Clinical Course of Adrenal Myelolipoma

A Long-Term Longitudinal Follow-up Study

Oksana Hamidi; Ram Raman; Natalia Lazik; Nicole Iniguez-Ariza; Travis J. McKenzie; Melanie L. Lyden; Geoffrey B. Thompson; Benzon M. Dy; William F. Young Jr; Irina Bancos


Clin Endocrinol. 2020;93(1):11-18. 

In This Article

Subjects and Methods


We performed a retrospective longitudinal follow-up study of consecutive patients with adrenal myelolipoma evaluated at Mayo Clinic between 1 January 2000 and 31 December 2016. The study was approved by the Mayo Clinic Institutional Review Board. The Mayo Clinic Adrenal Tumor database was reviewed to identify all patients with myelolipoma. The diagnosis was based on computerized tomography (CT), magnetic resonance imaging (MRI) and/or post-operative histopathology of the tumour. Definition of myelolipoma by CT was based on the characteristic appearance of a well-circumscribed nonhomogeneous macroscopic fat-containing adrenal mass with low attenuation on unenhanced imaging and no enhancement with contrast medium. Definition of myelolipoma by MRI was based on a high signal intensity on T1-weighted images due to macroscopic fat content, confirmed by demonstrating a loss of signal intensity within the fatty component on the out-of-phase images. All electronic medical records were reviewed for confirmation of diagnosis, radiologic and biochemical evaluation, management and follow-up.

Data Analysis

Descriptive statistics were used to provide a summary of the data. Categorical data were reported as absolute and relative frequencies (percentages). Continuous data were presented as median (minimum to maximum range). To compare medians between two independent groups, we used the nonparametric Wilcoxon rank-sum test. Logistic regression models were used to estimate association of factors of tumour size, tumour growth, and need for surgical resection. All tests were two-sided, and P values < .05 were considered statistically significant. All statistical analyses were conducted using JMP version 13 (SAS Institute).