Kubík A K, Parkin D M, Zatloukal P
Charles University 3rd Faculty of Medicine, University Hospital Na Bulovce, Department of Pneumology and Thoracic Surgery, Prague, Czech Republic.
Cancer. 2000 Dec 1;89(11 Suppl):2363-8. doi: 10.1002/1097-0142(20001201)89:11+<2363::aid-cncr9>3.3.co;2-n.
The study was launched in the mid-1970s to explore the capability of screening by chest X-ray and sputum cytology to be used as an effective component of the lung cancer control program in the Czech Republic, a Central European country with a high and increasing occurrence of lung cancer in men at that time. A complementary objective of this report is to ascertain whether the cumulative numbers of lung cancer deaths would equalize in the two randomized groups during a prolonged follow-up period.
Six thousand three hundred sixty-four males who were heavy cigarette smokers, aged 40-64 years, were enrolled during a general health survey in 6 districts of the Czech Republic. At initial X-ray and sputum examination, 19 prevalent lung carcinoma cases were diagnosed. After stratified randomization, the remaining subjects entered a 3-year study: the intervention group (3171 participants) was subjected to semiannual chest X-rays and sputum investigation whereas the controls (3174 participants) had 1 examination only by chest X-rays and sputum investigation, 3 years after entry. During a further 3-year follow-up, a chest X-ray was taken at the end of Years 4, 5, and 6 for both the intervention and control groups. Subjects in both groups who were suspected to have lung carcinoma or other disease on the basis of screening results or symptoms were subjected to appropriate diagnostic studies and treatment. Data on all causes of death in Years 1-6 and on deaths from the lung cancer in Years 7-15 of participants in the intervention and control groups were compared.
The incidence rate of lung carcinoma from the intervention group was significantly higher than from the controls in the initial 3-year study period (P < 0.05), but not for the initial 6-year period (P = 0.06). Lung carcinoma cases detected by screening were identified at an earlier stage, were more often resectable, and had a significantly better survival than interval cases diagnosed mainly because of symptoms. There was no significant difference in the lung cancer mortality rate between the 2 groups in the initial 3-year study period or during follow-up prolonged up to Year 15 since enrollment.
The study gave no evidence that screening for lung cancer by chest X-ray is beneficial in terms of reducing mortality. Based on the results of this study, there is no justification to recommend semiannual screening as a component of a comprehensive lung cancer control program.
该研究于20世纪70年代中期启动，旨在探索胸部X光和痰细胞学筛查作为捷克共和国肺癌控制项目有效组成部分的能力。当时，捷克共和国作为一个中欧国家，男性肺癌发病率高且呈上升趋势。本报告的一个补充目标是确定在长期随访期间，两个随机分组中的肺癌死亡累积人数是否会趋于相等。
在捷克共和国6个地区的一次普通健康调查中，招募了6364名年龄在40 - 64岁之间的重度吸烟男性。在初次X光和痰检查时，诊断出19例现患肺癌病例。经过分层随机分组后，其余受试者进入为期3年的研究：干预组（3171名参与者）每半年接受一次胸部X光和痰液检查，而对照组（3174名参与者）在入组3年后仅接受一次胸部X光和痰液检查。在接下来的3年随访期间，干预组和对照组在第4、5和6年末均进行胸部X光检查。两组中根据筛查结果或症状疑似患有肺癌或其他疾病的受试者接受适当的诊断检查和治疗。比较了干预组和对照组参与者在第1至6年所有死因的数据以及第7至15年肺癌死亡的数据。
在最初的3年研究期内，干预组的肺癌发病率显著高于对照组（P < 0.05），但在最初的6年期间并非如此（P = 0.06）。通过筛查发现的肺癌病例在更早阶段被确诊，更常可切除，且与主要因症状诊断出的间隔期病例相比，生存率显著更高。在最初的3年研究期内或自入组起长达15年的随访期间，两组的肺癌死亡率无显著差异。
该研究没有证据表明通过胸部X光筛查肺癌在降低死亡率方面有益。基于本研究结果，没有理由推荐每半年进行一次筛查作为综合肺癌控制项目的一个组成部分。
