Although lung cancer is the leading cause of cancer death in women in the US, the 2021 United States Preventive Services Task Force (USPSTF) lung cancer screening guidelines, released in March, result in more women being ineligible for lung cancer screening than men, according to a recent study in Chest. Study researchers found that adding the validated PLCOm2012 risk prediction model criteria to the USPSTF guidelines may reduce this gender disparity in lung cancer screening.
Both the 2013 and the most recent 2021 USPSTF eligibility criteria rely on an age-pack-years-quit-years category approach to identify people at high risk for lung cancer. In contrast, the validated PLCOm2012 risk prediction model does not feature an age-pack-years-quit-years restriction; instead, it includes a total of 11 risk predictors: age, race/ethnicity, family history of lung cancer, personal history of other cancers, diagnosis of chronic obstructive pulmonary disease (COPD) or emphysema, body mass index (BMI), highest education level attained, current or former smoking status, smoking intensity (average number of cigarettes per day), duration of smoking (years), and years since cessation.
In the recent study, a team of researchers from the US and Canada retrospectively assessed the sensitivity of USPSTF vs PLCOm2012 eligibility criteria in 883 patients with lung cancer from the Chicago Race Eligibility for Screening Cohort (CREST). The investigators stratified their analyses by gender. The study relied on the PLCOm2012 model at-risk thresholds of ≥1.7%/6 years and >1.0%/6 years for comparisons between the USPSTF 2013 and USPSTF 2021 eligibility criteria, respectively.
Sensitivities for screening according to the USPSTF 2013 were 46.7% (95% CI, 41.6-51.8) for women and 56.8% (95% CI, 52.3-61.2) for men (P =.003). According to the USPSTF 2021, the sensitivities for screening were 64.6% (95% CI, 59.6-69.4) for women and 71.8% (95% CI, 67.6-75.7) for men (P =.02).
The sensitivities for screening according to the PLCOm2012 ≥1.7%/6 years criteria were 64.6% (95% CI, 59.6-69.4) and 70.4% (95% CI, 66.1-74.4) for women and men, respectively (P =.07). In comparison, the sensitivities for PLCOm2012 ≥1.0%/6 years were 77.4% (95% CI, 73.0-81.5) for women and 82.4% (95% CI, 78.7-85.6) for men (P =.07).
Women were significantly more likely than men to be considered ineligible for screening by the USPSTF 2021 criteria, as the former group’s smoking exposure was <20 pack-years (22.8% vs 14.8%; odds ratio, 1.70; 95% CI, 1.19-2.44; P =.002). Approximately 27% of ineligible women were considered eligible according to the PLCOm2012 >1.0%/6 years criteria.
According to the researchers, limitations of this study included its retrospective nature, single-center design, and the lack of education status for a “sizeable proportion” of the population studied.
The investigators concluded that women at risk for lung cancer should be offered “commensurate access to screening as men,” and that “USPSTF and similar (Centers for Medicare and Medicaid Services) guidelines” must “reflect this equity in screening” because insurance coverage decisions in the US are based on these guideline recommendations.
Likewise, the investigators added that the addition “of the PLCOm2012 risk model to USPSTF eligibility criteria” may further “reduce gender disparities in lung cancer screening and could improve lung cancer outcomes” across the board.
Pasquinelli MM, Tammemägi MC, Kovitz KL, et al. Addressing gender disparities in lung cancer screening eligibility: USPSTF versus PLCOm2012 criteria. Chest. Published online July 9, 2021. doi:10.1016/j.chest.2021.06.066