POSTOPERATIVE METYRAPONE TEST IN THE EARLY ASSESSMENT OF OUTCOME OF PITUITARY SURGERY FOR CUSHINGS-DISEASE

OBJECTIVE The prediction of relapse during the early months after tran ssphenoidal surgery for Gushing's disease remains difficult. We have e valuated the usefulness of the postoperative metyrapone test in this s ituation. PATIENTS From a retrospective series of 77 consecutive prima ry pituitary operations for Gushing's disease 29 patients, who also ha d a metyrapone test at 14 days postoperatively, were selected, Median follow-up was 35 months (range: 8-118 months), MAIN OUTCOME MEASURES E arly postoperative: fasting morning serum cortisol, 24-hour urinary co rtisol excretion, serum 11-deoxycortisol after 6 x 750 mg metyrapone, Remission was defined as a fasting morning serum cortisol <140 nmol/l and/or 24-hour urinary cortisol excretion <250 nmol. During follow-up: serum cortisol, as well as serum cortisol in the 1 mg overnight dexam ethasone-suppression test was measured in order to detect relapse of G ushing's disease, RESULTS Twelve of 29 patients were not in remission after surgery, These patients all had serum 11-deoxycortisol levels >3 50 nmol/l after metyrapone, Seventeen patients met the criteria for ea rly remission, Four of these patients had serum 11-deoxycortisol level s between 150 nmol/l and 350 nmol/l after metyrapone, Three of these 4 patient's experienced a relapse of Gushing's disease during follow-up , In the 13 patients with a serum 11-deoxycortisol <150 nmol/l after m etyrapone, no relapse occurred, CONCLUSIONS The metyrapone test is a u seful test in the assessment of outcome of pituitary surgery for Gushi ng's disease, with a sensitivity of 100% and a specificity of 75% for the early detection of patients at risk of a relapse, Patients in whom a serum 11-deoxycortisol >150 nmol/L is found after metyrapone are at a high risk for relapse of Gushing's disease.