Automated extraction of incidental adrenal nodules from electronic health records

Many adrenal incidentalomas do not undergo appropriate biochemical testing and complete imaging characterization to assess for hormone hypersecretion and malignancy. With the growing availability of clinical narratives in the electronic medical record, automated surveillance using advanced data analytic techniques may represent a promising method to improve management.

A data provisioning process using a series of structured query language scripts was used to abstract all chest and abdominal computed tomography and magnetic resonance imaging reports from an academic health care system in 2018. The narratives and impressions were queried for key text relating to the identification of adrenal incidentalomas. Patients with a history of extra-adrenal malignancy undergoing staging or surveillance imaging were excluded. The prevalence and radiographic characteristics were analyzed. Patients with adrenal incidentalomas newly identified in 2018 were assessed for biochemical testing and nodule stability through August 2021.

Of 36,618 patients queried, 8,557 were excluded owing to a history of extra-adrenal malignancy. Data from 447 patients were flagged by the structured query language scripts and electronically abstracted. On internal validation, 307/447 (69%) patients were correctly identified as having adrenal nodules (1.1% overall prevalence). The median patient age was 67 years, and 56% were female. The median nodule size was 1.7 (IQR 1.3-2.5) cm, 9% were bilateral, and 63% were low density (unenhanced Hounsfield units <10). Adrenal carcinoma was identified in 10 patients. In 2018, 121 patients were diagnosed with a new adrenal incidentaloma. Of 32 (27%) patients who had follow-up imaging at a median of 1.9 years, 97% of nodules were stable in size. Biochemical testing was performed in 53 patients (44%), of which 31 (26%) had complete hormonal assessment; 14 (26%) were functional nodules: 7 aldosterone-secreting, 4 cortisol-secreting, and 3 pheochromocytoma.

Only one-fourth of patients received appropriate biochemical testing after incidental diagnosis of an adrenal nodule, and most nodules with indeterminate imaging characteristics did not undergo follow-up imaging. Advanced data analytic techniques on electronic imaging reports may aid in the clinical identification and improved management of patients with adrenal incidentalomas.