Breast cancer risk in hyperprolactinemia: a population-based cohort study and meta-analysis of the literature

Diagnosis and management of prolactin-secreting pituitary adenomas: a Pituitary Society international Consensus Statement

This Consensus Statement from an international, multidisciplinary workshop sponsored by the Pituitary Society offers evidence-based graded consensus recommendations and key summary points for clinical practice on the diagnosis and management of prolactinomas. Epidemiology and pathogenesis, clinical presentation of disordered pituitary hormone secretion, assessment of hyperprolactinaemia and biochemical evaluation, optimal use of imaging strategies and disease-related complications are addressed. In-depth discussions present the latest evidence on treatment of prolactinoma, including efficacy, adverse effects and options for withdrawal of dopamine agonist therapy, as well as indications for surgery, preoperative medical therapy and radiation therapy. Management of prolactinoma in special situations is discussed, including cystic lesions, mixed growth hormone-secreting and prolactin-secreting adenomas and giant and aggressive prolactinomas. Furthermore, considerations for pregnancy and fertility are outlined, as well as management of prolactinomas in children and adolescents, patients with an underlying psychiatric disorder, postmenopausal women, transgender individuals and patients with chronic kidney disease. The workshop concluded that, although treatment resistance is rare, there is a need for additional therapeutic options to address clinical challenges in treating these patients and a need to facilitate international registries to enable risk stratification and optimization of therapeutic strategies.

Hyperprolactinaemia is common in Chinese premenopausal women with breast diseases

Purpose: Hyperprolactinaemia has been proposed to play a role in breast lesions pathophysiology. Thus far, controversial results have been reported for the relationship between hyperprolactinaemia and breast lesions. Moreover, the prevalence of hyperprolactinaemia in a population with breast lesions is scarcely reported. We aimed to investigate the prevalence of hyperprolactinaemia in Chinese premenopausal women with breast diseases, and explore the associations between hyperprolactinaemia with different clinical characteristics. Methods: This was a retrospective cross-sectional study performed in the department of breast surgery of Qilu hospital of Shandong University. Overall, 1,461 female patients who underwent the serum prolactin (PRL) level assay before breast surgery from January 2019 to December 2020 were included. Patients were divided into two groups: before and after menopause. Data were analyzed using SPSS 18.0 software. Results: The results showed an elevated PRL level in 376 of the 1,461 female patients with breast lesions (25.74%). Furthermore, the proportion of hyperprolactinemia among premenopausal patients with breast disease (35.75%, 340/951) was significantly higher than among postmenopausal patients with breast disease (7.06%, 36/510). In premenopausal patients, the proportion of patients with hyperprolactinaemia and the mean serum PRL level were significantly higher in those diagnosed with fibroepithelial tumours (FETs) and in younger patients (aged < 35 years) than in those with non-neoplastic lesions and in those aged ≥ 35 years (both p < 0.05). Especially, the prolactin level exhibited steady ascending tendency for positive correlation with FET. Conclusion: Hyperprolactinaemia is prevalent in Chinese premenopausal patients with breast diseases, especially in those with FETs, which implies a potential association, to some extent, between the PRL levels in various breast diseases.

Italian Association of Clinical Endocrinologists (AME) and International Chapter of Clinical Endocrinology (ICCE). Position statement for clinical practice: prolactin-secreting tumors

Prolactinomas are the most frequent pituitary adenomas. Prolactinoma may occur in different clinical settings and always require an individually tailored approach. This is the reason why a panel of Italian neuroendocrine experts was charged with the task to provide indications for the diagnostic and therapeutic approaches that can be easily applied in different contexts. The document provides 15 recommendations for diagnosis and 54 recommendations for treatment, issued according to the GRADE system. The level of agreement among panel members was formally evaluated by RAND-UCLA methodology. In the last century, prolactinomas represented the paradigm of pituitary tumors for which the development of highly effective drugs obtained the best results, allowing to avoid neurosurgery in most cases. The impressive improvement of neurosurgical endoscopic techniques allows a far better definition of the tumoral tissue during surgery and the remission of endocrine symptoms in many patients with pituitary tumors. Consequently, this refinement of neurosurgery is changing the therapeutic strategy in prolactinomas, allowing the definitive cure of some patients with permanent discontinuation of medical therapy.

Pituitary tumors and the risk of other malignancies: is the relationship coincidental or causal?

Pituitary adenomas are benign neoplasms of the pituitary. The most prevalent are prolactinomas and non-functioning pituitary adenomas, followed by growth hormone- and ACTH-secreting adenomas. Most pituitary adenomas seem to be sporadic and their persistent growth is very atypical. No molecular markers predict their behavior. The occurrence of pituitary adenomas and malignancies in the same patient can be either pure coincidence or caused by shared underlying genetic susceptibility involved in tumorigenesis. Detailed family history on cancers/tumors in the first, second and third generation of family members on each side of the family has been reported in a few studies. They found an association of pituitary tumors with positive family history for breast, lung and colorectal cancer. We have reported that in about 50% of patients with pituitary adenomas, an association with positive family history for cancer has been found independent of secretory phenotype (acromegaly, prolactinoma, Cushing's disease or non-functioning pituitary adenomas). We also found earlier onset of pituitary tumors (younger age at diagnosis of pituitary tumors) in patients with a strong family history of cancer. In our recent unpublished series of 1300 patients with pituitary adenomas, 6.8% of patients were diagnosed with malignancy. The latency period between the diagnosis of pituitary adenoma and cancer was variable, and in 33% of patients, it was longer than 5 years. Besides the inherited trophic mechanisms (shared underlying genetic variants), the potential influence of shared complex epigenetic influences (environmental and behavioral factors - obesity, smoking, alcohol intake and insulin resistance) is discussed. Further studies are needed to better understand if patients with pituitary adenomas are at increased risk for cancer.

Terminal differentiation and anti-tumorigenic effects of prolactin in breast cancer

Breast cancer is a major disease affecting women worldwide. A woman has 1 in 8 lifetime risk of developing breast cancer, and morbidity and mortality due to this disease are expected to continue to rise globally. Breast cancer remains a challenging disease due to its heterogeneity, propensity for recurrence and metastasis to distant vital organs including bones, lungs, liver and brain ultimately leading to patient death. Despite the development of various therapeutic strategies to treat breast cancer, still there are no effective treatments once metastasis has occurred. Loss of differentiation and increased cellular plasticity and stemness are being recognized molecularly and clinically as major derivers of heterogeneity, tumor evolution, relapse, metastasis, and therapeutic failure. In solid tumors, breast cancer is one of the leading cancer types in which tumor differentiation state has long been known to influence cancer behavior. Reprograming and/or restoring differentiation of cancer cells has been proposed to provide a viable approach to reverse the cancer through differentiation and terminal maturation. The hormone prolactin (PRL) is known to play a critical role in mammary gland lobuloalveolar development/remodeling and the terminal differentiation of the mammary epithelial cells promoting milk proteins gene expression and lactation. Here, we will highlight recent discoveries supporting an anti-tumorigenic role for PRL in breast cancer as a "pro/forward-differentiation" pathway restricting plasticity, stemness and tumorigenesis.

Effect of antipsychotics on breast tumors by analysis of the Japanese Adverse Drug Event Report database and cell-based experiments

Background

Since antipsychotics induce hyperprolactinemia via the dopamine D₂ receptor, long-term administration may be a risk factor for developing breast tumors, including breast cancer. On the other hand, some antipsychotic drugs have been reported to suppress the growth of breast cancer cells in vitro. Thus, it is not clear whether the use of antipsychotics actually increases the risk of developing or exacerbating breast tumors. The purpose of this study was to clarify the effects of antipsychotic drugs on the onset and progression of breast tumors by analyzing an adverse event spontaneous reporting database and evaluating the proliferation ability of breast cancer cells.

Methods

Japanese Adverse Drug Event Report database (JADER) reports from April 2004 to April 2019 were obtained from the Pharmaceuticals and Medical Devices Agency (PMDA) website. Reports of females only were analyzed. Adverse events included in the analysis were hyperprolactinemia and 60 breast tumor-related preferred terms. The reporting odds ratio (ROR), proportional reporting ratio (PRR), and information component (IC) were used to detect signals. Furthermore, MCF-7 cells were treated with haloperidol, risperidone, paliperidone, sulpiride, olanzapine and blonanserin, and cell proliferation was evaluated by WST-8 assay.

Results

In the JADER analysis, the IC signals of hyperprolactinemia were detected with sulpiride (IC, 3.73; 95% CI: 1.81–5.65), risperidone (IC, 3.69; 95% CI: 1.71–5.61), and paliperidone (IC, 4.54; 95% CI: 2.96–6.12). However, the IC signal of breast tumors was not observed with any antipsychotics. In cell-based experiments, MCF-7 cells were treated with six antipsychotics at concentrations of 2 and 32 μM, and none of the drugs showed any growth-promoting effects on MCF-7 cells. On the other hand, blonanserin markedly suppressed the growth of MCF-7 cells at a concentration of 32 μM, and the effect was concentration dependent.

Conclusions

Analysis of the JADER using the IC did not show breast tumor signals due to antipsychotic drugs. In in vitro experiments, antipsychotics did not promote MCF-7 cell proliferation whereas blonanserin suppressed MCF-7 cell growth. Further research on the effects of blonanserin on the onset and progression of breast tumor is expected.

Antipsychotic-induced Hyperprolactinemia in aging populations: Prevalence, implications, prevention and management

This paper reviews the prevalence, implications, prevention and management of antipsychotic-induced hyperprolactinemia in aging populations. Antipsychotics are indicated mainly for the treatment of psychotic illness but are also used in other conditions. Complications induced by antipsychotics increase with age, due to age-related changes in drug metabolism and excretion. Almost all antipsychotics lead to hyperprolactinemia by blocking dopamine D2 receptors in the anterior pituitary gland, which counteracts dopamine's inhibitory action on prolactin secretion. The main findings of this narrative review are that, though many of the known side effects of high prolactin levels lose their salience with age, the risk of exacerbating osteoporosis remains critical. Methods of preventing antipsychotic-induced hyperprolactinemia in older individuals include using antipsychotic medication (AP) as sparingly as possible and monitoring AP serum levels, regularly measuring prolactin levels, closely monitoring bone density, treating substance abuse, and teaching patients stress management techniques. When hyperprolactinemia symptoms cannot be otherwise managed, adjunctive drugs are available. Potential helpful adjuncts are: dopamine agonists, antipsychotics with partial agonist properties (e.g. aripiprazole), selective estrogen receptor modulators, and metformin. Because a gold standard for prevention/treatment has not been established, clinical decisions need to be made based on safety and individual circumstance.

Hyperprolactinaemia in the context of psychiatry

Advocating for good physical healthcare for their patients is of the utmost importance to psychiatrists. This narrative review focuses on one part of this large goal, the topic of hyperprolactinaemia from the perspective of mental healthcare. For psychiatrists this often includes managing raised prolactin levels in the context of medication. However, they must consider the wider differentials of a raised prolactin level and the possible impact of treatments. For that reason, in this review we start with an overview of prolactin physiology before considering hyperprolactinaemia both in the context of antipsychotic therapy and its wider differentials, including prolactinoma. Investigation and management are considered and key practice points developed.

Prolactinomas and menopause: any changes in management?

PURPOSE

Treatment goals in prolactinomas are to correct hypogonadism, restore fertility and control tumor mass in case of macroadenomas. According to current guidelines, medical treatment of asymptomatic postmenopausal women is not indicated. The purpose of this study was to review the current literature pertaining to biological behavior of prolactinomas during menopause, likelihood of successful dopamine agonist withdrawal during this period and possible prolactin-mediated increased morbidity that could modify current management.

METHODS

A comprehensive literature search including papers published until July 2019 was conducted using PubMed and Medline databases.

RESULTS

Women with prolactinomas entering menopause have a higher chance of prolactin normalization of treatment compared with women in their reproductive years. Although most prolactin secreting adenomas diagnosed during menopause are large, they respond well to dopamine agonist treatment. Data directly linking hyperprolactinemia with an increased risk of cancer and cardiovascular and metabolic morbidity are inconsistent. There is no data indicating that correction of hyperprolactinemia improves clinical outcomes in asymptomatic patients bearing microadenomas.

CONCLUSION

There is no evidence that justifies changing current recommendations to withhold medical treatment of microprolactinomas in asymptomatic post-menopausal women. Macroprolactinoma patients should be treated according to standard clinical practice.

Hyperprolactinemia/Prolactinomas in the Postmenopausal Period: Challenges in Diagnosis and Management

Hyperprolactinemia is not a common finding in postmenopausal women. Prolactinomas detected after menopause are usually macroadenomas. Due to atypical clinical features they may remain unrecognized for a long period of time. Interestingly the growth potential of prolactinomas remains after menopause. Most tumors are invasive and present with high prolactin levels. They respond to medical treatment with dopamine agonists in terms of prolactin normalization, tumor shrinkage, and improvement in pituitary function. Treatment with dopamine agonists is usually long term. Reducing doses of cabergoline to the lowest that keeps prolactin levels normal prior to withdrawal is proposed to patients with macroprolactinomas who normalize prolactin after > 5 years of treatment and who do not have cavernous sinus invasion. Cabergoline can achieve a high percentage of remission maintenance in the first years after withdrawal. However, the percentage of relapse-free patients 5 years after withdrawal is significantly lower. Besides recurrent hyper-prolactinemia in a subgroup of macroprolactinomas after a long-interval tumor regrowth may be detected. Menopause cannot ensure remission of the tumor so long-term surveillance is suggested. In patients with microadenomas data on long-term remission rates (normalization of prolactin and disappearance of the tumor) after suspension of treatment with dopamine agonists are highly variable. The current strategy for microprolactinomas is not to treat hyperprolactinemia in menopause if it recurrs after discontinuation of dopamine agonists. This is based on: (1) reports that elevated prolactin levels may normalize in some women after menopause, (2) the fact that the association between prolactin levels and breast cancer is inconsistent in postmenopausal women, (3) the lack of clinical evidence that normalization of prolactin levels in postmenopausal women improves bone mineral density or reduces the risk of fracture, and (4) the fact that, concerning the metabolic syndrome, no data are available on metabolic parameters after suspension of treatment with dopamine agonists. For a change in strategy, i.e., for the potential benefits from treatment of hyperprolactinemia in the postmenopausal period with dopamine agonists concerning weight loss, improved insulin sensitivity, decreased fracture risk, and improved sexuality, more evidence is needed.

Hyperprolactinaemia: A guide for psychiatrists

Medications prescribed by psychiatrists are known to elevate serum prolactin levels, but hyperprolactinaemia remains underrecognised, as the adverse effects of an elevated prolactin are mostly not visible. Hyperprolactinaemia can lead to adverse health outcomes, so clinicians need not only to be alert to its symptoms, but to manage the consequences as well. In this article we provide a brief overview of prolactin physiology, regulation and function. We list various factors that can lead to elevated serum prolactin. We discuss the interpretation of blood results and the management of psychotropic-induced hyperprolactinaemia. We include a flow diagram to assist clinicians in decision-making in the clinical management of hyperprolactinaemia.

Learning Objectives

• Understand prolactin physiology and regulation

• Understand hyperprolactinaemia and its causes

• Know the consequences of hyperprolactinaemia and appropriately manage it in clinical practice

Morbidity and mortality in patients with hyperprolactinaemia: the PROLEARS study

PURPOSE

High serum prolactin concentrations have been associated with adverse health outcomes in some but not all studies. This study aimed to examine the morbidity and all-cause mortality associated with hyperprolactinaemia.

METHODS

A population-based matched cohort study in Tayside (Scotland, UK) from 1988 to 2014 was performed. Record-linkage technology was used to identify patients with hyperprolactinaemia that were compared to an age-sex-matched cohort of patients free of hyperprolactinaemia. The number of deaths and incident admissions with diabetes mellitus, cardiovascular disease, cancer, breast cancer, bone fractures and infectious conditions were compared by the survival analysis.

RESULTS

Patients with hyperprolactinaemia related to pituitary tumours had no increased risk of diabetes, cardiovascular disease, bone fractures, all-cause cancer or breast cancer. Whilst no increased mortality was observed in patients with pituitary microadenomas (HR = 1.65, 95% CI: 0.79-3.44), other subgroups including those with pituitary macroadenomas and drug-induced and idiopathic hyperprolactinaemia demonstrated an increased risk of death. Individuals with drug-induced hyperprolactinaemia also demonstrated increased risks of diabetes, cardiovascular disease, infectious disease and bone fracture. However, these increased risks were not associated with the degree of serum prolactin elevation (P_trend > 0.3). No increased risk of cancer was observed in any subgroup.

CONCLUSIONS

No excess morbidity was observed in patients with raised prolactin due to pituitary tumours. Although the increased morbidity and mortality associated with defined patient subgroups are unlikely to be directly related to the elevation in serum prolactin, hyperprolactinaemia might act as a biomarker for the presence of some increased disease risk in these patients.

Risk of breast cancer in risperidone users: A nationwide cohort study

BACKGROUND

Several antipsychotics, especially risperidone, are known to increase serum prolactin. Hyperprolactinemia has been linked to the development of mammary gland tumors in animal studies. We therefore investigated the risk of breast cancer in a nationwide cohort of women using risperidone or other antipsychotics.

METHODS

All women, 18years or older, who initiated treatment with risperidone or any other antipsychotic between 2006 and 2012 were identified in Swedish nationwide registers. Patients with two consecutive dispensations of the same antipsychotic within 3months, no previous cancer diagnosis, and no previous dispensations of paliperidone were included. The final cohort consisted of 55976 women of whom 22908, 24524, and 8544 were exposed to risperidone, other atypical antipsychotics, and typical antipsychotics, respectively. A Cox regression model was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for the association between antipsychotics and breast cancer.

RESULTS

Patients were followed prospectively, the mean follow-up time ranging from 2.4 to 2.8years between treatment groups. After adjusting for age, there was no increased risk for breast cancer among risperidone users compared to patients exposed to another atypical antipsychotic (HR 0.94, 95% CI 0.72-1.22) or a typical antipsychotic (HR 1.25, 95% CI 0.94-1.66). Analyses stratified by tumor stage, using active treatment follow-up time, or including only treatment naïve patients did not reveal any noteworthy change in the results.

CONCLUSION

Risperidone use does not confer an increased short-term risk of breast cancer compared to other antipsychotic agents.

The epidemiology of hyperprolactinaemia over 20 years in the Tayside region of Scotland: the Prolactin Epidemiology, Audit and Research Study (PROLEARS)

OBJECTIVE

To estimate the prevalence and incidence of hyperprolactinaemia. Hyperprolactinaemia is a common problem in endocrine practice, but its epidemiology has not been accurately established.

STUDY DESIGN

A population-based retrospective follow-up study in Tayside, Scotland (population 400,000), from 1993 to 2013.

PATIENTS

Record linkage technology (biochemistry, prescribing, hospital admissions, radiology, mortality and maternity data) was used to identify all patients with a serum prolactin measurement. From these, cases were defined as those with a prolactin greater than 1000 mU/L (47·2 ng/ml) or at least three prescriptions for a dopamine agonist.

MEASUREMENTS

Number of prevalent and incident cases of hyperprolactinaemia per calendar year by age, sex and cause of hyperprolactinaemia.

RESULTS

A total of 32289 patients had a serum prolactin assay undertaken, of which 1301 had hyperprolactinaemia not related to pregnancy: 25·6% patients had pituitary disorder, 45·9% were drug-induced, 7·5% had macroprolactin and 6·1% had hypothyroidism, leaving 15·0% idiopathic. Over the 20 years, there was a fourfold increase in the number of prolactin assays performed, and prevalence of hyperprolactinaemia was initially 0·02%, but rose to 0·23% by 2013. Overall incidence was 13·8 cases per 100000 person-years (20·6 in 2008-13) and was 3·5 times higher in women than in men. The highest rates were found in women aged 25-44 years. Drug-induced causes tripled during the 20 years.

CONCLUSIONS

Rising prevalence of hyperprolactinaemia is probably due to an increased ascertainment and increased incidence of psychoactive drug-related causes. Rates are higher in women than in men but only before the age of 65 years.