Endocrine Abstracts

Serum androgen levels are commonly suppressed in patients with benign cortisol-secreting adrenocortical adenomas due to ACTH suppression. Associated androgen co-secretion usually indicates malignancy. Here, we present a case a very large benign androgen and cortisol-secreting adrenocortical neoplasm.

Case: A 24-year-old female was referred with a 1-year history of secondary amenorrhea associated with hirsutism and acne. She reported irregular menstrual cycles prior to the development of amenorrhea. On clinical examination purple striae were observed over flanks with no other Cushingoid features or abnormalities found on examination. Initial blood tests revealed elevated testosterone (11.3 nmol/l), androstenedione (58.0 nmol/l), DHEA-S (55 μmol/l), and free androgen index (56.8%). 17-OH progesterone, plasma renin:aldosterone ratio and urinary metanephrines levels were normal. Further testing revealed failure to suppress cortisol following an overnight dexamethasone suppression test (562 nmol/l), coupled with low ACTH (<5 ng/l). A cortisol day curve and a low-dose dexamethasone suppression tests confirmed cortisol over-secretion (cortisol 483 nmol/l and nadir levels of 430 nmol/l respectively). Subsequently adrenal MRI revealed a large right-sided 12×9 cm heterogeneous adrenal tumour. Patient underwent an open right adrenalectomy with post-operative hydrocortisone replacement. Histo-pathological analysis revealed findings consistent with a benign adrenal cortical neoplasm; Weiss score 2 with Ki-67 proliferation index of 1–2%.

Conclusion: Case studies have shown that adrenal mass size is strongly linked to malignant potential, with most benign adenomas limited to <4 cm. Most centres use tumour size of 5–6 cm or greater as an absolute indication for resection due to the high risk of malignancy (35–98%). This case is unusual in that despite the substantial size of the adrenal mass and its hormone secreting properties, the lesion was found to be benign. High levels of adrenal androgens can also be seen in benign adreno-cortical tumours.