Hypermineralocorticoidism due to adrenal carcinoma: plasma corticosteroids and their response to ACTH and angiotensin II.

A 47-year-old female presented with hypertension, hypokalaemia, low plasma renin, high plasma aldosterone and was found to have a left adrenal tumour 4 cm in diameter by computerized tomography. Detailed biochemical studies showed high plasma levels of 11-deoxycorticosterone and corticosterone in addition to aldosterone and 18-hydroxycorticosterone. Basal 11-deoxycorticosterone levels were particularly high. Corticosterone, 18-hydroxycorticosterone and aldosterone concentrations were abnormally sensitive to infusions of ACTH and angiotensin II. Plasma cortisol and assays for sex hormones were normal although there was evidence that cortisol derived from the neoplasm. At operation a well-differentiated adrenocortical carcinoma weighing 50 g (56 X 30 X 36 mm) was removed. There was no evidence of metastases following surgery. Adrenal function returned to normal. Review of the literature suggests that adrenocortical carcinoma should be suspected in patients who otherwise have typical features of Conn's syndrome, but whose tumours are more than 3 cm in diameter. Measurement of steroids such as 11-deoxycorticosterone in addition to aldosterone is recommended since abnormally high values may also help to distinguish between hyperaldosteronism due to adenoma and carcinoma. Previously reported cases of isolated aldosterone production by a carcinoma cannot be substantiated.