Metabolic and inflammatory parameters in relation to baseline characterization and treatment outcome in patients with prolactinoma: insights from a retrospective cohort study at a single tertiary center.

Background: Prolactinomas (PRLs) are prevalent pituitary adenomas associated with metabolic changes and increased cardiovascular morbidity. This study examined clinical, endocrine, metabolic, and inflammatory profiles in PRL patients, aiming to identify potential prognostic markers. Methods: The study comprised data from 59 PRL patients gathered in a registry at the University Hospital of Zurich. Diagnostic criteria included MRI findings and elevated serum prolactin levels. We assessed baseline and follow-up clinical demographics, metabolic markers, serum inflammation-based scores, and endocrine parameters. Treatment outcomes were evaluated based on prolactin normalization, tumor shrinkage, and cabergoline dosage. Results: The PRL cohort exhibited a higher prevalence of overweight/obesity, prediabetes/diabetes mellitus, and dyslipidemia compared to the general population. Significant correlations were found between PRL characteristics and BMI, HbA1c, and fT4 levels. Follow-up data indicated decreases in tumor size, tumor volume, prolactin levels, and LDL-cholesterol, alongside increases in fT4 and sex hormones levels. No significant associations were observed between baseline parameters and tumor shrinkage at follow-up. A positive association was noted between PRL size/volume and the time to achieve prolactin normalization, and a negative association with baseline fT4 levels. Conclusion: This study underscores the metabolic significance of PRL, with notable correlations between PRL parameters and metabolic indices. However, inflammatory markers were not significantly correlated with patient stratification or outcome prediction. These findings highlight the necessity for standardized follow-up protocols and further research into the metabolic pathogenesis in PRL patients.

Reconsideration of Surgical Indication for Prolactin-producing Pituitary Tumor Focusing on Visual Impairment.

Prolactin-producing pituitary tumor (PRLoma) is the most prevalent functional pituitary tumor. If the tumor becomes large, vision can be impaired. In contrast to other pituitary tumors, cabergoline (CAB) is extremely effective for PRLoma and has become the first-line treatment. In this study, we examined our experience with the pharmacological and surgical management of PRLomas with visual impairment (VI) to determine whether VI could be a surgical indication. Further, we discussed the function of surgery in situations where the gold standard of PRLoma treatment was CAB administration. Of the 159 patients with PRLomas (age, 13-77 [mean = 36.3] years; men, 29; women, 130) at Tokyo Women's Medical University Hospital from 2009 to 2021, 18 (age, 15-67 [mean = 35.8] years; men, 12; woman, 6) had VI (subjectively, 12; objectively, 6). They started CAB treatment immediately (maximum dose: 0.5 to 6 mg/week; average: 2.17 mg/week). VI improved in 16 patients (88.9%) but did not improve in 2 (11.1%) requiring surgeries. One of the two patients had a parenchymal tumor resistant to CAB, and the other had a cystic tumor due to intratumoral bleeding. Consequently, CAB is the first-line treatment for PRLomas with VI because of its significantly high rate of improvement. However, close and rigorous surveillance is necessary for cases resistant to CAB, and the correct decision is required regarding surgical interventions at proper timing and appropriate surgical approaches considering the purpose of surgery.

Prolactinoma in postmenopausal women: a systematic review.

IMPORTANCE: Prolactinomas occurring during the reproductive period exhibit a characteristic behavior. There are, however, gaps in the literature regarding the behavior of these tumors after menopause. OBJECTIVE: This study aimed to review and characterize the influence of menopause on prolactinoma behavior. EVIDENCE REVIEW: A systematic review of observational prospective or retrospective studies and clinical trials on prolactinomas was conducted in two situations: tumors diagnosed in the reproductive period (before menopause), with follow-up in the postmenopausal period, or prolactinomas diagnosed in the postmenopausal period, without language or date restrictions. Data extracted from the articles included patient and tumor characteristics (prolactinoma type, previous treatment, symptoms, and serum prolactin [PRL] levels). FINDINGS: This study included five studies comprising 180 participants. Prolactinomas diagnosed in women of reproductive age are treated with dopaminergic agonists (DAs), with indications of treatment withdrawal after menopause, exhibited stable tumor behavior and PRL levels. Considering the diagnosis during the postmenopausal period, macroprolactinomas were more prevalent and showed tumor shrinkage when DAs were used. Cabergoline, the most commonly used drug, lowers PRL levels and reduces symptoms associated with adenoma. CONCLUSIONS AND RELEVANCE: Microadenomas diagnosed before menopause can be followed up without treatment. Prolactinomas diagnosed after menopause are typically macroadenomas. Cabergoline remains the treatment of choice in the presence of clinical or compressive symptoms. We recommend at least one annual follow-up for such patients.

Cabergoline treatment for surgery-naïve non-functioning pituitary macroadenomas.

PURPOSE: The treatment strategy of non-functioning pituitary adenomas (NFPAs) includes surgery, radiotherapy, medical therapy, or observation without intervention. Cabergoline, a dopaminergic agonist, was suggested for the treatment of NFPA remnants after trans-sphenoidal surgery. This study investigates the efficacy of cabergoline in surgery-naive patients with NFPA. METHODS: Retrospective cohort study including surgery-naive patients with NFPA ≥ 10 mm, treated with cabergoline at a dose of ≥ 1 mg/week for at least 24 months. Patients with chiasmal damage were excluded. Data collected included symptoms, in particular visual disturbances, hormonal levels, tumor characteristics and size evaluated by MRI. Tumor growth was defined as an increase in maximal diameter of ≥ 2 mm, and shrinkage as reduction of ≥ 2 mm. RESULTS: Our cohort included 25 patients treated with cabergoline as primary therapy. Mean age was 63.3 ± 17.3 years, 56% (14/25) were males. Mean tumor size at diagnosis was 18.6 ± 6.3 mm (median 17 mm, range 10-36), and the average follow-up period with cabergoline was 4.6 ± 3.4 years. Out of the 25 tumors, five tumors (20%) decreased in size (mean decrease of 5.0 ± 3.0 mm), 12 tumors (48%) remained stable, and eight (32%) increased in size (mean growth of 5.0 ± 3.3 mm) with cabergoline treatment. During the first two years of cabergoline treatment, the median tumor size exhibited a reduction of 0.5 mm. Patients with an increase in tumor size had larger adenomas at diagnosis and a longer follow-up. Two patients (8%) underwent surgery due to tumor enlargement. CONCLUSION: Primary treatment with cabergoline is a reasonable approach for selected patients with NFPAs without visual threat.

Aflibercept suppresses ovarian hyperstimulation syndrome: an experimental study in rats.

OBJECTIVE: In this study, we aimed to determine the impact of the antiangiogenic medications, namely, aflibercept and cabergoline in the prevention and treatment of ovarian hyperstimulation syndrome in a rat model. METHODS: A total of 36 female Wistar rats were randomly allocated to one of the five groups, including disease-free and ovarian hyperstimulation syndrome controls: Group no OHSS (control, n=6) received saline only intraperitoneally (i.p.); group just OHSS (ovarian hyperstimulation syndrome only, n=6) received 10 IU pregnant mare serum gonadotropin and 30 IU human chorionic gonadotropin subcutaneously to produce ovarian hyperstimulation syndrome; group cabergoline+OHSS (cabergoline+ovarian hyperstimulation syndrome, n=8) received 100 µg/kg oral cabergoline; group aflibercept (12.5 mg/kg)+OHSS (aflibercept+ovarian hyperstimulation syndrome, n=8) received 12.5 mg/kg i.p. aflibercept; and group aflibercept (25 mg/kg)+OHSS (aflibercept+ovarian hyperstimulation syndrome, n=8) received 25 mg/kg i.p. aflibercept. The groups were compared for ovarian weight, immunohistochemical vascular endothelial growth factor expression, spectrophotometric vascular permeability evaluated with methylene blue solution in peritoneal lavage, and body weight growth. RESULTS: Vascular endothelial growth factor immunoexpression was substantially greater in the just OHSS group (22.00±10.20%) than in the aflibercept (12.5 mg/kg)+OHSS (7.87±6.13%) and aflibercept (25 mg/kg)+OHSS (5.63±4.53%) groups (p=0.008 and p=0.005, respectively). Post-hoc tests indicated that cabergoline, 12.5 mg/kg aflibercept, and 25 mg/kg aflibercept decreased vascular permeability compared to the untreated ovarian hyperstimulation syndrome group (p=0.003, p=0.003, and p=0.001, respectively). JOH group had the heaviest ovaries, whereas aflibercept (25 mg/kg)+OHSS group had the lightest. In terms of body weight gain, cabergoline+OHSS group was substantially greater than the aflibercept (12.5 mg/kg)+OHSS and aflibercept (25 mg/kg)+OHSS groups (p=0.006 and p=0.007, respectively). CONCLUSION: Aflibercept, an antiangiogenic medication, decreased ovarian hyperstimulation syndrome by lowering the vascular permeability and vascular endothelial growth factor expression.

Late-onset symptomatic hyperprolactinemia in 6-pyruvoyl-tetrahydropterin synthase deficiency.

BACKGROUND: Tetrahydrobiopterin (BH4) deficiency caused by 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency is a rare disorder that is one of the major causes of hyperphenylalaninemia in Taiwan. METHODS: In this study, we reviewed the clinical courses of 12 adolescent and adult patients (7 females and 5 males) with PTPS deficiency. RESULTS: The patients were treated shortly after diagnosis through newborn screening with a combination of BH4, levodopa/carbidopa, and 5-OH-tryptophan. Their plasma phenylalanine and tyrosine levels were well controlled, and their prolactin levels were also decreased after treatment. However, their prolactin levels gradually rose as they grew into puberty, and at a current age of 27.5 [interquartile range (IQR 7.9)] years, five of the 12 patients had either highly elevated prolactin levels (> 100 ng/mL in one male patient, normal reference values, male < 11 ng/mL, female < 17 ng/mL) or symptoms, including irregular menstruation, amenorrhea, and breast swelling (in four female patients). The dosage of levodopa in these five patients (14.3 (IQR 3.0) mg/kg/day) was slightly higher than that in the other patients (p = 0.05). Magnetic resonance imaging studies did not reveal an increase in the size of the anterior pituitary gland, although a Rathke cleft cyst was found in one patient. Two patients received cabergoline treatment, which promptly lowered prolactin levels and relieved symptoms. CONCLUSIONS: Hyperprolactinemia is common in female patients with PTPS deficiency, especially after puberty. A long-acting dopamine agonist, such as cabergoline, may be a necessary adjunctive treatment for most patients with BH4 deficiency.

Long-term efficacy and safety of subcutaneous pasireotide alone or in combination with cabergoline in Cushing's disease.

Objective: This study evaluated short- and long-term efficacy and safety of the second-generation somatostatin receptor ligand pasireotide alone or in combination with dopamine agonist cabergoline in patients with Cushing's disease (CD). Study design: This is an open-label, multicenter, non-comparative, Phase II study comprising 35-week core phase and an optional extension phase. All patients started with pasireotide, and cabergoline was added if cortisol remained elevated. Eligible patients had active CD, with or without prior surgery, were pasireotide naïve at screening or had discontinued pasireotide for reasons other than safety. Primary endpoint was proportion of patients with a mean urinary free cortisol (mUFC) level not exceeding the upper limit of normal (ULN) at week 35 with missing data imputed using last available post-baseline assessments. Results: Of 68 patients enrolled, 26 (38.2%) received pasireotide monotherapy and 42 (61.8%) received pasireotide plus cabergoline during the core phase. Thirty-four patients (50.0%; 95% CI 37.6-62.4) achieved the primary endpoint, of whom 17 (50.0%) received pasireotide monotherapy and 17 (50.0%) received combination therapy. Proportion of patients with mUFC control remained stable during the extension phase up to week 99. Treatment with either mono or combination therapy provided sustained improvements in clinical symptoms of hypercortisolism up to week 99. Hyperglycemia and nausea (51.5% each), diarrhea (44.1%) and cholelithiasis (33.8%) were the most frequent adverse events. Conclusion: Addition of cabergoline in patients with persistently elevated mUFC on maximum tolerated doses of pasireotide is an effective and well-tolerated long-term strategy for enhancing control of hypercortisolism in some CD patients. Clinical trial registration: https://clinicaltrials.gov/ct2/show/NCT01915303, identifier NCT01915303.

Prolactinomas Resistant to Dopamine Agonists: Pathophysiology and Treatment.

Prolactinomas are the most common functional pituitary tumors, accounting for 40% of all pituitary adenomas. Medical treatment with dopamine agonists (DA), mainly cabergoline, is considered the primary therapy for these patients. Prolactin normalization is achieved in 80-90% of prolactinomas treated with cabergoline. Patients resistant to the standard dose can escalate the dose of cabergoline up to the maximum tolerated dose. The expression of dopamine (D2) receptors and dopamine affinity is decreased in aggressive and resistant prolactinomas. Patients with aggressive and DA-resistant adenomas or with rare PRL-secreting carcinomas can be treated off-label with temozolomide (TMZ), a DNA alkylating agent. TMZ is effective in 40-50% of treated lactotroph tumors showing at least a partial response. However, patients tend to escape from the effect of TMZ after a limited time of response. Other therapeutic options include aromatase inhibitors, the somatostatin receptor ligand pasireotide, peptide receptor radionuclide therapy (PRRT), immune-checkpoint inhibitors, tyrosine-kinase inhibitors, or everolimus, the mammalian target of rapamycin inhibitor. These experimental treatments were effective in some patients carrying refractory prolactinomas showing usually partial tumor control. However, the number of treated patients with any of these new therapeutic options is very limited and treatment results are inconsistent, thus additional experience with more patients is required.

Syndrome of inappropriate antidiuretic hormone with recurrent giant cabergoline-resistant prolactinoma.

A macro pituitary tumour or giant pituitary tumour is regarded as a rare causal factor in syndrome of inappropriate antidiuretic hormone (SIADH) cases. Previous reports have presented findings showing that blood flow insufficiency related to stress caused by an obstructive mass may lead to inappropriate secretion of arginine vasopressin. On the other hand, prolactin is known to influence water metabolism, and several cases of a macroprolactinoma or giant prolactinoma (PRLoma) in patients with SIADH have been reported. Nevertheless, few studies have examined such a relationship with SIADH and discussion of pathophysiological factors has been limited. The present report provides details of an elderly patient with SIADH in a chronic giant PRLoma. Of note, exacerbation of prolactin level accompanied the occurrence of SIADH. Findings obtained in this case suggest the possibility of development of SIADH in PRLoma cases due to more than only the effect of the mass.

Risk of impulse control disorders in patients with Cushing's disease: do not blame cabergoline but do not give up caution.

PURPOSE: To asses risk of new-onset impulse control disorders (ICDs) in patients with Cushing's disease (CD) who initiated cabergoline (CBG) and to determine frequency of ICDs in CBG-treated patients with CD. METHODS: This naturalistic observational study had prospective and cross-sectional arms which included patients at five referral centers based in Istanbul. Patients who were scheduled for CBG were assigned to prospective arm. These patients underwent neuropsychological tests (Barratt Impulsiveness Scale, Minnesota Impulsive Disorders Interview, Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease-Rating Scale, Go/No-Go Task, Iowa Gambling Task, and Short Penn Continuous Performance Test) for assessment of impulsivity and psychiatric evaluations at baseline, 3, 6, and 12 months of CBG treatment. Impulsivity and new-onset ICDs were prospectively assessed. Patients with CD with current CBG treatment for ≥ 3 months and matched CBG-naïve patients with CD were included in cross-sectional arm. These patients underwent the same neuropsychological and psychiatric assessments. The impulsivity and frequency of ICDs were compared between CBG-treated and CBG-naïve patients with CD. RESULTS: The follow-up duration of prospective cohort (n = 14) was 7.3 ± 2.3 months. One patient developed major depressive episode and another patient developed compulsive gambling after CBG. We observed no significant changes in impulsivity scores during follow-up. In cross-sectional arm, CBG-treated (n = 34) and CBG-naïve patients (n = 34) were similar in impulsivity scores and frequency of ICDs [3 patients (8.8%) vs. 2 patients (5.9%) respectively, p = 1.0]. CONCLUSION: CBG-treated patients with CD appeared to have a low risk of ICDs, suggesting that CBG still holds promise as a safe agent in CD.

Cabergoline for Lactation Inhibition After Second-Trimester Abortion or Pregnancy Loss: A Randomized Controlled Trial.

OBJECTIVE: To assess cabergoline's efficacy at decreasing breast symptoms after second-trimester abortion or pregnancy loss. METHODS: This was a double-blinded, block-randomized superiority trial comparing cabergoline 1 mg once to placebo for preventing bothersome breast engorgement after second-trimester uterine evacuation. We enrolled pregnant people at 18-28 weeks of gestation who were English- or Spanish-speaking and without contraindication to the study drug. Participants completed a validated, piloted, electronic survey at baseline and at multiple timepoints through 2 weeks postprocedure to assess breast symptoms, side effects, and bother. Our primary outcome was any breast symptoms (a composite of engorgement, milk leakage, tenderness, and need for pain relief) on day 4; we planned to enroll 80 patients to show a 30% difference in breast symptoms (80% power, α=0.049). A subgroup of participants returned for serum prolactin levels. RESULTS: After screening 150 patients from April 2021 to June 2022, we enrolled 73 participants. Baseline demographics were balanced between groups: median gestational age was 21 weeks (range 18-26 weeks), 56.2% of participants were nulliparous, 34.2% self-identified as Hispanic, and 37.0% had public insurance. At baseline, reported breast symptoms were similar between groups. Among 69 participants who returned surveys on day 4, significantly fewer participants receiving cabergoline reported any breast symptoms compared with placebo (27.8% vs 97.0%, P<.001) (primary outcome) and fewer reported significant bother (2.8% vs 33.3%, P=.001) (secondary outcome). These differences persisted through day 14. Reported incidence and severity of bother from side effects were similar between groups: most common were constipation, fatigue, and headache. Serum prolactin levels were similar at baseline. On day 4, mean serum prolactin level was 6.5 ng/mL (SD 2.2) for those who received cabergoline and 18.0 ng/mL (SD 5.9) for placebo (P=.049). CONCLUSION: Cabergoline is an effective and well-tolerated strategy to prevent breast symptoms after second-trimester abortion or pregnancy loss. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT04701333.

[Succès de traitement par Cabergoline d'une série de cas de cardiomyopathie du péripartum, incluant un cas critique nécessitant une assistance circulatoire mécanique]. / Successful treatment with Cabergoline in critical peripartum cardiomyopathy patient on Veno-Arterial Extra Corporeal Membrane Oxygenation.

Peripartum cardiomyopathy is a life-threatening condition that requires urgent diagnosis and management. Bromocriptine was established as disease specific therapy; less data is known about Cabergolin which is another prolactin secretion inhibitor. In this paper we report 4 peripartum cardiomyopathy cases treated successfully with Cabergoline, including a cardiogenic shock case requiring mechanical circulatory support.

Italian Guidelines for the Management of Prolactinomas.

INTRODUCTION: This guideline (GL) is aimed at providing a reference for the management of prolactin (PRL)-secreting pituitary adenoma in adults. However, pregnancy is not considered. METHODS: This GL has been developed following the methods described in the Manual of the Italian National Guideline System. For each question, the panel appointed by Associazione Medici Endocrinologi (AME) has identified potentially relevant outcomes, which have then been rated for their impact on therapeutic choices. Only outcomes classified as "critical" and "important" have been considered in the systematic review of evidence and only those classified as "critical" have been considered in the formulation of recommendations. RESULTS: The present GL provides recommendations regarding the role of pharmacological and neurosurgical treatment in the management of prolactinomas. We recommend cabergoline (Cab) vs. bromocriptine (Br) as the firstchoice pharmacological treatment to be employed at the minimal effective dose capable of achieving the regression of the clinical picture. We suggest that medication and surgery are offered as suitable alternative first-line treatments to patients with non-invasive PRL-secreting adenoma, regardless of size. We suggest Br as an alternative drug in patients who are intolerant to Cab and are not candidates for surgery. We recommend pituitary tumor resection in patients 1) without any significant neuro-ophthalmologic improvement within two weeks from the start of Cab, 2) who are resistant or do not tolerate Cab or other dopamine-agonist drugs (DA), 3) who escape from previous efficacy of DA, and 4) who are unwilling to undergo a chronic DA treatment. We recommend that patients with progressive disease notwithstanding previous tumor resection and ongoing DA should be managed by a multidisciplinary team with specific expertise in pituitary diseases using a multimodal approach that includes repeated surgery, radiotherapy, DA, and possibly, the use of temozolomide. CONCLUSION: The present GL is directed to endocrinologists, neurosurgeons, and gynecologists working in hospitals, in territorial services or private practice, and to general practitioners and patients.

Vitamin D Status Determines Cardiometabolic Effects of Cabergoline in Women with Elevated Prolactin Levels: A Pilot Study.

Both hyperprolactinemia and vitamin D deficiency appear to be associated with increased cardiometabolic risk. This study aimed to determine whether vitamin D status influences the cardiometabolic effects of cabergoline. The study included three matched groups of women with mild to moderate hyperprolactinemia: vitamin D-naive subjects with vitamin D insufficiency (group A), women with vitamin D deficiency/insufficiency successfully treated with vitamin D (group B), and vitamin D-naive individuals with normal vitamin D status (group C). Plasma prolactin, 25-hydroxyvitamin D, estradiol, glucose homeostasis markers, lipids, high-sensitivity C-reactive protein (hsCRP), fibrinogen, homocysteine, and uric acid, as well as the urinary albumin-to-creatinine ratio (UACR), were measured at study entry and after four months of cabergoline treatment. Although cabergoline reduced prolactin levels and increased estradiol levels in all study groups, the effect on prolactin was more pronounced in groups B and C compared to group A. In groups B and C, the drug enhanced glucose homeostasis, increased HDL-cholesterol, and decreased triglycerides, hsCRP, fibrinogen, homocysteine, uric acid, and UACR. In group A, only insulin resistance, hsCRP, and homocysteine were reduced by cabergoline. The effects on insulin sensitivity, HDL-cholesterol, triglycerides, hsCRP, fibrinogen, homocysteine, uric acid, and UACR were proportional to the decrease in prolactin and baseline levels of 25-hydroxyvitamin D. The obtained results suggest that vitamin D status determines cabergoline's cardiometabolic effects.

Does cabergoline administration affect endometrial VEGFR-2 expression in a rat model of ovarian hyperstimulation syndrome?

OBJECTIVE: To assess the effect of cabergoline on endometrial vascular endothelial growth factor receptor-2 (VEGFR-2) immunoexpression in an ovarian hyperstimulation syndrome (OHSS) rat model. MATERIAL AND METHODS: Twenty-one immature female Wistar rats were assigned into three groups: group 1, the control group; group 2, stimulated with gonadotropins to mimic OHSS; and group 3, in which an OHSS protocol was induced and thereafter treated with cabergoline (100 µg/kg/day). Body weight, ovarian volume, corpora lutea numbers, and endometrial VEGFR-2 expression were compared between the groups. RESULTS: Weight gain and ovarian volume were highest in the OHSS-placebo group, while cabergoline administration significantly reversed those effects (p = 0.001 and p = 0.001, respectively). VEGFR-2 stained cells were significantly lower in groups 2 and 3 compared to group 1 (p = 0.002). Although VEGFR-2 expression was lowest in group 3, the difference was not statistically significant. Corpora lutea numbers were also similar (p = 0.465). CONCLUSION: While successful implantation requires a vascularized receptive endometrium, impaired expression of VEGFR-2 and disrupted endometrial angiogenesis due to cabergoline administration may be associated with IVF failure in fresh OHSS cycles. The insignificant decrease in endometrial VEGFR-2 expression observed in this research needs to be investigated by further studies involving additional techniques such as immunoblotting and/or RT-PCR analyses.

How to manage intolerance to dopamine agonist in patients with prolactinoma.

PURPOSE: Dopamine agonists (DA) are the gold-standard for prolactinoma and hyperprolactinemia treatment. Intolerance to DA leading to drug drop out occurs in 3 to 12% of cases. We provide here a review of published data about DA intolerance and present a case report concerning the use of intravaginal cabergoline. METHODS: We review the literature on the definition, the pathogenesis, frequency and management of DA intolerance. In addition, the review provides strategies to enhance tolerability and avoid precocious clinical treatment withdrawal. RESULTS: Cabergoline is often cited as the most tolerable DA and its side effects tend to ameliorate within days to weeks. Restarting the same drug at a lower dose or switching to another DA can be used in cases of intolerance. The vaginal route can be tried specifically if there are gastrointestinal side effects in the oral administration. Symptomatic treatment could be attempted, although mainly based on a strategy used in other diseases. CONCLUSIONS: Due to limited data, no guidelines have been developed for the management of intolerance in DA treatment. The most frequent management is to perform transsphenoidal surgery. Nevertheless, this manuscript provides data derived from published literature and expert opinion, suggesting new approaches to this clinical issue.

Autoimmune Thyroiditis Attenuates Cardiometabolic Effects of Cabergoline in Young Women With Hyperprolactinemia.

Both prolactin excess and autoimmune (Hashimoto) thyroiditis may predispose to the development of cardiometabolic disorders. The aim of this study was to investigate whether autoimmune thyroiditis determines cardiometabolic effects of cabergoline. The study population consisted of 2 groups of young women: 32 women with euthyroid Hashimoto thyroiditis (group A) and 32 individuals without thyroid disorders (group B). Both groups were matched for age, body mass index, blood pressure, and prolactin levels. Plasma prolactin, thyroid antibodies, glucose homeostasis markers, plasma lipids, circulating levels of uric acid, high-sensitivity C-reactive protein (hsCRP), fibrinogen and homocysteine, and the urinary albumin-to-creatinine ratio were assessed before and after 6 months of cabergoline treatment. All women completed the study. Both groups differed in thyroid antibody titers, insulin sensitivity, high-density lipoprotein cholesterol, hsCRP, homocysteine, and the albumin-to-creatinine ratio. Although cabergoline treatment reduced prolactin levels, improved insulin sensitivity, decreased glycated hemoglobin, increased high-density lipoprotein cholesterol, decreased hsCRP, and reduced the albumin-to-creatinine ratio in both treatment groups, these effects (except for glycated hemoglobin) were more pronounced in group B than in group A. Only in group B, the drug decreased triglycerides, uric acid, fibrinogen, and homocysteine. In group A, hsCRP levels correlated with both baseline thyroid antibody titers and with other cardiometabolic risk factors. The impact of cabergoline on cardiometabolic risk factors depended on the degree of reduction in prolactin levels, while in group A additionally correlated with the effect of treatment on hsCRP. The obtained results suggest that coexisting autoimmune thyroiditis attenuates cardiometabolic effects of cabergoline in young women with hyperprolactinemia.

Diagnosis and Management of Pituitary Adenomas: A Review.

Importance: Pituitary adenomas are neoplasms of the pituitary adenohypophyseal cell lineage and include functioning tumors, characterized by the secretion of pituitary hormones, and nonfunctioning tumors. Clinically evident pituitary adenomas occur in approximately 1 in 1100 persons. Observations: Pituitary adenomas are classified as either macroadenomas (≥10 mm) (48% of tumors) or microadenomas (<10 mm). Macroadenomas may cause mass effect, such as visual field defects, headache, and/or hypopituitarism, which occur in about 18% to 78%, 17% to 75%, and 34% to 89% of patients, respectively. Thirty percent of pituitary adenomas are nonfunctioning adenomas, which do not produce hormones. Functioning tumors are those that produce an excess of normally produced hormones and include prolactinomas, somatotropinomas, corticotropinomas, and thyrotropinomas, which produce prolactin, growth hormone, corticotropin, and thyrotropin, respectively. Approximately 53% of pituitary adenomas are prolactinomas, which can cause hypogonadism, infertility, and/or galactorrhea. Twelve percent are somatotropinomas, which cause acromegaly in adults and gigantism in children, and 4% are corticotropinomas, which secrete corticotropin autonomously, resulting in hypercortisolemia and Cushing disease. All patients with pituitary tumors require endocrine evaluation for hormone hypersecretion. Patients with macroadenomas additionally require evaluation for hypopituitarism, and patients with tumors compressing the optic chiasm should be referred to an ophthalmologist for formal visual field testing. For those requiring treatment, first-line therapy is usually transsphenoidal pituitary surgery, except for prolactinomas, for which medical therapy, either bromocriptine or cabergoline, is usually first line. Conclusions and Relevance: Clinically manifest pituitary adenomas affect approximately 1 in 1100 people and can be complicated by syndromes of hormone excess as well as visual field defects and hypopituitarism from mass effect in larger tumors. First-line therapy for prolactinomas consists of bromocriptine or cabergoline, and transsphenoidal pituitary surgery is first-line therapy for other pituitary adenomas requiring treatment.

Macroprolactinoma with secondary resistance to dopamine agonists: a case report and review of the literature.

BACKGROUND: Resistance to dopamine agonists is not uncommonly seen in prolactinomas. However, development of resistance to dopamine agonists after an initial period of robust treatment response is rare, and only 39 cases have been reported in the past four decades. We describe a Chinese man with this rare condition and explored the postulated mechanisms that may explain this phenomenon. We compiled similar cases that were previously reported and compared their etiology, progress, and response to treatment. On the basis of these cases, we derived a list of differential diagnoses to consider in patients with secondary resistance to dopamine agonists. CASE PRESENTATION: A 63-year-old Chinese man presented with blurred vision and was subsequently diagnosed with a macroprolactinoma. He had initial response to cabergoline but developed secondary resistance to it after 5 years. The prolactinoma continued to grow, and his serum prolactin remained markedly elevated despite adherence to escalating dosages of cabergoline up to 6 mg/week. The patient finally underwent transsphenoidal surgery and was found to have a sparsely granulated lactotroph tumor with Ki-67 index of 5%. Postoperatively, there was improvement in his serum prolactin level, although he still required treatment with cabergoline at 6 mg/week. CONCLUSIONS: Surgery can facilitate disease control in patients with prolactinomas that develop secondary resistance to dopamine agonists. Malignant prolactinoma is an important differential diagnosis in this group of patients, especially when serum prolactin remains markedly elevated despite resolution or stability of the primary pituitary lesion, suggesting a metastatic source of prolactin secretion.

Approach to the Patient With Prolactinoma.

Prolactinomas are the most common pituitary tumor histotype, with microprolactinomas being prevalent in women and macroprolactinomas in men. Hyperprolactinemia is among the most common causes of hypogonadotropic hypogonadism in both sexes, prompting medical advice for hypogonadism (infertility, oligo-amenorrhea, impotence, osteoporosis/osteopenia) in both sexes, and for signs and symptoms of mass effects (hypopituitarism, visual loss, optic chiasm compression, cranial nerve deficits, headaches) predominantly in men. Diagnostic workup involves a single prolactin measurement and pituitary imaging, but some laboratory artifacts (ie, the "hook effect" and macroprolactin) can complicate or delay the diagnosis. The treatment of choice for prolactinomas is represented by dopamine agonists, mainly cabergoline, which are able to induce disease control, restore fertility in both sexes, and definitively cure one-third of patients, thus permitting treatment discontinuation. Pregnancy and menopause may promote spontaneous prolactin decline and anticipate cabergoline discontinuation in women. Surgery and/or radiotherapy are indicated in case of resistance to cabergoline not overcome by the increase in drug dose up to the maximally tolerated or the patient's personal choice of surgery. The evidence of resistance to cabergoline in invasive and proliferative tumors may indicate biological aggressiveness, thus requiring alternative therapeutic approaches mainly based on temozolomide use as monotherapy or combined with radiotherapy. In uncontrolled patients, new medical approaches (alternative hormonal treatments, cytotoxic drugs, peptide receptor radionuclide therapy, mTOR/Akt inhibitors, tyrosine kinase inhibitors, or immunotherapy) may be offered but the experience collected to date is still very scant. This article reviews different facets of prolactinomas and discusses approaches to the condition in more common clinical situations.