Incidentally Detected Adrenal Nodules on Lung Cancer Screening CT.

Objective: To assess adherence to ACR recommendations for managing incidental adrenal lesions detected on lung cancer screening (LCS) CT examinations.

Methods: We performed a retrospective analysis of all LCS CT examinations within our health care system from January 2015 to August 2023. We included CTs that were reported with Lung-RADS "S" modifier for a focal adrenal lesion. We recorded whether follow-up imaging and biochemical testing were recommended and whether they were performed. Follow-up recommendations in reports were assessed for adherence to ACR recommendations.

Results: During the study period, 191 patients had a focal adrenal nodule reported. Per ACR recommendations, 36 of 191 (19%) warranted follow-up, but only 23 of 36 (64%) of these received follow-up recommendations. Of those 191, 155 (81%) did not require follow-up per ACR, and 25 of those 155 (16%) received follow-up recommendations. Of those who were advised follow-up, 34 of 48 (71%) received dedicated follow-up, 9 of 48 (19%) received follow-up imaging for another reason, and 5 of 48 (10%) did not receive any follow-up. Among those in whom follow-up was not recommended, 21 of 143 (15%) received dedicated follow-up, 101 of 143 (71%) received follow-up imaging for another reason, and 21 of 143 (15%) did not receive any follow-up. No malignant lesions were diagnosed. Per ACR recommendations, 183 of 191 (96%) of patients should have received biochemical testing; however, it was recommended in only 4 patients (2%).

Discussion: There was suboptimal adherence to ACR recommendations for managing incidental adrenal lesions on LCS CTs, with both unnecessary and missing follow-up recommendations. Recommendations for biochemical testing were nearly nonexistent, despite being part of the ACR algorithm.