Background and objective: Fourty years ago, Tokuhata and Lilienfeld provided the first epidemiologic evidence of familial aggregation of lung cancer. Familial aggregation and increased familial risk for lung cancer have been reported in several studies, subsequently. But the results are not consistent with each other. The aim of this study is to further explore the relationship between family history of lung cancer and lung cancer risk.
Methods: By searching PubMed, CENTRAL, CBM, CNKI and VIP, we collected both domestic and overseas published documents before November, 2009 on family history of lung cancer and lung cancer risk. RevMan version 4.2 was used to perform meta-analysis on the case-control study results, the combined odds ratio (OR) and the 95% confidence interval (CI) were calculated as well.
Results: Twenty-eight publications were included into the combined analysis, which indicated that the lung cancer risk of the probands' first-degree relatives was 1.88 times higher than that of their controls' (P < 0.001). In the sub-study, compared with the controls' father mother and siblings, the OR of the probands' father mother and siblings was 1.62 (P < 0.001), 1.96 (P < 0.001) and 1.92 (P < 0.001), respectively. For smoking status, lung cancer risk in first-degree relatives of smoking probands was 1.73 (P < 0.001) times higher than that of their corresponding controls'. And for non-smoking subjects the lung cancer risk was 1.42 (P = 0.02) times higher in proboands' first-degree relatives. For gender categories, lung cancer risk in first-degree relatives of female probands was 1.89 (P < 0.001) times higher than that of their corresponding controls'. And for male subjects, the lung cancer risk was 1.99 (P < 0.001) times higher in proboands' first-degree relatives.
Conclusion: Lung cancer risk was increased in probands' first-degree relatives, and obvious familial aggregation of lung cancer was observed in this study.
背景与目的: 四十多年前Tokuhata和Lilienfeld首次从流行病学的角度证实肺癌的家族聚集现象。随后的多个研究也证实了家族聚集现象是肺癌危险性的一个家族性成分，但研究结果并不完全一致。本研究旨在进一步分析和评价一级亲属患肺癌者在肺癌发生中的作用。
方法: 检索PubMed、CENTRAL、中国生物医学文献数据库系统（CBM）、中国期刊全文数据库（CNKI）、中文科技期刊全文数据库（VIP）等收集国内外公开发表的肺癌家族聚集性的病例对照研究。采用RevMan version 4.2统计软件对各研究结果进行分析，计算其合并优势比和95%可信区间。
结果: 纳入合并分析的文献共有28篇，分析结果表明：肺癌先证家系一级亲属患肺癌的风险是对照家系一级亲属的1.88倍（P < 0.001)。分层分析，先证家系的父亲、母亲及兄弟姐妹患肺癌的风险分别是对照家系的1.62倍（P < 0.001）、1.96倍（P < 0.001）和1.92倍（P < 0.001）；吸烟和非吸烟先证者一级亲属患肺癌的风险分别是对照组中吸烟者和非吸烟者一级亲属患肺癌的1.73倍（P < 0.001）和1.42倍（P=0.02）；女性和男性肺癌先证者一级亲属患肺癌的风险性分别是对照组中女性和男性一级亲属患肺癌的1.89倍（P < 0.001）和1.99倍（P < 0.001）。
结论: 先证家系一级亲属患肺癌的风险性增加，肺癌存在明显的家族聚集现象。