CT screening for lung cancer: Frequency of enlarged adrenal glands identified in baseline and annual repeat rounds.

Abstract

To determine the frequency of adrenal enlargement of participants in a CT-screening program for lung cancer and demonstrate the progression during follow-up, separately for baseline and annual repeat rounds. HIPAA-compliant informed consent was obtained in 4,776 participants. The adrenal gland was defined as enlarged if it measured ≥6mm at its largest diameter. Logistic regression analyses were performed. At baseline, 202 (4%) of 4,776 participants had adrenal enlargement. Significant factors were age (OR = 1.4, 95% CI: 1.2-1.7) and current smoker (OR = 1.8, 95% CI: 1.3-2.4). Follow-up 7-18months after baseline for 133 cases with adrenal enlargement <40mm showed it decreased or was stable in 85 (64%), and increased by <10mm in 48 (36%). Five (0.04%) cases of adrenal enlargement were newly identified, none increased beyond 40mm on follow-up. Adrenal enlargement was a significant predictor of a subsequent diagnosis of lung cancer (OR = 2.0, 95% CI: 1.2-3.4). Participants with adrenal enlargement <40mm identified at baseline and on repeat screening could be reasonably assessed on subsequent annual screening. Adrenal enlargement increased with increasing pack-years of smoking. Adrenal enlargement was an independent predictor of a subsequent diagnosis of lung cancer. • Adrenal enlargement was seen in 4% of participants at baseline screening. • Age and currently smoking were significantly associated with adrenal enlargement. • 0.04% of participants were newly identified with adrenal enlargement. • Annual follow-up for adrenal enlargement <40mm was appropriate. • Adrenal enlargement was an independent predictor of a diagnosis of lung cancer.