Computed Tomography Screening Program Research Articles

Cytisine Therapy Improved Smoking Cessation in the Randomized Screening and Multiple Intervention on Lung Epidemics Lung Cancer Screening Trial

IntroductionCytisine, a partial agonist-binding nicotine acetylcholine receptor, is a promising cessation intervention. We conducted a single-center, randomized, controlled trial (RCT) in Italy to assess the efficacy and tolerability of cytisine as a smoking cessation therapy among lung cancer screening participants. MethodsFrom July 2019 to March 2020, the Screening and Multiple Intervention on Lung Epidemics RCT enrolled 869 current heavy tobacco users in a low-dose computed tomography screening program, with a randomized comparison of pharmacologic intervention with cytisine plus counseling (N = 470) versus counseling alone (N = 399). The primary outcome was continuous smoking abstinence at 12 months, biochemically verified through carbon monoxide measurement. ResultsAt the 12-month follow-up, the quit rate was 32.1% (151 participants) in the intervention arm and 7.3% (29 participants) in the control arm. The adjusted OR of continuous abstinence was 7.2 (95% confidence interval: 4.6–11.2). Self-reported adverse events occurred more frequently in the intervention arm (399 events among 196 participants) than in the control arm (230 events among 133 participants, p < 0.01). The most common adverse events were gastrointestinal symptoms, comprising abdominal swelling, gastritis, and constipation. ConclusionsThe efficacy and safety observed in the Screening and Multiple Intervention on Lung Epidemics RCT indicate that cytisine, a very low-cost medication, is a useful treatment option for smoking cessation and a feasible strategy to improve low-dose computed tomography screening outcomes with a potential benefit for all-cause mortality.

Results of 10-year mobile low-dose computed tomography screenings for lung cancer in Shimane, Japan.

Some randomized controlled trials have evaluated the effects of low-dose computed tomography (CT) screening on lung cancer mortality in heavy smokers. Based on the results of those trials, our CT screening program recommended screening for people aged ≥40 years with a history of smoking. This retrospective study aimed to verify the validity of our CT screening program and elucidate the current state of CT screening program. We retrospectively examined lung cancer detection in 25,189 participants who underwent chest CT screening by a mobile low-dose CT screening unit in the 10-year period from April 2009 to March 2019. Participants were recruited at Japan Agricultural Cooperatives (JA) Shimane Kouseiren. Participants requested CT screening for lung cancer. CT images were read by two pulmonologists. Lung cancer was identified in 82 of the 25,189 participants over 10 years, an overall lung cancer detection rate (percentage of lung cancers detected among all participants) of 0.33%. Lung cancer among never smokers accounted for 54.9% of the detected cases. The lung cancer detection rate was similar for smokers versus never smokers. The stage IA detection rate (percentage of stage IA lung cancers among all lung cancers detected) was 62%, while the stage Ⅳ detection rate was 10%. Chest CT detected lung cancer in never smokers as well as current or former smokers. Our CT screening program was not effective for never smokers; thus, further study of the effectiveness of CT screening in never smokers is needed.

Patient Adherence in an Academic Medical Center's Low-dose Computed Tomography Screening Program.

Low-dose computed tomography (LDCT) screening is an important tool for reducing lung cancer mortality. This study describes a single center's experience with LDCT and attempts to identify any barriers to compliance with standard guidelines. This is a retrospective review of a single university-based hospital system from 2015 to 2019. All individuals who met eligibility for lung cancer screening were entered into a database. The definition of adherence with the screening program was determined by the recommended timeline for the follow-up LDCT. Cohorts were split by adherence and demographics were compared. A total of 203 LDCTs were performed in 121 patients who met eligibility for LDCT and had appropriate surveillance from 2015 to 2019. The average age was 64 years old. The overall adherence rate for prescribed LDCTs was 59.1%. Patients with Lung-RADS score 2 had 2.43 times higher odds of adherence relative to patients with Lung-RADS score 1 (odds ratio [OR]=2.43; 95% confidence interval [CI]: 1.23-4.83; P=0.011). African American patients had 42% lower odds of adherence relative to white patients (OR=0.58; 95% CI: 0.32-1.06; P=0.076). Patients with non-District of Columbia zip codes had 57% higher odds of adherence relative to those with District of Columbia zip codes, although this did not reach statistical significance (OR=1.57; 95% CI: 0.87-2.82; P=0.136). Despite the implementation of a multidisciplinary, academic LDCT screening program, overall adherence rate to prescribed follow-up scans was suboptimal. Socioeconomic disparities and African American race may negatively affect adherence to lung cancer screening LDCT guidelines. Patients with concerning findings on initial LDCT had a higher association of adherence to guidelines.

Feasibility of electromagnetic navigation bronchoscopy-guided lung resection for pulmonary ground-glass opacity nodules.

BackgroundRecent advances in imaging modalities and recommended low-dose computed tomography screening programs have made it easier to diagnose early lung cancer. However, the diagnosis of small ground-glass nodules (GGNs) has been problematic due to inappropriate specimen procurement and failure of conventional percutaneous core needle biopsy. Thus, we aimed to evaluate the usefulness of electromagnetic navigation bronchoscopy (ENB)-guided video-assisted lung resection for not only the diagnosis but also treatment of GGNs.MethodsFrom 2017 to 2019, 110 patients with suspicious lung cancer lesions that were not diagnosed by conventional procedure underwent ENB-guided lung resection. Among 35 cases of GGNs, 33 cases of localization were included in this study (two cup biopsy cases were excluded). We used SuperDimension™ for the ENB procedure. After general anesthesia, indigo carmine (0.3–0.5 mL) was injected, and GGNs were resected through video-assisted thoracoscopic surgery.ResultsOf the 33 GGNs, 16 were pure (2 adenocarcinomas in situ, 5 minimally invasive adenocarcinomas (MIAs), 3 adenocarcinomas, and 6 benign lesions) and 17 were mixed (1 MIA, 11 adenocarcinomas, and 5 benign lesions). The mean size of all lesions was 11.2±7.78 mm, mean distance to the pleura was 11.2±14.2 mm, and mean ENB procedure time was 18.8±8.88 minutes. Dye localization and surgical resection of GGN were successful in all cases. There was no procedure-related complication.ConclusionsENB is a feasible and highly accurate localization method for minimally invasive lung resection of small GGNs.

MS12.04 The International Lung Cancer Consortium (ILCCO), an International Study to Identify Risk Factors for Lung Cancer Development

The International Lung Cancer Consortium (ILCCO) was established in 2004 to maximize research efficiency for lung cancer and to share comparable epidemiological and clinical data, and biological samples across studies. Since its establishment, over 70 studies have participated in the ILCCO and shared comparable clinico-epidemiological data and a subset with biological samples and genomic data. The data harmonization was conducted at the Sinai Health System in Toronto, and genomic data is managed at the Dartmouth College of Medicine/Baylor College of Medicine. In total, the ILCCO Data Repository now has epidemiological data for over 1.2 million study participants, including 100,000 lung cancer patients, and genomic data on approximately 50,000 study participants. The large-scale epidemiological and genomic data allow us to extensively study and characterize the etiological factors, including lifestyle risk factors, medical history and genomic architectures for lung cancer development. Data submitted from all studies are systematically checked for missing values, outliers, inadmissible values, aberrant distributions and internal inconsistencies before harmonization. Common variable definitions were developed. For lifestyle risk factors and medical history, we conducted meta-analysis based on study-specific estimates, when applicable. If heterogeneities were present, random effects models were employed to account for the heterogeneity across studies. For subgroup of interests or when sample size is limited, pooled-analyses based on individual-level data were applied. When applicable, the non-linearity relationship was assessed. For genetic susceptibility of lung cancer, we investigated the genetic loci associated with lung cancer risk using log-additive model adjusted for population ancestry and account for multiple comparisons. To assess the causality of specific exposures and lung cancer risk, we applied Mendelian Randomization and mediation analytical approaches. To estimate 5-year lung cancer absolute risk, we incorporated risk factors, medical history and genetic factors based on age-specific lung cancer incidence and the competing risk. Based on 17 ILCCO studies (24,000 cases and 81,000 controls), we observed a robust association between lung cancer risk and emphysema and pneumonia, even among never smokers, and after long latency period. Based on 24 ILCCO studies, we quantified the association between family history of lung cancer and its risk by their smoking status and affected relative types. Based on 6 studies in UK, Canada, UK and New Zealand, we assessed the association between cannabis smoking and lung cancer risk by intensity, duration and cumulative exposures and by histological subtypes. We have recently completed a largest lung cancer genetic analysis based over 29,000 lung cancer cases and 56,000 controls. We identified 10 novel lung cancer susceptibility loci, in addition to the known regions, such as TERT/CLPTM1L, CHRNA5, MHC region, RAD52, CHEK2 and found specific associations mediated through mRNA expression. We helped to quantify the effect of specific genetic variant in nicotinic receptor gene on smoking cessation and age of onset. Using genetic instruments and Mendelian Randomization approach, we confirmed the association between lung cancer risk and long telomere length. Most recently, we investigated the association between impaired lung function and lung cancer risk based on UK Biobank and ILCCO OncoArray data, and we found that impaired lung function was associated with lung cancer risk in never smokers and particularly for adenocarcinoma, most likely through immune-mediated pathways. When combining all factors into an integrative risk model, we found that individuals with highly polygenic risk scores reached lung cancer screening threshold at younger age than those with average genetic risk background. ILCCO provides a powerful research platform for research on lung cancer. The collaborative projects based on ILCCO have contributed to the understanding of lung cancer etiology beyond tobacco smoking. As future perspectives, ILCCO has obtained clinical prognosis data for over 50,000 lung cancer patients and will also be able to investigate factors associated with lung cancer prognosis in depth. Finally, ILCCO has built close collaborations with several lung cancer low-dose computed tomography screening programs to jointly investigate the optimal strategy for risk stratification and early detection for lung cancer.

Preface for minimally invasive surgery for lung cancer.

With advancements in computed tomography screening program for early lung cancer, small lung nodules have been increasingly detected. Recently, uniportal and nonintubated VATS for major lung resections has become a revolution in the treatment of lung cancer.

P2.13-010 Five-Year-Long Follow-Up of the Low-Dose Computed Tomography Screening Program in Gdansk, Poland

P2.13-010 Five-Year-Long Follow-Up of the Low-Dose Computed Tomography Screening Program in Gdansk, Poland

Recommendations from the European Society of Thoracic Surgeons (ESTS) regarding computed tomography screening for lung cancer in Europe.

In order to provide recommendations regarding implementation of computed tomography (CT) screening in Europe the ESTS established a working group with eight experts in the field. On a background of the current situation regarding CT screening in Europe and the available evidence, ten recommendations have been prepared that cover the essential aspects to be taken into account when considering implementation of CT screening in Europe. These issues are: (i) Implementation of CT screening in Europe, (ii) Participation of thoracic surgeons in CT screening programs, (iii) Training and clinical profile for surgeons participating in screening programs, (iv) the use of minimally invasive thoracic surgery and other relevant surgical issues and (v) Associated elements of CT screening programs (i.e. smoking cessation programs, radiological interpretation, nodule evaluation algorithms and pathology reports). Thoracic Surgeons will play a key role in this process and therefore the ESTS is committed to providing guidance and facilitating this process for the benefit of patients and surgeons.

Panel of serum metabolites discriminates cancer patients and healthy participants of lung cancer screening - a pilot study

Blood biomarkers may support early diagnosis of lung cancer by enabling pre-selection of candidates for computed tomography screening or discrimination between benign and malignant screening-detected nodules. We aimed to identify features of serum metabolome distinguishing individuals with early-detected lung cancer from healthy participants of the lung cancer screening program. Blood samples were collected in the course of a low-dose computed tomography screening program performed in the Gdansk district (Northern Poland). The analysis included 31 patients with screening-detected lung cancer and the pair-matched group of 92 healthy controls. The gas chromatography coupled to mass spectrometry (GC/MS) approach was used to identify and quantify small metabolites present in serum. There were several metabolites detected in the sera whose abundances discriminated patients with lung cancer from controls. Majority of the differentiating components were downregulated in cancer samples, including amino acids, carboxylic acids and tocopherols, whereas benzaldehyde was the only compound significantly upregulated. A classifier including nine serum metabolites allowed separation of cancer and control samples with 100% sensitivity and 95% specificity. Signature of serum metabolites discriminating between cancer patients and healthy participants of the early lung cancer screening program was identified using a GC/MS metabolomics approach. This signature, though not validated in an independent dataset, deserves further investigation in a larger cohort study.

Community-Based Multidisciplinary Computed Tomography Screening Program Improves Lung Cancer Survival

Lung cancer is the most common cause of cancer deaths in the United States. Overall survival is less than 20%, with the majority of patients presenting with advanced disease. The National Lung Screening Trial, performed mainly in academic medical centers, showed that cancer mortality can be reduced with computed tomography (CT) screening compared with chest radiography in high-risk patients. To determine whether this survival advantage can be duplicated in a community-based multidisciplinary thoracic oncology program, we initiated a CT scan screening program for lung cancer within an established health care system. In 2008, we launched a lung cancer CT screening program within the WellStar Health System (WHS) consisting of five hospitals, three health parks, 140 outpatient medical offices, and 12 imaging centers that provide care in a five-county area of approximately 1.4 million people in Metro-Atlanta. Screening criteria incorporated were the International Early Lung Cancer Action Program (2008 to 2010) and National Comprehensive Cancer Network guidelines (2011 to 2013) for moderate- and high-risk patients. A total of 1,267 persons underwent CT lung cancer screening in WHS from 2008 through 2013; 53% were men, 87% were 50 years of age or older, and 83% were current or former smokers. Noncalcified indeterminate pulmonary nodules were found in 518 patients (41%). Thirty-six patients (2.8%) underwent a diagnostic procedure for positive findings on their CT scan; 30 proved to have cancer, 28 (2.2%) primary lung cancer and 2 metastatic cancer, and 6 had benign disease. Fourteen patients (50%) had their lung cancer discovered on their initial CT scan, 11 on subsequent scans associated with indeterminate pulmonary nodules growth and 3 patients who had a new indeterminate pulmonary nodules. Only 15 (54%) of these 28 patients would have qualified as a National Lung Screening Trial high-risk patient; 75% had stage I or II disease. Overall 5-year survival was 64% and 5-year cancer specific survival was 71% in the screened patients, whereas nonscreened lung cancer patients during that time in WHS had an overall survival of only 19% (p < 0.001). A community-based multidisciplinary lung cancer screening program can improve survival of patients with lung cancer outside of a large multicenter study. This survival advantage was caused by a significant stage shift to earlier disease. Lung cancer CT screening may also benefit patients not meeting the National Lung Screening Trial criteria who are at moderate or high risk for lung cancer.

Balancing curability and unnecessary surgery in the context of computed tomography screening for lung cancer

Surgical management is a critical component of computed tomography (CT) screening for lung cancer. We report the results for US sites in a large ongoing screening program, the International Early Lung Cancer Action Program (I-ELCAP). We identified all patients who underwent surgical resection. We compared the results before (1993-2005) and after (2006-2011) termination of the National Lung Screening Trial to identify emerging trends. Among 31,646 baseline and 37,861 annual repeat CT screenings, 492 patients underwent surgical resection; 437 (89%) were diagnosed with lung cancer; 396 (91%) had clinical stage I disease. In the 54 (11%) patients with nonmalignant disease, resection was sublobar in 48 and lobectomy in 6. The estimated cure rate based on the 15-year Kaplan-Meier survival for all 428 patients (excluding 9 typical carcinoids) with lung cancer was 84% (95% confidence interval [CI], 80%-88%) and 88% (95% CI, 83%-92%) for clinical stage I disease resected within 1month of diagnosis. Video-assisted thoracoscopic surgery and sublobar resection increased significantly, from 10% to 34% (P<.0001) and 22% to 34% (P=.01) respectively; there were no significant differences in the percentage of malignant diagnoses (90% vs 87%, P=.36), clinical stage I (92% vs 89%, P=.33), pathologic stage I (85% vs 82%, P=.44), tumor size (P=.61), or cell type (P=.81). The frequency and extent of surgery for nonmalignant disease can be minimized in a CT screening program and provide a high cure rate for those diagnosed with lung cancer and undergoing surgical resection.

Investigation of Complement Activation Product C4d as a Diagnostic and Prognostic Biomarker for Lung Cancer

There is a medical need for diagnostic biomarkers in lung cancer. We evaluated the diagnostic performance of complement activation fragments. We assessed complement activation in four bronchial epithelial and seven lung cancer cell lines. C4d, a degradation product of complement activation, was determined in 90 primary lung tumors; bronchoalveolar lavage supernatants from patients with lung cancer (n = 50) and nonmalignant respiratory diseases (n = 22); and plasma samples from advanced (n = 50) and early lung cancer patients (n = 84) subjects with inflammatory lung diseases (n = 133), and asymptomatic individuals enrolled in a lung cancer computed tomography screening program (n = 190). Two-sided P values were calculated by Mann-Whitney U test. Lung cancer cells activated the classical complement pathway mediated by C1q binding that was inhibited by phosphomonoesters. Survival was decreased in patients with high C4d deposition in tumors (hazard ratio [HR] = 3.06; 95% confidence interval [CI] = 1.18 to 7.91). C4d levels were increased in bronchoalveolar lavage fluid from lung cancer patients compared with patients with nonmalignant respiratory diseases (0.61 ± 0.87 vs 0.16 ± 0.11 µg/mL; P < .001). C4d levels in plasma samples from lung cancer patients at both advanced and early stages were also increased compared with control subjects (4.13 ± 2.02 vs 1.86 ± 0.95 µg/mL, P < 0.001; 3.18 ± 3.20 vs 1.13 ± 0.69 µg/mL, P < .001, respectively). C4d plasma levels were associated with shorter survival in patients at advanced (HR = 1.59; 95% CI = 0.97 to 2.60) and early stages (HR = 5.57; 95% CI = 1.60 to 19.39). Plasma C4d levels were reduced after surgical removal of lung tumors (P < .001) and were associated with increased lung cancer risk in asymptomatic individuals with (n = 32) or without lung cancer (n = 158) (odds ratio = 4.38; 95% CI = 1.61 to 11.93). Complement fragment C4d may serve as a biomarker for early diagnosis and prognosis of lung cancer.

Clinical Statement on the Role of the Surgeon and Surgical Issues Relating to Computed Tomography Screening Programs for Lung Cancer

The National Lung Screening Trial (NLST) recently provided the first definitive evidence that screening for lung cancer with low-dose computed tomography (LDCT) decreases lung cancer mortality in certain high-risk groups [1]. Several surgical and nonsurgical organizations, including the National Comprehensive Cancer Network (NCCN), International Association for the Study of Lung Cancer (IASLC), American Association for Thoracic Surgery (AATS), American College of Chest Physicians (ACCP), American Thoracic Society (ATS), and American Society of Clinical Oncology (ASCO), have outlined guidelines on lung cancer computed tomography (CT) screening, which have been recently published or are currently in print with the aim of addressing the specifics of the CT screening process while identifying the ideal target population for lung cancer screening [2–4].

Finding needles in a haystack: annual low-dose computed tomography screening reduces lung cancer mortality in a high-risk group

Evaluation of: Aberle DR, Adams AM, Berg CD et al.; National Lung Screening Trial Research Team. Reduced lung-cancer mortality with low-dose computed tomographic screening. N. Engl. J. Med. 365(5), 395–409 (2011).Lung cancer is a global health issue. Compared with other common malignancies, the prognosis is poor as many patients present with advanced disease. The National Lung Screening Trial (NLST) aimed to identify and treat early lung cancers using annual low-dose computed tomography (CT) screening in a high-risk group. When compared with chest x-ray screening, low-dose CT screening reduced lung cancer mortality by 20%; the NLST is the first lung cancer screening trial to demonstrate such a mortality benefit. However, we must wait for cost–effectiveness data from the NLST, as well as the results of ongoing European studies comparing low-dose CT with observation alone, before firm conclusions can be drawn regarding the overall benefits of introducing a CT screening program to clinical practice.

HRCT Features of Small Peripheral Lung Carcinomas Detected in a Low-dose CT Screening Program

To define high-resolution computed tomography (HRCT) features of lung cancers detected by computed tomography (CT) screening according to histopathology and prognosis. Tumor size, CT value, morphology, and tumor volume doubling time (TVDT) were determined for 10 atypical adenomatous hyperplasias (AAH) and 50 lung cancers followed between 1996 and 1998 to 2007. For the 10 AAHs, the density less than -500 HU in all lesions (mean, -654 HU) and the size was up to 14 mm (mean, 9 mm); all patients remain alive. Focal bronchioloalveolar cell carcinomas (BAC) were denser (mean, -537 HU) than AAH and mostly less dense than -350 HU; all patients remain alive. All 22 adenocarcinomas (ADC) were denser than -450 HU (mean, -186 HU); 6 were problematic and measured >-150HU and >10 mm or had >10 mm of central denser zone (CDZ) (partly solid tumors) or tumor size (solid tumor). Two of four squamous cell carcinomas (SCC) measuring 15 and 10 mm, respectively, were problematic. Two patients with small-cell lung carcinomas (SCLC) measuring 15 and 23 mm, respectively, remain alive. AAH, BAC, ADC, and SCC lesions were in general polygonal in shape. SCLC lesions appeared as round nodules with excrescence. The mean TVDT for AAH, BAC, ADC, SCC, and SCLC was 1278, 557, 466, 212, and 103 days, respectively. The CT features reflected tumor aggressiveness. Non-SCLC lesions of >-150HU and >10 mm (or >-100HU and >10 mm for the solid portion of the tumor) are associated with unfavorable prognosis. Timely interventions should be undertaken before problematic increase in number of cases.

Developing an Effective Lung Cancer Program in a Community Hospital Setting

Lung cancer remains the largest source of cancer-based mortality in men and women. Although there are several highly acclaimed centers in the treatment of patients with lung cancer nationally, the vast majority of lung cancer care occurs in community hospital settings. The importance of proper lung cancer care in the community hospital setting cannot be overemphasized. We have had the opportunity to develop several highly successful community hospital—based lung cancer programs over the past several years. Using a multidisciplinary approach to the treatment of patients with lung cancer, we have been able to achieve survival results better than all state and national averages stage for stage, in some cases doubling national survival rates. Key components of a successful program include holding a weekly multidisciplinary lung cancer tumor board meeting with representatives from medical oncology, thoracic surgery, pulmonary medicine, radiology, radiation oncology, and nuclear medicine to discuss patient presentation, test results, treatment history, and plans for therapy. A dedicated thoracic surgeon committed to the program is essential. A surgeon skilled in video-assisted thoracic surgery procedures, in particular minimally invasive lobectomy, is an added bonus and demonstrates a dedication to modern technology and improved patient care. A nurse navigator is used to help patients through the process from detection to recovery and provide a personal bond that greatly improves patient satisfaction. Treatment guidelines provide continuity and guidance and a starting point for a group to develop specialized treatment strategies. Physician education by personal office visits or continuing medical education—style talks helps the medical doctors in the community know what you are doing. We offer doctors the opportunity to have their patients presented at the weekly meetings for numerous free second opinions. All patients are seen within 24 hours of referral, and all patients are sent back to the primary medical doctor, who is kept in the loop at all times. A computed tomography screening program (low cost if possible) adds to our program despite the controversy in the journals and press. Numerous early cancers have been detected and treated as a result of this program. A dedicated cancer center shows a commitment to cancer care and allows for many services to be offered at a single location, thereby greatly improving convenience for the patient and interaction among the physicians. Access to research protocols is essential to provide the most up-to-date care and offer the patients in your community the opportunity to be treated similar to that provided at major centers across the country. To summarize, several simple steps help to provide a quality lung cancer program in a community hospital setting, resulting in improved outcomes.

Mean sojourn time and effectiveness of mortality reduction for lung cancer screening with computed tomography

This study aimed to estimate the mean sojourn time (MST) and sensitivity of asymptomatic lung cancer (ALC) detected by computed tomography (CT) or chest X-ray (CXR). Translation of early diagnosis into mortality reduction by 2 detection modalities and inter-screening interval was projected using a Markov model. On the basis of systematic literature review, data from 6 prospective CT screening studies were retrieved. The MST in association with the natural history of lung cancer depicted by a 3-state Markov model was estimated with a Bayesian approach. To project mortality reduction attributed to screening, the model was further extended to 5 health states for the inclusion of prognostic part. The analysis was run with a 10-year time horizon of follow-up, mimicking the Dutch-Belgian randomized lung cancer screening trial (NELSON). Screening for lung cancer with CT had high sensitivity (median: 97%) and may advance 1 year earlier than CXR in detecting ALC. By simulating the scenario similar to NELSON study, CT screen may gain an extra of 0.019 year of life expectancy per person, yields 15% mortality reduction (relative risk (RR): 0.85, 95% confidence interval [95%CI: (0.58-1.01)]. Approximate 23% [RR: 0.77, 95%CI: (0.43-0.98)] mortality reduction would be achieved by annual CT screening program. The mortality findings in conjunction with higher sensitivity and shorter MST estimate given data on prevalent and incident (2nd) screen may provide a tentative evidence, suggesting that annual CT screening may be required in order to be effective in reducing mortality before the results of randomized controlled studies available.

Stage distribution in patients with a small (< or = 3 cm) primary nonsmall cell lung carcinoma. Implication for lung carcinoma screening.

Recently, there has been increased interest in the use of computed tomography (CT) for lung carcinoma screening. For this technique to be effective, small tumors must be detected at an earlier stage than large lesions. However, to the authors's knowledge, the relationship between the size of small primary (< or = 3 cm) neoplasms and disease stage at presentation has never been established clearly. The current study was performed to determine whether smaller lesions indeed have an earlier stage distribution compared with larger tumors. The Duke University Medical Center Tumor Registry identified 620 patients (261 women and 359 men, with a mean age of 67 years) who presented with pathologically proven primary nonsmall cell lung carcinomas measuring < or = 3 cm between 1980-1999. Surgical, pathologic, and imaging information was reviewed retrospectively to confirm the size of the lesion and the disease stage at the time of presentation. The distribution of tumor size within each stage and the distribution of disease stage according to tumor size were determined. Tumors occurring in patients with TNM Stage IIIB disease were slightly larger than those found in patients with either more advanced or less advanced disease. However, there was no apparent statistically significant relation between the stage distribution and the size of the primary lesion. The current study data did not find a statistically significant relation between the size of small primary lung tumors and the distribution of disease stage at the time of presentation. This finding suggests that the detection of small tumors using screening CT may not result in a shift to an earlier disease stage distribution. A reduction in mortality needs to be demonstrated by appropriate clinical trials prior to the initiation of mass CT screening programs.