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Pituitary Oct 2023Giant prolactinomas are a rare entity, representing approximately 5% of all prolactinomas. A systematic review of 196 adult cases was performed. A comparison of the... (Review)
Review
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.
Topics: Female; Adult; Male; Humans; Prolactinoma; Pituitary Neoplasms; Hyperprolactinemia; Prolactin; Amenorrhea; Dopamine Agonists; Hypopituitarism; Vision Disorders; Adrenocorticotropic Hormone
PubMed: 37544978
DOI: 10.1007/s11102-023-01337-0 -
Arquivos de Neuro-psiquiatria Dec 2018Optimizing idiopathic Parkinson's disease treatment is a challenging, multifaceted and continuous process with direct impact on patients' quality of life. The basic... (Review)
Review
Optimizing idiopathic Parkinson's disease treatment is a challenging, multifaceted and continuous process with direct impact on patients' quality of life. The basic tenet of this task entails tailored therapy, allowing for optimal motor function with the fewest adverse effects. Apomorphine, a dopamine agonist used as rescue therapy for patients with motor fluctuations, with potential positive effects on nonmotor symptoms, is the only antiparkinsonian agent whose capacity to control motor symptoms is comparable to that of levodopa. Subcutaneous administration, either as an intermittent injection or as continuous infusion, appears to be the most effective and tolerable route. This review summarizes the historical background, structure, mechanism of action, indications, contraindications and side effects, compares apomorphine infusion therapy with other treatments, such as oral therapy, deep brain stimulation and continuous enteral infusion of levodopa/carbidopa gel, and gives practical instructions on how to initiate treatment.
Topics: Antiparkinson Agents; Apomorphine; Carbidopa; Deep Brain Stimulation; Dopamine Agonists; Drug Combinations; Humans; Levodopa; Parkinson Disease
PubMed: 30698208
DOI: 10.1590/0004-282X20180140 -
Endocrine Jan 2018
Topics: Dopamine Agonists; Ergolines; Humans; Hyperprolactinemia; Neoplasm Recurrence, Local; Prolactin; Prolactinoma
PubMed: 29124662
DOI: 10.1007/s12020-017-1469-0 -
Current Opinion in Neurology Aug 2015Impulse control behaviours (ICBs) are a frequent comorbidity for patients with Parkinson's disease. They consist of impulse control disorders, dopamine dysregulation... (Review)
Review
PURPOSE OF REVIEW
Impulse control behaviours (ICBs) are a frequent comorbidity for patients with Parkinson's disease. They consist of impulse control disorders, dopamine dysregulation syndrome, and punding. The field continues to evolve in the understanding of impulsivity and assessment of risk factors in the development of these behaviours and their appropriate management in patients with Parkinson's disease.
RECENT FINDINGS
Impulsivity is a multifaceted concept that is surprisingly common in untreated patients with Parkinson's disease. The incidence of ICBs increases with demographic, clinical, and biochemical risk factors. Treatments rely on reduction of dopamine agonists with exception of cognitive behavioural therapy and possibly repetitive transcranial magnetic stimulation.
SUMMARY
Reduction of dopamine agonist dose is the mainstay of treatment of ICBs. Other forms of dopaminergic treatment such as deep brain stimulation or jejunal infusion are alternative treatments but may be complicated by dopamine agonist withdrawal syndrome. Other therapies show promise but data are insufficient to suggest their regular use.
Topics: Deep Brain Stimulation; Disruptive, Impulse Control, and Conduct Disorders; Dopamine Agonists; Humans; Impulsive Behavior; Parkinson Disease
PubMed: 26110803
DOI: 10.1097/WCO.0000000000000209 -
Pituitary Feb 2020Consensus guidelines recommend dopamine agonists (DAs) as the mainstay treatment for prolactinomas. In most patients, DAs achieve tumor shrinkage and normoprolactinemia... (Review)
Review
Consensus guidelines recommend dopamine agonists (DAs) as the mainstay treatment for prolactinomas. In most patients, DAs achieve tumor shrinkage and normoprolactinemia at well tolerated doses. However, primary or, less often, secondary resistance to DAs may be also encountered representing challenging clinical scenarios. This is particularly true for aggressive prolactinomas in which surgery and radiotherapy may not achieve tumor control. In these cases, alternative medical treatments have been considered but data on their efficacy should be interpreted within the constraints of publication bias and of lack of relevant clinical trials. The limited reports on somatostatin analogues have shown conflicting results, but cases with optimal outcomes have been documented. Data on estrogen modulators and metformin are scarce and their usefulness remains to be evaluated. In many aggressive lactotroph tumors, temozolomide has demonstrated optimal outcomes, whereas for other cytotoxic agents, tyrosine kinase inhibitors and for inhibitors of mammalian target of rapamycin (mTOR), higher quality evidence is needed. Finally, promising preliminary results from in vitro and animal reports need to be further assessed and, if appropriate, translated in human studies.
Topics: Cabergoline; Dopamine Agonists; Female; Humans; Male; Prolactinoma
PubMed: 31522358
DOI: 10.1007/s11102-019-00987-3 -
Frontiers in Endocrinology 2022Prolactin is a polypeptide hormone that is well known for its role in reproductive physiology. Recent studies highlight its role in neurohormonal appetite regulation and... (Review)
Review
Prolactin is a polypeptide hormone that is well known for its role in reproductive physiology. Recent studies highlight its role in neurohormonal appetite regulation and metabolism. Elevated prolactin levels are widely associated with worsening metabolic disease, but it appears that low prolactin levels could also be metabolically unfavorable. This review discusses the pathophysiology of prolactin related metabolic changes, and the less commonly recognized effects of prolactin on adipose tissue, pancreas, liver, and small bowel. Furthermore, the effect of dopamine agonists on the metabolic profiles of patients with hyperprolactinemia are discussed as well.
Topics: Dopamine Agonists; Humans; Hyperprolactinemia; Pituitary Neoplasms; Prolactin; Prolactinoma
PubMed: 36246929
DOI: 10.3389/fendo.2022.1002320 -
Pituitary Apr 2023Dopamine 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.... (Review)
Review
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.
Topics: Female; Humans; Prolactinoma; Dopamine Agonists; Cabergoline; Pituitary Neoplasms; Hyperprolactinemia; Bromocriptine; Ergolines
PubMed: 37027090
DOI: 10.1007/s11102-023-01313-8 -
Biotechnology Journal Jun 2022Electrical stimulation of brain or muscle activities has gained attention for studying the molecular and cellular mechanisms involved in electric-induced responses. We...
Electrical stimulation of brain or muscle activities has gained attention for studying the molecular and cellular mechanisms involved in electric-induced responses. We recently showed zebrafish's response to electricity. Here, we hypothesized that this response is affected by the dopaminergic signaling pathways. The effects of multiple dopamine agonists and antagonists on the electric response of 6 days-postfertilization zebrafish larvae were investigated using a microfluidic device with enhanced control of experimentation and throughput. All dopamine antagonists decreased locomotor activities, while dopamine agonists did not induce similar behaviors. The D2-selective dopamine agonist quinpirole enhanced the movement. Exposure to nonselective and D1-selective dopamine agonists apomorphine and SKF-81297 caused no significant change in the electric response. Exposing larvae that were pretreated with nonselective and D2-selective dopamine antagonists butaclamol and haloperidol to apomorphine and quinpirole, respectively, restored the electric locomotion. These results reveal a correlation between electric response and dopamine signaling pathway. Furthermore, they demonstrate that electric-induced zebrafish larvae locomotion can be conditioned by modulating dopamine receptor functions. Our electrofluidic assay has profound application potential for fundamental electric-induced response research and brain disorder studies especially those related to the dopamine imbalance and as a chemical screening method when investigating biological pathways and behaviors.
Topics: Animals; Apomorphine; Dopamine; Dopamine Agonists; Dopamine Antagonists; Electricity; Larva; Quinpirole; Signal Transduction; Zebrafish
PubMed: 35332995
DOI: 10.1002/biot.202100561 -
Hormone and Metabolic Research =... Jul 2021Despite most of the prolactinomas can be treated with endocrine therapy and/or surgery, a significant percentage of these tumors can be resistant to endocrine treatments... (Review)
Review
Despite most of the prolactinomas can be treated with endocrine therapy and/or surgery, a significant percentage of these tumors can be resistant to endocrine treatments and/or recur with prominent invasion into the surrounding anatomical structures. Hence, clinical, pathological, and molecular definitions of aggressive prolactinomas are important to guide for classical and novel treatment modalities. In this review, we aimed to define molecular endocrinological features of dopamine agonist-resistant and aggressive prolactinomas for designing future multimodality treatments. Besides surgery, temozolomide chemotherapy and radiotherapy, peptide receptor radionuclide therapy, estrogen pathway modulators, progesterone antagonists or agonists, mTOR/akt inhibitors, pasireotide, gefitinib/lapatinib, everolimus, and metformin are tested in preclinical models, anecdotal cases, and in small case series. Moreover, chorionic gonadotropin, gonadotropin releasing hormone, TGFβ and PRDM2 may seem like possible future targets for managing aggressive prolactinomas. Lastly, we discussed our management of a unique prolactinoma case by asking which tumors' proliferative index (Ki67) increased from 5-6% to 26% in two subsequent surgeries performed in a 2-year period, exerted massive invasive growth, and secreted huge levels of prolactin leading up to levels of 1 605 671 ng/dl in blood.
Topics: Combined Modality Therapy; Dopamine Agonists; Drug Resistance, Neoplasm; Humans; Prognosis; Prolactinoma
PubMed: 34282593
DOI: 10.1055/a-1525-2131 -
Journal of Psychopharmacology (Oxford,... Mar 2021Cariprazine is a dopamine D-preferring D/D receptor partial agonist compound recently introduced to treat schizophrenia and bipolar disorder. Although cariprazine is...
BACKGROUND
Cariprazine is a dopamine D-preferring D/D receptor partial agonist compound recently introduced to treat schizophrenia and bipolar disorder. Although cariprazine is clinically classified as a low-somnolence drug, to date no detailed polysomnographic study is available on its effect on sleep.
AIMS
This study examined the acute systemic effects of cariprazine on the rat sleep architecture and electroencephalography spectral power.
METHODS
Sprague Dawley rats were recorded during their normal sleep period for four hours, and their sleep stages were classified.
RESULTS
Cariprazine (0.3 mg/kg i.p.) reduced the time spent in rapid eye movement (REM) sleep and increased REM latency. This dose of cariprazine decreased the gamma (40-80 Hz) band frequency oscillations and increased the theta (4-9 Hz) and alpha (9-15 Hz) frequencies during the wake periods but not during slow-wave sleep. The 0.03 mg/kg dose of cariprazine only increased the alpha power during the wake periods, while the 0.003 mg/kg dose was without any effect.
CONCLUSION
Taken together, the present results suggest that the REM-suppressing effect of cariprazine may be related to its effectiveness in improving depressive symptoms, as various drugs with similar REM-reducing properties effectively treat the depressive state, whereas the gamma power-reducing effect of cariprazine may be indicative of its efficacy in schizophrenia or mania, as similar effects have been observed with other D and 5-HT receptor antagonist drugs. These data contribute to our understanding of the complex mechanism of action that may stand behind the clinical efficacy of cariprazine.
Topics: Animals; Antipsychotic Agents; Dopamine Agonists; Electroencephalography; Male; Piperazines; Rats; Rats, Sprague-Dawley; Sleep; Sleep, REM
PubMed: 33406962
DOI: 10.1177/0269881120981378