Results from the Early Diagnosis of Lung Cancer Scotland (ECLS) study suggest that the EarlyCDT-Lung test can identify individuals at high risk of lung cancer.
The ECLS study randomly assigned 12,208 people at risk of developing lung cancer in Scotland. The intervention arm received the EarlyCDT-Lung test, which measures seven autoantibodies (AABs). If the EarlyCDT-Lung test was positive, participants received low-dose computed tomography (LDCT) scanning six-monthly for up to two years. EarlyCDT-Lung test negative and control arm participants received standard clinical care.
At two years post-randomisation, 127 lung cancers were detected in the study population (1.0%).
In the intervention arm, 33 of 56 (58.9%) lung cancers were diagnosed at stage III/IV compared with 52 of 71 (73.2%) in the control arm. The hazard ratio for stage III/IV presentation was 0.64 (95% CI, 0.41-0.99). However, the authors say the diagnosis rate was lower than anticipated when planning the study and lower than might be expected from other studies using LDCT, suggesting the approach (vs LDCT) may have missed early-stage lung cancers.
There were non-significant differences in lung cancer and all-cause mortality after two years.
The seven AABs of the EarlyCDT-Lung test demonstrated high specificity (90.3%) but moderate sensitivity (32.1%) for detecting lung cancer at two years.
The study was not designed to assess the incremental contribution of the EarlyCDT-Lung test, however, the authors say “the observation of a stage-shift towards earlier-stage lung cancer diagnosis merits further investigations to evaluate whether the EarlyCDT-Lung test adds anything to the emerging standard of LDCT.”
They stress that even with a lower rate of lung cancer, those in the intervention arm were at a statistically significant and clinically important reduced risk of stage III/IV presentation.
The findings are published in the European Respiratory Journal.
