Visual morbidity in macroprolactinoma: A retrospective cohort study.

OBJECTIVE: The management of visual field damage in patients with macroprolactinomas is a major therapeutic challenge. We aimed to study the visual morbidity associated with macroprolactinoma and its outcomes following medical and surgical treatment. We aimed to identify predictors of visual recovery. METHODS: We retrospectively reviewed patient's data including clinical presentation, serial pituitary magnetic resonance imaging, laboratory tests, visual symptoms and neuro-ophthalmologic examination, visual field tests and optical coherence tomography tests. The main outcome was complete visual field recovery. Descriptive analyses were conducted. Predictors of visual recovery were investigated. PATIENTS: The study cohort included 150 patients with macroprolactinoma [median follow-up, 6.0 years (interquartile range (IQR) 2.9-10.6)]. RESULTS: At diagnosis, visual field defects were evident in 40 patients (26.7%). At the end of follow-up, 24 out of 39 available visual field tests (61.5%) exhibited complete recovery. Patients that achieved complete visual recovery had smaller macroadenomas at diagnosis [30.5 mm (15.0-80.0) vs. 42.0 mm (30.0-85.0), p < .01], lower baseline serum prolactin levels [1414 mcg/L (489-3586) vs. 4119 mcg/L (2715-6315), p < .01], lower rates of central hypogonadism (78.3% vs. 93.3%, p = .05) and central hypothyroidism (20.8% vs. 53.3%, p = .04), lower rates of compressive optic neuropathy (35.3% vs. 87.5%, p = .02) and a better visual acuity (better than 6/8 in both eyes, 93.7% vs. 28.6%, p < .01). CONCLUSIONS: In our cohort of 150 patients with macroprolactinoma, 40 patients (26.7%) presented with visual field defects, of which 61.5% achieved complete visual recovery with treatment. Patients that achieved complete visual recovery presented with smaller macroadenomas, lower serum prolactin levels, lower rates of central hypogonadism and central hypothyroidism, lower rates of compressive optic neuropathy and better visual acuity.

Curcumin affects autophagy of prolactinoma cells by upregulating miR-206 to exert antitumor effects.

We explored the effects of curcumin on the aberrant biological behaviors of prolactinoma cells and the downstream pathways through which curcumin exerts its antitumor effects. We used quantitative reverse transcription-polymerase chain reaction assays to measure miR-206 expression levels in peripheral blood samples from patients with prolactinoma before and after curcumin treatment. We also investigated the proliferation level, viability, and invasion ability of groups of cells treated with different concentrations of curcumin using 3-(4,5)-dimethylthiahiazo (-z-y1)-3-di-phenytetrazoliumromide (MTT) assays, cell cloning assays, and Transwell assays, respectively. Furthermore, we determined the levels of autophagy-related proteins and protein kinase B/mammalian target of the rapamycin (Akt/mTOR) signaling pathway-related proteins in each group of treated cells by western blot. Curcumin treatment upregulated miR-206 expression levels in the peripheral blood of patients with prolactinoma and in GH3 cells. Knockdown of miR-206 expression enhanced the proliferation and invasive ability of GH3 cells, while curcumin treatment effectively inhibited the aberrant biological behavior of GH3 cells enhanced by miR-206 knockdown. miR-206 knockdown also activated the Akt/mTOR signaling pathway and inhibited autophagy in GH3 cells, and these changes were effectively reversed by curcumin treatment. Thus, curcumin inhibited the Akt/mTOR signaling pathway and promoted cell autophagy by miR-206 upregulation, resulting in antitumor effects that inhibited prolactinoma cell proliferation and invasion.

Paradoxical effect of dopamine-agonists on IGF-1 in patients with prolactinoma: the role of weight.

PURPOSE: An increase of IGF-1 has been reported during therapy with dopamine agonists (DA) for prolactinomas; in such cases a correct diagnosis is pivotal to avoid an unnecessary reduction or withdrawal of DA, which are needed to maintain normal prolactin levels. This study was aimed to measure IGF-1 levels, at baseline and during follow-up, in a cohort of patients with prolactinoma, treated with cabergoline, stratified by body mass index. METHODS: We retrospectively enrolled 35 patients (15 F/20 M; age m ± SD, years: 43.4 ± 13.7) with prolactinoma (21 microadenomas and 14 macroadenomas) who were followed-up at the Endocrinology Unit, in Siena, and with available pituitary hormone assessment at baseline and during follow-up (m ± SD, years: 2.74 ± 0.55). RESULTS: IGF-1 increased in the whole cohort, but remaining within normal range, except two patients, in whom acromegaly was ruled out with oral glucose tolerance test. After dividing patients by weight, this trend was confirmed only in subjects with overweight and obesity (OV/OB) (p = 0.04). Interestingly, the reduction of prolactin levels was significantly greater in the OV/OB compared to normal-weight patients (median decrease of 97.5% versus 88.2%, p = 0.04). CONCLUSIONS: Since DA and normalization of prolactin are known to improve insulin sensitivity, we speculated they have favored the increase of IGF-1 in OV/OB. Our results should be confirmed and the hypothesis proven by further studies.

Network pharmacology analysis and molecular mechanism of paeoniflorin and its metabolite in prolactinoma cells.

Prolactinoma was the most common functional pituitary neuroendocrine tumor tissue type, which was caused by excessive proliferation of pituitary prolactin (PRL) cells. Drug therapy of dopamine receptor agonists was generally considered as the prior treatment for prolactinoma patients. However, there were still prolactinoma patients who were resistant to dopamine agonists. Studies have been reported that paeoniflorin can inhibit the secretion of PRL in prolactinoma cells lacking dopamine D2 receptor (D2R) expression, and paeoniflorin can be metabolized into albiflorin by intestinal flora in rats. The effect of albiflorin on prolactinoma has not been reported yet. In this study, network pharmacology was used to analyze the mechanism of paeoniflorin and its metabolite albiflorin as multi-target therapy for prolactinoma, and the experimental verification was carried out. In order to clarify the complex relationship among paeoniflorin, albiflorin and prolactinoma, we constructed a component-target-disease network, and further constructed interaction network, MMP9, EGFR, FGF2, FGFR1 and LGALS3 were screened as the core targets. Kyoto encyclopedia of genes and genomes (KEGG) analysis showed that paeoniflorin and albiflorin may be involved in various pathways in the treatment of prolactinoma, included relaxin signaling pathway and PI3K-Akt signaling pathway. Molecular docking analysis showed that paeoniflorin and albiflorin had good binding activity with MMP9. Western blotting results showed that paeoniflorin and albiflorin could significantly reduce the expression of MMP9, and ELISA results showed that paeoniflorin and albiflorin could significantly reduce the concentration of PRL in GH3 cells, and the reduce degree of albiflorin was stronger than paeoniflorin at 50 µM, which indicated that albiflorin might be a potential drug to treat prolactinoma, which can regulate prolactinoma through MMP9 and reduce the concentration of PRL. Our study provided a new therapeutic strategy for prolactinoma.

Prolactin-secreting tumors, dopamine agonists and pregnancy: a longitudinal experience of a tertiary neuroendocrine center.

PURPOSE: Prolactin (PRL)-secreting tumours are associated with infertility and can be reverted by dopamine agonist (DA) therapy. The suspension of DA is recommended once pregnancy is established, as all DAs cross the placenta. The aim of the study was to evaluate the rate of maternal-foetal complications in women treated with cabergoline (CAB) or bromocriptine (BRM) for prolactinoma during gestation and the effect of pregnancy on prolactinoma progression. METHODS: This was a retrospective observational study involving 43 women affected by prolactinoma who became pregnant during therapy with CAB or BRM for a total of 58 pregnancies. For each patient, medical records were analysed by integrating the data with outpatient or telephone interview. RESULTS: At the time of conception, 18 women were in the BRM group, while 40 were in CAB group. No differences were found in obstetric or neonatal outcomes between the two groups. There was a significant difference (p = 0.046) in child complications reported in maternal interview found exclusively in the CAB group. No further confounding factors were detected. Disease remission rate after the first pregnancy was 42.9% and the main predictor was a lower PRL nadir before pregnancy (p = 0.023). No difference was detected between the two groups in terms of tumor remission. Breastfeeding did not modify the outcome. CONCLUSION: Foetal exposure to DAs during the first weeks of embryogenesis is not associated with a greater risk of complications. The transient and mild developmental disorders recorded resolved spontaneously and the prevalence was substantially overlapping with that observed in the general population.

Quality of life in Prolactinoma: A systematic review.

BACKGROUND: Prolactinomas are common tumours that significantly reduce quality-of-life (QOL) due to sellar mass effect, secondary hypogonadism, and the peripheral effects of prolactin. Understanding the factors that influence QOL would provide insights into therapeutic targets to optimise patient outcomes and improve wellbeing in prolactinoma. METHODS: A systematic review was performed in accordance with the PRISMA statement. Studies that reported patient QoL using validated metrics were included. Bias and methodological rigour were assessed using the MINORS criteria. RESULTS: A total of 18 studies were identified studies were available for review, comprising 877 patients. Most were small cross-sectional studies at high risk of bias. Prolactinoma exhibit worse QOL than healthy controls, particularly mental and psychosocial wellbeing. QOL is also worse than patients with non-functional adenomas, but better than those with Cushing's disease and acromegaly. QOL correlates with prolactin levels, and approaches population baseline with prolonged biochemical control. Dopamine agonists and surgery both improve overall QOL, however improvements are more rapid with surgery. CONCLUSION: Poor quality of life in prolactinoma is multifactorial, related to biochemical control, side effects of therapy, and sellar mass effect. Targeting persistent symptoms, reducing healthcare costs, and reducing side-effects of therapy are avenues to improving QOL in patients with prolactinoma.

Recovery from hypogonadism in men with prolactinoma treated with dopamine agonists.

PURPOSE: In men with prolactinoma treated with dopamine agonists (DA), the extent, timeline, and predictive factors of gonadotropic axis recovery are still unclear. METHODS: We analyzed data of 97 men with a prolactinoma treated with DA (77/97 macroprolactinomas). We excluded patients with primary hypogonadism, surgery < 12 months after DA initiation, and patients with tumors < 5 mm or prolactin < 45 µg/l at diagnosis. RESULTS: Among the 97 patients, 12 had normal total testosterone (NT group) and 85 had low testosterone at diagnosis (LT group). In the NT group, testosterone rose from a mean of 13.5 nmol/l to 17.1nmol/l at 6 months (n = 11; p < 0.05) then remained stable at 12 months (n = 8). In the LT group, testosterone rose from a mean of 5.2 nmol/l to 9.6 nmol/l at 6 months (n = 66; p < 0.001) and further to 13.1nmol/l at 12 months (n = 40; p < 0.001) then remained stable. Recovery from hypogonadism occurred in 43%, 50%, and 54% of patients at 6, 12 and 24 months, respectively (61%, 69 and 69% if prolactin was normal). Factors independently associated with persistent hypogonadism at 12 months were at baseline the presence of visual field deficit and lower testosterone levels, while the most significant independent predictor of persistent hypogonadism at one year was a testosterone level < 7.4 nmol/l at 6 months, with 91% sensitivity and 94% specificity. CONCLUSION: Testosterone levels recover in a small majority of men with prolactinoma mostly during the first year of DA treatment. However, testosterone replacement could be considered earlier in patients with large and compressive tumors, and in whom testosterone remains below 7.4 nmol/l after 6 months of DA treatment.

Impulse control disorders in patients with dopamine agonist-treated pituitary adenomas: a cross-sectional multicenter study.

BACKGROUND: Impulse control disorders (ICDs) have been described as underrecognized side effects of dopamine agonists (DAs) in neurological disorders but are not sufficiently understood in endocrine conditions. OBJECTIVE: To identify the prevalence of DAs induced ICDs and determine potential risk factors related to these disorders in patients with prolactinoma and non-function pituitary adenomas (NFPAs). METHODS: This is a cross-sectional multicenter study involving 200 patients with prolactinoma and NFPAs, who received follow-ups in tertiary referral centers. DA-induced ICDs were assessed using ICD questionnaires modified from prior studies. RESULT: At least one ICD was reported by 52% of participants, among whom 28.5% mentioned compulsive shopping, 24.5% punding, and 24.5% hypersexuality. Furthermore, 33% of the patients reported the presence of one type of ICD behavior, while 12% specified two and 7% had three types of such behavior. The multivariable logistic regression showed that the significant risk factors of ICD were younger age (adjusted odds ratio [AOR]: 0.92, 95% confidence interval [CI]: 0.88-0.97, p 0.001), being single (AOR: 0.15, 95%CI: 0.03-0.84, p 0.03), and a positive history of psychiatric illness (AOR: 7.67, 95% CI: 1.37-42.97, p 0.021). CONCLUSION: ICDs with a broad range of psychiatric symptoms are common in individuals with DA-treated prolactinoma and NFPAs. Endocrinologists should be aware of this potential side effect, particularly in patients with a personal history of psychiatric disorder.

Clinical use of [18F]fluoro-ethyl-L-tyrosine PET co-registered with MRI for localizing prolactinoma remnants.

PURPOSE: To assess the utility of [18F]fluoroethyl-L-tyrosine PET co-registered with magnetic resonance imaging ([18F]FET-PET/MRICR) in patients with difficult-to-localize prolactinoma to inform clinical decision-making and (surgical) treatment planning. METHODS: Retrospective cohort study of 17 consecutive patients with prolactinoma undergoing [18F]FET-PET/MRICR between October 2020 and September 2022 for either (1) additional information in case of difficult-to-visualize remnants after prior transsphenoidal surgery (TSS), or pharmacological treatment, or (2) radiological diagnosis in absence of a (clear) adenoma on diagnostic/post-treatment conventional MRI. RESULTS: [18F]FET-PET/MRICR identified a lesion in 14/17 patients, yet failed to identify active lesions in 2 patients with negative conventional MRI despite prolactin > 7.5 times upper limit of normal. [18F]FET-PET/MRICR results were inconclusive in 1 patient due to diffuse tracer uptake 10 weeks post-surgery. [18F]FET-PET/MRICR was completely concordant with a suspected lesion on conventional MRI in 10/17 patients, and partially concordant in 3/17 patients. New foci were identified in 4/17 patients. The [18F]FET-PET/MRICR conclusions influenced clinical shared decision-making in 15/17 patients, of whom 7 patients underwent TSS and 8 refrained from TSS. One patient underwent TSS despite negative [18F]FET-PET/MRICR, and one patient underwent additional imaging. Intraoperative findings corresponded with [18F]FET-PET/MRICR in 5/8 patients, and immunohistochemistry was positive in 5/8 patients. The treatment goal was achieved in 7/8 patients, and remission was achieved in 5/7 patients in whom total resection was considered feasible. CONCLUSION: [18F]FET-PET/MRICR can be of added value in the preoperative decision-making process for selected patients with difficult-to-localize prolactinoma (remnants), or patients lacking a substrate on conventional MRI.

Surveillance Imaging Strategies for Pituitary Adenomas: When, How Frequent, and When to Stop.

OBJECTIVE: To describe a practical approach of when and how often to perform imaging, and when to stop imaging pituitary adenomas (PAs). METHODS: A literature review was carried out and recommendations provided are derived largely from personal experience. RESULTS: Magnetic resonance imaging is the mainstay imaging modality of choice in the assessment, treatment planning, and follow-up of PAs. These adenomas are discovered incidentally during imaging for a variety of unrelated conditions, because of clinical symptoms related to mass effects on the adjacent structures, or during workup for functional alterations of the adenoma. Imaging is also used in the preoperative and postoperative phases of assessment of PAs, for surgical and radiotherapy planning, for postoperative surveillance to assess for adenoma stability and detection of adenoma recurrence, and for surveillance to monitor for adenoma growth in unoperated PAs. Currently, because there are no evidence-based consensus recommendations, the optimal strategy for surveillance imaging of PAs is not clearly established. Younger age, initial adenoma size, extrasellar extension, mass effect, cavernous sinus invasion, functional status, histopathologic characteristics, cost considerations, imaging accessibility, patient preference, and patient contraindications (eg, implanted metallic devices and patient claustrophobia) are all important factors that influence the strategy for surveillance imaging. CONCLUSIONS: This review provides a practical approach of performing surveillance imaging strategies for PAs that should be individualized based on clinical presentation, history, adenoma morphology on imaging, and histopathologic characteristics.

Bromocriptine sensitivity in bromocriptine-induced drug-resistant prolactinomas is restored by inhibiting FGF19/FGFR4/PRL.

PURPOSE: At present, various treatment strategies are available for pituitary adenomas, including medications, surgery and radiation. The guidelines indicate that pharmacological treatments, such as bromocriptine (BRC) and cabergoline (CAB), are important treatments for prolactinomas, but drug resistance is an urgent problem that needs to be addressed. Therefore, exploring the mechanism of drug resistance in prolactinomas is beneficial for clinical treatment. METHODS: In our research, BRC-induced drug-resistant cells were established. Previous RNA sequencing data and an online database were used for preliminary screening of resistance-related genes. Cell survival was determined by Cell Counting Kit-8 (CCK-8) assay, colony formation assays and flow cytometry. Quantitative real-time polymerase chain reaction (qRT‒PCR), western blotting, immunohistochemistry, immunofluorescence and Co-immunoprecipitation (Co-IP) were used to assess the molecular changes and regulation. The therapeutic efficacy of BRC and FGFR4 inhibitor fisogatinib (FISO) combination was evaluated in drug-resistant cells and xenograft tumors in nude mice. RESULTS: Consistent with the preliminary results of RNA sequencing and database screening, fibroblast growth factor 19 (FGF19) expression was elevated in drug-resistant cells and tumor samples. With FGF19 silencing, drug-resistant cells exhibited increased sensitivity to BRC and decreased intracellular phosphorylated fibroblast growth factor receptor 4 (FGFR4) levels. After confirming that FGF19 binds to FGFR4 in prolactinoma cells, we found that FGF19/FGFR4 regulated prolactin (PRL) synthesis through the ERK1/2 and JNK signaling pathways. Regarding the effect of targeting FGF19/FGFR4 on BRC efficacy, FISO and BRC synergistically inhibited the growth of tumor cells, promoted apoptosis and reduced PRL levels. CONCLUSION: Overall, our study revealed FGF19/FGFR4 as a new mechanism involved in the drug resistance of prolactinomas, and combination therapy targeting the pathway could be helpful for the treatment of BRC-induced drug-resistant prolactinomas.

Nonalcoholic Fatty Liver Disease, Bone and Muscle Quality in Prolactinoma: A Pilot Study.

OBJECTIVE: Hyperprolactinemia has negative impacts on metabolism and musculoskeletal health. In this study, individuals with active prolactinoma were evaluated for nonalcoholic fatty liver disease (NAFLD) and musculoskeletal health, which are underemphasized in the literature. METHODS: Twelve active prolactinoma patients and twelve healthy controls matched by age, gender, and BMI were included. Magnetic resonance imaging-proton density fat fraction (MRI-PDFF) was used to evaluate hepatic steatosis and magnetic resonance elastography (MRE) to evaluate liver stiffness measurement (LSM). Abdominal muscle mass, and vertebral MRI-PDFF was also evaluated with MRI. Body compositions were evaluated by dual energy X-ray absorptiometry (DXA). The skeletal muscle quality (SMQ) was classified as normal, low and weak by using "handgrip strength/appendicular skeletal muscle mass (HGS/ASM)" ratio based on the cut-off values previously stated in the literature. RESULTS: Prolactin, HbA1c and CRP levels were higher in prolactinoma patients (p<0.001, p=0.033 and p=0.035, respectively). The median MRI-PDFF and MRE-LSM were 3.0% (2.01-15.20) and 2.22 kPa (2.0-2.5) in the prolactinoma group and 2.5% (1.65-10.00) and 2.19 kPa (1.92-2.54) in the control group, respectively and similiar between groups. In prolactinoma patients, liver MRI-PDFF showed a positive and strong correlation with the duration of disease and traditional risk factors for NAFLD. Total, vertebral and pelvic bone mineral density was similar between groups, while vertebral MRI-PDFF tended to be higher in prolactinoma patients (p=0.075). Muscle mass and strength parameters were similar between groups, but HGS/ASM tended to be higher in prolactinoma patients (p=0.057). Muscle mass was low in 33.3% of prolactinoma patients and 66.6 of controls. According to SMQ, all prolactinoma patients had normal SMQ, whereas 66.6% of the controls had normal SMQ. CONCLUSION: Prolactinoma patients demonstrated similar liver MRI-PDFF and MRE-LSM to controls despite their impaired metabolic profile and lower gonadal hormone levels. Hyperprolactinemia may improve muscle quality in prolactinoma patients despite hypogonadism.

Characteristics and outcomes of men with erectile dysfunction as the presenting symptom due to a lactotroph adenoma.

PURPOSE: Erectile dysfunction (ED) is frequently underreported in men suffering from prolactinomas and can be challenging to manage. Both dopamine agonists (DAs) and transsphenoidal surgery (TSS) correct hyperprolactinemia and restore gonadal function. However, there is scarce data regarding their effectiveness in correcting ED over the long term. METHODS: This study is a retrospective single-center comparative cohort study analyzing men diagnosed with prolactinomas, both with and without confirmed erectile dysfunction (ED) at diagnosis. Independent risk factors for persistent ED over the long term were examined using multivariate logistic regression. RESULTS: Among the 39 men with lactotroph adenomas, ED was one of the presenting symptoms in 22 (56%). The mean age at diagnosis was 45 ± 12 years. Surgery was the primary treatment in 6 (27%) ED patients and 8 (47%) non-ED patients. After a mean follow-up of 74 ± 48 months, remission from hyperprolactinemia was achieved in the majority (76%) of men: 71% in the non-ED cohort and 81% in the ED group (p = 0.70), regardless of the primary treatment strategy (surgical 84% versus medical 72%, p = 0.46). Long-term remission of ED was noted in 16 (73%) patients. Interestingly, high baseline BMI levels emerged as potential risk factors for persistent ED over the long term (OR 1.4, 95%CI 1.0-1.9; p = 0.04), while neither the initial adenoma size nor the primary treatment strategy (i.e., TSS vs. DAs) reached statistical significance. CONCLUSIONS: Correcting hyperprolactinemia and its associated hypogonadism significantly improves ED in the majority of men with prolactinomas over the long term, regardless of the primary treatment strategy employed. In addition to addressing endocrine deficiencies, the early initiation of weight control programs may be considered for men with lactotroph adenomas and ED. Although our study suggests an association between BMI and the risk of persistent ED, further research is needed to establish any causal relationships.

Preoperative treatment with dopamine agonist therapy influences surgical outcome in prolactinoma: a retrospective single-center on 159 patients.

INTRODUCTION: Prolactinoma account to the most common pituitary adenomas and current therapy regime constitutes of dopamine agonist therapy (DA) and surgery in selected cases [17]. Due to tumor fibrosis induced by previous DA therapy, surgical removal can be challenging though. Therefore, this study investigates how preoperative DA usage influences perioperative treatment and surgical outcome in prolactinoma and aims to ascertain whether a specific subgroup of prolactinoma patients could derive greater benefit from exclusive surgical intervention. METHODS: We retrospectively analyzed n = 159 surgically treated and histologically confirmed prolactinomas in the sella region from 2013-2022 in our institution. Clinical, radiological and surgical features were analyzed. Univariate and multivariate analyses were performed. RESULTS: Out of total of 159 prolactinoma patients, 83.6% received previous treatment with DA followed by surgery, while only 16.4% received exclusive surgery. Both groups presented similar initial tumor volumes (1.9cm3 vs. 1.5cm3, p = 0.59) and equal preoperative prolactin levels (PRL) (199.7 µg/l vs. 191.0 µg/l, p = 0.44). Surgical procedures took significantly longer when patients received prior DA treatment (79 min. vs. 70 min., p = 0.0479). Six months after surgery, pretreated patients revealed significantly higher PRL compared to non-treated (107 g/l vs. 8.64 µg/, p = 0.0009). Additionally, untreated microprolactinoma presented a remission of 100%, whereas pretreated exhibited a remission rate of 88.75%. CONCLUSION: The current study demonstrates that prior DA treatment is associated with significantly longer surgeries, higher recurrence rates and lower rates of normalization of PRL levels after surgery, particularly in microprolactinomas and support the latest recommendations of the Pituitary Society's Consensus Statement 2023, which favors the option of surgery alone as first-line therapy for microprolactinomas.

Prolactin in headache and migraine: A systematic review of clinical studies.

OBJECTIVE: To systemically review clinical studies investigating the role of prolactin and its receptors in headache and migraine. BACKGROUND: Migraine prevalence is more common in women compared to men. As prolactin is a crucial regulator of the hypothalamus-pituitary-gonadal axis, prolactin and its receptors might contribute to signaling mechanisms underlying migraine. METHODS: In this systematic review, we searched PubMed and EMBASE with the terms: prolactin, hyperprolactinemia, macroprolactinemia, hypoprolactinemia, migraine, headache, head pain and trigeminal pain pathway for clinical studies investigating prolactin signaling in headache and migraine. Two reviewers independently screened 841 articles for population, intervention, comparison, outcome, and study design. Studies were restricted to the English language and were excluded if they had a nonexperimental methodology. RESULTS: Nineteen clinical studies met the inclusion criteria and were included in the qualitative and quantitative analysis. The main findings were that serum prolactin levels were found to be higher in individuals with migraine compared to healthy controls, and prolactinomas (prolactin-secreting pituitary adenomas) were correlated with higher incidence of headache in otherwise healthy individuals and migraine attacks in individuals with migraine. CONCLUSION: Considerable evidence suggests a key role of prolactin and its receptors in migraine pathophysiology. Further randomized and placebo-controlled clinical studies targeting prolactin signaling are needed to further clarify influences of prolactin in migraine attack initiation.

Levodopa-refractory hyperprolactinemia and pituitary findings in inherited disorders of biogenic amine metabolism.

Elevated serum prolactin concentrations occur in inherited disorders of biogenic amine metabolism because dopamine deficiency leads to insufficient inhibition of prolactin secretion. This work from the International Working Group on Neurotransmitter Related Disorders (iNTD) presents the results of the first standardized study on levodopa-refractory hyperprolactinemia (LRHP; >1000 mU/L) and pituitary magnetic resonance imaging (MRI) abnormalities in patients with inherited disorders of biogenic amine metabolism. Twenty-six individuals had LRHP or abnormal pituitary findings on MRI. Tetrahydrobiopterin deficiencies were the most common diagnoses (n = 22). The median age at diagnosis of LRHP was 16 years (range: 2.5-30, 1st-3rd quartiles: 12.25-17 years). Twelve individuals (nine females) had symptoms attributed to hyperprolactinemia: menstruation-related abnormalities (n = 7), pubertal delay or arrest (n = 5), galactorrhea (n = 3), and decreased sexual functions (n = 2). MRI of the pituitary gland was obtained in 21 individuals; six had heterogeneity/hyperplasia of the gland, five had adenoma, and 10 had normal findings. Eleven individuals were treated with the dopamine agonist cabergoline, ameliorating the hyperprolactinemia-related symptoms in all those assessed. Routine monitoring of these symptoms together with prolactin concentrations, especially after the first decade of life, should be taken into consideration during follow-up evaluations. The potential of slow-release levodopa formulations and low-dose dopamine agonists as part of first-line therapy in the prevention and treatment of hyperprolactinemia should be investigated further in animal studies and human trials. This work adds hyperprolactinemia-related findings to the current knowledge of the phenotypic spectrum of inherited disorders of biogenic amine metabolism.

Prolactin in headache and migraine: A systematic review of preclinical studies.

OBJECTIVE: To systemically review preclinical studies investigating the implication of prolactin signaling in headache and migraine pathophysiology. BACKGROUND: The features of migraine attacks, including characteristics, duration, frequency, and prevalence, are sex-dependent with variability across a lifetime, indicating the involvement of the hypothalamus-pituitary-gonadal axis. Prolactin is a key regulator of this axis, and a new line of evidence implicates prolactin signaling in sex-related differences in pain perception. METHODS: In this systematic review, we searched PubMed and EMBASE for the terms prolactin, hyperprolactinemia, macroprolactinemia, hypoprolactinemia, migraine, headache, head pain, and trigeminal pain pathway to find preclinical studies investigating prolactin signaling in headache and migraine. Two reviewers independently screened 841 articles for population, intervention, comparison, outcome, and study design. Studies were restricted to the English language and were excluded if they had a nonexperimental methodology. RESULTS: Of a total of 15 preclinical articles selected, 11 were both ex vivo and in vivo, 3 were ex vivo, and 1 was an in vivo study. The main findings were that prolactin receptors are distributed in the trigeminal pain pathway, and prolactin induced migraine-like behavior in rodents. Moreover, prolactin signaling has a crucial role in calcitonin gene-related peptide (CGRP) release, a key molecule in migraine pathogenesis, and prolactin gene deletion attenuated CGRP-induced migraine-like behavior. CONCLUSION: Preclinical data indicate a key role of prolactin and its receptors in mechanisms causing migraine. Further randomized and placebo-controlled clinical studies targeting prolactin signaling are needed to further clarify the influences of prolactin in migraine-attack initiation.

What is the optimal prolactin cutoff for predicting the presence of a pituitary adenoma in patients with polycystic ovary syndrome?

Objective: Hyperprolactinemia (HPRL) and polycystic ovary syndrome (PCOS) are common causes of infertility in women of reproductive age. A pituitary adenoma (PA) is the most common type of brain tumor that causes HPRL. In the neurosurgical field, the co-existence of PA and PCOS is not common. However, neurosurgeons often treat patients who are referred from gynecology. Because most of these patients are young and reproductive-aged, it is difficult for a neurosurgeon to come up with a treatment plan alone. In this study, we investigated the prevalence of PAs in PCOS patients, the cutoff prolactin (PRL) level to detect PAs, and the treatment strategy, then assessed the relationship between these diseases via a literature review. Methods: Medical records from November 2009 to March 2020 were reviewed at our institute. A total of 657 PCOS patients were enrolled. Initial prolactin levels were investigated and hyperprolactinemic patients were selected. As a result of sella magnetic resonance imaging (MRI), patients were divided into 2 groups of those with hyperprolactinemia but without PAs (group A) and those with both hyperprolactinemia and PAs (group B), respectively. We then compared and analyzed each group to find the characteristics and statistical differences. Receiver operating characteristic (ROC) curve analysis was performed to determine a cutoff value of the serum PRL level that could detect PAs in hyperprolactinemic PCOS patients. Results: Of 657 patients diagnosed with PCOS, 76 patients had hyperprolactinemia (76/657, 11.6%). Sella MRI was performed in 56 patients, excluding 20 patients for various reasons. Patients in groups A and B numbered 43 and 13, respectively, and the mean serum prolactin level significantly differed between the groups (39.89 ± 41.64 vs. 108.59 ± 60.70 ng/mL, P < 0.001). Based on the ROC curve analysis of the prolactin threshold level for predicting PAs in PCOS patients, the area under the ROC curve was 0.853 (95% confidence interval, 0.733-0.934; P < 0.001), and the sensitivity and specificity were 76.9% and 86.1%, respectively. Ultimately, the cutoff value for prolactin level was 52.9 ng/mL. Conclusion: PCOS and hyperprolactinemia are common causes of infertility in reproductive-age women. PCOS patients with a PRL level of ≥ 52.9 ng/mL may need to undergo sella MRI for detecting PAs. To help ensure a favorable clinical course for these patients, systematic diagnosis, treatment, and follow-up plan should be established. Therefore, a multidisciplinary approach involving both neurosurgery and gynecology is essential.

Refractory lactotroph adenomas.

A small subset of lactotroph adenomas is resistant to dopamine agonists (DA) and can also demonstrate aggressive or even malignant behavior. The implicated mechanisms are not clearly defined. Management can be challenging and requires a multidisciplinary approach. In DA resistant prolactinomas, switching to another DA could be the first option to consider. Further strategies include surgery and radiotherapy used alone or in combination. In cases of aggressive or malignant prolactinomas, temozolomide could be offered. Immune checkpoint inhibitors have been also recently proposed as an alternative approach. The place of other treatments (e.g., metformin, selective estrogen modulators, somatostatin analogues, tyrosine kinase inhibitors, inhibitors of mammalian target of rapamycin and peptide radio-receptor therapy) remains to be carefully assessed.

Giant prolactinomas, a detailed analysis of 196 adult cases.

PURPOSE: Giant prolactinomas are a rare entity, representing approximately 5% of all prolactinomas. A systematic review of 196 adult cases was performed. A comparison of the clinical, biochemical and radiological characteristics, management and therapeutic outcomes in men versus women is made. METHODS: A structured search was conducted using the term 'giant prolactinoma'. Following inclusion criteria were used: diameter ≥ 40 mm, prolactin levels > 1000 ng/ml and no concomitant GH/ ACTH secretion. RESULTS: 196 cases were included [age: 38 (28-50) years, F/M ratio: 1/3.6]. Median tumor diameter was 53 (43-69) mm. Pituitary deficiency was present in 91% of cases, with hypogonadotropic hypogonadism being the most frequent. Most common presenting symptoms were visual impairment (73%) and headache (50%) in men and amenorrhea (58%) in women. 82% of cases were treated with a dopamine agonist (DA) as first-line treatment which led to normoprolactinemia, tumor shrinkage and visual improvement in 51%, 88% and 85% of cases, respectively. Surgery was performed in 29% of cases and all showed tumor remnant and persistent hyperprolactinemia. Women had a lower prolactin level and a smaller tumor diameter at diagnosis but pituitary deficiencies were more frequent and outcome was worse. CONCLUSION: Giant prolactinomas are rare and have a male predominance. Visual impairment is the most frequent presenting symptom in men and amenorrhea in women. The gender-related difference in tumor size and level of prolactin was confirmed in this analysis where men had a larger diameter and a higher baseline prolactin level. DAs are the treatment of choice, irrespective of tumor size and presence of visual impairment. As only half of the cases achieved normoprolactinemia we do not, in contrast to previous literature, state giant prolactinomas to be exquisitely sensitive to DAs. Patient characteristics associated with persistent hyperprolactinemia after treatment with a DA were female gender, higher baseline prolactin and larger tumor size . This analysis did show TSH- and ACTH-deficiency to be more frequent after surgery which was not seen for LH/FSH deficiency.