Guidelines of the Pituitary Society for the diagnosis and management of prolactinomas

Pituitary Adenomas: What Are the Key Features? What Are the Current Treatments? Where Is the Future Taking Us?

Pituitary tumors are a heterogeneous group of lesions (usually benign) and proper understanding of the anatomy, physiology, and pathology of the hypothalamic/pituitary region is essential to make an accurate diagnosis and define the essential treatment options (i.e., surgery, medical therapies, and radiotherapy, alone or in combination). Surgery is the primary treatment for acromegaly, Cushing disease, thyroid-stimulating hormone-secreting adenomas, resistant prolactinomas, and nonfunctioning pituitary adenomas causing mass effect. Medical and radiation therapy are reserved in cases in which surgery is not possible or does not provide a complete cure. In the last decades, tremendous innovations (i.e., targeted drugs and refined surgical tools and techniques) have expanded the treatment strategies for pituitary adenomas. We herein report the current indications for and depiction of the surgical techniques in pituitary surgery, review current medical treatments, and provide a glimpse of future possibilities.

The Association Between Prolactin and Metabolic Parameters in PCOS Women: A Retrospective Analysis

Background: The aim of this retrospective study was to analyze the association between prolactin (PRL) and metabolic parameters in infertile patients with polycystic ovary syndrome (PCOS). Methods: A total of 2,052 patients with PCOS and 9,696 patients with tubal infertility (non-PCOS) undergoing in vitro fertilization and embryo transfer (IVF-ET) at the reproductive medicine center of the first affiliated hospital of Wenzhou Medical University from January 2007 to July 2017 were enrolled in this study. Serum PRL, basic endocrine hormones, fasting plasma lipid, fasting plasma glucose (FPG), liver function, thyroid hormone and other parameters were measured and analyzed. Result: PRL levels were significantly lower in PCOS patients than controls over all age groups (p < 0.05). In the PCOS patients, serum PRL was significantly and positively correlated with FPG, serum TSH and serum FT4, and significantly and negatively correlated with LH, LH/FSH, TC, TG, LDL-C, AST, ALT, γ-GGT, FT3, and FT3/FT4 (p < 0.05 or 0.01). After adjusted for age and body mass index (BMI), serum PRL was positively correlated with FPG, TSH, and FT4, and negatively correlated with LH and LH/FSH. Conclusion: Low serum PRL may be an important cause of metabolic risk in infertile patients with PCOS.

Malignant Prolactinoma With Liver Metastases Masquerading as Metastatic Gastrointestinal Stromal Tumor: A Case Report and Literature Review

Pituitary carcinomas are rare diseases defined as pituitary tumors with metastases. In this report, we describe a case of malignant prolactinoma with liver metastases masquerading as metastatic gastrointestinal stromal tumor (GIST). A 54-years-old woman received dopamine agonists for macroprolactinoma for 2 years, followed by transsphenoidal surgery due to a poor response to medical therapy. Despite the continuation of dopamine agonist after surgery, serum prolactin level progressively increased to above 8,000 ng/ml in 5 years. There was no evidence of disease recurrence on sella magnetic resonance imaging (MRI). She stopped medical therapy. Meanwhile, she was diagnosed with GIST accompanied by liver and peritoneal metastases. After a 2-months treatment with imatinib, she suddenly presented with headache and visual impairment. Sella MRI showed a 3.3-cm sized pituitary mass, and serum prolactin levels were still high. For the recurred mass, she underwent a second surgery followed by radiation therapy. During the imatinib treatment for GIST, main mass and peritoneal metastases were dramatically decreased, but liver metastases were markedly aggravated. Liver masses were eventually confirmed as metastases from prolactin-producing pituitary carcinoma and not from GIST by percutaneous biopsy. Unfortunately, she died 6 months after the second surgery due to acute renal failure and sepsis. This case suggests that highly sustained serum prolactin levels during the dopamine agonist may indicate prolactin-producing pituitary carcinomas with hidden metastases.

Surgical management considerations in cystic prolactinomas-a single center case series

PURPOSE

The optimal treatment of prolactinomas with a predominantly cystic component remains poorly defined. The cystic tumor component is considered to respond less favorably to medical treatment, thereby advocating surgical management. The purpose of this study was to assess remission rates in surgically treated cystic prolactinomas, and to compare outcomes to similarly treated solid micro- and macroprolactinomas.

METHODS

Clinical and imaging data were retrospectively compiled from 56 patients who underwent transsphenoidal resection, for symptomatic prolactinomas, from 2004 to 2018, at a single academic institution. Pituitary adenomas were subdivided according to tumor size and tumor consistency: cystic prolactinomas (>50% cystic tumor component) n = 17; solid microprolactinomas (<10 mm) n = 10; and solid macroprolactinomas (≥10 mm) n = 29. Remission was defined as a prolactin level of <10 ng/dl either immediately postoperative or at a later time point.

RESULTS

Median tumor size was 15 mm for cystic prolactinomas, 7 mm for solid microprolactinomas, and 25.5 mm for solid macroprolactinomas. Remission was achieved in 76% (n = 13/17) of surgically treated cystic prolactinomas, 100% (n = 10/10) of solid microprolactinomas, and 24% (n = 7/29) of solid macroprolactinomas. More than 44% of solid macroprolactinomas had a Knosp grade > 3, while most cystic prolactinomas (93.8%) and all solid microprolactinomas (100%) had a Knosp grade ≤ 2.

CONCLUSIONS

Despite their large tumor size (≥10 mm), high remission rates can be expected with surgically treated cystic prolactinomas. This case series of cystic prolactinomas demonstrates the successful use of transsphenoidal surgery as a favorable, and a potentially curative alternative to dopaminergic therapy in this patient population.

Hyperprolactinaemia

Hyperprolactinaemia is one of the most common problems in clinical endocrinology. It relates with various aetiologies (physiological, pharmacological, pathological), the clarification of which requires careful history taking and clinical assessment. Analytical issues (presence of macroprolactin or of the hook effect) need to be taken into account when interpreting the prolactin values. Medications and sellar/parasellar masses (prolactin secreting or acting through “stalk effect”) are the most common causes of pathological hyperprolactinaemia. Hypogonadism and galactorrhoea are well-recognized manifestations of prolactin excess, although its implications on bone health, metabolism and immune system are also expanding. Treatment mainly aims at restoration and maintenance of normal gonadal function/fertility, and prevention of osteoporosis; further specific management strategies depend on the underlying cause. In this review, we provide an update on the diagnostic and management approaches for the patient with hyperprolactinaemia and on the current data looking at the impact of high prolactin on metabolism, cardiovascular and immune systems.

Pituitary Dysfunction Among Men Presenting with Hypogonadism

PURPOSE OF REVIEW

Hypogonadism is a common endocrine dysfunction. This review focuses on the most up-to-date guideline for evaluation of pituitary function among men presenting with signs and symptoms of hypogonadism.

RECENT FINDINGS

The clinician must differentiate between primary (testicular) and secondary (pituitary-hypothalamic or central) hypogonadisms and be aware of adult-onset hypogonadism. If gonadotropins are low or inappropriately normal, the clinician must consider potential reversible causes in the hypothalamus-pituitary axis. Also, it is critical to understand the pitfalls of testosterone testing. When clinically indicated, evaluation of other pituitary hormone functions as well as pituitary magnetic resonance imaging may be necessary. Furthermore, it is essential to recognize that pituitary incidentalomas are common. Patients with microprolactinoma are more likely to present with symptoms of sexual dysfunction while those with macroprolactinoma are more likely to present with symptoms of mass effect. Some functional pituitary tumors respond to drug therapy while other nonfunctional tumors require surgical intervention. It is important for the clinician to understand the proper work-up of the hypogonadal patient with pituitary dysfunction and when necessary to refer to an endocrinologist or a neurosurgeon.

Predicting early post-operative remission in pituitary adenomas: evaluation of the modified knosp classification

PURPOSE

Cavernous sinus invasion by pituitary adenomas is an important prognostic factor for evaluating the possibilities of complete remission and to guide patient management. A widely used Magnetic Resonance Imaging grading system, suggested by Knosp in 1993, has recently been revised by the same group. The aims of our study were to apply this revised grading system to our surgical series, to determine its association with surgical outcomes, gross-total resection (GTR) and endocrinological remission (ER), paying particular attention to grades 3A and 3B, which represent the novelty of this revised classification.

METHODS

We included consecutive patients who underwent endoscopic endonasal surgery for a macroadenoma from September 2012 to December 2016. MRI images were reviewed and classified according to the revised Knosp classification. Surgical reports indicated the intra-operative CS invasion. GTR and ER were evaluated on 3-months post-operative MRI and endocrine evaluation.

RESULTS

254 patients were included in this study. We found a total rate of cavernous sinus invasion of 18.4%. Different outcomes were observed for each grade, with an increased rate of cavernous sinus invasion with each grade. Per-operative rates of invasion were 61.5 and 78.6% in grades 3A and 3B respectively. GTR was negatively correlated with the grade, while rates were 55.8% and 30.0% for grades 3A and 3B respectively.

CONCLUSION

The revised Knosp radiological classification contributes to the prediction of surgical outcomes and early ER in pituitary adenomas. To manage, as precisely as possible, the risk of early recurrence in pituitary adenomas, clinicians should also consider other recognized prognostic factors, such as the proliferative status of the tumor.

MiR-1299 promotes the synthesis and secretion of prolactin by inhibiting FOXO1 expression in drug-resistant prolactinomas

Prolactinoma is a clinically common intracranial tumor. When serum prolactin levels are not controlled despite administration of a dopamine agonist, the condition is referred to as drug-resistant prolactinoma. The mechanism underlying persistent prolactin secretion in drug-resistant prolactinoma remains unclear. MicroRNAs play an important role in tumorigenesis and development as well as chemotherapeutic resistance. This study was conducted to investigate the mechanism by which miRNA regulates prolactin secretion in drug-resistant prolactinoma. We first found that miR-1299 was elevated in drug-resistant prolactinoma and inhibited FOXO1 in a targeted manner through miRNA sequencing and luciferase assays. We then confirmed that FOXO1 binds to the promoter of the prolactin gene to inhibit its expression through chromatin immunoprecipitation-quantitative PCR and cytological experiments. Finally, inhibition or overexpression of miR-1299 in primary tumor cells confirmed that drug-resistant prolactinoma promoted prolactin secretion by promoting miR-1299 expression and reducing intracellular FOXO1. These results indicate that FOXO1 and miR-1299 are potential therapeutic targets for drug-resistant prolactinoma as well as other pituitary diseases.

Start low, go slowly - mental abnormalities in young prolactinoma patients under cabergoline therapy

Background Prolactin-secreting pituitary adenomas in childhood and adolescence are rare. First-line therapy consists of dopamine agonists (DAs) like cabergoline. Experience in treating prolactinomas in paediatric and adolescent patients is limited. Methods This study was a retrospective analysis of clinical data, laboratory data, radiological findings and medical treatment of paediatric and adolescent patients with prolactinomas between 2009 and 2018. Results Our cohort of nine patients had a median age at diagnosis of 13 years (range 5-17). Main presenting symptoms were weight gain, disorders of the pituitary-gonadal axis and headache. Treatment with cabergoline resulted in a marked reduction in prolactin concentration in all nine patients. Tumour mass reduction was confirmed by magnetic resonance imaging (MRI) scan in seven patients. Noteworthy is that cabergoline therapy triggered frequent adverse effects in a total of eight patients - seven of whom suffered from mental disorders, five of whom had neurological symptoms and five of whom had gastrointestinal problems. The adverse effects occurred at a median dose of only 0.5 mg/week (range 0.25-2.0). Most symptoms were alleviated after the cabergoline dose was lowered. Therapy discontinuation was not necessary in any patient. Conclusions Cabergoline effectively lowers prolactin levels and may reduce tumour mass in paediatric and adolescent patients with prolactinomas. Potential adverse effects may include mental disorders and behavioural problems even at low cabergoline doses. Low starting doses and careful individual dose adjustments are required to enable therapy adherence.

PCOS and Hyperprolactinemia: what do we know in 2019?

Polycystic ovary syndrome (PCOS) and hyperprolactinemia (HPRL) are the two most common etiologies of anovulation in women. Since the 1950s, some authors think that there is a pathophysiological link between PCOS and HPRL. Since then, many authors have speculated about the link between these two endocrine entities, but no hypothesis proposed so far could ever be confirmed. Furthermore, PCOS and HPRL are frequent endocrine diseases and a fortuitous association cannot be excluded. The evolution of knowledge about PCOS and HPRL shows that studies conducted before the 2000s are obsolete given current knowledge. Indeed, most of the studies were conducted before consensual diagnosis criteria of PCOS and included small numbers of patients. In addition, the investigation of HPRL in these studies relied on obsolete methods and did not look for the presence of macroprolactinemia. It is therefore possible that HPRL that has been attributed to PCOS corresponded in fact to macroprolactinemia or to pituitary microadenomas of small sizes that could not be detected with the imaging methods of the time. Recent studies that have conducted a rigorous etiological investigation show that HPRL found in PCOS correspond either to non-permanent increase of prolactin levels, to macroprolactinemia or to other etiologies. None of this recent study found HPRL related to PCOS in these patients. Thus, the link between PCOS and HPRL seems to be more of a myth than a well-established medical reality and we believe that the discovery of an HPRL in a PCOS patient needs a standard etiological investigation of HPRL.

Pituitary Tumors in Pregnancy

Pituitary adenomas are common. The impact of pituitary tumors on fertility are mainly caused by oversecretion and/or undersecretion of pituitary hormones or compression of pituitary stalk and normal pituitary tissue by the tumor. Diagnosing and managing pituitary tumors during pregnancy involve many challenges, including the effect of hormone excess or deficiency on pregnancy outcome, changes in the pituitary or pituitary-related hormones, changes in tumor size, and the impact of various treatments of pituitary tumors on maternal and fetal outcomes. This article discusses the diagnosis and treatment of patients with prolactinomas, acromegaly, Cushing disease, and other pituitary tumors during pregnancy.

The Role of Surgery in the Management of Prolactinomas

Prolactinomas are the most common functional pituitary adenoma. Many prolactinomas can be treated with medication, but all patients should be evaluated at a neuroendocrine center including experienced neurosurgeons trained in transsphenoidal surgery. Surgery for prolactinomas is feasible and can be performed with low morbidity. Patients never previously treated with dopamine agonists should be considered for surgery if they have neurologic deficits, pituitary apoplexy, an uncertain diagnosis, or a significantly cystic prolactinoma. Patients previously treated with dopamine agonists should be considered for surgery in cases of intolerance or resistance. Recurrent and aggressive prolactinomas often require multimodal therapy.

Serum prolactin overestimation and risk of misdiagnosis

BACKGROUND

Falsely elevated prolactin measurements risk overdiagnosis, and unnecessary imaging and treatment.

DESIGN

We conducted a clinical audit of 18 patients who presented with hyperprolactinaemia, followed by a laboratory audit of 40 split samples across a range of serum prolactin (5-5051 mIU/L). In each case (total n = 58), serum prolactin was measured on both Roche and Siemens platforms.

RESULTS

Serum prolactin as measured by Roche was higher than the corresponding Siemens value in every case, despite similar reference ranges. The mean discrepancy in serum prolactin by Roche vs. Siemens was +81% in the clinical audit and +50% in the laboratory audit. This led to unnecessary interventions in 7/18 patients (39%) in the clinical audit.

CONCLUSIONS

Serum prolactin is overestimated on the Roche relative to the Siemens platform. Laboratories should review Roche reference intervals for serum prolactin, and clinicians should consider repeating serum prolactin on another platform if the serum prolactin is incongruent with the clinical scenario.

Increased expression of aromatase cytochrome P450 enzyme is associated with prolactinoma invasiveness in post-menopausal women

Objectives

To investigate the expression levels of aromatase cytochrome P450 enzyme (P450AROM) and related molecules—estrogen receptor-beta (ER-β), Ki-67, and p53—in prolactinoma tumor tissue from pre- and post-menopausal women, and to determine the associations of tumor invasiveness with expression levels of these genes.

Methods

This study recruited 90 patients with prolactinoma who underwent adenoidectomy between 2012 and 2017. Information was collected regarding clinical characteristics, hormones, laboratory tests, and magnetic resonance imaging-assessed tumor invasiveness. Expression levels of P450AROM, ER-β, Ki-67, and p53 were examined by immunohistochemistry in prolactinoma tissues.

Results

Increased P450AROM expression was found in invasive prolactinoma tissues in post-menopausal women, compared with its expression in non-invasive prolactinoma tissues. ER-β level was significantly higher in patients resistant to treatment with bromocriptine, a dopamine agonist. However, there were no differences in rate of resistance to treatment (8.2% vs. 3.4%) or expression levels of P450AROM, Ki-67, p53, and ER-β between pre- and post-menopausal patients.

Conclusions

Our results demonstrated that increased P450AROM expression in prolactinoma of post-menopausal women was positively associated with invasiveness. Moreover, ER-β level was higher in both pre- and post-menopausal patients who were resistant to dopamine agonist treatment.

Chemometric Expertise Of Clinical Monitoring Data Of Prolactinoma Patients

The present investigation indicates hidden relationships between the several clinical parameters usually monitored on prolactinoma patients using non-hierarchical cluster analysis. The major goal of the chemometric data mining is to offer a possible mode of optimization of the monitoring procedure by selecting a reduced number of health status indicators. The intelligent data analysis reveals the formation of three patterns of prolactinoma patients each one of them described by a set of clinical parameters. Thus, better strategies for considering patients with this diagnosis could be developed and clinically applied.

Prolactin, prolactin disorders, and dopamine agonists during pregnancy

Pituitary disorders, and especially prolactinomas, are not common among pregnant women, though they tend to occur during a woman's years of fertility. The majority of prolactinoma patients present with infertility and menstruation dysfunction; however, prolactinomas are associated with potentially significant morbidity if they remain unrecognized and untreated. Herein, we survey the role of prolactin and prolactinomas in pregnancy while also outlining the therapeutic approach to prolactinoma during pregnancy. The current literature on the impact of dopamine agonists during pregnancy is also reviewed.

Gestational pituitary apoplexy: Case series and review of the literature

Pituitary apoplexy is an uncommon but potentially life-threatening emergency due to abrupt ischemic infarction or hemorrhage of the pituitary tumor. In many instances, pituitary apoplexy is the initial presentation in patients who were not previously diagnosed to have pituitary adenomas. Variety of precipitating factors have been linked to the occurrence of pituitary apoplexy, which include pregnancy. However, pituitary apoplexy related to pregnancy is limited to isolated case reports and very small case series. The main symptom is headache of sudden onset associated with visual disturbances, signs of meningeal irritation, and/or endocrine dysfunction. In the context of pregnancy the diagnosis of pituitary apoplexy can be challenging and confused with other complex conditions such as pre-eclampsia. Magnetic resonance imaging is the most sensitive sequence to confirm the diagnosis by revealing a pituitary tumor with hemorrhagic and/or necrotic components. Corticotropic deficiency with adrenal insufficiency is a potentially life-threatening disorder for both mother and the fetus if left untreated. The choice between conservative management with dopamine agonists and glucocorticoid, this "wait and see approach" and trans-sphenoidal resection depend on the severity of neuro-ophtalmic signs and the gestational week. In this article, we present three cases of pituitary apoplexy related to pregnancy. Pituitary apoplexy occurred in the third trimester in the three cases. It was the first presentation of an unknown pituitary adenoma in two cases, and complicated a preexisting macroprolactinoma in the other case. All three cases of our patients had sudden onset of severe headache and deterioration of the visual field in two cases. The pituitary MRI performed in our patients was the essential tool confirming the diagnosis of pituitary apoplexy. In all the patients was prompt replacement of deficient hormones especially glucocorticoids with close surveillance. The trans-sphenoidal resection was indicated in two pregnant women; as the first choice treatment in one case presenting with papillary edema, and as the second line after the deterioration of the visual field in one case. In the lack of guidelines of management pituitary apoplexy in case of pregnancy, we review the existing literature with pertinent clinical presentation, radiological findings, management and maternal/fetal outcomes of this rare pathology. The aim is to provide a rational framework for therapeutic management of pituitary apoplexy during pregnancy.

Echocardiography and monitoring patients receiving dopamine agonist therapy for hyperprolactinaemia: A joint position statement of the British Society of Echocardiography, the British Heart Valve Society and the Society for Endocrinology

This is a joint position statement of the British Society of Echocardiography, the British Heart Valve Society and the Society for Endocrinology on the role of echocardiography in monitoring patients receiving dopamine agonist (DA) therapy for hyperprolactinaemia. Evidence that DA pharmacotherapy causes abnormal valve morphology and dysfunction at doses used in the management of hyperprolactinaemia is extremely limited. Evidence of clinically significant valve pathology is absent, except for isolated case reports around which questions remain. Attributing change in degree of valvar regurgitation, especially in mild and moderate tricuspid regurgitation, to adverse effects of DA in hyperprolactinaemia should be avoided if there are no associated pathological changes in leaflet thickness, restriction or retraction. Note must be taken that even where morphological change in leaflet structure and function may be suspected, grading is semi-quantitative on echocardiography and may vary between different machines, ultrasound settings and operators. Decisions regarding discontinuation of medication should only be made after review of serial imaging by an echocardiographer experienced in analysing drug-induced valvulopathy or carcinoid heart disease. A standard transthoracic echocardiogram should be performed before a patient starts DA therapy for hyperprolactinaemia. Repeat transthoracic echocardiography should then be performed at 5 years after starting cabergoline in patients taking a total weekly dose less than or equal to 2 mg. If there has been no change on the 5-year scan, repeat echocardiography could continue at 5-yearly intervals. If a patient is taking more than a total weekly dose of 2 mg, then annual echocardiography is recommended.

MANAGEMENT AND OUTCOMES OF GIANT PROLACTINOMA: A SERIES OF 71 PATIENTS

Objective: To describe outcomes of patients with giant prolactinoma (≥4 cm) and identify predictors of therapeutic response. Methods: In this retrospective study, complete biochemical and structural response were defined as prolactin (PRL) ≤25 ng/mL and no visible tumor at follow-up, respectively. Results: Giant prolactinoma (median size, 4.8 cm [range, 4 to 9.8 cm]; median PRL, 5,927 ng/mL [range, 120 to 100,000 ng/mL]) was diagnosed in 71 patients. Treatments included: dopamine agonists (DAs) (n = 70, 99%), surgery (n = 30, 42%), radiation (n = 10, 14%), and somatostatin analogs (n = 2, 3%). Patients treated with DA monotherapy were older compared with those who received subsequent therapies (47 years vs. 28 years; P = .003) but had similar initial PRL and tumor size. Surgically managed patients were younger compared with the nonsurgical group (35 years vs. 46 years; P = .02) and had lower initial PRL (3,121 ng/mL vs. 6,920 ng/mL; P = .02), yet they had similar tumor response. Hypopituitarism was more common following surgery compared to medical management: adrenal insufficiency (69% vs. 27%; P<.001), hypothyroidism (67% vs. 38%; P = .02), growth hormone deficiency (24% vs. 6%; P = .04), and diabetes insipidus (17% vs. 3%; P = .04). Therapeutic response did not correlate with sex, age, initial PRL, tumor size, or first-line therapy mode. At median follow-up of 4.8 years, the median PRL was 18.3 ng/mL (range, 0.6 to 12,680 ng/mL), and final volume was 0.9 cm³ (range, 0 to 43.0 cm³). In those with available data, 36/65 (55%) patients achieved PRL normalization, and 16/61 (26%) had no visible tumor at follow-up. Conclusion: Most patients with giant prolactinoma have excellent response to DA. Sex, age, initial PRL, and tumor size do not predict therapeutic response. Abbreviations: BRC = bromocriptine; CAB = cabergoline; CSF = cerebrospinal fluid; DA = dopamine agonist; MRI = magnetic resonance imaging; PRL = prolactin.

Cabergoline Withdrawal Before and After Menopause: Outcomes in Microprolactinomas

Natural course of prolactinomas after menopause is not fully elucidated. The aim of this study was to compare recurrence rate after cabergoline withdrawal in premenopausal vs. postmenopausal women with microprolactinoma. Sixty-two women with microprolactinoma treated with cabergoline for at least 1 year and followed for 2 years after drug withdrawal were retrospectively selected. Patients were divided into two groups: 48 patients stopped cabergoline before menopause ("PRE" group), while 14 after menopause ("POST" group). Recurrence was defined by prolactin levels above normal, confirmed on two occasions. Overall, 39/62 women relapsed. Patients who relapsed apparently had higher prolactin before withdrawal (median 216.2, range 21.2-464.3 mIU/L) compared with those in long-term remission (94.3, 29.7-402.8 mIU/L; p < 0.05), and the risk of recurrence seemed lower in POST women (4/14, 29%) than in PRE ones (35/48, 73%, p < 0.005, OR 0.149, 95% CI 0.040-0.558). However, none of the factors (prolactin before withdrawal, menopausal status, treatment duration, complete adenoma regression) showed a correlation with recurrence risk in multivariate analysis. The best strategy able to optimize CBG treatment and withdrawal's outcomes is still to be defined in microprolactinomas. Postmenopausal status cannot reliably predict long-term remission, and follow-up is needed also in women of this age.

The epidemiology, diagnosis and treatment of Prolactinomas: The old and the new

Prevalence and incidence of prolactinomas are approximately 50 per 100,000 and 3-5 new cases/100,000/year. The pathophysiological mechanism of hyperprolactinemia-induced gonadotropic failure involves kisspeptin neurons. Prolactinomas in males are larger, more invasive and less sensitive to dopamine agonists (DAs). Macroprolactin, responsible for pseudohyperprolactinemia is a frequent pitfall of prolactin assay. DAs still represent the primary therapy for most prolactinomas, but neurosurgery has regained interest, due to progress in surgical techniques and a high success rate in microprolactinoma, as well as to some underestimated side effects of long-term DA treatment, such as impulse control disorders or impaired quality of life. Recent data show that the suspected effects of DAs on cardiac valves in patients with prolactinomas are reassuring. Finally, temozolomide has emerged as a valuable treatment for rare cases of aggressive and malignant prolactinomas that do not respond to all other conventional treatments.

Pituitary adenomas in patients with multiple endocrine neoplasia type 1: a single-center experience in China

PURPOSE

To explore the clinical characteristics of pituitary adenomas in patients with MEN1 and to summarize treatment strategies for MEN1 in a Chinese population.

METHODS

We retrospectively analyzed 54 MEN1 patients with pituitary adenomas diagnosed at Peking Union Medical College Hospital from March 2003 to January 2017. Clinical data, laboratory testing results, treatments of involved glands and treatment responses were collected and analyzed.

RESULTS

The mean age at pituitary adenoma diagnosis was 53.9 ± 17.8. The patients initially consulted the Endocrinology, General Surgery and Neurosurgery departments, in descending frequency. The nonfunctioning adenoma, prolactinoma, GH-secreting adenoma, cosecreting adenoma, and ACTH-secreting adenoma subtypes accounted for 48.1%, 27.8%, 9.3%, 9.3% and 5.6% of the cases, respectively. The remission rate for prolactinomas was 46.2% (6/13) treated with bromocriptine. And the remission rates were 87.5% (7/8) and 100% (3/3) for GH-secreting adenomas and ACTH-secreting adenomas respectively achieved by transsphenoidal surgery. Nineteen (35.2%) patients with asymptomatic nonfunctioning pituitary adenomas showed no progression after a 35-month follow-up with close observation. Regarding treatment priority, patients with thymic carcinoid tumors received first-line surgery, 54% of the patients with enteropancreatic tumors had these tumors treated first, and 26% of all patients had their pituitary adenomas treated first. In acromegalic patients, pituitary lesions tended to be treated first (75%, p = 0.002). PHPT and adrenocortical adenomas can be managed with elective surgery.

CONCLUSIONS

The treatment of MEN1 requires cooperation between multidisciplinary teams. Individualized treatment according to the severity of glandular involvement is needed. GH-secreting and ACTH-secreting pituitary adenomas require active treatment, while nonfunctioning pituitary adenomas can be observed closely.

Echocardiography and monitoring patients receiving dopamine agonist therapy for hyperprolactinaemia: a joint position statement of the British Society of Echocardiography, the British Heart Valve Society and the Society for Endocrinology

This is a joint position statement of the British Society of Echocardiography, the British Heart Valve Society and the Society for Endocrinology on the role of echocardiography in monitoring patients receiving dopamine agonist (DA) therapy for hyperprolactinaemia. (1) Evidence that DA pharmacotherapy causes abnormal valve morphology and dysfunction at doses used in the management of hyperprolactinaemia is extremely limited. Evidence of clinically significant valve pathology is absent, except for isolated case reports around which questions remain. (2) Attributing change in degree of valvular regurgitation, especially in mild and moderate tricuspid regurgitation, to adverse effects of DA in hyperprolactinaemia should be avoided if there are no associated pathological changes in leaflet thickness, restriction or retraction. It must be noted that even where morphological change in leaflet structure and function may be suspected, grading is semi-quantitative on echocardiography and may vary between different machines, ultrasound settings and operators. (3) Decisions regarding discontinuation of medication should only be made after review of serial imaging by an echocardiographer experienced in analysing drug-induced valvulopathy or carcinoid heart disease. (4) A standard transthoracic echocardiogram should be performed before a patient starts DA therapy for hyperprolactinaemia. Repeat transthoracic echocardiography should then be performed at 5 years after starting cabergoline in patients taking a total weekly dose less than or equal to 2 mg. If there has been no change on the 5-year scan, repeat echocardiography could continue at 5-yearly intervals. If a patient is taking more than a total weekly dose of 2 mg, then annual echocardiography is recommended.

Pharmacology of medications used for ovarian stimulation

Medications to stimulate the ovaries may be used to induce ovulation in patients with anovulatory infertility or to hyperstimulate the ovaries in a controlled fashion in ovulatory patients as part of assisted reproductive treatments (ART). The pharmacology of all current major medications used to stimulate ovarian function is reviewed in this article, including letrozole, clomiphene citrate, gonadotropins, and pulsatile gonadotropin releasing hormone (GnRH). Novel potential compounds and adjuvant treatment approaches are also discussed, such as kisspeptin agonists and androgens.

Clinical manifestations, evaluation and management of hyperprolactinemia in adolescent and young girls: a brief review

Hyperprolactinemia (HPrl) is considered as a rare endocrinopathy in childhood. In children and adolescent girls, there are three major categories of HPrl causes; physiological, pathological and iatrogenic. Through hypogonadotropic hypogonadism, prolactin hypersecretion and production leads to the typical functional syndrome which is observed in female children and adolescents; delayed puberty, primary or secondary amenorrhea and/or galactorrhea. Regarding prolactinomas, clinical signs manifest with mass compression of the optic chiasm and anterior pituitary gland or prolactin hypersecretion. Targeted identification of HPrl is of significant importance for proper management and follow-up. The aim of this review is to focus on the evaluation of HPrl in adolescent and young girls. In addition, we aimed to summarize the current knowledge regarding the proper management of such cases. (www.actabiomedica.it)

Three Novel MEN1 Variants in AIP-Negative Familial Isolated Pituitary Adenoma Patients

OBJECTIVES

Pituitary adenomas (PAs) may rarely occur in well-defined hereditary conditions, like multiple endocrine neoplasia type 1 (MEN1) syndrome and familial isolated pituitary adenoma (FIPA) associated with germline mutations in MEN1 and AIP, respectively. This study aimed to assess MEN1 genetic abnormalities in AIP mutation-negative FIPA patients, not associated with MEN1 components.

METHODS

Among 20 patients evaluated in 13 FIPA families, 12 were previously reported as AIP mutation-negative. In this study, 6 new families with 8 patients were recruited. All patients were subjected to multiplex ligation-dependent probe amplification to detect copy number variations in AIP and MEN1, and AIP sequencing was performed in additional patients. AIP mutation-negative patients were subjected to MEN1 sequencing.

RESULTS

Our cohort revealed only 3 novel heterozygous MEN1 variants including c.1846T>A p.(*616Argext*21), rs778272737:T>C, and rs972128957:C>T in 2 families, with patients diagnosed with Cushing disease, nonfunction al adenoma, and acromegaly, respectively. Among them, c.1846T>A p. (*616Argext*21) is a stop codon read-through, whereas the others are 3'UTR variations. MEN1 variation frequency was detected as 15%.

CONCLUSIONS

MEN1 alterations can be of significance in FIPA patients and screening could be offered to AIP mutation-negative patients without MEN1 features. Further studies are needed to clarify the role of MEN1 in FIPA patients.

Causes and Metabolic Consequences of Gynecomastia in Adult Patients

BACKGROUND

Gynecomastia (GM) is a benign enlargement of male breast due to glandular tissue proliferation. GM is a symptom of systemic or local hormonal disturbances, which could be associated with functional changes or pathological conditions. However, the long-lasting steroid imbalance in men with GM might exert negative influence on their metabolic health.

METHODS

A total of 110 adult men with symptomatic GM were included in the present retrospective cross-sectional study. Anthropometric, metabolic, and hormonal data of the patients were collected.

RESULTS

In almost 64% of GM patients, the underlying pathological condition was identified. Moreover, the development of GM was among the primary symptoms leading to the proper diagnosis in more than 40% of hypogonadal patients. The prevalence of metabolic syndrome (MS) was 53%; the highest prevalence of MS was found in patients with medication-induced GM and in the hypogonadal patients, whereas the lowest prevalence was observed in men with idiopathic postpubertal GM despite the similar degree of obesity. The lower testosterone levels were associated with more unfavorable lipid profile in the GM patients.

CONCLUSION

The development of GM in adults might be an important symptom of an underlying gonadal disease. Moreover, it could be associated with an increased risk of metabolic disturbances. Our results support the need of detailed laboratory and hormonal investigations in patients with GM including targeted screening for metabolic disturbances. Further longitudinal studies are needed to evaluate the long-term consequences of sex hormones imbalance on cardiovascular morbidity and mortality in adults with GM.

Surgery for Prolactinomas to Date

While in the past surgery for prolactinomas was a competitive option to medical treatment with dopamine agonists, to date the indications for operations are restricted to only a few specific situations. However, if a patient is intolerant to medical treatment or if the drugs are not sufficiently effective in terms of lowering prolactin levels or tumor shrinkage, surgery should always be considered. In microprolactinomas, operations can achieve excellent prolactin normalization rates. In tumors difficult to treat, the combination of surgical tumor resection and long-term medical treatment supports better control of the disease. The individual indications, results, techniques, and complications of operations for prolactinomas are briefly reviewed in this paper.

MANAGEMENT OF ENDOCRINE DISEASE: Impulse control disorders in patients with hyperpolactinemia treated with dopamine agonists: how much should we worry?

Dopamine agonists (DAs) represent a cornerstone in the management of patients with hyperprolactinemia and have an important role in the treatment of neurologic disorders, including Parkinson's disease and restless legs syndrome. A growing body of evidence has identified impulse control disorders (ICDs) as possible adverse effects of DA therapy. A variety of ICDs may occur in patients treated with DA, including compulsive shopping, pathologic gambling, stealing, hypersexuality and punding (repetitive performance of tasks, such as collecting, sorting, disassembling and assembling objects). These behaviors can have devastating effects on patients' life and family. In the present review article, we summarize available data on ICDs in patients with hyperprolactinemia as well as other disorders. Possible risk factors for the emergence of ICDs in patients treated with DA are discussed and the putative pathophysiologic mechanisms underlying the development of ICDs in this setting are reviewed. In addition, strategies for the early identification and management of ICDs in patients on DA are discussed. In conclusion, a wide variety of ICDs can occur in patients treated with DA, including those with hyperprolactinemia. The development of ICDs can have serious implications for patients' well-being and family. Endocrinologists and other physicians involved in the care of patients on DA therapy must be aware of this potential adverse effect, counsel patients regarding pertinent symptoms and regularly evaluate treated patients for the development of ICDs. Early detection of ICDs and discontinuation of DA therapy can mitigate the potential harms associated with ICDs in these patients.

Screening of AIP Gene Variations in a Cohort of Turkish Patients with Young-Onset Sporadic Hormone-Secreting Pituitary Adenomas

Aims: Aryl hydrocarbon receptor-interacting protein (AIP) gene mutations have long been associated with apparently sporadic pituitary adenomas (PAs) with a prevalence range of 0-12%. The aim of this study was to evaluate the frequency of germline AIP variations in a large cohort of apparently sporadic PAs diagnosed before the age of 40 years, who did not exhibit hypercalcemia and/or MEN1 syndrome components during long-term follow-up. Materials and Methods: A total of 97 patients, diagnosed with functional PAs ≤40 years old, composed of somatotropinoma (n = 55), prolactinoma (n = 25), and corticotrophinoma (n = 17), were recruited for this study. Fifty-one of these patients [somatotropinoma (n = 30), prolactinoma (n = 15), and corticotrophinoma (n = 11)] were previously reported as AIP mutation-negative by Sanger sequencing. The entire coding sequence of the AIP gene, along with exon/intron boundaries and the untranslated regions of 41 newly recruited patients, were sequenced for germline variations. In addition, all patients were subjected to multiplex ligation-dependent probe amplification to detect copy number variations in the AIP gene. Results: The AIP c.911G>A: p.Arg304Gln (rs104894190) variant was detected in only two patients with functional PA: one with somatotropinoma [in 1/55 (1.8%)] and one with prolactinoma [in 1/25 (4%)]. None of the corticotrophinomas revealed AIP gene alterations. Thus, the overall prevalence of AIP variation was 2.1% in our cohort. Conclusions: Germline AIP gene variations among Turkish patients with apparently sporadic PAs are relatively rare among patients ≤40 years old. None of the patients in our cohort revealed any obviously pathogenic AIP variants.

Pediatric pituitary adenomas in Northeast Mexico. A follow-up study

PURPOSE

To review incidence, treatment and outcome of pediatric pituitary adenomas (PAs).

METHODS

A follow-up study patients with the age of ≤19 years old who were treated from 1995 to 2015 in Mexico.

RESULTS

Out of 1244 diagnosed PA, 43 patients were children (35 females, 8 males) with a mean age of 17.2 years. The majority were macroadenomas (70%) with prolactinomas (PRL) dominating (63%) followed by non-functioning adenomas (21%). In total, 40% were diagnosed as invasive. Growth hormone (GH) secreting adenomas, adrenocorticotropic hormone secreting and mixed GH-PRL secreting were rare. The treatment modalities were dopamine agonists and surgery. The average treatment time was 44 months with an average follow-up period of 104 months. Sixty-eight percent (27/40) of the patients had complete response after long time follow-up. Thirty-one percent did not respond to treatment whereof three patients died due to advanced disease and late intervention. The principal causes for treatment failure were treatment resistance, late intervention and poor patient compliance.

CONCLUSIONS

Sixty eight percent had complete treatment response without any sign of disease, while ~31% did not respond to treatment or did not comply to follow up/treatment. Optimized early diagnose, treatment methods with early intervention, long time follow-up and with better measures for patient compliance should improve outcomes.

Repurposing of Bromocriptine for Cancer Therapy

Bromocriptine is an ergot alkaloid and dopamine D₂ receptor agonist used to treat Parkinson's disease, acromegaly, hyperprolactinemia, and galactorrhea, and more recently diabetes mellitus. The drug is also active against pituitary hormone-dependent tumors (prolactinomas and growth-hormone producing adenomas). We investigated, whether bromocriptine also inhibits hormone-independent and multidrug-resistant (MDR) tumors. We found that bromocriptine was cytotoxic towards drug-sensitive CCRF-CEM, multidrug-resistant CEM/ADR5000 leukemic cells as well as wild-type or multidrug-resistant ABCB5-transfected HEK293 cell lines, but not sensitive or BCRP-transfected multidrug-resistant MDA-MB-231 breast cancer cells. Bromocriptine strongly bound to NF-κB pathway proteins as shown by molecular docking and interacted more strongly with DNA-bound NF-κB than free NF-κB, indicating that bromocriptine may inhibit NF-κB binding to DNA. Furthermore, bromocriptine decreased NF-κB activity by a SEAP-driven NF-κB reporter cell assay. The expression of MDR-conferring ABC-transporters (ABCB1, ABCB5, ABCC1, and ABCG2) and other resistance-mediating factors (EGFR, mutated TP53, and IκB) did not correlate with cellular response to bromocriptine in a panel of 60 NCI cell lines. There was no correlation between cellular response to bromocriptine and anticancer drugs usually involved in MDR (e.g., anthracyclines, Vinca alkaloids, taxanes, epipodophyllotoxins, and others). COMPARE analysis of microarray-based mRNA expression in these cell lines revealed that genes from various functional groups such as ribosomal proteins, transcription, translation, DNA repair, DNA damage, protein folding, mitochondrial respiratory chain, and chemokines correlated with cellular response to bromocriptine. Our results indicate that bromocriptine inhibited drug-resistant tumor cells with different resistance mechanisms in a hormone-independent manner. As refractory and otherwise drug-resistant tumors represent a major challenge to successful cancer chemotherapy, bromocriptine may be considered for repurposing in cancer therapy.

Clinical outcomes in male patients with lactotroph adenomas who required pituitary surgery: a retrospective single center study

PURPOSE

Lactotroph adenomas (LA) are the most frequently encountered pituitary tumors. Although more frequently observed in women, LAs in men were recently included in a more aggressive category regardless of histological grading, by the WHO. We aimed to perform a rigorous retrospective review of a single center's pre-operative evaluation, patient characteristics and outcomes of male LAs patients requiring pituitary surgery.

METHODS

A retrospective review, over 11 years, of patients who underwent resection of a pituitary adenoma at a single center was conducted. Predictors of persistent disease in male LAs patients along with a comparison to predictors of silent corticotroph adenomas (SCAs) patients who also underwent surgery at the center was also conducted.

RESULTS

Thirty-one male patients with LAs were identified. When compared to SCAs patients, LAs male patients were younger (41 vs. 50 years of age, p = 0.01). Men with LAs had more invasive tumors (75% vs. 44.7% p = 0.02). More LAs in men had residual tumor after surgery than patients with SCA (92.6% vs. 42.1%, p < 0.001). Male patients with LAs and patients with SCA had similar rates of requiring additional surgery (28.9% vs. 24.1%, p = NS) and radiation therapy (18.4% vs. 19.4%, p = NS).

CONCLUSIONS

High rates of DA resistance, invasive tumors and postoperative residual disease in male patients with LA who required surgery are shown. Surgery improved optic chiasm compression, PRL level and central hypogonadism but, not surprisingly, failed to normalize other pituitary hormones and/or eliminate need for DA therapy.

Ept7, a quantitative trait locus that controls estrogen-induced pituitary lactotroph hyperplasia in rat, is orthologous to a locus in humans that has been associated with numerous cancer types and common diseases

Pituitary adenoma is a common intracranial neoplasm that is observed in approximately 10% of unselected individuals at autopsy. Prolactin-producing adenomas, i.e., prolactinomas, comprise approximately 50% of all pituitary adenomas and represent the most common class of pituitary tumor. Multiple observations suggest that estrogens may contribute to development of prolactinoma; however, direct evidence for a causal role of estrogens in prolactinoma etiology is lacking. Rat models of estrogen-induced prolactinoma have been utilized extensively to identify the factors, pathways and processes that are involved in pituitary tumor development. The objective of this study was to localize to high resolution Ept7 (Estrogen-induced pituitary tumor), a quantitative trait locus (QTL) that controls lactotroph responsiveness to estrogens and was mapped to rat chromosome 7 (RNO7) in an intercross between BN and ACI rats. Data presented and discussed herein localize the Ept7 causal variant(s) to a 1.91 Mb interval of RNO7 that contains two protein coding genes, A1bg and Myc, and Pvt1, which yields multiple non-protein coding transcripts of unknown function. The Ept7 orthologous region in humans is located at 8q24.21 and has been linked in genome wide association studies to risk of 8 distinct epithelial cancers, including breast, ovarian, and endometrial cancers; 3 distinct types of B cell lymphoma; multiple inflammatory and autoimmune diseases; and orofacial cleft defects. In addition, the Ept7 locus in humans has been associated with variation in normal hematologic and development phenotypes, including height. Functional characterization of Ept7 should ultimately enhance our understanding of the genetic etiology of prolactinoma and these other diseases.

Effective long-term temozolomide rechallenge in a macroprolactinoma

We describe the 20-year course of a 63-year-old male with a macroprolactinoma that acquired resistance to treatment and aggressive behavior after a 4-year successful treatment with cabergoline. He was submitted to multiple surgical resections by a skilled surgeon, fractionated radiotherapy and was eventually treated with temozolomide. After a first 6-month standard cycle, a relapse occurred and he was treated again successfully.

Clinical Features and Response to Treatment of Prolactinomas in Children and Adolescents: A Retrospective Single-Centre Analysis and Review of the Literature

BACKGROUND

Paediatric prolactinomas are rare. The aim of this study was to investigate the clinical features and outcome of paediatric patients with prolactinomas.

METHODS

In this single-centre retrospective analysis, clinical, biochemical, and radiological features of all paediatric patients with pituitary adenomas diagnosed between 2000 and 2016 were evaluated.

RESULTS

Among 21 patients with pituitary adenomas, 12 patients with prolactinomas (median age 14.2 years, range 11-16.6 years, 8 females, 4 males) were identified (7 macro- and 5 microprolactinomas). The most common clinical symptoms were headaches (67%) and pubertal delay (67%). All patients with macroprolactinomas with prolactin concentrations >10,000 mU/L had at least 1 pituitary hormone deficiency. Cabergoline as first-line treatment (n = 11, median follow-up of 37 months, range 12-89 months) induced normoprolactinemia (n = 8), reduced the mean tumour volume by 80%, and ameliorated headaches (p = 0.016) and pubertal delay (p = 0.031), whereas intermittent moderate side effects occurred in 55%.

CONCLUSION

Adolescents with headaches and pubertal delay should be investigated for prolactinomas. Treatment with cabergoline is well tolerated and effective in reducing clinical symptoms and prolactin concentrations was well as inducing tumour shrinkage. Further clinical prospective studies are needed to standardize paediatric treatment modalities.

Neurosurgical anesthesia for a pregnant woman with macroprolactinoma: A case report

RATIONALE

Being required to perform neurosurgery on a pregnant woman is rare, but occasionally unavoidable. In these cases, clinical anesthesiologists are confronted with conflicting information and few evidence-based guidelines.

PATIENT CONCERNS

Here, we describe the successful anesthetic management of a 24-week pregnant woman with macroprolactinoma who underwent endonasal transsphenoidal resection of pituitary adenoma.

DIAGNOSES

According to the prolactin (PRL) level and magnetic resonance imaging (MRI) results, the patient was diagnosed with macroprolactinoma and kept stable after taking the regular bromocriptine treatment. However, after stopping the drug by herself because of pregnancy, her tumor increased in size and she suffered from vision loss. Surgery was recommended as soon as possible to lessen the compression in the eye. However, the anesthetic management was a considerable risk due to the increased chance of maternal mortality, intrauterine growth restriction, or preterm labor.

INTERVENTIONS

We held a multidisciplinary meeting before the operation and made a detailed plan for how to proceed. During the operation, our team ensured intensive monitoring, provided adequate oxygen, and achieved haemodynamic stability. Anesthetics like sufentanyl, rocuronium, propofol, and desflurane were carefully chosen in order to ensure the safety of both the mother and fetus.

OUTCOMES

Under the careful and successful anesthetic management, the pregnant woman underwent the surgery smoothly and neither the mother nor baby experienced any pre- or postoperative complications. At the 38th week of gestation, the patient received a cesarean section and the baby had developed normally.

LESSONS

Neurosurgeries in pregnancy are sparse, and careful planning with cross-disciplinary specialists was needed in advance of the operation. Moreover, when dealing with such surgeries, we should consider the safety of both the mother and fetus, which is challenging but important.

Estrogen receptor antagonist fulvestrant inhibits proliferation and promotes apoptosis of prolactinoma cells by regulating the IRE1/XBP1 signaling pathway

The aim of the present study was to evaluate the effects of an estrogen receptor antagonist, fulvestrant, on proliferation and apoptosis of prolactinoma cells, and to reveal potential regulatory mechanisms. Prolactinoma GH3 cells were treated with 10‑6 mol/l fulvestrant for 2, 4, 8, 12 and 24 h. GH3 cell growth was observed under a microscope and cell viability was detected by MTT assay. Morphological changes of the nuclei in GH3 cells were observed by Hoechst 33258 staining and apoptotic rates were detected by flow cytometry. Preprolactin (PPL) and prolactin (PRL) secretion levels from GH3 cells were measured using ELISA. In addition, the protein expression levels of inositol‑requiring enzyme 1 (IRE1), X‑box binding protein (XBP)‑1 and glucose‑regulated protein, 78 kDa (GRP78) in GH3 cells were detected by western blot analysis. Cell density and cell viability of GH3 cells were significantly reduced in a time‑dependent manner following treatment with fulvestrant (P<0.05). GH3 cells treated with fulvestrant also acquired an apoptotic morphology and the apoptotic rate of GH3 cells was significantly increased by fulvestrant in a time‑dependent manner (P<0.05). PPL and PRL secretion levels were significantly reduced by fulvestrant treatment in a time‑dependent manner (P<0.05). The protein expression levels of IRE1, XBP1 and GRP78 were also significantly reduced in a time‑dependent manner following treatment with fulvestrant (P<0.05). Therefore, fulvestrant may inhibit proliferation and promote apoptosis of GH3 cells by downregulating the IRE1/XBP1 signaling pathway.

IGF-1 levels may increase paradoxically with dopamine agonist treatment for prolactinomas

OBJECTIVE

Hyperprolactinemia is common in acromegaly and in these patients, insulin-like growth factor (IGF)-1 level may decrease with dopamine agonist. We report a series of patients with prolactinoma and a paradoxical increase of IGF-1 levels during cabergoline treatment.

METHODS

Clinical characteristics and response to treatment of patients with prolactinomas, in whom normal or slightly elevated baseline IGF-1 levels increased with cabergoline.

RESULTS

The cohort consisted of ten prolactinoma patients (nine males, mean age 48 ± 14 years). Mean adenoma size was 23.8 ± 16.2 mm, with cavernous sinus invasion in eight. In five patients baseline IGF-1 levels were normal and in four levels were 1.2-1.5-fold the upper limit of the normal (ULN). One patient had IGF-1 measured shortly after initiating cabergoline and it was 1.4 × ULN. During cabergoline treatment (dose range 0.5-2 mg/week) PRL normalization was achieved in all and tumor shrinkage occurred in seven patients. The mean IGF-1 increase on cabergoline was 1.7 ± 0.4 × ULN. Cabergoline dose reduction or interruption was attempted in five patients and resulted in decreased IGF-1 levels in all, including normalization in two patients. Three patients were eventually diagnosed with acromegaly, one was referred for pituitary surgery followed by complete remission, another patient was switched to somatostatin analogue, and the third was treated by combination of somatostatin analogues with pegvisomant, with reduction of IGF-1 in all these patients.

CONCLUSION

IGF-1 levels may increase to clinically significant levels during cabergoline treatment for PRL-adenoma. We suggest IGF-1 monitoring in all patients treated with dopamine agonists and not only in those presenting symptoms of acromegaly.