Management of patients with adrenal myelolipoma: experience from a tertiary referral centre.

Background: Adrenal myelolipomas are rare, benign, tumours of the adrenal cortex.

Aims: This study reports the experience of a tertiary adrenal surgery referral centre's approach to the management of patients with adrenal myelolipoma.

Methods: A retrospective observational cohort study was conducted on all adult patients (> 18 years age) diagnosed with adrenal myelolipoma from January 1, 2014, to December 30, 2022. Demographics, imaging characteristics, histological diagnosis (where applicable) and follow-up data were compared between patients undergoing surgery and those referred to surveillance. Indications for operative intervention were recorded at the time of multidisciplinary team discussion, consisting of surgeons, endocrinology physicians, radiologists, pathologists and specialist nursing representatives.

Results: Of the 522 patients with an adrenal lesion discussed in adrenal tumour meeting between 2014 and 2022, n = 15 (2.8%) were diagnosed with adrenal myelolipoma. Of the 15 patients, 4 underwent adrenalectomy at first presentation (27%), while 1 patient underwent adrenalectomy after interval follow-up. Indications for operative intervention were as follows: 'indeterminate lesion' (n = 3), 'abdominal pain and size (> 4 cm)' (n = 1) and 'mass effect on adjacent organs' (n = 1). The mean rate of lesion growth in patients referred for surveillance (n = 10) was 0.13 cm/year. Histology confirmed adrenal myelolipoma as the diagnosis in all resected tumours.

Conclusions: For patients with adrenal myelolipoma, the presence of symptoms and/or indeterminate features on imaging may be more clinically useful indications for operative intervention over size alone. The surveillance of adrenal myelolipomas, even in patients with adrenal lesions > 4 cm, is a safe clinical strategy, provided the imaging characteristics are benign and patients remain asymptomatic.