Endocrine Abstracts

Prolactinoma is the most common cause of chronic hyperprolactinemi and drugs that rise serum prolactin levels have been ruled out. Altough almost all of them arise within the sella turcica, there are some rare cases in which prolactinoma is located outside the intrasellar region, so it is defined as ectopic prolactinoma. Neuroleptics (e.g., haloperidol, chlorpromazine, risperidone.) can elevate serum PRL to levels that usually are detected with prolactinomas. We report a case ectopic prolactinoma within the clivus with empty sella in a patient using risperidone and paroxetine.

Case: A 46-year-old woman was referred to the endocrinology clinic for investigation of her clinical presentation of galactorrhea and amenorrhea. She had been taking risperidone two years for the treatment of psychosis. During the admission the physical and neurological examinations of the patient were normal. The complete blood count values and basic serum levels of the biochemical parameters were normal. The hormonal parameters were as follows: St4 12.9 pmol/l (normal referece;12.8–20.4), TSH 1.52 uIU/ml (0.4–3.77), IGF-1 92.9 ng/ml (74-196), and GH 0.014 ng/ml (0—5), FSH 0.7 IU/l (3.5–12.5), LH 0.9 IU/l (2.4–12.6), estradiol 14.6 pg/ml (5–54.7), PRL >470 ng/ml (6–29.9). Medication-induced hyperprolactinemia was suspected, and after psychiatric consultation, paroxetine and risperidone were stopped and aripiprazol was begun. After 30 days, her prolactin level was again >470 ng/ml and after withdrawing the medications, her symptoms not resolved. Pituitary MRI showed homogeneously enhancing mass within the clivus and basisphenoid associated with an empty sella (figure A,B,C). A mass at the level of the clivus with empty sella, combined with very high prolactin levels, suggested the diagnosis of an ectopic prolactinoma. Because of ammnorhea, possibly due to this tumour, the patient was treated with the longacting dopamine agonist, cabergoline, in a dose of 2×0.5 mg weekly. Prolactin levels dropped from >470 ng/ml to 405 ng/ml in four weeks and to 214 ng/ml in eight weeks and to 16 ng/ml in twelve weeks.The treatment was well tolerated by the patient and complaints of galactorrhea and amenorrhea subsided, with the normalisation of the prolactin levels. A control MRI after 6 months illustrated a minimal reduction in the volume of the adenoma (Figure D). The dose of cabergoline was reduced after six months to 0.5 mg weekly, with the continuation of normal prolactin levels.