Autoantibody blood test improves lung cancer detection
BARCELONA — Use of the EarlyCDT-Lung test in combination with chest X-ray and CT imaging led to the detection of lung cancer at an earlier, more treatable stage, according to results of a randomized trial conducted in Scotland and presented during the presidential symposium of International Association for the Study of Lung Cancer World Conference on Lung Cancer.
EarlyCDT-Lung (Oncimmune) is an autoantibody diagnosis test that stratifies individuals according to their risk for developing lung cancer based on the presence of seven antigens, p53, NY-ESO-1, CAGE, GBU4-5, SOX2, HuD and MAGE-A4. Data have shown that the test identifies 41% of lung cancers with 90% specificity, whereas CT scanning identifies 67% of lung cancers with 49% specificity.
Frank Sullivan, FRSE, FRCP, FRCGP, professor of primary care medicine and medical school director of research at University of St. Andrews in the United Kingdom, and colleagues evaluated whether the use of EarlyCDT-Lung followed by chest X-ray and CT scanning would identify individuals at high risk for lung cancer and reduce the incidence of late-stage lung cancer or unclassified presentation at diagnosis.
“The people we were targeting were asymptomatic,” Sullivan said during a press conference. “We went to the practices themselves in the most deprived areas of Scotland and searched through the records to find patients who had more than 20 pack-years of smoking history or a first-degree family history of lung cancer. They also had to be fit enough for surgery with an ECOG performance score of 0 to 2.”
The analysis included 12,209 patients aged 50 to 75 years at high risk for lung cancer who were randomly assigned the study intervention (n = 6,088) or standard of care in Scotland (n = 6,121).
Patients in the intervention group who tested positive with EarlyCDT-Lung underwent an immediate chest X-ray and CT scan with follow-up every 6 months for 2 years. Patients with negative results underwent standard care.
The difference between the number of patients with stage III, stage IV or unclassified lung cancer at diagnosis served as the study’s primary endpoint.
Overall, 127 patients received a lung cancer diagnosis during the study period, which included 56 patients in the intervention group and 71 in the control group. In total, 9.8% of those in the intervention group tested positive on EarlyCDT-Lung, and 3.4% (n = 18) were diagnosed with lung cancer during the study.
Significantly fewer patients in the intervention group received a late-stage or unclassified diagnosis at 2 years after randomization compared with the control group (58.9% vs. 73.2%). These data suggested a 90.4% specificity at 2-year follow-up, with 32.7% sensitivity for all lung cancer detection and 52.2% for early lung cancer detection.
At 2 years, lung cancer mortality appeared reduced in the intervention arm (HR = 0.64; 95% CI, 0.41-0.99), but Sullivan noted that the study was not adequately powered to assess mortality.
“The 36% reduction in late-stage presentation after 2 years of follow-up among those randomly assigned to the intervention seems worthwhile, both clinically and statistically,” Sullivan said. “Because this is a relatively straightforward blood test, we were able to capture data from most patients in these deprived areas with very high follow-up using registry data.”
The full value of the test will depend on larger studies underway, Sullivan added. – by Alexandra Todak
Sullivan F, et al. Abstract PL02.03. Presented at: International Association for the Study of Lung Cancer World Conference on Lung Cancer; Sept 7-10, 2019; Barcelona.
Disclosures: Sullivan reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.