Subclinical Cushing’s in a case of adrenal incidentaloma.

Valsalakumari P, Acharya J, Akavarapu S, Thukral S, Palazzo F, Todd JF


A 52 year old lady was referred to our endocrine services after a left retroperitoneal adrenalectomy for an adrenal incidentaloma.  Her past medical history is significant for lymph node positive invasive ductal carcinoma grade 2 with vascular invasion. She has had a modified radical mastectomy with radiotherapy and chemotherapy and currently is on Tamoxifen. Staging CT scan for breast cancer showed a left 3.5 cm adrenal incidentaloma “well defined with pre contrast Hounsfield units <12 and absolute washout of 8%” and it was removed. Post operatively she was found to have a cortisol of <20nmol/l suggestive of subclinical cushing’s syndrome. Histopathology showed a left benign adreno-cortical adenoma.


She also has primary hypothyroidism for which she takes Levothyroxine 125mcg daily. There is no history of diabetes or hypertension.


She was commenced on hydrocortisone replacement dose and recovered well. On a follow up visit, she was quite keen to come off steroids. A short synacthen test was organised 2 months after surgery which showed an adequate rise of cortisol to 568nmol/l suggestive of adrenal recovery and hydrocortisone was stopped.  She continues to remain very well without any evidence of local recurrence of the tumor.

Incidentally discovered adrenal masses are mostly benign lesions, often arbitrarily considered as nonfunctioning tumors. Recent studies, however, have reported increasing evidence that subtle cortisol production and abnormalities in the hypothalamic-pituitary-adrenal (HPA) axis are more frequent than previously thought. Laparoscopic adrenalectomy performed by skilled surgeons appears more beneficial than conservative management for these patients with a subsequent improvement in metabolic and hormonal abnormalities. General view that surgical resection should be reserved for those with worsening of hypertension, abnormal glucose tolerance, dyslipidemia, or osteoporosis is debatable as little information is available about the natural history of this condition.