Adrenal Myelolipoma Presenting as a Retroperitoneal Mass: A Case Report

Introduction: Adrenal myelolipoma is a rare, benign, non-functional adrenal tumor composed of mature adipose tissue and trilineage hematopoietic elements. Most cases are asymptomatic and detected incidentally during imaging for unrelated conditions. Large lesions may present with compressive symptoms or complications such as hemorrhage or rupture. The exact pathogenesis remains unclear but is hypothesized to involve metaplasia of adrenal cortical cells due to chronic stress or endocrine stimulation. Case Presentation: A 54-year-old male with type 2 diabetes mellitus and hypertension presented with a one-year history of decreased urine stream. Imaging revealed a large, non-enhancing, fat-density mass in the right adrenal gland measuring 10.4 × 6.4 × 6.0 cm, abutting the liver and inferior vena cava. Hormonal evaluation was normal. The patient underwent right open adrenalectomy. Gross examination showed a well-encapsulated lobular mass with variegated grey-brown cut surfaces, peripheral fatty areas, and foci of hemorrhage. Histopathological examination confirmed adrenal myelolipoma, demonstrating mature adipose tissue admixed with erythroid, myeloid, and megakaryocytic precursors without atypia, necrosis, or capsular invasion.Conclusion: This case highlights the importance of considering adrenal myelolipoma in the differential diagnosis of fat-containing adrenal masses. Surgical excision is recommended for symptomatic or large tumours. Histopathology remains the gold standard for diagnosis, exclusion of malignancy and guiding management. Prognosis is excellent with negligible recurrence risk.