Presentation and clinical patterns of bilateral adrenal lesions: a retrospective cohort study.

Abstract

The clinical relevance of etiologic concordance and temporal presentation in bilateral adrenal masses remains poorly defined, creating uncertainty in diagnostic evaluation and management. To characterize the etiologic spectrum of bilateral adrenal masses, evaluate patterns by concordance and synchronicity, and identify predictors of discordance and malignant or pheochromocytoma contralateral lesions. Retrospective cohort study (2010-2025). Tertiary referral center. Adults with bilateral adrenal masses. Etiology, concordance, synchronicity, interval to contralateral lesion, and factors associated with discordance and malignant or pheochromocytoma contralateral lesions. Among 1035 patients (median age 59.6 years; 51% women), 85% had concordant and 15% discordant etiologies. Concordant cases were predominantly bilateral benign cortical lesions (76%), whereas discordant cases were heterogeneous (benign 35%, malignant 31%, and indeterminate 34%). Presentation was synchronous in 84% and asynchronous in 16%, with a median interval of 45 months (interquartile range 15-87). Asynchronous disease was associated with higher discordance (23% vs 13%, P = .001) and greater prevalence of malignant lesions (bilateral malignant: 17% vs 7%; discordant malignant: 8% vs 4%; overall P < .001). Among asynchronous cases, shorter interval to contralateral lesion (<2 vs ≥5 years) was independently associated with malignant or pheochromocytoma etiology (adjusted odds ratio [OR] 2.63, 95% CI 1.01-6.85), as was larger tumor size (adjusted OR 1.06 per mm, 95% CI 1.02-1.09). Most bilateral adrenal masses are benign and concordant; however, discordant or asynchronous disease identifies a higher-risk subgroup enriched for malignancy. Early contralateral lesion development and larger tumor size are key risk factors.