Lack of tumor reduction in hyperprolactinemic women with extrasellar macroadenomas treated with bromocriptine

Hyperprolactinaemia and the regular menstrual cycle in asymptomatic women: should it be treated during therapy for infertility?

It is known that hyperprolactinaemia can cause galactorrhoea and irregular cycles or even amenorrhoea. High serum prolactin (PRL) can disturb follicular maturation and corpus luteum function. Treatment of hyperprolactinaemia in patients with resulting bleeding anomalies is established, but the question is how to manage normal cyclic hyperprolactinaemic women? Studies have shown that in a subgroup of asymptomatic patients the serum contains mainly high molecular weight form (big big PRL), which has a low bioactivity, called macroprolactinaemia. It is evident that macroprolactin does not affect the control of pituitary PRL secretion via the short loop feedback mechanism or the secretion of gonadotrophins as does monomeric PRL. Identification of macroprolactinaemia is therefore clinically important to prevent unnecessary examinations and inappropriate treatment. Prolactinoma can be associated with macroprolactinaemia. Performance of pituitary imaging in asymptomatic patients with hyperprolactinaemia may therefore be justified, but further studies are needed to evaluate the relation of costs and benefit. An unsolved problem is the differentiation between inactive and PRL-secreting tumours. Caution should be exercised concerning medical treatment in unstimulated patients and also in patients during ovarian stimulation alone or in combination with intrauterine insemination or in-vitro fertilization. The potential clinical significance of hyperprolactinaemia/macroprolactinaemia in asymptomatic women must be further evaluated.

Prolactin disorders

OBJECTIVE

To review the pathophysiology, clinical manifestations, current diagnostic procedures, and treatment options for disorders involving PRL production. Common clinical dilemmas are discussed in a pragmatic fashion to guide the practitioner.

DESIGN

A world literature search of basic sciences and medical articles from the last three decades was performed using computerized MEDLINE. Recent endocrine and reproductive endocrine textbooks also were reviewed. Studies were selected for their degree of contribution to the basic sciences and clinical understanding of the disorder and for the quality of their study design and content. The information was summarized and grouped according to its relevance and application to specific sections of the manuscript. Studies were evaluated and critically used to support the views of the authors and to suggest specific clinical management strategies.

RESULT(S)

Disorders derived from abnormal PRL production are relatively common in clinical practice. Infertility, menstrual disorders, and galactorrhea are the most frequent manifestations encountered in women. Although frequently benign, the disorder occasionally may have severe consequences.

CONCLUSION(S)

An understanding of the underlying physiology and pathophysiology coupled with the awareness of the heterogeneous presentation of this disorder should help the clinician to approach it successfully.

Bromocriptine therapy for prolactin-secreting pituitary adenomas

An effective systematic approach for the management of prolactin-secreting pituitary adenomas is described. This methodology has stood the test of time and has been modified in accordance with experience. The primary goals are to obtain satisfactory control of the tumor and to avoid undesirable side effects related to dopamine agonist-based therapeutic agents.

Preoperative diagnosis of lymphocytic hypophysitis (adenohypophysitis) unresponsive to short course dexamethasone: case report

Lymphocytic hypophysitis (adenohypophysitis) is a rare lymphocytic infiltration of the pituitary gland that usually occurs during pregnancy. Because of its rarity, it has seldom been diagnosed preoperatively, and no trials of therapeutic treatment have been reported to date. We describe a 29-year-old woman with a pituitary mass and visual-field defects during pregnancy. The patient's pituitary profile revealed an abnormal thyroid axis and relatively low prolactin for her stage of pregnancy. This finding suggested adenohypophysitis, and the patient was given a trial course of dexamethasone. The progression of the visual-field defects, however, indicated that the steroids, both in dosage and duration, were not effective. Thus, the patient underwent a partial hypophysectomy for decompression. The pathology report confirmed adenohypophysitis, and steroids were continued for the remainder of the pregnancy, with slow resolution of the visual-field defects to normal. This report is the first case of adenohypophysitis where the diagnosis was suspected preoperatively, and a trial course of steroids was given. The steroids at the dosage and duration used were not effective. Further evaluation of the use of steroids in this disease is warranted.

Giant invasive prolactinomas

Two of the largest prolactinomas ever documented that have been followed for nine and 10 years, respectively, demonstrate how aggressive prolactinomas may become and how difficult invasive prolactinomas are to treat. One of these prolactinomas invaded both internal auditory canals and simultaneously grew inferiorly, reducing the bony support of the skull and necessitating the patient to utilize both hands to hold his head up. The second patient's prolactinoma invaded the sphenoidal, ethmoidal, and cavernous sinuses. Both of these patients had neurosurgical debulking of their tumors followed by radiation therapy. Neither patient's prolactin levels decreased significantly during their first five years post-surgically, at which time bromocriptine was added. Since then, there has been a gradual lowering of serum prolactin levels and a decrease in the size of these tumors. These cases demonstrate that prolonged treatment and very large doses of bromocriptine may be necessary for tumor reduction in patients with invasive prolactinomas.