Postdiagnosis Smoking Cessation and Reduced Risk for Lung Cancer Progression and Mortality
A Prospective Cohort Study
诊断后戒烟可降低肺癌进展和死亡率
一项前瞻性队列研究
Background:
Lung cancer is the leading cause of cancer death worldwide, and about one half of patients with lung cancer are active smokers at diagnosis.
Objective:
To determine whether quitting smoking after diagnosis of lung cancer affects the risk for disease progression and mortality.
Design:
Prospective study of patients with non–small cell lung cancer (NSCLC) who were recruited between 2007 and 2016 and followed annually through 2020.
Setting:
N.N. Blokhin National Medical Research Center of Oncology and City Clinical Oncological Hospital No. 1, Moscow, Russia.
Patients:
517 current smokers who were diagnosed with early-stage (IA-IIIA) NSCLC.
Measurements:
Probabilities of overall survival, progression-free survival, and lung cancer–specific mortality and hazard ratios (HRs) for all-cause and cancer-specific mortality.
Results:
During an average of 7 years of follow-up, 327 (63.2%) deaths, 273 (52.8%) cancer-specific deaths, and 172 (33.7%) cases of tumor progression (local recurrence or metastasis) were recorded. The adjusted median overall survival time was 21.6 months higher among patients who had quit smoking than those who continued smoking (6.6 vs. 4.8 years, respectively; P = 0.001). Higher 5-year overall survival (60.6% vs. 48.6%; P = 0.001) and progression-free survival (54.4% vs. 43.8%; P = 0.004) were observed among patients who quit than those who continued smoking. After adjustments, smoking cessation remained associated with decreased risk for all-cause mortality (HR, 0.67 [95% CI, 0.53 to 0.85]), cancer-specific mortality (HR, 0.75 [CI, 0.58 to 0.98]), and disease progression (HR, 0.70 [CI, 0.56 to 0.89]). （1）Similar effects were observed among mild to moderate and heavy smokers and patients with earlier and later cancer stages.
Limitation:
（2）Exposure measurements were based on self-reported questionnaires.
Conclusion:
Smoking cessation after diagnosis materially improved overall and progression-free survival among current smokers with early-stage lung cancer.
在轻中度、重度吸烟者和早期晚期癌症阶段相同的影响被观察到。
局限性：暴露测量基于自我报道问卷。
（医咖会解读）
Smoker patients with early-stage(I-IIIA) non-small cell lung cancer who were recruited to a large multicentric prospective study of lung cancer survival in Russia were assessed for eligibility to participate in this study(n=722).
Excluded because:
Were followed passively(from death and cancer registries/hospital records)(n=190).
Were followed actively(patients/relatives were contacted),but information on postdiagnosis smoking could not be obtained(n=15).
Smoker patients who were actively followed to collect data on postdiagnosis smoking status were included in this study (n=517).
Continued smoking(n=297),lost to follow-up(n=0),intermittent smoking(n=0).analyzed(n=297),excluded(n=0).
quit smoking(n=220),lost to follow-up(n=0),relapsed smoking (n=8).analyzed (n=220),excluded (n=0).
Table1:baselilne demographinc and clinical characteristics and postenrollment treatments.
Participants,gender,education,median BMI,chronic diseases,regular alcohol drinking,
Median cumulation cigarettes smoked,pack-years.
Histology:squamous cell careinoma;adenocarcinoma;neuroendocrine tumors
Surgery;chemotheraphy;radiation therapy;
Table2：estimates of survival rates among patients with early-stage non-small cell lung cancer who quit smoking versus those who continued smoking after diagnosis.
(1)Adjusted estimates of overall survival
Median survival time.y
Probability of survival at 3 y
Probability of survival at 5 y
(2)Adjusted estimates of progression-free survival
Median progression-free survival,y
Probability of progression-free survival at 3 y
Probability of progression-free survival at 5 y
(3)Adjusted estimates of lung cancer-specific mortality
Median time to lung cancer-specific mortality
Probability of lung cancer-specific mortality at 3 y
Probability of lung cancer-specific mortality at 5 y
Table3:association between quitting smoking postdiagnosis and outcomes patients with early-stage non-small cell lung cancer.
(1).all-cause mortality:adjusted hazard ratio
(2)disease progression(tumor recurrence or death)
(3)adjusted estimates of lung cancer-specific mortality.
Note:estimates are derived feom adjust time-dependent models.
被纳入大型多中心前瞻性（俄罗斯肺癌存活率）研究的早期非小细胞肺癌吸烟患者被评估参与本次研究的资格。
排除原因：
被动随访（来自死亡和癌症登记中心\医院记录）（n=190）.
积极随访（病人/被联系家属），但是诊断后的吸烟情况无法获得。（n=5）.
积极随访收集（在诊断后吸烟情况）数据的吸烟患者被纳入研究中（n=517）.
继续吸烟297人，失访0人，间歇性吸烟0人，分析人群297人，排除0人。
停止吸烟220人，失访0人，反复吸烟8人，分析人群220人，排除0人。
1.什么是无进展生存率？
就是疾病没有任何进一步发展，癌症无进展一般判断：影像学和病人症状。
表1：基线人口学，临床特征，入组后治疗
表2：评估生存率
（1）.调整后总生存率估计
（2）．调整后无进展生存率估计
（3）.调整后因肺癌特异性死亡估计
含义理解：“无进展”表示癌症的前期，没有恶化；“肺癌特异性死亡”，在癌症进展过程中，会因为引起其他并发疾病，或因癌细胞扩展导致死亡等，“癌症特异性死亡”是其中一种死亡方式。而“总生存期”（也称为“全因死亡率“）包含了癌症所有的阶段，所有的死亡方式。
从数据上来看，“癌症特异性死亡”的存活期要比总生存期的存活期要长，表明在癌症发展过程中引起的其他并发症死亡，严重缩短了患者存活时间。
表3：戒烟与患者结局相关性
全因死亡率
疾病过程中（癌症复发或死亡）
肺癌特异性死亡
备注：估计值来自于调整时间相关模型。
积累词汇：
Passively：消极的
Intermittent；间断的
Relapsed；反复的
Chronic：慢性的
Cumulation，累计
cigarettes ，烟草
pack-years：按年打包
Histology:组织学
squamous cell careinoma;鳞状细胞癌
adenocarcinoma;腺癌
neuroendocrine tumors：神经内分泌癌
chemotheraphy;化学治疗
radiation therapy;放射治疗
postenrollment treatment:滚进来治疗，入组后治疗
hazard=risk
recurrence,复发
be derived from,来自于
cessation=stop