2026-03-31 ブラウン大学
＜関連情報＞
- https://www.brown.edu/news/2026-03-31/lung-cancer-scans
- https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2847140
- https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2804380
国立肺がんスクリーニング試験における重要な偶発的所見と肺外がんの診断 Significant Incidental Findings in the National Lung Screening Trial and Diagnosis of Extrapulmonary Cancer
Ilana F. Gareen, PhD; Roee Gutman, PhD; Maryanne Thangarajah, MS;et al
JAMA Network Open Published:March 31, 2026
DOI:10.1001/jamanetworkopen.2026.3398
Key Points
Question What was the association between significant incidental findings (SIFs) detected on low-dose computed tomography screening examinations in the National Lung Screening Trial and extrapulmonary cancer diagnoses?
Findings In this cohort study of 26 445 participants, those in whom a cancer-associated SIF was detected had a higher risk of cancer diagnosis in the year following the screening examination than participants with no cancer-associated SIF.
Meaning These findings suggest that certain SIFs should be evaluated as potential indicators of undiagnosed cancers.
Abstract
Importance Significant incidental findings (SIFs) not related to lung cancer have been widely reported in patients undergoing lung cancer screening with low-dose computed tomography (LDCT). It is unclear whether SIFs are associated with extrapulmonary cancer diagnoses.
Objective To examine the association between an SIF considered to be potentially indicative of extrapulmonary cancer (cancer SIF) detected at LDCT lung cancer screening and diagnosis of an extrapulmonary cancer within 1 year of the screen.
Design, Setting, and Participants This retrospective cohort study analyzed data from National Lung Screening Trial (NLST) participants. The NLST participants were randomly assigned to either LDCT or chest radiography to determine whether LDCT was associated with a reduction in lung cancer mortality compared with chest radiography alone. Participants aged 55 to 74 years were recruited between August 2002 and April 2004. They received up to 3 rounds of screening and were followed up for 5 to 7 years. The study concluded December 31, 2009. This analysis was restricted to participants in the LDCT arm and was conducted between June and December 2025.
Exposure Detection of a cancer SIF (ie, SIF potentially indicative of a cancer) at any lung cancer screening round in the NLST.
Main Outcomes and Measures The primary outcome was diagnosis of an extrapulmonary cancer within 1 year of a screening round. Extrapulmonary cancers were classified using Surveillance, Epidemiology, and End Results (SEER) Program organ system categories. Cancer SIFs were mapped to specific SEER cancer categories. Multilevel logistic regression was used to assess the association between detection of a cancer SIF and diagnosis of an extrapulmonary cancer.
Results The study included 75 104 LDCT screening rounds performed in 26 445 participants (mean [SD] age, 61.4 [5.0] years; 59.0% male). Cancer SIFs were reported for 2265 screening rounds (3.0%) in 1807 participants (6.8%) across the 3 screening rounds. An extrapulmonary cancer was diagnosed following a screening round with a cancer SIF (n = 2265) for 67 participants (3.0%). The marginal risk difference, after covariates and participant-specific adjustments, was 13.89 (95% confidence limit [CL], 7.03-20.75) per 1000 participants. The marginal risk differences were significantly higher for urinary cancers (17.03 [95% CL, 8.55-25.50] per 1000 participants) and other SEER cancer categories, including lymphoma and leukemia (13.83 [95% CL, 3.46-24.21] per 1000 participants).
Conclusions and Relevance This cohort study found that cancer SIFs were associated with an increased risk of an extrapulmonary cancer diagnosis in the year following an LDCT lung cancer screening examination. These findings suggest that certain SIFs should be evaluated as potential indicators of undiagnosed cancers.
全米肺がんスクリーニング試験における重要な偶発的所見 Significant Incidental Findings in the National Lung Screening Trial
Ilana F. Gareen, PhD; Roee Gutman, PhD; JoRean Sicks, MS;et al
JAMA Internal Medicine Published:May 8, 2023
DOI:10.1001/jamainternmed.2023.1116
Key Points
Question What were the types of significant incidental findings (SIFs) detected on low-dose computed tomography screening examinations in the National Lung Screening Trial?
Findings In this case series study of 26 455 participants who underwent screening with low-dose computed tomography in the National Lung Screening Trial, 8954 (33.8%) had a SIF reported. Most screening tests with a SIF (12 228 [89.1%]) had at least 1 abnormality considered reportable to the referring clinician; the most common SIFs included emphysema (8677 of 20 156 [43.0%]), coronary artery calcium (2432 [12.1%]), and masses (1493 [7.4%]).
Meaning The results of this case series study suggest that SIFs should be reported in a consistent manner and that SIF management should follow established guidelines to potentially minimize costs to patients, clinicians, and the health care system.
Abstract
Importance Low-dose computed tomography (LDCT) lung screening has been shown to reduce lung cancer mortality. Significant incidental findings (SIFs) have been widely reported in patients undergoing LDCT lung screening. However, the exact nature of these SIF findings has not been described.
Objective To describe SIFs reported in the LDCT arm of the National Lung Screening Trial and classify SIFs as reportable or not reportable to the referring clinician (RC) using the American College of Radiology’s white papers on incidental findings.
Design, Setting, and Participants This was a retrospective case series study of 26 455 participants in the National Lung Screening Trial who underwent at least 1 screening examination with LDCT. The trial was conducted from 2002 to 2009, and data were collected at 33 US academic medical centers.
Main Outcomes and Measures Significant incident findings were defined as a final diagnosis of a negative screen result with significant abnormalities that were not suspicious for lung cancer or a positive screen result with emphysema, significant cardiovascular abnormality, or significant abnormality above or below the diaphragm.
Results Of 26 455 participants, 10 833 (41.0%) were women, the mean (SD) age was 61.4 (5.0) years, and there were 1179 (4.5%) Black, 470 (1.8%) Hispanic/Latino, and 24 123 (91.2%) White individuals. Participants were scheduled to undergo 3 screenings during the course of the trial; the present study included 75 126 LDCT screening examinations performed for 26 455 participants. A SIF was reported for 8954 (33.8%) of 26 455 participants who were screened with LDCT. Of screening tests with a SIF detected, 12 228 (89.1%) had a SIF considered reportable to the RC, with a higher proportion of reportable SIFs among those with a positive screen result for lung cancer (7632 [94.1%]) compared with those with a negative screen result (4596 [81.8%]). The most common SIFs reported included emphysema (8677 [43.0%] of 20 156 SIFs reported), coronary artery calcium (2432 [12.1%]), and masses or suspicious lesions (1493 [7.4%]). Masses included kidney (647 [3.2%]), liver (420 [2.1%]), adrenal (265 [1.3%]), and breast (161 [0.8%]) abnormalities. Classification was based on free-text comments; 2205 of 13 299 comments (16.6%) could not be classified. The hierarchical reporting of final diagnosis in NLST may have been associated with an overestimate of severe emphysema in participants with a positive screen result for lung cancer.
Conclusions and Relevance This case series study found that SIFs were commonly reported in the LDCT arm of the National Lung Screening Trial, and most of these SIFs were considered reportable to the RC and likely to require follow-up. Future screening trials should standardize SIF reporting.
