What is the psychological impact of lung cancer screening using a novel antibody blood test?
Problem
Lung cancer screening can reduce lung cancer mortality by 20% and is currently recommended in the USA, but not the UK. Ensuring any potential psychological harm is minimised is important. Current evidence is limited to the psychological impact of CT lung cancer screening. This study assesses psychological responses to screening using a novel tumour antibody blood test (Early CDT®-Lung test) within The Early Cancer Detection Test - Lung Cancer Scotland Study (ECLS) to aid the early detection of lung cancer.
Approach
ECLS study participants (n=12,208) were randomised to an Early CDT®-Lung test group or a control group. Test-positive participants also had CT scans 6-monthly for 2 years. A sample (n=1,032) of test-positive and test-negative participants completed questionnaires measuring psychological responses (positive and negative affect schedule, lung cancer worry scale and impact of events scale (IES)) at baseline and 1, 3, 6 and 12 months post-trial recruitment. Random effects linear and logistic regression compared psychological responses over time between controls, test-positive and test-negative participants.
Findings
Compared to controls, test-positive participants were significantly more likely to worry about developing lung cancer at 1 month (OR: 3.30 [95%CI: 1.73, 6.34]).Compared to controls, test-negative participants had significantly higher levels of positive affect at 1, 3 and 6 months (difference between means (DBM): 1.45 [0.44, 2.47], 1.46 [0.42, 2.49], 1.35 [0.32, 2.38] respectively) and at 3 months were significantly less likely to worry about developing lung cancer (OR: 0.53 [0.30, 0.93]), reported lower impact of worries (DBM -0.26 [-0.45, -.07]), and lower levels of negative affect (DBM -1.46 [-2.57, -0.35]). Compared to test-positive participants, test-negative participants were significantly less likely to worry about developing lung cancer at 1, 3 and 6 months (OR: 0.42 [0.24, 0.74], 0.43 [0.25, 0.76], 0.36 [0.20, 0.64] respectively) or be anxious about future treatment at 1 and 3 months (OR: 0.19, [0.09, 0.37], 0.49 [0.25, 0.99] respectively). Test-negative participants also reported significantly lower impact of lung cancer worry at 1 and 3 months (DBM -0.26 [-0.45, -0.06], -0.29 [-0.49, -0.09] respectively), higher positive affect at 3 months (DBM 1.58 [0.50, 2.67]), and lower IES scores at 1 month (avoidance DBM: -2.04 [-2.80, -1.27], intrusion DBM: -1.54 [-2.14, -0.95]), 3 months (avoidance DBM: -1.18 [-1.95, -0.41], intrusion DBM: -1.07 [-1.67, -0.48]) and 6 months (avoidance DBM: -1.17 [-1.94, -0.40], intrusion DBM: -0.76 [-1.36, -0.16]). No significant differences between groups were evident at 12 months.
Consequences
Findings suggest lung cancer screening may initially increase worries in those with a positive test and reduce worries and distress in those with a negative test. However, most differences were short-lived and small and may not be clinically important. Lung cancer screening using the Early CDT®-Lung test does not appear to have a long term negative psychological impact.