT would require a decade to complete, while women continue to die from LC. As a minimum, it is imperative that North American funding agencies open large prospective observational trials of CT screening that include WNS and women smokers who fail to meet current CMS eligibility criteria. Objectives Examine disparities in lung cancer screening among women and never-smokers. Consider solutions. Method literature evidence review. Results There are major disparities with exclusion of women and never-smokers at risk of lung cancer from both population screening and participation in research trials. Conclusions Funding agencies must conduct prospective trials of lung cancer screening in women and never smokers.