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

Pituitary Diseases and Bone

Neuroendocrinology of bone is a new area of research based on the evidence that pituitary hormones may directly modulate bone remodeling and metabolism. Skeletal fragility associated with high risk of fractures is a common complication of several pituitary diseases such as hypopituitarism, Cushing disease, acromegaly, and hyperprolactinemia. As in other forms of secondary osteoporosis, pituitary diseases generally affect bone quality more than bone quantity, and fractures may occur even in the presence of normal or low-normal bone mineral density as measured by dual-energy X-ray absorptiometry, making difficult the prediction of fractures in these clinical settings. Treatment of pituitary hormone excess and deficiency generally improves skeletal health, although some patients remain at high risk of fractures, and treatment with bone-active drugs may become mandatory. The aim of this review is to discuss the physiological, pathophysiological, and clinical insights of bone involvement in pituitary diseases.

Management of cystic prolactinomas: a review

INTRODUCTION

Cystic prolactinoma is a variant of prolactin-secreting pituitary adenoma. The strategies for the management of cystic prolactinoma have not been addressed thoroughly in clinical guidelines.

METHODS

A literature search was performed using Pubmed to review the current approaches to the treatment of cystic prolactinoma.

RESULTS

Transsphenoidal resection is an effective and relatively safe approach for the treatment of cystic prolactinoma, however, morbidity of surgery is dependent on the skill of the surgeon. Emerging studies allude to the efficacy and safety of dopamine agonists in the management of cystic prolactinoma. Dopamine agonists are associated with considerable rates of clinical improvement and tumor shrinkage, hence reducing the need for surgical intervention.

CONCLUSIONS

Recent studies suggest that dopamine agonist therapy may be an effective and safe treatment option in a considerable portion of patients with cystic prolactinomas. We suggest that dopamine agonists should be considered as a first-line therapy for cystic prolactinoma in the absence of indications for early surgical intervention.

An Evaluation of Reported Follicle-stimulating Hormone, Luteinizing Hormone, Estradiol, and Prolactin Reference Ranges in the United States

OBJECTIVE

To characterize US clinical laboratory reference range reporting and testing methods of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, and prolactin.

METHODS

One hundred and seventeen US laboratories were surveyed. Outcomes measured were variation in lower and upper limits of normal male reference ranges for serum FSH, LH, estradiol, and prolactin, method of analysis and source of reference range RESULTS: The upper limit of normal reference ranges for FSH, LH, estradiol, and prolactin varied substantially across laboratories compared to the lower limits. The range of upper limits of FSH, LH, estradiol, and prolactin respectively are 7.9-20.0, 4.9-86.5, 37.7-77.0, and 7.4-25.0. Ninety-four percent of laboratories performed measurements on in-house high throughput analyzer utilizing immunoassays. Seventy percent of reported reference ranges for each hormone were based on validation studies of the analyzer's package insert values. Ten percent of laboratories derived their own reference ranges. Both the validation studies and derivations were based on a limited number of patient samples, ranging from 20 to 200.

CONCLUSION

Current reference ranges are based on small population studies of men with unknown medical histories, sexual or reproductive function. Influence of race and age has not been evaluated and could potentially be important in normal variation. The absence of standard information has yielded a spectrum of upper and lower normal values, which could delay an appropriate male infertility evaluation. Our findings highlight the need for a large population study of males with known normal sexual and reproductive function to formulate more accurate clinical reference ranges.

The value of prolactin in predicting prolactinοma in hyperprolactinaemic polycystic ovarian syndrome

BACKGROUND

To identify a serum prolactin (PRL) cut-off value indicative of a PRL-producing adenoma in women with polycystic ovarian syndrome (PCOS) and hyperprolactinaemia and characterize such patients.

MATERIALS AND METHODS

In the present retrospective case-control study, the medical records of 528 PCOS women were reviewed. Pituitary magnetic resonance imaging (MRI) was performed in PCOS patients with PRL levels ≥94.0 ng/mL and/or symptoms suspicious of a pituitary adenoma (PA). Prolactinoma diagnosis was made in the presence of an MRI-identifiable PA with biochemical and radiological response to dopamine agonists. Receiver operating characteristic (ROC) curve analysis was performed to determine a serum PRL threshold that could identify hyperprolactinaemic PCOS subjects with prolactinomas. Clinical, metabolic and endocrine parameters were also analysed.

RESULTS

Among 528 patients with PCOS, 60 (11.4%) had elevated PRL levels. Of 44 (73.3%) patients who had pituitary imaging, 19 had PAs, 18 normal MRI and 7 other abnormalities. Patients harbouring prolactinomas had significantly higher PRL levels compared to patients without adenomas (median PRL 95.4 vs 49.2 ng/mL, P < .0001). A PRL threshold of 85.2 ng/mL could distinguish patients with prolactinomas with 77% sensitivity and 100% specificity [Area Under the curve (AUC) (95%) 0.91(0.8-1.018), P = .0001]. PCOS women with prolactinomas were younger and had lower LH levels compared to women without prolactinomas.

CONCLUSIONS

In women with PCOS, PRL levels exceeding 85.2 ng/mL are highly suggestive of a prolactinoma warranting pituitary imaging. Pituitary MRI could also be considered in young PCOS patients with milder PRL elevation and low LH levels.

Complete evaluation of pituitary tumours in a single tertiary care institution

INTRODUCTION

We retrospectively evaluated all patients with pituitary tumours treated in our department from 1/1/1997 to 01/11/2014.

PATIENTS AND METHODS

Two hundred and fifteen patients (124 females, 91 males, mean age 50.9 years) were treated because of pituitary tumours. All patients underwent basal hormonal analysis and when required dynamic testing in order to check for hormonal activity. Pituitary masses were divided into groups concerning their hormonal status and were further classified according to gender, age at diagnosis, tumour size, and the development of postoperative pituitary insufficiency when neurosurgical intervention was conducted.

RESULTS

One hundred and twenty-one patients had hormonally inactive tumours (non-functional adenomas; 56.3%), 57 prolactinomas (26.5%), 17 growth hormone secreting adenomas (7.9%), 16 Cushing's disease (7.4%), and 4 craniopharyngiomas (1.9%). Tumours with maximum size <1 cm (microadenomas) were detected in 62 patients (28.8%) and ≥1 cm (macroadenomas) in 153 (71.2%) of all cases (rate 1:2.5). Ninty eight patients (45.6%) had surgery (87 transsphenoidal and 11 transcranial), of this group 34 with hormonally active tumours (37.8% of the 90 patients of this subcohort). Indications for surgery were an increased risk or manifestation of chiasma syndrome and clinical symptoms due to hormonal hypersecretion. Complete [32 cases (32.6%)] or partial [33 cases (33.7%)] postoperative insufficiency in minimum one pituitary axis was present in 65/98 (66.3%) of the operated patients.

CONCLUSIONS

Pituitary adenoma prevalence is rising due to widely available imaging procedures. The majority of the tumours in our cohort were macroadenomas and hormonally inactive. Tumour extirpation via the transsphenoidal or transcranial route resulted in functional pituitary impairment of variable extent in 2/3 of the patients.

Preoperative Stratification of Transsphenoidal Pituitary Surgery Patients Based on Surgical Urgency

BACKGROUND

Currently, there is no prioritization scale available to distinguish those patients with pituitary tumors who require urgent surgical intervention from those who are candidates for elective treatment.

OBJECTIVE

To develop a classification system that can help primary care physicians, endocrinologists, neurosurgeons, ancillary support staff, and hospital administrators identify high-priority surgical candidates.

METHODS

An expert international panel of clinicians consisting of endocrinologists and neurosurgeons who are involved in the diagnosis and management of sellar disease was convened. The panel retrospectively reviewed individual experiences, including a cohort of patients operated upon for pituitary related disease at the Brigham and Women's Hospital from January 2008 to November 2015. A risk stratification schema was developed to streamline patient care pathways.

RESULTS

We identified 4 groups of surgical candidates with varying levels of risk, and then assigned treatment timelines and different differential diagnoses to each. The 4 groups were as follows: group A: urgent-immediate; group B: prompt-initiate treatment within 1 to 2 weeks; group C: soon-initiate treatment within 3 months; group D: elective-as soon as indicated. Among 472 patients treated at Brigham and Women's Hospital for pituitary adenomas, each was assigned to 1 of the 4 predetermined subgroups: group A, 6.8%; group B, 30.1%; group C, 31.1%; group D, 32.0%.

CONCLUSIONS

We developed a risk stratification schema that may serve as a platform to streamline care to the patients at highest risk. The expert opinions presented provide a basis for future studies regarding the risk prioritization of patients.

Combination Treatment with Bromocriptine and Metformin in Patients with Bromocriptine-Resistant Prolactinomas: Pilot Study

BACKGROUND

Prolactinomas are the most common functional pituitary adenomas and dopamine agonists are the primary therapy. However, some patients are resistant to dopamine agonists. Recently, metformin has been proposed as a cancer treatment.

CASE DESCRIPTION

This study is a retrospective review of 2 cases including 1 patient with prolactinoma who was resistant to bromocriptine, diagnosed with impaired glucose tolerance, and administered metformin. Surprisingly, combining the patient's treatment with metformin decreased prolactin (PRL) levels to 12 ng/mL and significantly decreased the size of the tumor after 1 year of combination therapy. As menstruation resumed and galactorrhea resolved, the patient became pregnant and stopped using metformin but continued taking bromocriptine. She gave birth to a healthy boy in August 2016. After delivery, she decided to breastfeed the baby and only took bromocriptine. After 14 months of using bromocriptine alone, her PRL level increased to 208 ng/mL and the tumor reappeared (7 mm × 8 mm × 9 mm). Interestingly, the patient's PRL level decreased from 208 ng/mL to 150 ng/mL 2 months after using combination treatment with bromocriptine and metformin. On the basis of these findings, a second bromocriptine-resistant patient was recruited. After 3 months of combined treatment with bromocriptine and metformin, the patient's PRL level decreased to 2.08 ng/mL, testosterone levels increased significantly, and the tumor size decreased.

CONCLUSIONS

Although more cases and investigations into the mechanisms underlying these effects are needed, these 2 cases support the hypothesis that the combination of metformin and bromocriptine might be a new treatment for resistant prolactinomas.

Impact of macroprolactin on galactorrhea and the rate of patients possibly affected by macroprolactin

The clinical influence of macroprolactin (MPRL) is not clearly understood and the rate of patients potentially affected by MPRL is unknown. We investigated the influence of MPRL on the onset of galactorrhea and estimated the rate of patients with a proportion of MPRL fraction that may possibly affect galactorrhea. Data of patients with obstetric or gynecological symptoms who had undergone PRL fractionation testing were retrospectively analyzed. To evaluate factors influencing galactorrhea, a multivariate logistic regression analysis was performed and the adjusted odds ratios of MPRL for galactorrhea were calculated. Cutoff values for the total PRL level and the proportion of MPRL fractions for galactorrhea were determined by ROC analysis using a multivariate logistic model. The prevalence of patients with a proportion of MPRL fraction greater than or equal to the cutoff value for galactorrhea was estimated. The median proportion of MPRL fraction was 30.1% and increased as PRL level increased. Total PRL and MPRL had a significant influence on the onset of galactorrhea and the adjusted odds ratio was 1.09 in total PRL and 0.94 in MPRL. The rate of patients with a proportion of MPRL fraction that may possibly affect galactorrhea was estimated to be 33.5% of the study population, and thus found to be twelve times or more the number of macroprolactinemia patients. Future prospects for hyperprolactinemia may require diagnostic criteria using free prolactin levels and so MPRL fraction measurement is important for the diagnosis and treatment of patients with obstetric and gynecological symptoms.

Cognitive Function and Serum Hormone Levels Are Associated with Gray Matter Volume Decline in Female Patients with Prolactinomas

Background and objective

Cognitive impairments have been reported in patients with hyperprolactinemia; however, there is a lack of knowledge of brain structure alterations relevant to hyperprolactinemia in prolactinomas. Thus, we aimed to identify changes in brain structure in prolactinomas and to determine whether these changes are related to cognitive performance and clinical characteristics.

Methods

Participants were 32 female patients with prolactinomas and 26 healthy controls (HC) matched for age, sex, education, and handedness. All participants underwent magnetic resonance imaging brain scans, neuropsychological assessments, and clinical evaluations. Voxel-based morphometry analysis was used to identify changes in gray matter volume (GMV). Partial correlation analysis and multiple linear regression were performed to determine the relationship between GMV, cognition, and clinical characteristics.

Results

Compared to HC, patients with prolactinomas demonstrated a decrease in GMV in the left hippocampus, left orbitofrontal cortex, right middle frontal cortex (MFC), and right inferior frontal cortex (IFC). In addition, patients performed worse than controls on tests for verbal memory and executive function, and this was significantly related to the GMV of the left hippocampus and right MFC, respectively. Moreover, in the patients, we found a negative relationship between serum prolactin levels and the GMV of the left hippocampus and right IFC, whereas a positive relationship was found between the GMV of the left hippocampus and serum levels of estradiol and luteinizing hormone.

Conclusion

In patients with prolactinomas, specific brain structure abnormalities have been identified and are associated with cognitive impairments and dysfunctional hormones. This study enhances our understanding of brain structure changes that may occur with prolactinomas and provides novel and fundamental evidence for previous behavioral findings relevant to hyperprolactinemia.

Pediatric Pituitary Adenoma: Case Series, Review of the Literature, and a Skull Base Treatment Paradigm

Background  Pediatric pituitary adenoma is a rare skull base neoplasm, accounting for 3% of all intracranial neoplasms in children and 5% of pituitary adenomas. Compared with pituitary tumors in adults, secreting tumors predominate and longer disease trajectories are expected due to the patient age resulting in a natural history and treatment paradigm that is complex and controversial. Objectives  The aims of this study were to describe a large, single-institution series of pediatric pituitary adenomas with extensive long-term follow-up and to conduct a systematic review examining outcomes after pituitary adenoma surgery in the pediatric population. Methods  The study cohort was compiled by searching institutional pathology and operative reports using diagnosis and site codes for pituitary and sellar pathology, from 1956 to 2016. Systematic review of the English language literature since 1970 was conducted using PubMed, MEDLINE, Embase, and Google Scholar. Results  Thirty-nine surgically managed pediatric pituitary adenomas were identified, including 15 prolactinomas, 14 corticotrophs, 7 somatotrophs, and 4 non-secreting adenomas. All patients underwent transsphenoidal resection (TSR) as the initial surgical treatment. Surgical cure was achieved in 18 (46%); 21 experienced recurrent/persistent disease, with secondary treatments including repeat surgery in 10, radiation in 14, adjuvant pharmacotherapy in 11, and bilateral adrenalectomy in 3. At the last follow-up (median 87 months, range 3-581), nine remained with recurrent/persistent disease (23%). Thirty-seven publications reporting surgical series of pediatric pituitary adenomas were included, containing 1,284 patients. Adrenocorticotropic hormone (ACTH)-secreting tumors were most prevalent (43%), followed by prolactin (PRL)-secreting (37%), growth hormone (GH)-secreting (12%), and nonsecreting (7%). Surgical cure was reported in 65%. Complications included pituitary insufficiency (23%), permanent visual dysfunction (6%), chronic diabetes insipidus (DI) (3%), and postoperative cerebrospinal fluid (CSF) leak (4%). Mean follow-up was 63 months (range 0-240), with recurrent/persistent disease reported in 18% at the time of last follow-up. Conclusion  Pediatric pituitary adenomas are diverse and challenging tumors with complexities far beyond those encountered in the management of routine adult pituitary disease, including nuanced decision-making, a technically demanding operative environment, high propensity for recurrence, and the potentially serious consequences of hypopituitarism with respect to fertility and growth potential in a pediatric population. Optimal treatment requires a high degree of individualization, and patients are most likely to benefit from consolidated, multidisciplinary care in highly experienced centers.

Medical versus surgical treatment of prolactinomas: an analysis of treatment outcomes

INTRODUCTION

Prolactinomas are unique tumors that may go into both hormonal and radiographic remission with dopamine agonist therapy or transsphenoidal surgery. Regardless of modality, the goals of therapy remain the same: (1) biochemical remission, including reduction of prolactin and normalization of sex hormones; (2) radiographic tumor control, with a range including prevention of tumor growth, tumor regression, or complete tumor resolution; (3) resolution of preoperative symptoms, including those that are hormonal or neurologic; and (4) prevention of new hypopituitarism or new neurologic symptoms.

AREAS COVERED

In the following review, we performed a search of the literature using keywords 'prolactinoma,' 'dopamine agonist,' 'surgery,' 'cost-effectiveness,' 'recurrence,' and 'complication' to compare the relative merits of medical versus surgical therapy for prolactinoma, including special circumstances such as cystic tumors, pregnant patients, and the cost-effectiveness of different strategies.

EXPERT COMMENTARY

Medical therapy can offer a cure, but surgery provides an important adjunct to patients with resistance or intolerance to dopamine agonists, and offers excellent outcomes including when combined with continued postoperative medical therapy. Further head to head comparisons will benefit patients and practitioners weighing the relative risks and benefits of medical and surgical intervention, including the issue of their relative cost-effectiveness.

Prolactinoma through the female life cycle

Prolactinomas are the most common secretory pituitary adenoma. They typically occur in women in the 3rd-6th decade of life and rarely in the pediatric population or after menopause. Most women present with irregular menses and/or infertility. Dopamine (DA) agonists, used in their treatment, are safe during pregnancy, but in most cases are discontinued at conception with close monitoring for signs or symptoms of tumor growth. Breastfeeding is safe postpartum, provided there was no significant growth during pregnancy. Some women will experience normalization of prolactin levels postpartum. Menopause may also decrease prolactin levels and even those with macroprolactinomas may consider discontinuing their DA agonist with close follow-up. Prolactinomas may be associated with decreased quality of life scores in women, and play a role in bone health and cardiovascular risk factors. This review discusses the current literature and clinical understanding of prolactinomas throughout the entirety of the female life cycle.

Optimal timing of dopamine agonist withdrawal in patients with hyperprolactinemia: a systematic review and meta-analysis

PURPOSE

Dopamine agonists (DAs) are recommended as first-line treatment for patients with hyperprolactinemia. Generally, it is accepted that patients with hyperprolactinemia do not need lifelong medication, but the optimal timing for DA withdrawal has not been determined. The aim of this systematic review and meta-analysis is to assess the impact of DA withdrawal on the clinical outcomes of patients with hyperprolactinemia, and to explore possible factors affecting successful DA withdrawal.

METHODS

The databases of PubMed, Cochrane and EMBASE were searched up to May 2016.

RESULTS

The proportion of patients with persisting normoprolactinemia after DA withdrawal reached 36.6% in a random effects model (95% CI, 29.4-44.2%; I-squared: 82.5%). Data of stratified analysis showed that the success rate of drug withdrawal was high in patients using cabergoline (CAB) as the only treatment (41.2%; 95% CI 32.3-50.4%) and those using CAB over 24 months (48.7%; 95% CI 38.9-58.5%), especially in patients with idiopathic hyperprolactinemia (73.2%; 95% CI 55.6-87.7%). In addition, patients who received a low maintenance dose of CAB, and had a significant reduction in tumor size (over 50%) before withdrawal, were more likely to achieve success (51.5 and 49.4%, respectively).

CONCLUSION

The success rate of DA withdrawal has increased in recent years. Further, the success rate of CAB withdrawal was higher than that of bromocriptine, especially in patients with a duration of treatment longer than 24 months. Conclusively, the probability of success was higher in patients who received low-dose CAB maintenance treatment and those who achieved a significant reduction in tumor size before withdrawal.

The Mechanism and Pathways of Dopamine and Dopamine Agonists in Prolactinomas

Dopamine agonists such as bromocriptine and cabergoline are the predominant treatment drugs for prolactinoma by inhibiting prolactin secretion and shrinking tumor size. However, the pathways of either dopamine or its agonists that lead to the death of cells are incompletely understood and some are even conflicting conclusions. The main aim of this paper is to review the different pathways of dopamine and its agonists in prolactinomas to help to gain a better understanding of their functions and drug resistance mechanisms.

The Chance of Permanent Cure for Micro- and Macroprolactinomas, Medication or Surgery? A Systematic Review and Meta-Analysis

Background: This meta-analysis aims to evaluate the long-term efficacy of medication treatment vs. surgery treatment in patients with prolactinomas. Methods: An electronic literature search was performed using MEDLINE, EMBASE and Web of Science databases for studies dated before July in 2018. Patients with prolactinomas received primary dopamine agonists (DAs) treatment or primary surgical interventions were included in this study. A systematic review and meta-analysis were performed in pertinent studies meeting eligible criteria. The clinical outcome was measured by the long-term remission rate of prolactin (PRL) in each cohort. The pooled data was analyzed according to a random effect model. Results: Thirteen publications with total 809 patients were included in the final meta-analysis. In the overall patients with prolactinomas, long-term remission rate was achieved in 88% patients treated with surgeries and in 52% patients treated with DAs (P = 0.001). The long-term remission rates in surgery cohort were also significantly higher than medication cohort in both microprolactinomas and macroprolactinomas (91 vs. 60%, P = 0.002; 77 vs. 43%, P = 0.003). Conclusions: Patients with prolactinomas, especially microprolactinomas, can consider transsphenoidal surgery as an alternative first-line treatment strategy. After receiving primary surgical intervention, administration of DAs should be considered based on the postoperative PRL level to achieve the best long-term remission rate.

Antipsychotic-induced hyperprolactinaemia: case studies and review

Antipsychotics are a known cause of hyperprolactinaemia and can be associated with significant health issues in short term and long term. The effects vary with gender and age of the individual and can contribute towards non-concordance and hence relapse in mental health of our patients. Clinicians need to educate the patients about this significant side effect of not only antipsychotic medications but other medications causing hyperprolactinaemia commonly prescribed in primary care.

Criteria for the definition of Pituitary Tumor Centers of Excellence (PTCOE): A Pituitary Society Statement

INTRODUCTION

With the goal of generate uniform criteria among centers dealing with pituitary tumors and to enhance patient care, the Pituitary Society decided to generate criteria for developing Pituitary Tumors Centers of Excellence (PTCOE).

METHODS

To develop that task, a group of ten experts served as a Task Force and through two years of iterative work an initial draft was elaborated. This draft was discussed, modified and finally approved by the Board of Directors of the Pituitary Society. Such document was presented and debated at a specific session of the Congress of the Pituitary Society, Orlando 2017, and suggestions were incorporated. Finally the document was distributed to a large group of global experts that introduced further modifications with final endorsement.

RESULTS

After five years of iterative work a document with the ideal criteria for a PTCOE is presented.

CONCLUSIONS

Acknowledging that very few centers in the world, if any, likely fulfill the requirements here presented, the document may be a tool to guide improvements of care delivery to patients with pituitary disorders. All these criteria must be accommodated to the regulations and organization of Health of a given country.

Best candidates for dopamine agonist withdrawal in patients with prolactinomas

PURPOSE

Dopamine agonist (DA) therapy is recommended as the first-line treatment for prolactinomas. However, it requires long treatment duration, and a high recurrence rate after DA withdrawal has been reported. We aimed to elucidate the predictors for long-term remission following DA withdrawal and propose the best candidates who can achieve complete remission after DA withdrawal.

METHODS

In a retrospective cohort study, we included 89 patients with prolactinoma who have withdrawn DAs with normal prolactin (PRL) levels at Seoul National University Hospital, from 2000 to 2016. Patient's data were retrieved from the electronic medical records.

RESULTS

The median age and median treatment duration of the study patients were 33 (15-73) years and 69.5 (8.3-277.4) months, respectively. The recurrence rate after drug withdrawal was 57.3% during the 23.9 (3.0-176.8) month follow-up period. Age, gender, baseline PRL level, and baseline maximum tumor diameter were similar between the remission and recurrence group. In the Cox-proportional hazard model analysis, the significant predictors for remission were nadir PRL level of <1 ng/dL (hazard ratio [95% confidence interval] = 0.37 [0.18-0.74]), invisible tumors on magnetic resonance imaging (MRI) (0.42 [0.24-0.74]), and treatment duration of >72 months (0.54 [0.30-0.96]). Of the subjects who met all the three criteria, 66.7% achieved long-term remission.

CONCLUSIONS

Patients who have no tumor visible on MRI, have a nadir PRL level <1 ng/dL during drug treatment, and received drug treatment for >6 years may be the best candidates for DA withdrawal.

Autoimmune hypothyroidism is three times more frequent in female prolactinoma patients compared to healthy women: data from a cross-sectional case-control study

BACKGROUND

The potent immunomodulatory action of prolactin has been demonstrated in many experimental in vitro studies. In accordance with these data, our retrospective analyses revealed higher prevalence of autoimmune thyroid diseases in prolactinoma patients compared to general population.

PURPOSE

A cross-sectional case-control study was carried out in a single tertiary referral centre. The main aim was to assess the frequency of newly diagnosed autoimmune thyroid diseases in female patients with prolactinomas.

METHODS

The study population consisted of 260 females (154 patients and 106 sex-matched, ethnicity-matched, and age-matched healthy controls) enroled in a prospective manner. Physical exam, thyroid ultrasound, and laboratory testing (measurement of antibodies to thyroglobulin, thyroid peroxidase, TSH-receptor, serum TSH and FT4 levels) were performed in all study participants.

RESULTS

Autoimmune thyroid diseases were diagnosed in 29.9% of the patients and 10.4% of the healthy subjects (p  = 0.0002). Subclinical hypothyroidism was found in 9.7% of the patients versus 2.8% of the controls (p  = 0.044). Autoimmune hyperthyroidism was observed in 1.3% of all patients.

CONCLUSIONS

The prevalence of newly diagnosed autoimmune thyroid diseases, and especially the subclinical hypothyroidism, was significantly higher in our female prolactinoma patients in comparison to age-matched healthy women. Based on our results, we suggest routine screening for autoimmune thyroid diseases (thyroid function, immunology and ultrasound examination) in all female patients with prolactinoma at the time of diagnosis. We also recommend a close follow-up of thyroid function in these women in case of pregnancy and after delivery.

Reoperative endoscopic endonasal surgery for residual or recurrent pituitary adenomas

OBJECTIVE

Regrowth of the lesion after surgical removal of pituitary adenomas is uncommon unless subtotal resection was originally achieved in the first surgery. Treatment for recurrent tumor can involve surgery or radiotherapy. Locations of residual tumor may vary based on the original approach. The authors evaluated the specific sites of residual or recurrent tumor after different transsphenoidal approaches and describe the surgical outcome of endoscopic endonasal transsphenoidal reoperation.

METHODS

The authors analyzed a prospectively collected database of a consecutive series of patients who had undergone endoscopic endonasal surgeries for residual or recurrent pituitary adenomas after an original transsphenoidal microscopic or endoscopic surgery. The site of the recurrent tumor and outcome after reoperation were noted and correlated with the primary surgical approach. The chi-square or Fisher exact test was used to compare categorical variables, and the Mann-Whitney U-test was used to compare continuous variables between surgical groups.

RESULTS

Forty-one patients underwent surgery for residual/recurrent pituitary adenoma from 2004 to 2015 at Weill Cornell Medical College. The previous treatment was a transsphenoidal microscopic (n = 22) and endoscopic endonasal (n = 19) surgery. In 83.3% patients (n = 30/36) there was postoperative residual tumor after the initial surgery. A residual tumor following endonasal endoscopic surgery was less common in the sphenoid sinus (10.5%; 2/19) than it was after microscopic transsphenoidal surgery (72.7%; n =16/22; p = 0.004). Gross-total resection (GTR) was achieved in 58.5%, and either GTR or near-total resection was achieved in 92.7%. Across all cases, the average extent of resection was 93.7%. The rate of GTR was lower in patients with Knosp-Steiner Grade 3–4 invasion (p < 0.0005). Postoperative CSF leak was seen in only one case (2.4%), which stopped with lumbar drainage. Visual fields improved in 52.9% (n = 9/17) of patients and were stable in 47% (n = 8/17). Endocrine remission was achieved in 77.8% (n = 14/18) of cases, 12 by surgery alone and 2 by adjuvant medical (n = 1) and radiation (n = 1) therapy. New diabetes insipidus occurred in 4.9% (n = 2/41) of patients—in one of whom an additional single anterior hormonal axis was compromised—and 9.7% (n = 4/41) of patients had a new anterior pituitary hormonal insufficiency.

CONCLUSIONS

Endonasal endoscopic reoperation is extremely effective at removing recurrent or residual pituitary adenomas that remain after a prior surgery, and it may be preferable to radiation therapy particularly in symptomatic patients. Achievement of GTR is less common when lateral cavernous sinus invasion is present. The locations of residual/recurrent tumor were more likely sphenoidal and parasellar following a prior microscopic transsphenoidal surgery and sellar following a prior endonasal endoscopic surgery.

Prolactinoma management: predictors of remission and recurrence after dopamine agonists withdrawal

OBJECTIVE

Prolactinomas are the most common functional pituitary tumour. Dopamine agonists (DA) are its principal treatment. The criteria that should guide therapy withdrawal and the factors that influence disease remission or relapse are not yet fully established. Our purpose is to evaluate the proportion of patients who attempted DA withdrawal, and to identify the factors that influence clinicians to try it. In addition, we aim to study the factors that are involved in prolactinoma remission/relapse after therapy withdrawal.

METHODS

We retrospectively evaluated 142 patients with prolactinoma diagnosis who had been treated exclusively with DA. Firstly, the patients were divided in two groups, according to whether DA withdrawal had been attempted, or not, and the factors that might predict clinicians' decision to discontinue the therapy were then analysed. Secondly, patients who attempted withdrawal were further divided into two subgroups, based on their remission or relapse status and predictors of remission were evaluated.

RESULTS

DA withdrawal was attempted in 35.2% of our patients. Females, subjects with lower initial serum prolactin (PRL) levels, those with microadenomas and those with longer treatment duration all had a higher probability of seeing their therapy discontinued. In the withdrawal group, the remission rate was 72%. Macroprolactinomas relapse more often than microprolactinomas (p < 0.05). The recurrence group had higher median initial serum PRL levels and a lower mean duration of therapy, however these variables did not reach statistical significance.

CONCLUSION

We found a low percentage of attempt of withdrawal of DA therapy in the subjects with prolactinoma. Our data confirms that DA therapy can be discontinued with a high remission rate. Tumour size was the main variable that affected the withdrawal outcome in our patients.

The Role of p16 and MDM2 Gene Polymorphisms in Prolactinoma: MDM2 Gene Polymorphisms May Be Associated with Tumor Shrinkage

AIM

Prolactinomas are thought to arise from clonal expansion of a single mutated cell which is subjected to growth stimuli of several permissive factors, although the pathogenetic mechanisms underlying tumorigenesis remain unclear. The present study aimed to investigate the role of p16 (540C→G and 580C→T) and mouse double minute 2 (MDM2) (SNP309T→G) gene polymorphisms in tumorigenesis and characteristics of prolactinoma.

PATIENTS AND METHODS

A total of 74 patients with prolactinoma and 100 age- and gender-matched healthy individuals were enrolled in the study. Serum prolactin levels were measured by enzyme-linked immunosorbent assay (ELISA). p16 and MDM2 polymorphisms were determined by polymerase chain reaction-restriction fragment polymorphism and agarose gel electrophoresis.

RESULTS

p16 540C→G genotype distribution was found to be: CC: 66.2%, CG: 28.4%, GG: 5.4%; p16 580C→T genotype distribution was found to be: CC: 82.4%, CT: 17.6%, TT: 0% and MDM2 genotype distribution was found to be: TT: 31.1%, TG: 47.3%, GG: 21.6% in patients with prolactinoma. Tumor diameter before treatment was correlated with prolactin levels before treatment and percentage of prolactin decrease with treatment (r=0.719, p<0.001, p=0.034 r=0.256, respectively). The number of patients with tumor size decrease of more than 50% in those with homozygous genotype (TT+GG) of MDM2 SNP309T→G was significantly higher than in heterozygous genotype (TG) carriers (odds ratio(OR)=0.18, 95% confidence interval(CI)=0.06-0.58; p=0.003).

CONCLUSION

This study showed that p16 and MDM2 polymorphisms do not play a decisive role in tumorigenesis, but some genotypes of these polymorphisms might be associated with follow-up characteristics of prolactinoma.

Hyperprolactinaemia - a problem in patients from the reproductive period to the menopause

Hyperprolactinaemia especially affects women in reproductive age (90/100,000) but also often is diagnosed in menopause age and leads to disturbances in functioning of LH-RH neurons and, as a consequence, to a decrease of FSH and LH, which causes inhibition of oestradiol production. Prolactin is a peptide hormone, phylogenetically one of the oldest, stimulating cells of various organs, which is produced and secreted mainly by lactotrophic acidophilic cells of the anterior lobe of the pituitary. It influences the increase in the mass of the mammary glands, and stimulation and maintenance of lactation after delivery. There are a number of factors apart of pregnancy, delivery, and lactation than can influence secretion of the hormone in other physiological and pathological circumstances, like high-protein diet, stress, REM sleep, or neoplastic tumours, inflammatory diseases, chronic systematic diseases, thyroid hormonal changes, and drug intake. The purpose of this review is to summarise the current knowledge regarding the proper diagnosis and possible influence of hyperprolactinaemia on fertility and menopause symptoms and current treatment methods.

Significance of surgical management for cystic prolactinoma

PURPOSE

It is generally accepted that dopamine agonists (DA) represent the first-line treatment for most patients with prolactinoma, and patients become candidates for surgical intervention when DA is contraindicated. Surgical indication for cystic prolactinoma remains controversial. This study was performed to investigate the significance of surgery for cystic prolactinoma.

METHODS

A total of 28 patients that underwent transsphenoidal resection of prolactinoma between February 2004 and May 2016 were reviewed. Five consecutive patients with cystic prolactinoma were included in this study. Our surgical strategy for cystic prolactinoma was categorized as follows: first, when the purpose of surgical resection was normalization of the prolactin level, aggressive resection was performed; second, when volume reduction was essential to relieve the visual symptoms and headache, internal decompression was performed followed by DA therapy. The clinical outcomes were analyzed accordingly.

RESULTS

All cystic prolactinoma were resected via the transsphenoidal approach without any complications, and all symptoms including visual impairment and hypogonadal activity were finally relieved combined with medication.

CONCLUSIONS

Surgery for cystic prolactinoma could be a better option. Transsphenoidal surgery is relatively safe to remove the cystic prolactinoma, additionally it can normalize the prolactine level and achieve adequate and rapid decompression of optic chiasm. The risk of transsphenoidal surgery is highly dependent on the skill of the surgeon and treatment decision for cystic prolactinoma needs to be individualized for each patient.

Management of prolactinomas: a survey of physicians from the Middle East and North Africa

BACKGROUND

Prolactinomas are the commonest functional tumors of the pituitary gland. There are still controversies regarding medical therapy in specific clinical situations. Patients may be managed by different specialists in the Middle East and North Africa (MENA) region and no data exist on patterns of clinical management.

OBJECTIVES

To ascertain the diagnostic and therapeutic approaches to prolactinomas among relevant professionals from the MENA region.

METHODS

An online survey of a large sample of physicians was conducted. The questionnaire covered various aspects of diagnosis and treatment of prolactinomas. 468 respondents were included; 36 % were endocrinologists; 49 % worked in public facilities and 81 % graduated more than 10 years. 40 and 30 % would have seen 1-5 and more than 5 suspected or confirmed prolactinomas over a 6 months period, respectively.

RESULTS

Regarding the diagnosis, 30 % of the respondents considered that prolactin levels <100 ng/ml exclude the presence of a prolactinoma. 21 % of respondents considered prolactin levels >250 ng/ml compatible with macroprolactinomas only, whereas others accepted this to be compatible also with microprolactinomas, macroprolactinaemia and drug-induced hyperprolactinemia (50, 42 and 36 % respectively). 71 % of respondents favored the screening for macroprolactin in asymptomatic individuals with hyperprolactinemia. Regarding the treatment, 84 % of respondents would treat microprolactinomas even in the absence of symptoms whereas 72 % of the respondents would treat microprolactinomas only if symptoms exist. 60 and 49 % of the respondents chose cabergoline as the drug of choice to treat macroprolactinomas and microprolactinomas respectively. Similar proportions had no preference of either cabergoline or bromocriptine as the best treatment for macroprolactinoma (27 %) and microprolactinomas (32 %). 46 and 75 % of respondents favored treatment withdrawal 2-3 years after prolactin normalization in patients with macroprolactinomas and microprolactinomas, respectively whereas 10 % of respondents withdraw treatment after menopause in either case. 94 % of respondents considered medical therapy as the primary treatment for microprolactinomas. In case of pregnancy, 49 % considered bromocriptine as the drug of choice for women who wish to become pregnant. 65 and 38 % of respondents advocated discontinuation of treatment with dopamine agonists in patients with microprolactinomas and macroprolactinomas, respectively. Finally, 48 % would allow breast-feeding without restriction, 28 % would restrict it to patients with microprolactinomas and 25 % would not recommend it for women with prolactinomas.

CONCLUSIONS

This is the first study of the clinical management of prolactinomas in the MENA region. Some of the practices are not in line with the latest Endocrine and Pituitary Societies guidelines. These warrant further discussions of contemporary guidelines in regional forums.

MRI follow-up is unnecessary in patients with macroprolactinomas and long-term normal prolactin levels on dopamine agonist treatment

OBJECTIVE

Both antitumor and antisecretory efficacies of dopamine agonists (DA) make them the first-line treatment of macroprolactinomas. However, there is no guideline for MRI follow-up once prolactin is controlled. The aim of our study was to determine whether a regular MRI follow-up was necessary in patients with long-term normal prolactin levels under DA.

PATIENTS AND METHODS

We conducted a retrospective multicenter study (Marseille, Paris La Pitie Salpetriere and Nancy, France; Liege, Belgium) including patients with macroprolactinomas (largest diameter: >10 mm and baseline prolactin level: >100 ng/mL) treated by dopamine agonists, and regularly followed (pituitary MRI and prolactin levels) during at least 48 months once normal prolactin level was obtained.

RESULTS

In total, 115 patients were included (63 men and 52 women; mean age at diagnosis: 36.3 years). Mean baseline prolactin level was 2224 ± 6839 ng/mL. No significant increase of tumor volume was observed during the follow-up. Of the 21 patients (18%) who presented asymptomatic hemorrhagic changes of the macroprolactinoma on MRI, 2 had a tumor increase (2 and 7 mm in the largest size). Both were treated by cabergoline (1 mg/week) with normal prolactin levels obtained for 6 and 24 months. For both patients, no further growth was observed on MRI during follow-up at the same dose of cabergoline.

CONCLUSION

No significant increase of tumor size was observed in our patients with controlled prolactin levels on DA. MRI follow-up thus appears unnecessary in patients with biologically controlled macroprolactinomas.

Cabergoline Tapering Is Almost Always Successful in Patients With Macroprolactinomas

Context:

Cabergoline (CAB) is very effective in the treatment of macroprolactinomas, but there are few data on the CAB dose necessary to achieve and maintain normal prolactin (PRL) levels.

Design and Patients:

We retrospectively studied 260 patients. CAB was introduced at a mean dose of 0.83 ± 0.52 mg/wk. When the PRL level had normalized, the patient's physician chose to either maintain the CAB dose (fixed-dose group) or to taper it (de-escalation group) until the minimal effective dose required to maintain a normal PRL level was established.

Results:

PRL normalized in 157 patients (60.8%) during CAB treatment. CAB de-escalation was attempted in 84 (53.5%) of these 157 patients and was successful in 77 (91.7%) cases. The mean CAB dose was reduced from 1.52 ± 1.17 mg/wk to 0.56 ± 0.44 mg/wk at the last visit (P < 1 × 10⁻⁴). De-escalation was also possible in some “CAB-resistant” patients, namely those requiring ≥2 mg/wk to normalize PRL. CAB de-escalation had no negative long-term effect on tumor size. At the last visit, maximal diameter was 8.8 ± 8.8 mm in the de-escalation group and 13.4 ± 8.5 mm in the fixed-dose group (P < 0.01).

Conclusion:

In patients with macroprolactinomas, the CAB dosage required to maintain a normal PRL level long term is lower than the initial dosage necessary to normalize the PRL level. After PRL normalization, CAB tapering was almost always successful, even when very high initial doses were necessary. CAB tapering does not undermine tumor control and may attenuate the potential adverse effects of CAB, which appear to be dependent on the cumulative dose.

Establishing reference intervals for sex hormones on the analytical platforms Advia Centaur and Immulite 2000XP

Reliable reference intervals for sex hormones are indispensable in evaluations of the hypothalamo-pituitary-gonadal axis. This study established reference intervals for estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, and prolactin with the immunoassay platforms Advia Centaur and Immulite 2000XP (Siemens Healthcare, Germany). We recruited healthy men (n=220), women in the follicular (n=139) or luteal (n=87) phases of the menstrual cycle, and postmenopausal women (n=103). Data was analyzed according to CLSI EP28-A3c guidelines. Although reference intervals established with both platforms showed good agreement with ranges quoted by the assay manufacturer, two discrepancies were noted. First, intervals for prolactin in women were influenced by hormonal status, and the partition analysis supported their separation into subgroups based on menstrual cycle. Second, the upper limit for estradiol in the follicular phase was nearly a half of that provided by the manufacturer. This discrepancy was attributed to the stringent definition of the follicular phase (consistently set at days 3-5 after menstruation onset). Our findings suggest that reference values for prolactin should both be gender specific and account for menstrual cycle phase. The results also emphasize that clear-cut selection criteria are required when assembling populations for establishing endocrine reference intervals.

Global expression profile of tumor stem-like cells isolated from MMQ rat prolactinoma cell

BACKGROUND

Cancer stem cells (CSCs), which have been isolated from various malignancies, were closely correlated with the occurrence, progression, metastasis and recurrence of the malignant cancer. Little is known about the tumor stem-like cells (TSLCs) isolated from benign tumors. Here we want to explore the global expression profile of RNA of tumor stem-like cells isolated from MMQ rat prolactinoma cells.

METHODS

In this study, total RNA was extracted from MMQ cells and MMQ tumor stem-like cells. RNA expression profiles were determined by Agilent Rat 8 × 60 K Microarray. Then we used the qRT-PCR to test the result of Microarray, and found VEGFA had a distinct pattern of expression in MMQ tumor stem-like cells. Then WB and ELISA were used to confirm the VEGFA protein level of tumor sphere cultured from both MMQ cell and human prolactinoma cell. Finally, CCK-8 was used to evaluate the reaction of MMQ tumor stem-like cells to small interfering RNAs intervention and bevacizumab treatment.

RESULT

The results of Microarray showed that 566 known RNA were over-expressed and 532 known RNA were low-expressed in the MMQ tumor stem-like cells. These genes were mainly involved in 15 different signaling pathways. In pathway in cancer and cell cycle, Bcl2, VEGFA, PTEN, Jun, Fos, APC2 were up-regulated and Ccna2, Cdc25a, Mcm3, Mcm6, Ccnb2, Mcm5, Cdk1, Gadd45a, Myc were down-regulated in the MMQ tumor stem-like cells. The expression of VEGFA were high in tumor spheres cultured from both MMQ cell and human prolactinomas. Down-regulation of VEGFA by small interfering RNAs partially decreased cell viability of MMQ tumor stem-like cells in vitro. Bevacizumab partially suppressed the proliferation of MMQ tumor stem-like cells.

CONCLUSIONS

Our findings characterize the pattern of RNA expression of tumor stem-like cells isolated from MMQ cells. VEGFA may act as a potential therapeutic target for tumor stem-like cells of prolactinomas.

Suppression of mTOR pathway and induction of autophagy-dependent cell death by cabergoline

Cabergoline (CAB), the first-line drug for treatment of prolactinomas, is effective in suppressing prolactin hypersecretion, reducing tumor size, and restoring gonadal function. However, mechanisms for CAB-mediated tumor shrinkage are largely unknown. Here we report a novel cytotoxic mechanism for CAB. CAB induced formation of autophagosome in rat pituitary tumor MMQ and GH3 cells at the early stage through inhibiting mTOR pathway, resulting in higher conversion rates of LC3-I to LC3-II, GFP-LC3 aggregation, and increased autophagosome formation. Interestingly, CAB treatment augmented lysosome acidification and resulted in impaired proteolytic degradation within autolysosomes. This blocked the autophagic flux, leading to the accumulation of p62 aggregation and undigested autolysosomes. Knockdown of ATG7, ATG5, or Becn1, could significantly rescue the CAB-mediated cell death of MMQ cells (p < 0.05). CAB-induced autophagy and blockade of autophagy flux participated in antitumoral action in vivo. In conclusion, our study provides evidence that CAB concomitantly induces autophagy and inhibits the autophagic flux, leading to autophagy-dependent cell death. These findings elucidate novel mechanisms for CAB action.

Successful treatment of a child with a prolactin secreting macroadenoma with temozolomide

Prolactinomas are a rare subset of brain tumors in pediatrics. We report a child with a prolactin secreting macroadenoma which was refractory to initial treatment with a dopamine antagonist. Given the location of her tumor she was ineligible for surgical resection. Temozolomide (200 mg/m2×5 days each month) was administered with a dramatic and prolonged response in tumor size, prolactin level, and symptoms, with no side effects from treatment. We demonstrate the benefit of temozolomide in the treatment of a pediatric patient with prolactinoma.

Recurrence of hyperprolactinemia following dopamine agonist withdrawal and possible predictive factors of recurrence in prolactinomas

BACKGROUND

The optimal duration of cabergoline (CAB) treatment of prolactinomas that minimizes recurrences is not well established. 2011 Endocrine Society Guidelines suggested that withdrawal may be safely undertaken after 2 years in patients achieving normoprolactinemia and tumor reduction.

MATERIALS

We analyzed 74 patients (mean age = 46.9 ± 14.4, M/F = 19/55, macro/micro = 18/56) bearing a prolactinoma divided in 3 groups: group A (23) treated for 3 years, group B (23) for a period between 3 and 5 years, and group C (28) for a period >5 years. CAB therapy was interrupted according to Endocrine Society Guidelines. Prolactin (PRL) levels were measured 3, 6, 12 and 24 months after withdrawal. Recurrence was defined with PRL levels ≥30 ng/ml.

RESULTS

Groups did not differ in pretreatment PRL levels (123.2 ± 112.1, 120.9 ± 123.8, 176.6 ± 154.0), pituitary deficit (4, 17, 17 %), mean CAB weekly dose (0.7 ± 0.4, 0.6 ± 0.3, 0.7 ± 0.4) and PRL levels before withdrawal (17.1 ± 19.6, 11.4 ± 8.8, 13.8 ± 13.5). Recurrence occurred within 12 months in 34 patients (45.9 %), without significant differences among groups. Neuroradiological evaluation showed a significantly higher presence of macroadenoma in group C (13, 17 and 39 %, respectively). Recurrence rate of hyperprolactinemia did not depend on sex, tumor size or CAB dose but it was significantly correlated with PRL levels at diagnosis and before withdrawal (p = 0.03). Finally, patients with pituitary deficit at diagnosis showed a significantly higher recurrence rate (p = 0.03).

CONCLUSIONS

The study provides additional evidence that prolonging therapy for more than 3 years does not reduce recurrence rate. In particular, recurrence risk was similar in micro- and macroadenomas, and higher in patients with pituitary deficits at diagnosis.

Pituitary tumors in MEN1: do not be misled by borderline elevated prolactin levels

PURPOSE

The objective of this case report is to demonstrate that the simple expedient of measuring periodic prolactin levels in patients with MEN1 who have modest hyperprolactinemia and normal pituitary MRI scans is insufficient to monitor for the development of pituitary adenomas.

METHODS

Review of relevant literature and chart review.

RESULTS

A 25 year old man with known MEN1 manifested by hyperparathyroidism and a gastrin-producing neuroendocrine tumor was found to have a prolactin [PRL] level of 20.0 ng/mL [1.6-16 ng/mL] but a normal pituitary MRI scan. The impression then was that he had prolactinoma too small to be visualized on the MRI. Over the next 3.5 years his PRL levels remained in this mildly elevated range but he then presented with severe headaches and visual field defects. An MRI showed a 3.1 × 1.7 × 1.9 cm pituitary adenoma with compression of the optic chiasm and invasion of the left cavernous sinus. Surgery revealed a gonadotroph adenoma and he subsequently required gamma knife radiotherapy for residual tumor. Postoperative PRL levels were normal.

CONCLUSIONS

Small, intrasellar microadenomas may be associated with elevated PRL levels due to possible direct hormone production [prolactinoma] or possibly to interference with portal vessel blood flow. In monitoring hyperprolactinemic MEN1 patients for the development of pituitary adenomas, measurement of PRL levels is insufficient and periodic MRI scans are necessary at a more frequent interval than every 3-5 years. This may also pertain to patients with "idiopathic" hyperprolactinemia.

Parasellar Extension Grades and Surgical Extent in Endoscopic Endonasal Transsphenoidal Surgery for Pituitary Adenomas : A Single Surgeon's Consecutive Series with the Aspects of Reliability and Clinical Validity

Objective

The inter-rater reliability of the modified Knosp's classification was measured before the analysis. The clinical validity of the parasellar extension grading system was evaluated by investigating the extents of resection and complication rates among the grades in the endoscopic endonasal transsphenoidal surgery (EETS) for pituitary adenomas.

Methods

From November 2008 to August 2015, of the 286 patients who underwent EETS by the senior author, 208 were pituitary adenoma cases (146 non-functioning pituitary adenomas, 10 adrenocorticotropic hormone-secreting adenomas, 31 growth hormone-secreting adenomas, 17 prolactin-secreting adenomas, and 4 thyroid-stimulating hormone-secreting adenomas; 23 microadenomas, 174 macroadenomas, and 11 giant adenomas). Two neurosurgeons and a neuroradiologist independently measured the degree of parasellar extension on the preoperative sellar MRI according to the modified Knosp's classification. Inter-rater reliability was statistically assessed by measuring the intraclass correlation coefficient. The extents of resection were evaluated by comparison of the pre- and post-operative MR images; the neurovascular complications were assessed by reviewing the patients' medical records. The extent of resection was measured in each parasellar extension grade; thereafter, their statistical differences were calculated.

Results

The intraclass correlation coefficient value of reliability across the three raters amounted to 0.862. The gross total removal (GTR) rates achieved in each grade were 70.0, 69.8, 62.9, 21.4, 37.5, and 4.3% in Grades 0, 1, 2, 3A, 3B, and 4, respectively. A significant difference in the extent of resection was observed only between Grades 2 and 3A. In addition, significantly higher complication rates were observed in the groups above Grade 3A.

Conclusion

Although the modified Knosp's classification system appears to be complex, its inter-rater reliability proves to be excellent. Regarding the clinical validity of the parasellar extension grading system, Grades 3A, 3B, and 4 have a negative predictive value for the GTR rate, with higher complication rates.

Long-Term Follow-Up of Primary Medical Versus Surgical Treatment of Prolactinomas in Men: Effects on Hyperprolactinemia, Hypogonadism, and Bone Health

OBJECTIVE

In men with prolactinomas, impaired bone density is the principle consequence of hyperprolactinemia-induced hypogonadism. Although dopamine agonists (DAs) are the first-line approach in prolactinomas, surgery can be considered in selected cases. In this study, we aimed to investigate the long-term control of hyperprolactinemia, hypogonadism, and bone health comparing primary medical and surgical therapy in men who had not had prior DA treatment.

METHODS

This is a retrospective case-note study of 44 consecutive men with prolactinomas and no prior DAs managed in a single tertiary referral center. Clinical, biochemical, and radiologic response to the first-line approach were analyzed in the 2 cohorts.

RESULTS

Mean age at diagnosis was 47 years (range, 22-78 years). The prevalence of hypogonadism was 86%, and 27% of patients had pathologic bone density at baseline. The primary therapeutic strategy was surgery for 34% and DAs for 66% of patients. Median long-term follow-up was 63 months (range, 17-238 months). Long-term control of hyperprolactinemia required DAs in 53% of patients with primary surgical therapy, versus 90% of patients with primary medical therapy (P = 0.02). Hypogonadism was controlled in 73% of patients. The prevalence of patients with pathologic bone density was 37% at last follow-up, with no differences between the 2 therapeutic cohorts (P = 0.48).

CONCLUSIONS

Despite control of hyperprolactinemia and hypogonadism in most patients independent of the primary treatment modality, the prevalence of impaired bone health status remains high, and osteodensitometry should be recommended.

The risks of overlooking the diagnosis of secreting pituitary adenomas

Secreting pituitary adenomas that cause acromegaly and Cushing’s disease, as well as prolactinomas and thyrotroph adenomas, are uncommon, usually benign, slow-growing tumours. The rarity of these conditions means that their diagnosis is not familiar to most non-specialist physicians. Consequently, pituitary adenomas may be overlooked and remain untreated, and affected individuals may develop serious comorbidities that reduce their quality of life and life expectancy. Because many signs and symptoms of pituitary adenomas overlap with those of other, more common disorders, general practitioners and non-endocrinology specialists need to be aware of the “red flags” suggestive of these conditions. A long duration of active disease in patients with secreting pituitary adenomas is associated with an increased risk of comorbidities and reduced quality of life. Appropriate treatment can lead to disease remission, and, although some symptoms may persist in some patients, treatment usually reduces the incidence and severity of comorbidities and improves quality of life. Therefore, correct, early diagnosis and characterization of a pituitary adenoma is crucial for patients, to trigger timely, appropriate treatment and to optimize outcome. This article provides an overview of the epidemiology of hormonal syndromes associated with pituitary adenomas, discusses the difficulties of and considerations for their diagnosis, and reviews the comorbidities that may develop, but can be prevented, by accurate diagnosis and appropriate treatment. We hope this review will help general practitioners and non-endocrinology specialists to suspect secreting pituitary adenomas and refer patients to an endocrinologist for confirmation of the diagnosis and treatment.

Time Course of Resolution of Hyperprolactinemia After Transsphenoidal Surgery Among Patients Presenting with Pituitary Stalk Compression

BACKGROUND

Primary lactotroph disinhibition, or stalk effect, occurs when mechanical compression of the pituitary stalk disrupts the tonic inhibition by dopamine released by the hypothalamus. The resolution of pituitary stalk effect-related hyperprolactinemia postoperatively has not been studied in a large cohort of patients. We performed a retrospective review to investigate the time course of recovery of lactotroph disinhibition after transsphenoidal surgery.

METHODS

Medical records were retrospectively reviewed for all patients undergoing transsphenoidal surgery with the senior author from April 2008 to November 2014.

RESULTS

Of 556 pituitary adenomas, 289 (52.0%) were eliminated: 77 (13.9%) had an immunohistochemically confirmed prolactinoma, 119 (21.4%) patients had previous surgery, 93 (16.7%) had incomplete medical records, leaving 267 patients (48.0%) for final analysis. Of these patients, 72 (27.0%) had increased serum prolactin levels (≥23.3 ng/mL), suggestive of pituitary stalk effect (maximum prolactin level = 148.0 ng/mL). Patients with stalk effect were more likely than those with normal serum prolactin levels to present with menstrual dysfunction (29.7% vs. 19.4%; P < 0.01) and galactorrhea (11.1% vs. 2.1%; P < 0.01). Patients with lactotroph disinhibition were more likely to harbor macroadenomas than were patients who did not show lactotroph disinhibition (81.9% vs. 70.2%; P = 0.06). Among patients with increased preoperative prolactin, 77.8% experienced normalization of serum prolactin postoperatively, galactorrhea improved in 100%, sexual dysfunction resolved in 66.6%, and menstrual dysfunction among premenopausal females normalized in 73.3% at last follow-up (mean, 5.35 years; range, 0.1-10 years).

CONCLUSIONS

Transsphenoidal surgery can provide durable normalization of serum prolactin levels and related symptoms caused by pituitary stalk compression-related lactotroph disinhibition.

Effect of the preoperative use of dopamine agonists in the postoperative course of prolactinomas: a systematic review

OBJECTIVE

Since the 1980s, it has been discussed whether the preoperative treatment of prolactinomas with dopamine agonists (DAs) is beneficial or detrimental regarding postoperative residue or recurrence. Many neurosurgeons have emphasized the difficulties caused by fibrosis during the ablation of such prolactinomas.

METHODS

From February to December 2012, the authors searched electronic databases and book chapters published from 1991 to 2012; a total of 3,771 articles and 37 book chapters were searched. Ten articles that explicitly addressed this issue were identified.

RESULTS

Five articles reported that preoperative treatment did not affect postoperative status. One article described a positive influence of preoperative treatment with DAs (P < .01), and 3 articles found a negative influence (P = .040, P = .02, no significance value reported). One article described histopathological evidence of tumor fibrosis that was found intraoperatively after preoperative DA treatment.

CONCLUSIONS

This systematic review did not identify any strong evidence that preoperative treatment of prolactinomas with DAs is harmful or beneficial. Therefore, further studies are needed.

Obesity and hypercholesterolemia in patients with prolactinomas: Could DHEA-S and growth hormone be the missing link?

PURPOSE

Increasing evidence exists that hyperprolactinemia alters metabolic profile. The mechanism of this effect is unknown. We aimed to investigate the differences between the metabolic profile of patients with prolactinomas and nonfunctional pituitary adenomas and to evaluate the impact of other pituitary hormones on their metabolic profile.

METHODS

Our retrospective study included 86 consecutive patients with prolactinomas and nonfunctional adenomas (29 prolactinomas and 57 adenomas). Body mass index (BMI), blood pressure, serum prolactin, growth hormone (GH), insulin-like growth factor I (IGF-I), adrenocorticotropic hormone (ACTH), cortisol, urinary free cortisol, triiodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), dehydroepiandrosterone-sulfate (DHEA-S), testosterone in men, triglycerides, total cholesterol, HDL (high-density lipoprotein) cholesterol, LDL (Low-density lipoprotein) cholesterol, alanine-transaminase, aspartate-transaminase, fasting glucose, and C-reactive protein (CRP) were obtained for all patients. Regression analyses were performed on log-transformed data.

RESULTS

After adjustment for age, gender, and tumor size, prolactinomas were associated with higher BMI (OR 5.61, 95%CI 1.70-9.51, p = 0.005), LDL cholesterol (OR 3.60, 95%CI 1.35-5.93, p = 0.015), DHEA-S (OR 1.97, 95%CI 1.23-3.72, p = 0.026), and lower GH levels (OR 0.43, 95%CI 0.03-0.84, p = 0.037). In a linear multivariate regression, the association between DHEA-S, GH, and prolactin remained significant even after adjustment for BMI. GH and IGF-I were associated with BMI and LDL cholesterol, but the association diminished after adjustment for serum prolactin.

CONCLUSIONS

Prevalence of obesity is four times higher in patients with prolactinomas than in patients with nonfunctional adenomas. Higher DHEA-S and lower GH levels in patients with prolactinomas may have an important role in prolactin-induced metabolic effects. Further studies are needed.

The higher incidence of autoimmune thyroid disease in prolactinomas than in somatotrophinomas

OBJECTIVE

Many studies have shown that prolactin (PRL) plays an important role in autoimmune diseases. The aim of this study was to compare the current frequency of autoimmune thyroid disease (ATD) in prolactinomas with another type of functional pituitary adenoma (FPA), somatotrophinoma. Another aim of the study was to evaluate possible factors related to thyroid autoimmunity and the process of ATD in FPAs.

METHODS

We retrospectively evaluated the presence of thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb) and thyroid morphologic findings in our patients with FPA (78 with acromegaly and 83 with prolactinoma). The relationship of autoantibody positivity with baseline PRL levels, activity of acromegaly, and treatment of dopamine agonists (DA) and hypogonadism was also assessed. Patients with ATD and hypothyroidism due to autoimmune thyroiditis were also evaluated.

RESULTS

ATD (Hashimoto's thyroiditis) was detected more frequently in patients with prolactinoma than in patients with acromegaly (33% and 17%, respectively; p=0.01). Thyroid autoantibody positivity was found more frequently in females in the whole group (p=0.02) and in the acromegaly group (p=0.008). There was no difference according to sex among the patients with prolactinoma (p=0.800). ATD was found not to be related with baseline PRL levels, treatment of DA, and presence of hypogonadism (p=0.232, p=0.435, p=0.464, respectively) in the prolactinoma group, and activity of acromegaly, presence of hypogonadism in the acromegaly group (p=0.753, p=0.654, respectively). Autoimmune hypothyroidism was more frequent in the prolactinoma group than in the acromegaly group among patients with thyroid autoantibody positivity (p=0.004).

CONCLUSION

Thyroid autoantibodies should be evaluated both at the time of diagnosis and during the course of treatment in patients with prolactinoma, and thyroid function tests should be closely monitored in patients with autoantibody positivity.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS, AMERICAN COLLEGE OF ENDOCRINOLOGY DISEASE STATE CLINICAL REVIEW: CLINICAL RELEVANCE OF MACROPROLACTIN IN THE ABSENCE OR PRESENCE OF TRUE HYPERPROLACTINEMIA

OBJECTIVE

To review the current literature regarding the prevalence of macroprolactin (macroPRL) in hyperprolactinemic patients and determine recommendations for testing.

METHODS

An electronic United States National Library of Medicine PubMed search (through October, 2014) was conducted for search term "macroprolactin." Only English-language articles were considered.

RESULTS

MacroPRL is an under-recognized cause of elevated prolactin (PRL) and is present in approximately 4% to 40% of hyperprolactinemic patients depending on the referral population. Clinical findings which could be due to hyperprolactinemia are the impetus for testing for PRL. Because of this there is significant overlap in the clinical presentation of patients with true hyperprolactinemia and those with macroPRL, differentiation cannot always be made on the basis of symptoms. A lack of recognition of the presence of macroPRL can lead to unnecessary laboratory investigations, imaging, and pharmacologic or surgical treatment.

CONCLUSION

Until there is a commercially available PRL assay that is not subject to interference by macroPRL, clinicians should consider the possibility of macroPRL, especially if the clinical presentation, imaging findings, and/or response to therapy reveal inconsistencies.