Functional ectopic adrenocortical carcinoma : a case report

Abstract

BACKGROUND: Adrenocortical carcinomas (ACC) are rare malignant tumours, with a quoted incidence of 0.7–2.0 cases/million habitants/year, with ectopic ACC being exceptionally rate. Diagnosis is based on clinical and biological assessment supplemented by imaging. Patients commonly present with features secondary to steroid excess, but around 15% of patients are diagnosed incidentally.

CASE REPORT: A 54-year old lady, presented to clinic for assessment of possible polycystic ovarian syndrome (PCOS). The patient gave a few months history of facial hirsutism accompanied by excessive weight gain and new onset hypertension. On further questioning, she had more sinister symptoms including easy bruising, proximal myopathy and insomnia. Initial investigations revealed a 0900 h cortisol of 867 nmol/l, testosterone 6.73 nmol/l, oestradiol of 129 pmol/l, DHEAS 2.50 umol/l, Androstenedione 9 (0.35-2.49) ng/ml, 17-hydroxyprogesterone of 24.8 ng/ml. 0900 h Cortisol post over-night Dexamethasone suppression test was 1482 nmol/l, ACTH was undetectable and 24-hour urinary cortisol >4138 nmol/24 hr (<806.8 nmol/24 hr).An abdominal CT revealed a 6 cm solid and irregular retroperitoneal mass, in the right iliac fossa, that was separate from the kidney. The lesion increased in size from 6.3 cm to 10.3 cm in 4 months. She had a surgical resection and histology revealed an adrenocortical carcinoma, with a Ki-67 score of 25% and 20 mitoses per high power field. On immunohistochemistry, the tumour cells were positive for melanin A, synaptophysin and inhibin. Post-operatively, the patient was given 6 cycles of etoposide, doxorubicin and cisplatin as Mitotane was locally unavailable, however it was agreed that this is initiated if there is evidence of metastatic disease during follow up. 0900 h Cortisol level on Day 3 post-operatively was 20 nmol/l. She was started on Hydrocortisone 20 mg-10 mg-10 mg peri-operatively, which was tailed down and eventually stopped 7 months later, once Synacthen test showed normal cortisol response. The patient has remained well and is under regular surveillance with the most recent imaging showing no evidence of disease recurrence.

CONCLUSION: Ectopic adrenocortical carcinomas are exquisitely rare tumours and can constitute an exceptional cause of ACTH-independent Cushing’s syndrome. Our case highlights such a functional tumour occurring in a very unusual location, secreting cortisol, androgens and other metabolites. Although very rare, it is an important condition to recognise because of the significant and sinister clinical sequalae that may develop.