Results of the Randomized Danish Lung Cancer Screening Trial with Focus on High-Risk Profiling.
BACKGROUND
As of April 2015, participants in the Danish Lung Cancer Screening Trial had been followed for at least 5 years since their last screening.


OBJECTIVE
Mortality, causes of death, and lung cancer findings are reported to explore the effect of computed tomography (CT) screening.


METHODS
A total of 4,104 participants aged 50-70 years at the time of inclusion and with a minimum 20 pack-years of smoking were randomized to have five annual low-dose CT scans (study group) or no screening (control group).


RESULTS
Follow-up information regarding date and cause of death, lung cancer diagnosis, cancer stage, and histology was obtained from national registries. No differences between the two groups in lung cancer mortality (hazard ratio, 1.03; 95% confidence interval, 0.66-1.6; P = 0.888) or all-cause mortality (hazard ratio, 1.02; 95% confidence interval, 0.82-1.27; P = 0.867) were observed. More cancers were found in the screening group than in the no-screening group (100 vs. 53, respectively; P < 0.001), particularly adenocarcinomas (58 vs. 18, respectively; P < 0.001). More early-stage cancers (stages I and II, 54 vs. 10, respectively; P < 0.001) and stage IIIa cancers (15 vs. 3, respectively; P = 0.009) were found in the screening group than in the control group. Stage IV cancers were nonsignificantly more frequent in the control group than in the screening group (32 vs. 23, respectively; P = 0.278). For the highest-stage cancers (T4N3M1, 21 vs. 8, respectively; P = 0.025), this difference was statistically significant, indicating an absolute stage shift. Older participants, those with chronic obstructive pulmonary disease, and those with more than 35 pack-years of smoking had a significantly increased risk of death due to lung cancer, with nonsignificantly fewer deaths in the screening group.


CONCLUSIONS
No statistically significant effects of CT screening on lung cancer mortality were found, but the results of post hoc high-risk subgroup analyses showed nonsignificant trends that seem to be in good agreement with the results of the National Lung Screening Trial. Clinical trial registered with www.clinicaltrials.gov (NCT00496977).
1 Department of Respiratory Medicine and.|2 Department of Imaging, Nordsjællands Hospital, Hillerød, Denmark.
Mathilde M W
MM
Wille
1 Department of Respiratory Medicine and.
Asger
A
Dirksen
1 Department of Respiratory Medicine and.|3 Department of Radiology, Akershus University Hospital, Lørenskog, Norway.
Haseem
H
Ashraf
4 Department of Respiratory Medicine and.
Zaigham
Z
Saghir
5 Department of Radiology, Gentofte University Hospital, University of Copenhagen, Hellerup, Denmark.
Karen S
KS
Bach
6 Research Unit for General Practice, Faculty of Health Science, University of Copenhagen, Copenhagen, Denmark.
John
J
Brodersen
1 Department of Respiratory Medicine and.|7 Center for Clinical Education.
Paul F
PF
Clementsen
8 Department of Radiology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark.
Hanne
H
Hansen
4 Department of Respiratory Medicine and.
Klaus R
KR
Larsen
9 Department of Clinical Physiology, Nuclear Medicine and PET, and.
Jann
J
Mortensen
6 Research Unit for General Practice, Faculty of Health Science, University of Copenhagen, Copenhagen, Denmark.
Jakob F
JF
Rasmussen
1 Department of Respiratory Medicine and.
Niels
N
Seersholm
10 Department of Pathology, Rigshospitalet and Bispebjerg Hospital, Copenhagen, Denmark; and.
Birgit G
BG
Skov
1 Department of Respiratory Medicine and.
Laura H
LH
Thomsen
11 Danish Center for Sleep Medicine, Glostrup Hospital, Glostrup, Denmark.
Philip
P
Tønnesen
12 Department of Thoracic Surgery, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
Jesper H
JH
Pedersen
D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D015897:Comorbidity; D003718:Denmark / Q000453:epidemiology; D055088:Early Detection of Cancer; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology; D018570:Risk Assessment; D055752:Small Cell Lung Carcinoma / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D012907:Smoking; D014057:Tomography, X-Ray Computed
chronic obstructive pulmonary disease; computed tomography; lung cancer; screening