肺癌低剂量螺旋CT筛查的研究进展

<正>肺癌是当前对人类威胁最大的恶性肿瘤。在全球范围内,其死亡率高居男性的首位,女性的第二位[1]。在我国及美国,其死亡率已稳居男、女性恶性肿瘤死亡率的首位[2,3]。美国2010年肺癌预期死亡病例占癌症总死亡人数的28%,超过前列腺癌、     

低剂量螺旋CT肺癌筛查及肺结节的研究现状

肺癌已经成为对人类生命威胁最大的恶性肿瘤之一,其发病和死亡均居恶性肿瘤首位,因此对肺癌的筛查显得尤为重要。随着低剂量螺旋CT的广泛应用,肺结节的检出率在不断增加,对其研究也在不断深入。本文就肺癌筛查的现况、肺结节良恶性影响因素做一阐述,以期为肺癌和肺结节的防治提供依据。     

低剂量螺旋CT肺癌筛查研究进展

肺癌已经成为全球范围内癌症死亡的首位死因,其5年生存率很低。肺癌的筛查和早期诊断是改善肺癌生存,降低肺癌死亡率的关键。低剂量螺旋CT是近20年肺癌筛查的热点,随机对照试验研究已经证实其可降低肺癌死亡率。但目前低剂量螺旋CT筛查仍存在一些问题。本文对近年来低剂量螺旋CT能否降低肺癌死亡率的争议、随机对照试验的结果及存在的问题进行综述,并对未来低剂量螺旋CT在肺癌筛查中的应用做一展望。     

肺癌低剂量螺旋CT筛查应用现状及问题探讨

摘 要：肺癌是全球最常见的癌症死亡原因。早期肺癌检出率低是导致肺癌高死亡率的一大原因。肺癌低剂量螺旋CT（low-dose computed tomography,LDCT）筛查是目前全球公认的能够有效降低肺癌死亡率的方法。尽管LDCT已被证实在肺癌筛查中的作用,但其临床运用仍有许多问题亟需解决。全文对筛查人群的选择、肺结节管理流程的完善、肺癌预测因子的开发方面作一综述。     

基于社区的早期肺癌低剂量螺旋CT扫描筛查上海实践初探

背景与目的：作为中国最常见的恶性肿瘤,肺癌的发病率及死亡率长期保持在较高水平。而有效改善肺癌预后,关键在于早期诊断和规范治疗。本研究密切结合上海社区医疗服务发展现状,整合各级医疗机构优势资源,探索基于上海社区的早期肺癌低剂量螺旋CT筛查路径模式。方法：2013年8月—2014年8月,针对上海市闵行区部分试点社区,以低剂量螺旋CT作为肺癌初步筛查手段,在高危人群中开展肺癌早期诊断,并结合以微创手术治疗为主的多学科综合治疗模式,构建涵盖肺癌预防、诊断、治疗、康复及随访等医疗服务措施的综合治疗立体网络。结果：筛查总人数为11332人(男性7144人,女性4188人)。其中,明确诊断恶性肿瘤29例,包括原发性肺癌27例、转移性肺癌1例和乳腺癌1例;筛查原发性肺癌发病率为238.26×10-5;0~Ⅰ期肺癌共22例,在原发性肺癌中占81.48%。结论：基于上海社区的早期肺癌低剂量螺旋CT筛查路径模式提高肺癌早期诊断率,具有可行性及有效性,可在有条件的社区及医疗卫生机构推广。     

低剂量螺旋CT肺癌筛查检出肺结节的处理及进展

低剂量螺旋CT(LDCT)肺癌筛查可以显著提高肺癌患者的生存率,降低患者的死亡率.目前全球已开展多个著名的肺癌筛查研究项目,国内外多个组织及机构也有相关肺癌筛查指南或指导意见发布,本文主要对CT筛查检出的肺结节处理及进展予以综述.     

低剂量螺旋CT对高危人群的肺癌筛查结果分析

摘 要：［目的］ 了解低剂量螺旋CT对高危对象进行肺癌筛查的特点。［方法］ 对上海市闵行区36 924名肺癌高危人群于2014~2016年间进行低剂量螺旋CT肺癌筛查,根据筛查结果,分别按性别、年龄段进行分组,比较肺癌检出率、病理分型及临床分期。［结果］ 低剂量螺旋CT筛查共检出肺癌患者273例,总检出率为0.74%,其中男性143例,女性130例;腺癌、鳞癌、小细胞癌及未分型分别为166例、4例、9例及94例,0~1期、2~3期及4期和未分期分别为118例、22例、13例及120例。肺癌总检出率、腺癌构成比、腺癌检出率女性均高于男性。男性肺癌检出率随年龄增长呈上升趋势,女性肺癌检出率随年龄增长呈上升趋势,到70~79岁年龄段出现小幅下降,后又呈上升趋势。［结论］ 采用低剂量螺旋CT对高危人群进行肺癌筛查有助于肺癌的早期发现并提高肺癌检出率,应在该人群中积极开展。     

低剂量CT筛查肺癌之现状和展望

肺癌高居全球癌症死亡的首位.遗憾的是,因出现症状而就诊的肺癌多属晚期,预后甚差.肺癌筛查的想法可追溯到上世纪五十年代,摄胸片筛查了6000名男性志愿者,虽生存期较有症状组稍有延长,但死亡率无明显差异.随着低剂量CT检查技术的开展,于上世纪九十年代中、晚期报道,用低剂量CT筛查有较高的早期肺癌检出率.使肺癌筛查重又燃起希望.但因这些筛查试验缺乏对照组,故不足以确定低剂量CT筛查是否能降低肺癌死亡率.文献中对仍有很多争论.为确定CT筛查是否真正有益,美国全国肺癌筛查试验及NELSON试验进行之中.预计2010年可得出最终结果.肺癌筛查是一复杂的有争议的问题,通过CT筛查是否能实质性地降低肺癌死亡率,仍不清楚.尽管CT筛查充满希望,但仍存在一些问题有待解决,在采取大面积筛查前须对其有所了解.     

低剂量螺旋CT对7496名社区肺癌高危人群的筛查研究

摘 要：［目的］ 探讨低剂量螺旋CT（LDCT）对社区肺癌高危人群的筛查效果。 ［方法］ 在社区招募7496名肺癌高危人群进行LDCT筛查。肺癌高危人群定义为年龄40岁以上,并且具有下列任何一项者：20包年以上的吸烟史、肺癌家族史、肺部既往病史（慢性阻塞性肺病、肺结核）、职业接触史（石棉、氡、砷、铬、镍接触史）。以发现至少一个≥4 mm非钙化结节为LDCT筛查的阳性结果。［结果］ 7496名肺癌高危人群进行LDCT肺癌筛查,非钙化结节≥4 mm 者共1057名（14.1%）。年龄≥55岁的高危人群结节阳性率显著高于年龄<55岁者（14.9% vs 9.7%;χ2=22.27,P<0.001）。筛查出肺癌33例,占结节阳性者的3.1%,肺癌检出率为0.44%。共确诊21例非小细胞肺癌,其中0~Ⅰ期11例,早期诊断率为52.4%。［结论］ LDCT肺癌筛查有助于提高肺癌的早期诊断率和非钙化结节的检出率,尤以55岁以上人群值得推广。     

乌鲁木齐市社区肺癌高危人群低剂量螺旋CT筛查结果分析

[目的]对乌鲁木齐市城市社区40～69岁人群开展肺癌筛查,评价筛查效果.[方法]对问卷评估的11 512名肺癌高危人群低剂量螺旋CT检查.[结果]共完成肺癌CT筛查3436人,依从性为20.4％.共发现1294人有肺内结节(37.6％),367人有阳性结节(10.7％),可疑肺癌16例(0.46％).男性阳性结节的检出率高于女性.60～69岁年龄组在阳性结节、小结节、可疑肺癌的检出率都高于其他年龄组.[结论]低剂量螺旋CT适合肺癌的高危人群筛查,有助于早期发现肺内的阳性结节和相关疾病,60岁以上人群肺癌的筛查应该引起高度重视.     

湖南省2017—2018年肺癌低剂量螺旋CT筛查结果和依从性分析

目的 分析湖南省2017—2018年度城市癌症早诊早治项目中肺癌低剂量螺旋CT(Low-dose spiral CT,LDCT)筛查初步结果和依从性影响因素,为开展肺癌防控工作提供依据.方法 在长沙市五个城区,动员所有40～74岁常住居民填写高危风险评估问卷,评估的肺癌高危者接受肺癌LDCT临床筛查,分析肺癌高危评估和...     

CT screening for lung cancer: update 2007

Screening is the pursuit of the early diagnosis of cancer before symptoms occur. The purpose of early diagnosis is to provide early treatment, which potentially prevents death from the cancer. The usefulness of screening depends on how early the cancer can be diagnosed and how many deaths can be prevented by early treatment as compared with later symptom-prompted diagnosis and treatment. The goal of the Early Lung Cancer Action Project investigators was to develop an efficient methodology that would provide an ever-accumulating, continually updated body of evidence for evaluation of emerging new technologies for screening for cancer. This methodology recognizes that screening is a sequential process that starts with the pursuit of the early diagnosis of cancer followed by early treatment. It also recognizes that diagnostic research is fundamentally different from treatment research. To fully understand the current discussions on the evidence for lung cancer screening, key definitions are provided, including the differentiation between the first, baseline round of screening and all subsequent rounds of repeat screening and baseline and repeat cancers and their distribution by cell type. These definitions are critical in analyzing the results of various screening reports as they are not used by all. To provide optimal screening, a regimen for the diagnostic workup must be specified starting with the definition of the initial test, its positive result, and the workup for a positive result leading to a diagnosis of cancer. Assessment of diagnostic performance does not require a control group, but does require confirmation of the diagnosis. For assessment of the effectiveness of early treatment, a comparison group is needed. The comparison group may be formed by randomly assigning people with screen-diagnosed lung cancer to immediate or delayed treatment, as has been done for prostate cancer. This provides a direct assessment of any potential overdiagnosis of the cancer resulting from screening. Alternatively, a quasiexperimental control group can be used consisting of participants diagnosed with the cancer who have refused or delayed their treatment even though they are candidates for it.     

Efficacy of CT screening for lung cancer in never-smokers: analysis of Japanese cases detected using a low-dose CT screen

CT-screening for lung cancer is fairly widely used for both smokers and never-smokers in East Asia because the mortality rate for never-smokers due to this cancer is relatively high in this region. We performed comparative analyses, as a retrospective study, on three lung cancer arms detected by CT-screen, X-ray-screen, and via analysis of clinicopathological features and outcomes in never-smokers from a symptomatic-prompted group of patients. The total study cohort comprised 218 patients in CT group, 160 in X-ray group, and 82 in symptomatic-prompted group. The percentage of bronchioloalveolar carcinoma (BAC) was 65.1% in CT-screen group. The ratio of stage IA tumors in CT-screen group was 88.5% and the ratio of advanced cases (i.e. stages IIIB + IV) was 2.3%. The 5-year-survival rates were 95.0% in CT-screen, 73.0% in X-ray-screen and 40.0% in symptomatic-prompted group. We performed further sub-analysis which excluded pure BACs (i.e. Noguchi types A and B) or pure GGOs within a 10 mm diameter because this is indicative of a very favorable prognosis. Based on this sub-analysis the number of the subjects in each group became 76 in CT group; 140 in X-ray group and 77 in symptomatic-prompted group. The principal characteristics of the patients such as age and sex became almost even in the three arms. In CT-screen subgroup, the ratio of stage IA cancer was 69.7% and of advanced cases was 6.6%. This advanced ratio was lower than both X-ray-screen (22.1%) and symptomatic-prompted (61.9%) groups. The 5-year-survival rates were 89.9% among CT-screen group patients, 72.6% for X-ray screen cases and 39.1% in symptomatic-prompted group. A CT-screen was found to be one of the independent prognostic factors for lung cancer (HR, 0.28; 95% CI, 0.12-0.72) and based on this would be expected to reduce the risk of lung cancer death by 78% compared with non-screened cases. In conclusion, CT will improve the survival rate and decrease the rate of advanced cancers in never-smokers via the existing annual screening system. CT-screening is also an independent prognostic improvement factor in never-smokers, and will therefore reduce the risk of lung cancer death.     

Mortality outcomes of low-dose computed tomography screening for lung cancer in urban China: a decision analysis and implications for practice

Background:Mortality outcomes in trials of low-dose computed tomography (CT) screening for lung cancer are inconsistent.This study aimed to evaluate whether CT screening in urban areas of China could reduce lung cancer mortality and to investigate the factors that associate with the screening effect.Methods:A decision tree model with three scenarios (low-dose CT screening,chest X-ray screening,and no screening) was developed to compare screening results in a simulated Chinese urban cohort (100,000 smokers aged 45-80 years).Data of participant characteristics were obtained from national registries and epidemiological surveys for estimating lung cancer prevalence.The selection of other tree variables such as sensitivities and specificities of low-dose CT and chest X-ray screening were based on literature research.Differences in lung cancer mortality (primary outcome),false diagnoses,and deaths due to false diagnosis were calculated.Sensitivity analyses were performed to identify the factors that associate with the screening results and to ascertain worst and optimal screening effects considering possible ranges of the variables.Results:Among the 100,000 subjects,there were 448,541,and 591 lung cancer deaths in the low-dose CT,chest X-ray,and no screening scenarios,respectively (17.2％ reduction in low-dose CT screening over chest X-ray screening and 24.2％ over no screening).The costs of the two screening scenarios were 9387 and 2497 false diagnoses and 7 and 2 deaths due to false diagnosis among the 100,000 persons,respectively.The factors that most influenced death reduction with low-dose CT screening over no screening were lung cancer prevalence in the screened cohort,low dose CT sensitivity,and proportion of early-stage cancers among low-dose CT detected lung cancers.Considering all possibilities,reduction in deaths (relative numbers) with low-dose CT screening in the worst and optimal cases were 16 (5.4％) and 288 (40.2％) over no screening,respectively.Conclusions:In terms of mortality outcomes,our findings favor conducting low-dose CT screening in urban China.However,approaches to reducing false diagnoses and optimizing important screening conditions such as enrollment criteria for screening are highly needed.     

Long-term prognosis of patients with lung cancer detected on low-dose chest computed tomography screening

The effectiveness of lung cancer screening using low-dose chest computed tomography (CT) remains elusive. The present study examined the prognosis of patients with lung cancer detected on CT screening in Japanese men and women. Subjects were 210 patients with primary lung cancer identified on CT screening at two medical facilities in Hitachi, Japan, where a total of 61,914 CT screenings were performed among 25,385 screenees between 1998 and 2006. Prognostic status of these patients was sought by examining medical records at local hospitals, supplemented by vital status information from local government. The 5-year survival rate was estimated according to the characteristics of patients and lung nodule. A total of 203 (97%) patients underwent surgery. During a 5.7-year mean follow-up period, 19 patients died from lung cancer and 6 died from other causes. The estimated 5-year survival rate for all patients and for those on stage IA was 90% and 97%, respectively. Besides cancer stage, smoking and nodule appearance were independent predictors of a poor survival; multivariable-adjusted hazard ratio (95% confidence interval) was 4.7 (1.3, 16.5) for current and past smokers versus nonsmokers and 4.6 (1.6, 13.9) for solid nodule versus others. Even patients with solid shadow had a 5-year survival of 82% if the lesion was 20 mm or less in size. Results suggest that lung cancers detected on CT screening are mostly curative. The impact of CT screening on mortality at community level needs to be clarified by monitoring lung cancer deaths.     

Different efficacy of CT screening for lung cancer according to histological type: analysis of Japanese-smoker cases detected using a low-dose CT screen

The efficacy of CT screening for lung cancers is still a controversial issue, although one of the recently publicized large randomized controlled trials of this methodology, the National Lung Screening Trial (NLST), reported a decrease in the lung cancer-specific mortality for heavy smokers. We here performed case-matched comparative analyses, as a retrospective study, of three lung cancer arms detected by CT screen, X-ray screen, and by individual analysis of the clinicopathological features and outcomes in smokers from a symptomatic-prompted group of patients. We also considered the impacts of various potential biases in this cohort. The total study cohort comprised 136 patients in the CT screen group, 263 in the X-ray screen group and 254 in the symptomatic-prompted group. The ratio of stage IA cancers in the CT screen group was 67.7% and the ratio of advanced cases (i.e. stages IIIB + IV) was 12.5%. The percentage of bronchioloalveolar carcinoma (BAC) was 28.7% in the CT screen group. The 5-year survival rates were 82.4% in the CT screen group, 38.0% in the X-ray screen group and 17.8% in the symptomatic-prompted group. CT screening was found to be an independent prognostic factor for lung cancer even when BAC cases were eliminated (HR 0.35, P < 0.01). Based on our sub-analysis by individual histological sub-type, CT screen lung cancer cases had a better survival rate than non-screened patients, which included adenocarcinoma, squamous cell carcinoma and large/small cell carcinoma. However, by multi-variant analysis a CT scan would not be expected to reduce the risk of lung cancer mortality in patients with large/small cell carcinoma, although would be expected to reduce the risk of lung cancer death by 80% in cases of both adenocarcinoma and squamous cell carcinoma. In conclusion, our current findings indicate that CT screening for lung cancer is an effective strategy for smokers and that patients with adenocarcinoma and squamous cell carcinoma of all variant histological types may benefit from this test. In this regard, early stage large/small cell carcinomas are insufficiently detected by the existing annual screening system.     

Results of three-year mass screening programme for lung cancer using mobile low-dose spiral computed tomography scanner

The aim of this study was to evaluate the usefulness of annual screening for lung cancer by low-dose computed tomography (CT) and the characteristics of identified lung cancers. Subjects consisted of 5483 general population aged 40-74 years, who received initial CT scans in 1996, followed by repeat annual scans for most subjects in 1997 and 1998, with a total of 13 786 scans taken during 1996-1998. Work-up examinations for patients with suspicious lesions were conducted using diagnostic CTs. The initial screening in 1996 detected suspicious nodules in 279 (5.1%) of 5483 subjects, and 22 (8%) were confirmed surgically to have lung cancer. Corresponding figures in 1997 and 1998 screening studies were 173 (3.9%) of 4425 and 25 (14%) of 173, and 136 (3.5%) of 3878 and 9 (7%) of 136, respectively. The sensitivity and specificity of detecting surgically confirmed lung cancer were 55% (22/40) and 95% (4960/5199) in 1996 and 83% (25/30) and 97% (4113/4252) in 1997 screening, respectively. 88% (55/60) of lung cancers identified on screening and surgically confirmed were AJCC stage IA. Our trial allowed detection of nearly 11 times the expected annual number of early lung cancers. Repeat CT allowed the detection of more aggressive, rapidly growing lung cancers, compared to those in the initial screening.