RT Journal Article
SR Electronic
T1 Final screening round of the NELSON lung cancer screening trial: the effect of a 2.5-year screening interval
JF Thorax
JO Thorax
FD BMJ Publishing Group Ltd and British Thoracic Society
SP 48
OP 56
DO 10.1136/thoraxjnl-2016-208655
VO 72
IS 1
A1 Uraujh Yousaf-Khan
A1 Carlijn van der Aalst
A1 Pim A de Jong
A1 Marjolein Heuvelmans
A1 Ernst Scholten
A1 Jan-Willem Lammers
A1 Peter van Ooijen
A1 Kristiaan Nackaerts
A1 Carla Weenink
A1 Harry Groen
A1 Rozemarijn Vliegenthart
A1 Kevin ten Haaf
A1 Matthijs Oudkerk
A1 Harry de Koning
YR 2017
UL http://thorax.bmj.com/content/72/1/48.abstract
AB Background In the USA annual lung cancer screening is recommended. However, the optimal screening strategy (eg, screening interval, screening rounds) is unknown. This study provides results of the fourth screening round after a 2.5-year interval in the Dutch-Belgian Lung Cancer Screening trial (NELSON).Methods Europe's largest, sufficiently powered randomised lung cancer screening trial was designed to determine whether low-dose CT screening reduces lung cancer mortality by ≥25% compared with no screening after 10 years of follow-up. The screening arm (n=7915) received screening at baseline, after 1 year, 2 years and 2.5 years. Performance of the NELSON screening strategy in the final fourth round was evaluated. Comparisons were made between lung cancers detected in the first three rounds, in the final round and during the 2.5-year interval.Results In round 4, 46 cancers were screen-detected and there were 28 interval cancers between the third and fourth screenings. Compared with the second round screening (1-year interval), in round 4 a higher proportion of stage IIIb/IV cancers (17.3% vs 6.8%, p=0.02) and higher proportions of squamous-cell, bronchoalveolar and small-cell carcinomas (p=0.001) were detected. Compared with a 2-year interval, the 2.5-year interval showed a higher non-significant stage distribution (stage IIIb/IV 17.3% vs 5.2%, p=0.10). Additionally, more interval cancers manifested in the 2.5-year interval than in the intervals of previous rounds (28 vs 5 and 28 vs 19).Conclusions A 2.5-year interval reduced the effect of screening: the interval cancer rate was higher compared with the 1-year and 2-year intervals, and proportion of advanced disease stage in the final round was higher compared with the previous rounds.Trial registration number ISRCTN63545820.