Why Women Appear to Have Better Outcomes When Undergoing Screening for Lung Cancer

Area of Science:

• Pulmonology
• Oncology
• Radiology

Background:

• Randomized controlled trials (RCTs) show lung cancer screening (LCS) with computed tomography (CT) reduces mortality compared to chest radiography (CXR).
• Women appear to benefit more from LCS than men, but the reasons are unclear.

Purpose of the Study:

• To investigate the reasons behind the observed sex-based differences in LCS outcomes.
• To analyze the impact of sex on lung cancer mortality reduction from CT screening.

Main Methods:

• Secondary analysis of the National Lung Screening Trial (NLST) data.
• Used descriptive statistics and a competing risk proportional hazards model.
• Examined differences in screening outcomes by sex, including an interaction between sex and screening arm.

Main Results:

• Lung cancer (LC) mortality was lower in women (1.7%) than men (2.1%) overall.
• CT screening showed a significant LC mortality reduction in women (sHR=0.74) but not men (sHR=0.91).
• Comorbid conditions like COPD and heart disease, more prevalent in men, were associated with increased LC death.

Conclusions:

• Women demonstrated a greater, though not statistically significant, reduction in LC mortality with CT screening.
• Higher prevalence of comorbid diseases in men may explain their increased all-cause and LC mortality.
• These findings suggest sex-specific factors influence LCS effectiveness.