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

Facing an un-met need in lung cancer screening: The never smokers

Lung cancer (LC) is the leading cause of cancer-related deaths worldwide and the second most common cancer in both men and women. In addition to smoking, other risk factors, such as environmental tobacco smoke, air pollution, biomass combustion, radon gas, occupational exposure, lung disease, family history of cancer, geographic variability, and genetic factors, play an essential role in developing LC. Current screening guidelines and eligibility criteria have limited efficacy in identifying LC cases (50 %), as most screening programs primarily target subjects with a smoking history as the leading risk factor. Implementing LC screening programs in people who have never smoked (PNS) can significantly impact cancer-specific survival and early disease detection. However, the available evidence regarding the feasibility and effectiveness of such programs is limited. Therefore, further research on LC screening in PNS is warranted to determine the necessary techniques for accurately identifying individuals who should be included in screening programs.

Managing Persistent Subsolid Nodules in Lung Cancer: Education, Decision Making, and Impact of Interval Growth Patterns

With the popularization of lung cancer screening, many persistent subsolid nodules (SSNs) have been identified clinically, especially in Asian non-smokers. However, many studies have found that SSNs exhibit heterogeneous growth trends during long-term follow ups. This article adopted a narrative approach to extensively review the available literature on the topic to explore the definitions, rationale, and clinical application of different interval growths of subsolid pulmonary nodule management and follow-up strategies. The development of SSN growth thresholds with different growth patterns could support clinical decision making with follow-up guidelines to reduce over- and delayed diagnoses. In conclusion, using different SSN growth thresholds could optimize the follow-up management and clinical decision making of SSNs in lung cancer screening programs. This could further reduce the lung cancer mortality rate and potential harm from overdiagnosis and over management.

Low-Dose Computed Tomography (LDCT) Lung Cancer Screening in Asian Female Never-Smokers Is as Efficacious in Detecting Lung Cancer as in Asian Male Ever-Smokers: A Systematic Review and Meta-Analysis

INTRODUCTION

Lung cancer in never-smokers is the major cancer cause of death globally. We compared the efficacy of low-dose computed tomography (LDCT) lung cancer screening among never-smokers versus ever-smokers using systematic review and meta-analysis.

METHODS

LDCT lung cancer screening studies that simultaneously included both ever-smoker and never-smoker participants published by April 30, 2021, were searched through PubMed and Scopus. Primary outcome measure was relative risk (RR) of lung cancer diagnosed among never-smokers versus ever-smokers.

RESULTS

A total of 14 studies (13 from Asia) were included (141,396 ever-smokers, 109,251 never-smokers, 1961 lung cancer cases diagnosed). RR of lung cancer diagnosed between ever-smokers versus never-smokers overall was 1.21 (95% confidence interval [CI]: 0.89-1.65), 1.37 (95% CI: 1.08-1.75) among males, and 0.88 (95% CI: 0.59-1.31) among females. RR was 1.78 (95% CI: 1.41-2.24) and 1.22 (95% CI: 0.89-1.68) for Asian female never-smokers versus male never-smokers and versus male ever-smokers, respectively, and 0.99 (95% CI: 0.65-1.50) versus high-risk ever-smokers (≥30 pack-years). Proportional meta-analysis revealed significantly more lung cancers diagnosed at first scan (95.4% [95% CI: 84.9-100.0] versus 70.9% [95% CI: 54.6-84.9], p = 0.010) and at stage 1 (88.5% [95% CI: 79.3-95.4] versus 79.7% [95% CI: 71.1-87.4], p = 0.071) among never-smokers versus ever-smokers, respectively. RR of lung cancer death and 5-year all-cause mortality in never-smokers versus ever-smokers was 0.27 (95% CI: 0.1-0.55, p < 0.001) and 0.13 (95% CI: 0.05-0.33, p < 0.001), respectively.

CONCLUSIONS

The RR of lung cancer detected by LDCT screening among female never-smokers and male ever-smokers in Asia was statistically similar. Overall and lung cancer specific mortality from the lung cancer diagnosed from LDCT screening was significantly reduced among never-smokers compared to ever-smokers.

Clinical features and surgical outcomes of young patients with lung adenocarcinoma manifesting as ground glass opacity

Background

More and more ground glass opacity associated lung adenocarcinoma (GGO-LUAD) have been diagnosed in young patients nowadays. Our study aims to investigate the clinical features and surgical outcomes of young patients with GGO-LUAD.

Methods

Patients aged ≤ 40 years who were diagnosed as lung adenocarcinoma and who underwent video assisted thoracoscopic surgery (VATS) were retrospectively reviewed from January 2017 to December 2018. According to radiological appearance of the patient’s lesions, they were divided into a solid nodule (SN) group and GGO group. The pathological subtypes, surgical procedures and nodules size were analyzed, and the clinical features and prognosis were evaluated between these patients.

Results

A total of 165 patients were included, of which 133 were in the GGO group and 32 in the SN group. Both the GGO group and the SN group had a higher proportion of females and non-smokers. Compared with patients (15.63%) in the SN group, there are more patients (27.8%) under the age of 30 in the GGO group. Pathological findings showed 83.5% of lesions were pre-invasive lesions in the GGO group, although 16.5% of lesions were invasive adenocarcinoma, whereas in the SN group, 96.9% were invasive adenocarcinoma. The GGO group had significantly better histological characteristics and prognosis than the SN group. Perioperative complications occurred in only 6 patients, including pneumonia in one patient, pneumothorax in two patients, and prolonged air leak in three patients. No other serious complications or deaths occurred. After a median follow-up time of 41.2 ± 7.2 months (32-56), the 3-year recurrence free survival (RFS) (100%) and overall survival (OS) (100%) of the GGO group were significantly higher than those (93.42% and 96.88%) in the SN group.

Conclusions

Young patients with GGO-LUAD are mainly non-smokers and female. Most of these patients were early-stage with good prognosis after surgery.

Generative models improve radiomics performance in different tasks and different datasets: An experimental study

PURPOSE

Radiomics is an active area of research focusing on high throughput feature extraction from medical images with a wide array of applications in clinical practice, such as clinical decision support in oncology. However, noise in low dose computed tomography (CT) scans can impair the accurate extraction of radiomic features. In this article, we investigate the possibility of using deep learning generative models to improve the performance of radiomics from low dose CTs.

METHODS

We used two datasets of low dose CT scans - NSCLC Radiogenomics and LIDC-IDRI - as test datasets for two tasks - pre-treatment survival prediction and lung cancer diagnosis. We used encoder-decoder networks and conditional generative adversarial networks (CGANs) trained in a previous study as generative models to transform low dose CT images into full dose CT images. Radiomic features extracted from the original and improved CT scans were used to build two classifiers - a support vector machine (SVM) and a deep attention based multiple instance learning model - for survival prediction and lung cancer diagnosis respectively. Finally, we compared the performance of the models derived from the original and improved CT scans.

RESULTS

Denoising with the encoder-decoder network and the CGAN improved the area under the curve (AUC) of survival prediction from 0.52 to 0.57 (p-value < 0.01). On the other hand, the encoder-decoder network and the CGAN improved the AUC of lung cancer diagnosis from 0.84 to 0.88 and 0.89 respectively (p-value < 0.01). Finally, there are no statistically significant improvements in AUC using encoder-decoder networks and CGAN (p-value = 0.34) when networks trained at 75 and 100 epochs.

CONCLUSION

Generative models can improve the performance of low dose CT-based radiomics in different tasks. Hence, denoising using generative models seems to be a necessary pre-processing step for calculating radiomic features from low dose CTs.

Descriptive study of chest x-ray examination in mandatory annual health examinations at the workplace in Japan

The utility of chest x-ray examination (CXR) in mandatory annual health examinations for occupational health is debatable in Japan. This study aimed to provide basic data to consider future policies for mandatory annual health examinations in the workplace. A nationwide descriptive survey was performed to determine the rate of detection of tuberculosis, lung cancer, and other diseases through CXR in organizations associated with National Federation of Industrial Health Association. The rate of finding on CXR conducted during annual health examinations in FY2016 was evaluated. Data regarding diagnosis based on follow-up examination findings were obtained and compared with the national statistics. In addition, CXR findings were compared with the results of low-dose lung computed tomography performed at the Hitachi Health Care Center. From 121 surveyed institutions, 88 institutions with 8,669,403 workers were included. For all ages, 1.0% of examinees required follow-up examination. Among 4,764,985 workers with diagnosis data, the tuberculosis detection rate was 1.8–5.3 per 100,000 persons. For Lung cancer, 3,688,396 workers were surveyed, and 334 positive cases were detected. The lung cancer detection rate using CXR was 9.1–24.4 per 100,000 persons. From 164 cases with information regarding the clinical stage, 72 (43.9%) had Stage I lung cancer. From 40,045 workers who underwent low-dose computed tomography multiple times, 31 lung cancer cases, all with Stage I disease, were detected (detection rate: 77.4 per 100,000 persons). Our findings suggest that CXR plays a little role in the detection of active tuberculosis. With regard to LC screening, the detection rate of LC by CXR was lower, approximately 50%, than the expected rate (41.0 per 100,000 persons) of LC morbidity based on the age–sex distribution of this study population. However, the role of CXR for LC screening cannot be mentioned based on this result, because assessment of mortality reduction is essential to evaluate the role.

Landscape on CT screening for lung cancer in Asia

Lung cancer remains the leading cause of cancer incidence and mortality worldwide. Approximately 60% of the world's new cases of lung cancer and deaths from it are expected in Asia in 2018. Currently, lung cancer screening using low-dose computed tomography (LDCT) is recommended for heavy smokers in North America, Europe and some countries in Asia. Tobacco smoking being the major risk factor for lung cancer, but in Asia, lung cancer in never-smokers (LCINS) is also a concern. This paper reviews on lung cancer incidence, mortality, etiology, smoking in Asia, and systematic reviews on LDCT lung cancer screening studies, including ongoing projects and recommendation on lung cancer screening in Asia. Some of the earliest studies of LDCT lung cancer screening worldwide were in Asia. Many countries in Asia have developed LDCT screening studies in various high-risk participants. Currently, there are several ongoing large-scale lung cancer screening trials to evaluate the efficacy of LDCT screening for never-smokers and light smokers, as well as heavy smokers, and to evaluate the feasibility of population-based LDCT lung cancer screening.

Clinical characteristics and prognosis of ground-glass opacity nodules in young patients

Background

The detection rate of ground-glass opacity (GGO) in young patients has increased year by year with the increasingly widespread use of high-resolution computed tomography (HRCT) and the increased resolution of HRCT imaging. However, no scholars have reported the clinical characteristics and prognosis of GGO in young patients systematically. The purpose of this study is to investigate the clinical characteristics and prognosis presenting as GGO in young patients.

Methods

Clinical data of 127 young patients who were diagnosed as GGO and who underwent video-assisted thoracoscopic surgery (VATS) and had routine pathological examination were collected from January 2016 to January 2017. Nodules were classified according to benign and malignant: 26 benign nodules (Group A) and 115 malignant nodules (Group B). The pathological types, nodules size, surgical methods were analyzed, and the clinical characteristics and prognosis were evaluated.

Results

The results of pathological examination of 91 pure ground-glass opacities (pGGOs) revealed 16 adenocarcinoma in situs (AISs), 42 micro invasive adenocarcinomas (MIAs), 13 invasive adenocarcinomas (IAs), 8 atypical adenomatous hyperplasias (AAHs), 1 inflammatory granuloma, 2 pulmonary inflammatory pseudotumors (IPTs) and 9 other benign nodules. The results of pathological examination of 50 mixed ground-glass opacities (mGGOs) revealed 6 AISs, 29 MIAs, 9 IAs, 1 AAH, 2 inflammatory granulomas and 3 other benign nodules. All patients had no lymph nodes invasion. The rates of perioperative complications were 6.30%, compared to 7.63% for long-term complications. None of the patients with GGO experienced a recurrence and death [2-year recurrence-free survival (RFS), 100%; 2-year overall survival (OS), 100%].

Conclusions

The GGO in young patients that received VATS has a high proportion of malignant, its prognosis is satisfied.

A population-based cohort study to evaluate the effectiveness of lung cancer screening using low-dose CT in Hitachi city, Japan

Objectives

To evaluate the effectiveness of lung cancer screening using low-dose computed tomography for the general population, we conducted a retrospective cohort study of screening for participants among Hitachi residents.

Materials and Methods

Citizens aged 50-74 who underwent low-dose computed tomography screening at least once during 1998-2006 were defined as the computed tomography group, and those who underwent X-ray screening at least once during the same period, but did not receive low-dose computed tomography screening throughout the follow-up period, were defined as the XP group. We investigated the lung cancer incidence rate, mortality rate and all-cause mortality rate for both groups from the first lung cancer screening to the end of 2012.

Results

In the computed tomography group (17 935 residents; 9790 males and 8145 females), 273 cases of lung cancer (1.5%), 72 cases of lung cancer death (0.4%), and 885 cases of all-cause death (4.9%) were observed. On the other hand, 164 cases (1.1%) of lung cancer, 80 cases (0.5%) of lung cancer death and 1188 cases (7.6%) of all-cause death were observed in the XP group (15 548 residents; 6526 males and 9022 females). The hazard ratios of the computed tomography group to the XP group adjusted for gender, age and smoking history were 1.23 for lung cancer incidence rate, 0.49 for lung cancer mortality rate and 0.57 for all-cause mortality rate. Non-smokers and light smokers (<30 pack-years) had a significantly lower lung cancer mortality (0.41 and 0.21, respectively).

Conclusion

low-dose computed tomography screening for a population including non-smokers and light smokers may be effective.

Clinical and radiological characteristics of central pulmonary adenocarcinoma: a comparison with central squamous cell carcinoma and small cell lung cancer and the impact on treatment response

Purpose

The proportion of central pulmonary adenocarcinoma (ADC) in central-type lung cancer has been gradually increasing due to the overall increasing incidence of pulmonary ADC. But the clinical and radiological characteristics of central ADCs remain unclear. In this study, we compared the clinical and radiological characteristics of central ADCs with those of small cell lung cancers (SCLCs) and squamous cell carcinomas (SQCCs) and investigated the impact of these characteristics on patients’ treatment response.

Patients and methods

The medical records of 302 consecutive patients with central lung cancer from July 2014 to September 2016 were retrospectively reviewed. There were 99 patients with ADC, 95 with SQCC and 108 with SCLC. Computed tomography images were interpreted by two radiologists. Treatment response was determined by Response Evaluation Criteria In Solid Tumors 1.1.

Results

Univariate analyses found that younger age, female sex, no history of smoking, higher levels of carcinoembryonic antigen (CEA), contralateral hilum lymphadenopathy, contralateral lung metastasis, pleural nodules and pleural metastasis to the interlobular fissure were significantly correlated with central ADC. Multivariate logistic regression analyses revealed that compared with central SQCC, female sex, younger age, no history of smoking, higher levels of CEA and contralateral hilum lymphadenopathy were the significantly independent indicators of central pulmonary ADC. Furthermore, compared with central SCLC, younger age, higher levels of CEA and cytokeratin 19 fragment (Cyfra21-1), lower levels of neuron-specific enolase, pleural nodules and lack of vascular involvement were significantly associated with central ADC. In 85 central ADC patients who received first-line platinum-based chemotherapy, both univariate and multivariate logistic regression analyses revealed that pulmonary emphysema had a negative correlation with treatment response (odds ratio=8.04, p=0.02).

Conclusion

Our study revealed that central pulmonary ADCs exhibited more aggressive clinical and radiological characteristics. Pulmonary emphysema was an independent and negative indicator for treatment response of central ADC.

Comparison of computer-aided detection (CADe) capability for pulmonary nodules among standard-, reduced- and ultra-low-dose CTs with and without hybrid type iterative reconstruction technique

PURPOSE

To directly compare the effect of a reconstruction algorithm on nodule detection capability of the computer-aided detection (CADe) system using standard-dose, reduced-dose and ultra-low dose chest CTs with and without adaptive iterative dose reduction 3D (AIDR 3D).

MATERIALS AND METHODS

Our institutional review board approved this study, and written informed consent was obtained from each patient. Standard-, reduced- and ultra-low-dose chest CTs (250 mA, 50 mA and 10 mA) were used to examine 40 patients, 21 males (mean age ± standard deviation: 63.1 ± 11.0 years) and 19 females (mean age, 65.1 ± 12.7 years), and reconstructed as 1 mm-thick sections. Detection of nodule equal to more than 4 mm in dimeter was automatically performed by our proprietary CADe software. The utility of iterative reconstruction method for improving nodule detection capability, sensitivity and false positive rate (/case) of the CADe system using all protocols were compared by means of McNemar's test or signed rank test.

RESULTS

Sensitivity (SE: 0.43) and false-positive rate (FPR: 7.88) of ultra-low-dose CT without AIDR 3D was significantly inferior to those of standard-dose CTs (with AIDR 3D: SE, 0.78, p < .0001, FPR, 3.05, p < .0001; and without AIDR 3D: SE, 0.80, p < .0001, FPR: 2.63, p < .0001), reduced-dose CTs (with AIDR 3D: SE, 0.81, p < .0001, FPR, 3.05, p < .0001; and without AIDR 3D: SE, 0.62, p < .0001, FPR: 2.95, p < .0001) and ultra-low-dose CT with AIDR 3D (SE, 0.79, p < .0001, FPR, 4.88, p = .0001).

CONCLUSION

The AIDR 3D has a significant positive effect on nodule detection capability of the CADe system even when radiation dose is reduced.

Lung Cancer Screening with Low-Dose CT in Female Never Smokers: Retrospective Cohort Study with Long-term National Data Follow-up

Purpose

Because of growing concerns about lung cancer in female never smokers, chest low-dose computed tomography (LDCT) screening is often performed although it has never shown clinical benefits. We examinewhether or not female never smokers really need annual LDCT screening when the initial LDCT showed negative findings.

Materials and Methods

This retrospective cohort study included 4,365 female never smokers aged 40 to 79 years who performed initial LDCT from Aug 2002 to Dec 2007. Lung cancer diagnosis was identified from the Korea Central Cancer Registry Database registered until December 31, 2013. We calculated the incidence, cumulative probability, and standardized incidence ratio (SIR) of lung cancer by Lung Imaging Reporting and Data System (Lung-RADS) categories showed on initial LDCT.

Results

After median follow-up of 9.69 years, 22 (0.5%) had lung cancer. Lung cancer incidence for Lung-RADS category 4 was 1,848.4 (95% confidence interval [CI], 1,132.4 to 3,017.2) per 100,000 person-years and 16.4 (95% CI, 7.4 to 36.4) for categories 1, 2, and 3 combined. The cumulative probability of lung cancer for category 4 was 10.6% at 5 years and 14.8% at 10 years while they were 0.07% and 0.17% when categories 1, 2, and 3 were combined. The SIR for subjects with category 4 was 43.80 (95% CI, 25.03 to 71.14), which was much higher than 0.47 (95% CI, 0.17 to 1.02) for categories 1, 2, and 3 combined.

Conclusion

Considering the low risk of lung cancer development in female never smokers, it seems unnecessary to repeat annual LDCT screening for at least 5 years or even longer unless the initial LDCT showed Lung-RADS category 4 findings.

The UK Lung Cancer Screening Trial: a pilot randomised controlled trial of low-dose computed tomography screening for the early detection of lung cancer

BACKGROUND

Lung cancer kills more people than any other cancer in the UK (5-year survival < 13%). Early diagnosis can save lives. The USA-based National Lung Cancer Screening Trial reported a 20% relative reduction in lung cancer mortality and 6.7% all-cause mortality in low-dose computed tomography (LDCT)-screened subjects.

OBJECTIVES

To (1) analyse LDCT lung cancer screening in a high-risk UK population, determine optimum recruitment, screening, reading and care pathway strategies; and (2) assess the psychological consequences and the health-economic implications of screening.

DESIGN

A pilot randomised controlled trial comparing intervention with usual care. A population-based risk questionnaire identified individuals who were at high risk of developing lung cancer (≥ 5% over 5 years).

SETTING

Thoracic centres with expertise in lung cancer imaging, respiratory medicine, pathology and surgery: Liverpool Heart & Chest Hospital, Merseyside, and Papworth Hospital, Cambridgeshire.

PARTICIPANTS

Individuals aged 50-75 years, at high risk of lung cancer, in the primary care trusts adjacent to the centres.

INTERVENTIONS

A thoracic LDCT scan. Follow-up computed tomography (CT) scans as per protocol. Referral to multidisciplinary team clinics was determined by nodule size criteria.

MAIN OUTCOME MEASURES

Population-based recruitment based on risk stratification; management of the trial through web-based database; optimal characteristics of CT scan readers (radiologists vs. radiographers); characterisation of CT-detected nodules utilising volumetric analysis; prevalence of lung cancer at baseline; sociodemographic factors affecting participation; psychosocial measures (cancer distress, anxiety, depression, decision satisfaction); and cost-effectiveness modelling.

RESULTS

A total of 247,354 individuals were approached to take part in the trial; 30.7% responded positively to the screening invitation. Recruitment of participants resulted in 2028 in the CT arm and 2027 in the control arm. A total of 1994 participants underwent CT scanning: 42 participants (2.1%) were diagnosed with lung cancer; 36 out of 42 (85.7%) of the screen-detected cancers were identified as stage 1 or 2, and 35 (83.3%) underwent surgical resection as their primary treatment. Lung cancer was more common in the lowest socioeconomic group. Short-term adverse psychosocial consequences were observed in participants who were randomised to the intervention arm and in those who had a major lung abnormality detected, but these differences were modest and temporary. Rollout of screening as a service or design of a full trial would need to address issues of outreach. The health-economic analysis suggests that the intervention could be cost-effective but this needs to be confirmed using data on actual lung cancer mortality.

CONCLUSIONS

The UK Lung Cancer Screening (UKLS) pilot was successfully undertaken with 4055 randomised individuals. The data from the UKLS provide evidence that adds to existing data to suggest that lung cancer screening in the UK could potentially be implemented in the 60-75 years age group, selected via the Liverpool Lung Project risk model version 2 and using CT volumetry-based management protocols.

FUTURE WORK

The UKLS data will be pooled with the NELSON (Nederlands Leuvens Longkanker Screenings Onderzoek: Dutch-Belgian Randomised Lung Cancer Screening Trial) and other European Union trials in 2017 which will provide European mortality and cost-effectiveness data. For now, there is a clear need for mortality results from other trials and further research to identify optimal methods of implementation and delivery. Strategies for increasing uptake and providing support for underserved groups will be key to implementation.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN78513845.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 40. See the NIHR Journals Library website for further project information.

Low-dose computed tomography screening in Japan

Lung cancer is a leading cause of cancer death in both male and female individuals in Japan. The effect of screening using chest radiography is assumed to be limited. In Japan, screening using low-dose computed tomography (CT) was initiated in 1993, and its dissemination has progressed with studies evaluating its efficacy, although it is not officially recommended. In addition to the academic activities of the Japanese Society of CT Screening, certification of physicians and radiologic technologists by the Japan Accreditation Council for CT Screening has been progressing. Currently, several hundred thousand low-dose CT screenings are performed annually in Japan. In Hitachi City, Ibaraki Prefecture, low-dose CT screening among employees and in communities started in 2001, and it was estimated that 40% of 50- to 69-year-old citizens had undergone screening at least once by March 2009. The lung cancer mortality rate in citizens in this age group decreased by 24% in 2005 to 2009 compared with the national statistics. Low-dose CT screening targeting the general population may be effective, but it is necessary to consider the target and interval of screening separately from those for the high-risk group. Observational study may play a role in evaluating the efficacy of screening in Japan.

A meta-analysis: is low-dose computed tomography a superior method for risky lung cancers screening population?

BACKGROUND AND AIMS

Low-dose computed tomography (LDCT) has been proposed to be a new screening method to discover lung cancers in an early stage, especially those patients who are in a high risk of lung cancer. The primary objective of this meta-analysis is to systematically review the effect of LDCT on screening for lung cancers among the risky population who are older than 49 years old and with smoking exposure.

METHODS

We searched randomized controlled clinical trials (RCTs) about comparing LDCT and chest X-ray or usual caring from MEDLINE, EMBASE, and the Cochrane Library, Web of Knowledge and SpringerLink databases (January 1994 to September 2013).

RESULTS

Nine RCTs met criteria for inclusion. Screening for lung cancer using LDCT resulted in a significantly higher number of stage I lung cancers [odds ratio (OR) 2.15, 95% confidence interval (CI) 1.88-2.47], higher number of total lung cancers (OR 1.31, 95% CI 1.20-1.43) than the control. Four of the nine studies indicated that the screening method did not decrease all-cause mortality (OR 0.96, 95% CI 0.90-1.02), but decreased lung cancer-specific mortality (OR 0.84, 95% CI 0.74-0.96). Five studies showed that LDCT had higher false-positive rates (OR 8.7, 95% CI 7.43-10.19) than the group of control.

CONCLUSION

Among the risky population, LDCT screening find out more stage I lung cancers and total lung cancers compared with chest X-ray or no screening, and also shows advantages in decreasing lung cancer-specific mortality, but the screening method does not decrease all-cause mortality and have a higher false-positive rates in diagnosis.

From randomized trials to the clinic: is it time to implement individual lung-cancer screening in clinical practice? A multidisciplinary statement from French experts on behalf of the French intergroup (IFCT) and the groupe d'Oncologie de langue francaise (GOLF)

Background

Despite advances in cancer therapy, mortality is still high except in early-stage tumors, and screening remains a challenge. The randomized National Lung Screening Trial (NLST), comparing annual low-dose computed tomography (LDCT) and chest X-rays, revealed a 20% decrease in lung-cancer-specific mortality. These results raised numerous questions. The French intergroup for thoracic oncology and the French-speaking oncology group convened an expert group to provide a coherent outlook on screening modalities in France.

Methods

A literature review was carried out and transmitted to the expert group, which was divided into three workshops to tackle specific questions, with responses presented in a plenary session. A writing committee drafted this article.

Results

The multidisciplinary group favored individual screening in France, when carried out as outlined in this article and after informing subjects of the benefits and risks. The target population involves subjects aged 55–74 years, who are smokers or have a 30 pack-year smoking history. Subjects should be informed about the benefits of quitting. Screening should involve LDCT scanning with specific modalities. Criteria for CT positivity and management algorithms for positive examinations are given.

Conclusions

Individual screening requires rigorous assessment and precise research in order to potentially develop a lung-cancer screening policy.

A decrease in lung cancer mortality following the introduction of low-dose chest CT screening in Hitachi, Japan

Recent US clinical trial demonstrated that CT screening prevents lung cancer death among high risk individuals. However, it remains unclear whether wide implementation of low-dose CT screening for lung cancer can decrease mortality in the community. Among residents in Hitachi City (Japan), where nearly 40% of inhabitants aged 50-69 years were estimated to have participated in the screening at least once from 1998 through 2009, the trend of lung cancer mortality was described in relation to the timing of implementation of the CT screening. Cancer mortality data were obtained from regional cancer registry and standardized mortality ratio (SMR) of lung cancer was calculated for each 5-year period during 1995-2009. In both men and women aged 60 years or older, age-specific lung cancer mortality rates were generally lower during 2005-2009 as compared with those during 1995-2004. For combined men and women aged 50-79 years, SMR was nearly unity prior to or during introductory phase of CT screening and during early period of implementation; however, it was significantly decreased during 2005-2009, well after the implementation of CT screening, with SMR (95% confidence interval) being 0.76 (0.67-0.86). Results suggest that wide implementation of low-dose chest CT screening may decrease lung cancer mortality in the community 4-8 years after introduction of the screening.