Adrenal cortical adenoma is a benign epithelial tumour derived from adrenal cortical cells. Most cases present as a unilateral, solitary, and well-circumscribed nodule. Symptoms depend on the hormonal secretory status of the tumour which can produce cortisol, aldosterone, androgens, estrogens, or can be non-functioning. Microscopically tumours show varying proportions of clear or oncocytic cells arranged in chords or nests in a background of abundant small and medium-sized blood vessels. Additionally, the cells can have uniform nuclei, abundant intracytoplasmic lipid droplets, and inclusions. By immunohistochemistry, the tumour cells are commonly positive for makers normally expressed by adrenal cortical cells including inhibin, calretinin, SF1, CD56, and Melan-A.