Understanding East-West differences in subsolid nodules: prevalence and overdiagnosis implications in lung cancer screening

Owing to the widespread opportunistic LDCT screening leading to increased overdiagnosis in Asian countries, such as South Korea, mainland China, and Taiwan, this study seeks to analyze the divergence in SSN prevalence between Eastern and Western nations, focusing on the influence of SSN on the growing overdiagnosis trend, notably among females. This retrospective study collected data from 4166 participants who underwent baseline LDCT in a hospital-based cohort between January 2014 and August 2021. Clinical parameters, including age, sex, lung imaging reporting and data system (Lung-RADS) categories, smoking history, pack-year dose, and SSN characteristics, were extracted from electronic medical records. Additionally, a narrative review and pooled analysis integrated relevant published studies on the prevalence of subsolid nodules and sex disparities. The study encompassed 4166 participants, with females accounting for 49.3% and males for 50.7%, with a mean age of 53.38 ± 10.89. The prevalence of SSNs was significantly higher in females (20.1%) than in males (12.6%). Pooled analysis across seven studies revealed a significantly higher prevalence of SSN in Eastern countries (12.6%) compared to the prevalence in Western countries (3.6%) (test for subgroup differences: <i>p</i> &lt; 0.01; I² = 100%). Additionally, a notable sex difference was observed in the prevalence of SSNs (risk ratio = 0.489, 95% CI: 0.301–0.796, <i>p</i> &lt; 0.01; reference group: male group). Apart from differences in clinical management and health literacy regarding SSNs between Eastern and Western countries, the high prevalence of SSNs in Asian nations, particularly among females, significantly contributes to the issue of overdiagnosis in opportunistic lung cancer screening in Asian countries. Tailored sex-specific strategies and risk prediction models are essential for effective screening optimization.鉴于韩国、中国大陆及中国台湾等亚洲国家广泛开展机会性低剂量计算机断层扫描（LDCT, Low-Dose Computed Tomography）筛查导致过度诊断率攀升，本研究旨在分析东西方国家亚实性肺结节（SSN, Subsolid Pulmonary Nodule）患病率的差异，重点探讨SSN对日益加剧的过度诊断趋势的影响，尤其关注女性群体。本回顾性研究收集了2014年1月至2021年8月期间，某医院队列中4166名接受基线LDCT检查参与者的相关数据。研究人员从电子病历中提取了多项临床参数，包括年龄、性别、肺影像报告和数据系统（Lung-RADS）分类、吸烟史、包年吸烟量以及SSN特征。此外，本研究通过叙事性综述及荟萃分析，整合了已发表的关于亚实性肺结节患病率与性别差异的相关研究。本研究共纳入4166名参与者，其中女性占比49.3%，男性占比50.7%，平均年龄为53.38±10.89岁。女性的SSN患病率达20.1%，显著高于男性的12.6%。对7项研究开展的荟萃分析结果显示，东方国家的SSN患病率为12.6%，显著高于西方国家的3.6%（亚组差异检验：*p* < 0.01；*I*² = 100%）。此外，研究还观察到SSN患病率存在显著性别差异（风险比=0.489，95%置信区间：0.301~0.796，*p* < 0.01；参照组为男性组）。除东西方国家在SSN临床管理与健康素养层面存在差异外，亚洲国家较高的SSN患病率（尤其在女性群体中），是导致亚洲国家机会性肺癌筛查中过度诊断问题加剧的重要因素。制定针对性的性别特异性筛查策略与风险预测模型，对于高效优化肺癌筛查工作至关重要。