Reich Jerome M, Kim Jong S, Asaph James W
Thoracic Oncology Program, Earle A. Chiles Research Institute, Portland, OR.
Fariborz Maseeh Department of Mathematics and Statistics, Portland State University, Portland, OR.
Clin Lung Cancer. 2015 Sep;16(5):391-7. doi: 10.1016/j.cllc.2015.03.003. Epub 2015 Mar 27.
The aim of this study was to estimate the effect of lobectomy on life expectancy in healthy smokers and consider the implications for lung cancer screening.
In a retrospective cohort study that provided a minimum of 15 years of follow-up, we analyzed lung cancer survival, all-cause survival, and fatality (1-survival) of 261 persons with stage I non-small-cell lung cancer who underwent lobectomy at Portland Providence Medical Center between 1978 and 1994. We: (1) compared 5-year disease-free fatality (non-lung-cancer fatality) with lung cancer fatality; and (2) based on actuarial data that demonstrated life expectancy equivalence of the healthiest smokers (whom we assumed would be comparable with subjects judged eligible for lobectomy) in the US population, we compared their long-term, disease-free survival (our primary end point) with actuarial expectations by computing the Kaplan-Meier survival function of the differences between lifetimes since surgery in disease-free persons versus matched, expected remaining lifetimes in the US population.
(1) Five-year disease-free fatality (16.1%) was 58% as high as 5-year lung cancer fatality (27.6%); (2) disease-free survival was reduced by 6.9-years (95% confidence interval, 5.5-8.3), 41% of actuarial life expectancy (17 years). The divergence from expected survival took place largely after 6 years of follow-up.
Lobectomy materially diminishes long-term disease-free survival in the healthiest smokers--persons judged healthy enough to tolerate major surgery and to have sufficient pulmonary reserve to sustain loss of one-fifth of their lung tissue. In screened populations, diminished survival in overdiagnosed persons will offset, to an undetermined extent, the mortality benefit imparted by preemption of advanced lung cancer.
本研究旨在评估肺叶切除术对健康吸烟者预期寿命的影响，并探讨其对肺癌筛查的意义。
在一项提供至少15年随访的回顾性队列研究中，我们分析了1978年至1994年间在波特兰普罗维登斯医疗中心接受肺叶切除术的261例I期非小细胞肺癌患者的肺癌生存率、全因生存率和死亡率（1-生存率）。我们：（1）比较了5年无病死亡率（非肺癌死亡率）和肺癌死亡率；（2）根据精算数据显示美国人群中最健康的吸烟者（我们假设其与被判定适合肺叶切除术的受试者具有可比性）的预期寿命相等，通过计算无病患者术后生存时间与美国人群中匹配的预期剩余寿命之间差异的Kaplan-Meier生存函数，将他们的长期无病生存率（我们的主要终点）与精算预期进行比较。
（1）5年无病死亡率（16.1%）是5年肺癌死亡率（27.6%）的58%；（2）无病生存率降低了6.9年（95%置信区间，5.5-8.3），占精算预期寿命（17年）的41%。与预期生存的差异主要发生在随访6年后。
肺叶切除术在很大程度上降低了最健康吸烟者的长期无病生存率——这些人被判定健康到足以耐受大手术，并且有足够的肺储备来维持五分之一肺组织的损失。在筛查人群中，过度诊断人群生存率的降低将在一定程度上抵消早期肺癌筛查所带来的死亡率益处，但抵消程度尚不确定。
