Phaeochromocytoma in association with hypercortisolism is thought to be rare. However we have observed 4 cases in 3 years and question the rarity of this link. In each case there was a dominant adrenal mass (3.6-7.7cm) with contralateral adrenal hyperplasia. Three of the 4 tumours showed increased 123-I-mIBG uptake. Urinary catecholamines ranged from 872-22752nmol/24h (N < 600). Hypercortisolism was present in all 4 patients; sustained in 2 and cyclical in 2. Case 1 (JCEM 2000,85: 4771): 44-yr old woman with an ectopic ACTH syndrome (K+=2.3mmol/l, serum cortisol>1660nmol\/l, ACTH 200pmol\/l (N<12)). ACTH precursors were 1625pmol/l (N 5-40). Tumour cells cultured in-vitro secreted ACTH precursors, while ACTH levels were undetectable. In-vitro and in-vivo evidence suggested that glucocorticoids induced ACTH precursor secretion. Case 2: 77-yr old woman with an ectopic ACTH syndrome (serum cortisol 2800nmol/l, ACTH 211pmol/l, ACTH precursors 1250pmol/l). ACTH / ACTH precursors fell after surgery but in-vitro secretion could not be demonstrated. Case 3: 61-yr old woman with cyclical (1 pulse/ 3 weeks) Cushing's syndrome (urinary cortisol\/creatinine ratios 10-137 (N<25μmol\/mol creat) and serum cortisol 270-480mmol/l. Serum ACTH and ACTH precursors were in the normal range (serum IL6 was mildly elevated preoperatively). Case 4: 63-yr old woman with cyclical Cushing's syndrome (peak urinary cortisol 634nmol\/24h (N<275), peak serum cortisol 860nmol\/l, ACTH / ACTH precursors normal).
Comment: Phaeochromocytoma appears to be more commonly associated with hypercortisolism than generally believed. Cases 1 and 2 were clearly ACTH dependent and the patients were steroid dependent postoperatively. Cases 3 and 4 had cyclical Cushing's syndrome with rapid recovery of the HPA function postoperatively. We are investigating the possibility of cytokine mediated hypercortisolism in case 3 and 4.
08 - 11 Apr 2002
British Endocrine Societies