Center for Thoracic Surgery, University of Insubria, Ospedale di Circolo, Varese, Italy.
Lung Cancer. 2013 Apr;80(1):50-4. doi: 10.1016/j.lungcan.2012.12.014. Epub 2013 Jan 5.
The effectiveness of screening for lung cancer (LC) in smokers on a population level, as distinct from the special circumstances that may apply in a randomized trial of selected volunteers, has not been thoroughly investigated. Here we evaluate by the standardized mortality ratio (SMR) indicator the impact of a chest X-ray (CXR) screening programme carried out at community level on LC mortality in smokers.
All smokers of >10 pack-years, of both genders, ages 45-75 years, resident in 50 communities of the Province of Varese, Italy, screening-eligible, in 1997 were invited by their National Health Service (NHS) general practitioner physicians to a nonrandomized programme of five annual CXR screenings. The entire invitation-to-screen cohort (n=5815 subjects) received NHS usual care, with the addition of CXR exams in volunteer participants (21% of invitees), and was observed through December 2006. To overcome participants' selection bias of LC mortality assessment, for the entire invitation-to-screen cohort we estimated the LC-specific SMR, based on the local reference population receiving the NHS usual care.
Over the 8-year period 1999-2006, a total of 172 cumulative LC deaths were observed in the invitation-to-screen cohort; 210 were expected based on the reference population. Each year in the invited cohort the observed LC deaths were fewer than expected. The cumulative LC SMR was 0.82 (95% CI, 0.67-0.99; p=0.048), suggesting that LC mortality was reduced by 18% with CXR screening.
Implementation of a CXR screening programme at community level was associated with a significant reduction of LC mortality in smokers.
在人群层面上，对肺癌（LC）进行筛查的效果与在特定志愿者的随机试验中可能适用的特殊情况不同，尚未得到彻底研究。在这里，我们通过标准化死亡率（SMR）指标评估在社区层面进行胸部 X 射线（CXR）筛查计划对吸烟者 LC 死亡率的影响。
1997 年，意大利瓦雷泽省 50 个社区的所有 >10 包年的吸烟者，无论性别，年龄在 45-75 岁之间，筛查合格，都被他们的国家卫生服务（NHS）全科医生邀请参加非随机的五年一次的 CXR 筛查计划。整个邀请筛查队列（n=5815 名受试者）接受 NHS 的常规护理，并在志愿者参与者中增加 CXR 检查（邀请者的 21%），并观察到 2006 年 12 月。为了克服 LC 死亡率评估的参与者选择偏倚，我们对整个邀请筛查队列进行了基于接受 NHS 常规护理的当地参考人群的 LC 特异性 SMR 的估计。
在 1999 年至 2006 年的 8 年期间，邀请筛查队列共观察到 172 例累积的 LC 死亡；基于参考人群，预计有 210 例。在邀请队列中的每一年，观察到的 LC 死亡人数都少于预期。累积的 LC SMR 为 0.82（95%CI，0.67-0.99；p=0.048），表明 CXR 筛查使 LC 死亡率降低了 18%。
在社区层面实施 CXR 筛查计划与吸烟者 LC 死亡率的显著降低相关。
