Giant prolactinomas: the therapeutic approach

The Effect of Preoperative Cabergoline on Prolactinoma Fibrosis: A Case Series

Introduction  Prolactinomas are a common intracranial neoplasm and constitute most pituitary tumors. Although patients can present with variable hormone dysregulation and symptom severity, the use of dopamine agonists remains a first-line treatment. While bromocriptine has been found to increase tumor fibrosis, the effect of cabergoline on collagen deposition has been disputed. The aim of this article is to understand the influence of cabergoline on tumor fibrosis prior to resection. Case Presentations  Four male patients who underwent prolactinoma resection were included in this report. The average age was 39.8 years (range: 26-52 years). Pre-treatment prolactin levels ranged from 957.8 to 16,487.4 ng/mL. Three patients received cabergoline for at least 1 month prior to surgery (treatment range: 1-6 months). One patient had surgery without prior cabergoline use. Pathology reports confirmed each tumor to be of lactotroph origin. For each sample, Masson's trichrome staining was performed and the percentage of sample fibrosis was quantified using an artificial intelligence imaging software. Among those who received preoperative cabergoline, the extent of tumor fibrosis was in the range of 50 to 70%. In contrast, specimen fibrosis was approximately 15% without cabergoline use. Conclusion  This report demonstrates that a short duration of preoperative cabergoline can cause significant prolactinoma fibrosis. Understanding the effect of cabergoline on tumor consistency prior to surgery is essential as increased fibrosis can lead to more difficult tumor removal, reduce the extent of resection, and increase surgical complications. Considering these effects, further studies regarding the use of surgery prior to cabergoline for prolactinoma management are warranted.

Prolactin-secreting pituitary adenomas: male-specific differences in pathogenesis, clinical presentation and treatment

Prolactinomas (PRLomas) constitute approximately half of all pituitary adenomas and approximately one-fifth of them are diagnosed in males. The clinical presentation of PRLomas results from direct prolactin (PRL) action, duration and severity of hyperprolactinemia, and tumor mass effect. Male PRLomas, compared to females, tend to be larger and more invasive, are associated with higher PRL concentration at diagnosis, present higher proliferative potential, are more frequently resistant to standard pharmacotherapy, and thus may require multimodal approach, including surgical resection, radiotherapy, and alternative medical agents. Therefore, the management of PRLomas in men is challenging in many cases. Additionally, hyperprolactinemia is associated with a significant negative impact on men's health, including sexual function and fertility potential, bone health, cardiovascular and metabolic complications, leading to decreased quality of life. In this review, we highlight the differences in pathogenesis, clinical presentation and treatment of PRLomas concerning the male sex.

Giant prolactinoma in Asian-Indians: A single-center experience from Western India

PURPOSE

Giant prolactinomas (GP) are rare tumors accounting for 4.3% of prolactinomas, with paucity of literature from India. We aim to describe clinical, biochemical, radiological, and treatment outcomes in a large series of Asian-Indian patients with GP.

METHODS

A single-center retrospective analysis of GPs (n=84), age-based (adults: 66 versus pediatric: 18) and gender-based (males: 64 versus females: 20) comparison was done.

RESULTS

The mean age at presentation was 34.1±13years, and 64 (76.2%) were males. Males were younger at presentation (32.1±12.2 versus 40.1±13.8years, P: 0.01). The majority presented with mass-effect-related manifestations (visual disturbances: 91.6%, headache: 84.5%) and/or hypogonadism (98.7%). At baseline, largest tumor dimension was 5.3±1.0cm, and serum prolactin was 8343 (3865.5-12,306) ng/mL; most (94.6%) had gonadal axis involvement. Dopamine-agonist (DA) as first-line therapy (45/67, 67.2%) achieved normoprolactinemia (maximum cabergoline dose: 2.0±1.2mg/week) in 36/45 (80%) and tumor response (≥50% reduction) in 36/37 (97.3%) patients at the last follow-up (median duration: 33 [14.5-53.5]months). Notably, gonadal axis recovery was poor (6/30, 20%) despite normoprolactinemia post-DA monotherapy. At latest follow-up, secondary hypothyroidism (32.5% versus 82.6%, P: 0.001) and central hypocortisolism (5.6% versus 42.9%, P: 0.007) were less frequent in DA monotherapy (n=43) than in multimodal therapy group (n=23). The proportion of males (94.4% versus 71.2%, P: 0.04) was higher in the pediatric age group, with DA-induced (first-line) normoprolactinemia observed in 66.7% of them.

CONCLUSION

GP has male predominance, DA as first-line therapy normalized prolactin in four-fifths of patients with better preservation of HPT and HPA axes in patients with DA monotherapy.

Long-term Discontinuation of Dopamine Agonist Treatment in Patients with Prolactinomas Revisited

The most common type of functioning pituitary adenomas is prolactinomas; unlike other types, they are treated medically with dopamine agonists (DA). This treatment aims to normalize PRL levels and decrease tumor size by 50% or more. These objectives are typically achieved by 90% of patients with microprolactinoma, two-thirds of those with macroprolactinomas, and about half of those with giant prolactinomas. Life-long pharmacological treatment implies costs, discomfort, and the possibility of side effects, therefore, it has been suggested that DA discontinuation could be attempted in some patients. Long-term remission seems more likely in who, after 2 years of therapy achieve clinical, biochemical, and imaging remission criteria: no evidence of hypogonadism, a normal PRL level (preferably <5 ng/mL), and a >50% of tumor size reduction. Long-term remission seems to be more likely if the patient has been treated with cabergoline (CBG) for a minimum of 2 years, the PRL levels have normalized, tumor size has decreased by at least 50%, and the DA dose can gradually be tapered down to 0.25-0.5 mg per week. After treatment withdrawal, about 65% of patients experience a recurrence of hyperprolactinemia within the first 12 months of DA discontinuation. Although in most patients in whom DA discontinuation has been attempted, the hyperprolactinemia will recur, not all of them will require re-initiation of treatment. A good clinical judgement is crucial to identify those patients who need life-long treatment.

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.

Long-term Follow-up of 84 Patients With Giant Prolactinomas-A Swedish Nationwide Study

PURPOSE

To describe the clinical presentation and treatment outcomes in a nationwide cohort of patients with giant prolactinomas.

METHODS

Register-based study of patients with giant prolactinomas [serum prolactin (PRL) > 1000 µg/L, tumor diameter ≥40 mm] identified in the Swedish Pituitary Register 1991-2018.

RESULTS

Eighty-four patients [mean age 47 (SD ±16) years, 89% men] were included in the study. At diagnosis, the median PRL was 6305 µg/L (range 1450-253 000), the median tumor diameter was 47 mm (range 40-85), 84% of the patients had hypogonadotropic hypogonadism, and 71% visual field defects. All patients were treated with a dopamine agonist (DA) at some point. Twenty-three (27%) received 1 or more additional therapies, including surgery (n = 19), radiotherapy (n = 6), other medical treatments (n = 4), and chemotherapy (n = 2). Ki-67 was ≥10% in 4/14 tumors. At the last follow-up [median 9 years (interquartile range (IQR) 4-15)], the median PRL was 12 µg/L (IQR 4-126), and the median tumor diameter was 22 mm (IQR 3-40). Normalized PRL was achieved in 55%, significant tumor reduction in 69%, and combined response (normalized PRL and significant tumor reduction) in 43%. In the primary DA-treated patients (n = 79), the reduction in PRL or tumor size after the first year predicted the combined response at the last follow-up (P < .001 and P = .012, respectively).

CONCLUSION

DAs effectively reduced PRL and tumor size, but approximately 1 patient out of 4 needed multimodal treatment. Our results suggest that the response to DA after 1 year is useful for identifying patients who need more careful monitoring and, in some cases, additional treatment.

The Value of ER∝ in the Prognosis of GH- and PRL-Secreting PitNETs: Clinicopathological Correlations

Pituitary neuroendocrine tumors (PitNETs) are divided into multiple histological subtypes, which determine their clinical and biological variable behavior. Despite their benign evolution, in some cases, prolactin (PRL) and growth hormone (GH)-secreting PitNETs may have aggressive behavior. In this study, we investigated the potential predictive role of ER∝, alongside the clinicopathological classification of PitNETs (tumor diameter, tumor type, and tumor grade). A retrospective study was conducted with 32 consecutive cases of PRL- and mixed GH- and PRL-secreting PitNETs (5 patients with prolactinomas and 27 with acromegaly, among them, 7 patients with GH- and PRL- co-secretion) who underwent transsphenoidal intervention. Tumor specimens were histologically and immunohistochemical examined: anterior pituitary hormones, ki-67 labeling index, CAM 5.2, and ER∝; ER∝ expression was correlated with basal PRL levels at diagnosis (rho = 0.60, p < 0.01) and postoperative PRL levels (rho = 0.58, p < 0.001). In our study, the ER∝ intensity score was lower in female patients. Postoperative maximal tumor diameter correlated with Knosp grade (p = 0.02); CAM 5.2 pattern (densely/sparsely granulated/mixed densely and sparsely granulated) was correlated with postoperative PRL level (p = 0.002), and with ki-67 (p < 0.001). The IGF1 level at diagnosis was correlated with the postoperative GH nadir value in the oral glucose tolerance test (OGTT) (rho = 0.52, p < 0.05). Also, basal PRL level at diagnosis was correlated with postoperative tumor diameter (p = 0.63, p < 0.001). At univariate logistic regression, GH nadir in OGTT test at diagnostic, IGF1, gender, and invasion were independent predictors of remission for mixed GH- and PRL-secreting Pit-NETs; ER∝ can be used as a prognostic marker and loss of ER∝ expression should be considered a sign of lower differentiation and a likely indicator of poor prognosis. A sex-related difference can be considered in the evolution and prognosis of these tumors, but further studies are needed to confirm this hypothesis.

De Novo Psychiatric Disorders in a Woman With Giant Prolactinoma Treated With Cabergoline

Dopamine agonists are the first-line treatment of prolactinomas. The risk of developing de novo psychiatric symptoms during dopamine agonist therapy is low. Herein, we report the case of a 42-year-old woman with a giant prolactinoma who developed a psychiatric disorder after 1 day of cabergoline therapy initiation. She presented with amenorrhea, galactorrhea, headaches, and disturbed vision. Biological investigations revealed hyperprolactinemia (2975 ng/ml) with gonadotropin deficiency. Pituitary MRI showed a giant pituitary adenoma. The patient was treated with cabergoline at the dose of 1 mg twice weekly. One day after the treatment initiation, she developed acute delirium with temporospatial disorientation and compulsive medication use. These symptoms disappeared 1 week after the reduction of the dose of cabergoline. Patients with hyperprolactinemia receiving an initial high dose of cabergoline may develop changes in mood and behavior regardless of prior psychiatric history.

A giant invasive macroprolactinoma with recurrent nasal bleeding as the first clinical presentation: case report and review of literature

BACKGROUND

Giant prolactinoma (> 4 cm in dimension) is a rare disorder. Invasive macroprolactinoma has the potential to cause base of skull erosion and extend into the nasal cavity or even the sphenoid sinus. Nasal bleeding caused by intranasal tumor extension is a rare complication associated with invasive giant prolactinoma. We report a case of giant invasive macroprolactinoma with repeated nasal bleeding as the initial symptom.

CASE PRESENTATION

A 24-year-old man with an invasive giant prolactinoma in the nasal cavity and sellar region who presented with nasal bleeding as the initial symptom, misdiagnosed as olfactory neuroblastoma. However, markedly elevated serum prolactin levels (4700 ng/mL), and a 7.8-cm invasive sellar mass confirmed the diagnosis of invasive giant prolactinoma. He was treated with oral bromocriptine. Serum prolactin was reduced to near normal after 6 months of treatment. Follow-up magnetic resonance imaging showed that the sellar lesion had disappeared completely and the skull base lesions were reduced.

CONCLUSION

This case is notable in demonstrating the aggressive nature of untreated invasive giant prolactinomas which can cause a diagnostic difficulty with potential serious consequences. Early detection of hormonal levels can avoid unnecessary nasal biopsy. Early identification of pituitary adenoma with nasal bleeding as the first symptom is particularly important.

Surgical Management of Giant Prolactinomas: A Descriptive Study

Introduction

Giant prolactinoma (GP) is a rare pituitary lactotropic cell tumor larger than 4 cm in its widest dimension, and is less likely than a smaller prolactinoma to achieve prolactin normalization on dopamine agonist (DA) monotherapy. There is a paucity of data on the circumstances and outcomes of second-line management of GP with surgery. Herein, our institution's experience with the surgical management of GPs is described.

Methods

A single-center retrospective analysis was conducted of patients who underwent surgery for giant prolactinoma from 2003 to 2018. A chart review was conducted for demographic data, clinical features, laboratory and radiographic findings, operative and pathology reports, perioperative management, and clinical outcomes in follow-up. Descriptive statistics were used.

Results

Of 79 prolactinoma cases, 8 patients had GP with a median age of 38 years (range 20-53), 75% (6/8) were male, with a median largest tumor dimension of 6 cm (range 4.6-7.7), and a median prolactin level of 2,500 μg/L (range 100->13,000). Six patients had transsphenoidal surgery for dopamine agonist (DA) resistance or intolerance. Two patients had a craniotomy for a missed diagnosis; one was due to the hook effect. No tumor resections were complete by either surgical approach; all had persistent hyperprolactinemia requiring postoperative DA therapy, and two patients had an additional craniotomy procedure for further tumor debulking. There was no recovery of pituitary axes and postoperative deficits were common. Remission as defined by prolactin normalization occurred in 63% (5/8) at a median time of 36 months (range 14-63 months) on DA therapy after surgery with a follow-up of 3-13 years.

Conclusions

GPs infrequently require surgical resection, which is generally incomplete and requires adjuvant therapy. Given the rarity of surgery for GPs, multi-institutional or registry studies would yield clearer guidance on optimal management.

A case of acute hydrocephalus due to a giant prolactinoma rescued by transventricular neuroendoscopic tumorectomy

Background

A giant prolactinoma extending to the suprasellar area and causing hydrocephalus may be life-threatening and should be treated promptly. A case of a giant prolactinoma with acute hydrocephalus that underwent transventricular neuroendoscopic tumor resection followed by cabergoline administration is presented.

Case Description

A 21-year-old man had a headache lasting for about a month. He gradually developed nausea and disturbance of consciousness. Magnetic resonance imaging showed a contrast-enhanced lesion that extended from the intrasellar space to the suprasellar space and into the third ventricle. The tumor obstructed the foramen of Monro and caused hydrocephalus. A blood test showed marked elevation of prolactin (16,790 ng/mL). The tumor was diagnosed as a prolactinoma. The tumor in the third ventricle had formed a cyst, and the cyst wall blocked the right foramen of Monro. The cystic component of the tumor was resected using an Olympus VEF-V flexible neuroendoscope. The histological diagnosis was pituitary adenoma. The hydrocephalus improved rapidly and his consciousness became clear. After the operation, he was started on cabergoline. The tumor size subsequently decreased.

Conclusion

Prompt partial resection of the giant prolactinoma by transventricular neuroendoscopy resulted in early improvement of hydrocephalus with less invasiveness, allowing subsequent treatment with cabergoline.

Giant prolactinoma in children and adolescents: a single-center experience and systematic review

PURPOSE

Giant prolactinoma (GP) in childhood and adolescence is a rare entity with scarce literature. We aimed to describe clinical features, biochemistry, radiology, genetics, management, and outcome in pediatric (≤ 20 years) GP.

METHODS

Retrospective record review of 18 pediatric GP patients from our center and systematic review including these and 77 from the literature (total cohort: 95).

RESULTS

GP constituted 20% of our pediatric prolactinoma cohort. In the total cohort (age: 15.4 ± 3.5 years), the majority (77, 82.8%) were males. Mass effect symptoms (88.6%), and pubertal delay/arrest in males (82.1%) were frequent. Median basal prolactin was 8649 (3246-17,532) ng/ml and the maximum tumor dimension was 5.5 ± 1.5 cm. MEN1 and AIP mutations were noted in 7 (21.9%) and 6 (18.8%) patients, respectively. Males with central hypogonadism had baseline bi-testicular volume of 20.2 ± 8.4 cc, lower LH than FSH (-2.04 ± 0.9 vs. -0.7 ± 1.6 SDS, p = 0.0075), and mostly, normal inhibin B. Majority (49/76, 64.5%) received dopamine agonist (DA) as first-line treatment with additional therapy in 35% (17/49). DA monotherapy arm had less frequent central hypothyroidism (42.9% vs 87.1%, p = 0.002) and central adrenal insufficiency (7.1% vs 66.7%, p = 0.0003) than multimodal therapy. A smaller tumor dimension (4.7 vs. 5.7 cm, p = 0.04) was associated with normoprolactinemia on DA monotherapy and AIP mutations (33.3% vs. nil, p = 0.02) with multimodal therapy.

CONCLUSION

GP is characterized by male predominance with frequent delay/arrest of puberty (82%), but relative sparing of the FSH-inhibin B axis in boys. DA monotherapy may be preferred as the first-line therapy in pediatric GP.

Giant Non-Functioning Pituitary Adenomas: Treatment Considerations

Giant pituitary adenomas are a subgroup of pituitary adenomas defined by a diameter greater than 4 cm, and they account for 5-14% of adenomas in surgical series. Because of their growth patterns and locations, often involving critical neurovascular structures, they represent a true surgical challenge, and gross total resection is difficult to achieve. There is no consensus on the optimal surgical strategy for giant pituitary adenomas, and, often, integrated multi-staged treatment strategies have been considered. Transcranial or transsphenoidal approaches, alone or combined, according to tumor and patient features are the two main routes. Each of these strategies has pros and cons. The conventional transcranial approach has for a long time been considered the first choice for the removal of giant pituitary adenomas. Currently, with endoscopic techniques, it is also possible to remove lesions that involve the intradural compartment and the adjacent neurovascular structures with the use of extended approaches. Our policy for the management of these lesions is to adopt the endoscopic endonasal approach as the first choice unless the tumor presents significant intracranial extension that results in it being outside the visibility and maneuverability of the endoscopic endonasal route. In these latter cases, we agree that the transcranial approach is more appropriate. However, accurate preoperative evaluation and refined treatment plans for each patient are mandatory to define a proper strategy in order to achieve the most effective long-term result.

Foster Kennedy syndrome secondary to a giant prolactinoma with a remarkable response to cabergoline

Summary

Pituitary adenomas are intracranial neoplasms, usually demonstrating a benign phenotype. We present the case of 21-year-old male with an 18-month history of reduced visual function (acuity and field) in the left eye. Based on neuroimaging and endocrine profile, a giant prolactinoma causing hypogonadotropic hypogonadism was diagnosed and cabergoline was commenced. After a month of treatment, the tumour size reduced, and visual function improved to normal; however, he developed Foster Kennedy syndrome with a swollen right optic disc. After almost 1 year of follow-up, he regained full visual functioning. Two years since his diagnosis, his prolactin remains normal with no adverse effects or further visual complications.

Learning points

Foster Kennedy syndrome is a rare entity but can be a feature of pituitary adenomas. Visual deterioration secondary to a compressive optic neuropathy can be reversible, provided that diagnosis and treatment are prompt. This case highlights the importance of frequent monitoring of visual function during follow-up of these lesions, particularly when there are deficits at diagnosis.

Resistant prolactinomas: a case series of 26 patients

PURPOSE

Prolactin (PRL)-secreting tumors are the most common functional pituitary adenomas. They usually respond to dopamine agonist (DA) treatment, with PRL normalization and adenoma shrinkage. Our aim was to characterize patients with prolactinoma resistant to DA treatment.

METHODS

This retrospective case series included patients diagnosed with DA-resistant prolactinomas between 1993-2017 in three medical centers. Resistance was defined as PRL levels above three times the upper limit of normal (ULN) despite a weekly dose of ≥2 mg cabergoline (CAB). Clinical and biochemical information, and response to treatment, were retrieved from medical records.

RESULTS

Twenty-six patients were identified; 20 males. Of 25 macroadenomas, three were giant tumors (>40 mm) and 15 (57.7%) were invasive. The mean age at diagnosis was 31.8 ± 14.9 years (range: 13-62). The median maximal CAB dose was 3.5 mg/week (IQR, 2.5-5). Half the patients received only CAB in escalating doses, nine received CAB and underwent transsphenoidal surgery, and four underwent surgery and radiotherapy in addition to CAB treatment. PRL levels at baseline between patients treated only with CAB and those operated were (91.6 [51.1-296.7] vs. 73.1 [22.6-170.9] XULN p = 0.355), and under maximal CAB dose PRL levels between patients treated only with CAB and those operated were similar (5.77 [1.27-11.27] vs 5.27 (2.9-26) XULN p = 0.317). At the last visit patients who received combined therapy achieved lower PRL levels than those treated with DA only (5.22 [1.7-21.6] vs 1.1 [0.44-3.99] XULN p = 0.017) PRL normalization was attained in seven patients and levels below 3 × ULN in fourteen patients; the overall response was 56%.

CONCLUSIONS

Resistant prolactinomas usually require a multi-modal treatment strategy. We were able to control 14/25 (56%) of resistant tumors.

Dopamine agonist for the rapid improvement of visual field defects in giant and macro-prolactinomas

PURPOSE

To evaluate effect of first-line dopamine agonist (DA) therapy as an alternative to surgery for visual field defect (VFD) recovery in giant and macro-prolactinoma.

METHODS

In this retrospective study, 125 patients with giant and macro-prolactinoma, except those with a history of previous surgery or radiotherapy, were evaluated. Those who underwent visual field examinations using the Humphrey Visual Field analyser upon initial assessment and after treatment were included for analysis. Twelve patients with VFD were included. The effects of DA therapy on both VFD and tumor size were evaluated within the first three months.

RESULTS

There were twelve patients analysed: three females and nine males, five giant and seven macroprolactinomas; eight patients received cabergoline (CAB) and four patients received bromocriptine (BRC). The mean adenoma diameter was 35±13mm (range 15-60), and the mean PRL level was 3,523ng/dL (range 312-11,703). Eight patients (67%) complained of blurred vision, while four patients (33%) reported no visual symptoms. After a median duration of three weeks, the VFD completely resolved in ten patients (83%) but only partially improved in two (17%). The mean initial doses of CAB and BRC that provided VFD improvement were 0.5±0.2mg/week and 6.3±1.4mg/day, respectively. After a mean duration of 2.2±0.9months, the mean decrease in adenoma size was 43.6±24.5% (range 10-95%).

CONCLUSION

The use of DA as a first-line treatment for at least one month before deciding on surgery is recommended in giant and macro-prolactinomas with VFD. Surgery should be considered only in cases with DA resistance or persistent visual impairment despite medical therapy.

Outcome of Endoscopic Transsphenoidal Surgery for Recurrent or Residual Pituitary Adenomas and Comparison to Non-Recurrent or Residual Cohort by Propensity Score Analysis

OBJECTIVE

To evaluate the long-term outcomes and safety of endoscopic transsphenoidal surgery (ETS) in recurrent and residual pituitary adenomas (rrPAs), as well as the predictors of gross total resection (GTR) and intraoperative CSF leakage. Furthermore, to compare outcomes and complications with non-rrPAs cohort.

METHODS

Clinical and radiological characteristics of patients with rrPAs who underwent ETS were collected between 2017 and 2020. Data of patients with non-rrPAs were collected from 2019 to 2020. Logistic regression analyses were performed to investigate the factors influencing gross total resection (GTR) and intraoperative CSF leakage. Between-group comparisons of outcomes and complications were performed through propensity score analysis.

RESULTS

We enrolled 73 patients with rrPAs. GTR was achieved in 41 (56.1%) cases; further, GTR or near-total resection was achieved in 93.2% of patients. The mean tumor volumes for GTR and non-GTR cases were 6.2 ±7.2 cm³ and 11.1 ±9.1 cm³, respectively. Multivariate regression analysis of the GTR rate in patients with rrPAs revealed that Knosp grade was an independent factor (odds ratio [OR] = 0.324; p=0.005). Moreover, previous transcranial surgery and non-functional pituitary adenomas were risk factors for intraoperative CSF leakage in patients with rrPAs (OR=6.450, p=0.019 and OR=7.472, p=0.012, respectively). After propensity score matching, There was no significant difference in the GTR rate between patients with rrPAs and patients with non-rrPAs. Contrastingly, patients with rrPAs had a higher rate of intraoperative CSF leakage and longer postoperative hospital stay than patients with non-rrPAs. During the follow-up, vision improved in 9 (22.0%) and 24 (62.5%) patients with rrPAs and non-rrPAs, respectively. Although there was a trend that reoperation of rrPAs involved a lower hypopituitarism recovery rate and biochemical remission rate, as well as a higher hypopituitarism rate, there was no statistically significant between-group difference.

CONCLUSIONS

Knosp grade was an independent factor for GTR in endoscopic transsphenoidal surgery in patients with rrPAs. Previous transcranial surgery and non-functional PAs were risk factors for intraoperative CSF leakage. Although associated with longer hospital stay, rrPAs did not associate with lower GTR rate or more frequent postoperative complications than non-rrPAs cohort.

Optimal testosterone level to improve symptoms of hypogonadism without causing dopa-testotoxicosis in male macroprolactinoma

BACKGROUND

Male prolactinoma treatment by dopamine agonists (DA) restores sexual function. However, excessive DA dose can lead to impulse control disorder.

OBJECTIVES

The aim of this retrospective study was to determine the level of testosterone that eliminates symptoms and provides fertility in male macroprolactinoma, without causing these adverse effects.

MATERIALS AND METHODS

Twenty-seven male patients with macroprolactinoma were included. There were 16 macro (≥1-2.8 cm), 7 large macro (≥2.9-3.9 cm) and 4 giant (≥4 cm) adenomas. Prolactin (PRL) and testosterone (T) levels were evaluated. A timeline was created to analyze improvement in symptoms of hypogonadism and infertility. Testosterone levels were compared with age-matched controls.

RESULTS

Mean PRL, basal tumor diameter and shrinkage were 2,846±3,415 ng/mL, 27.2±10.2 mm and 63.4%, respectively. Basal T levels were 1.6±1.0 ng/mL for patients and 4.4±1.5 ng/mL for controls (p<0.001). Mean T level in the asymptomatic period was significantly lower than in controls (3.2±0.4 ng/mL vs. 4.4±1.5 ng/mL, respectively; p=0.002), while mean PRL was 27.2 ng/ml. Fertility was achieved in 6 of the patients seeking fertility, and there was no difference in T level between these patients and controls (3.7±0.8 ng/mL and 4.4±1.5 ng/mL, respectively; p=0.14); when fertility was achieved, mean PRL was 26.9±23 ng/mL.

CONCLUSION

Patients should be carefully questioned regarding complaints at each consultation, and DA dose should not be increased unnecessarily, to avoid possible serious adverse effects.

Efficacy and Cerebrospinal Fluid Rhinorrhea after Cabergoline Treatment in Patients with Bioactive Macroprolactinoma

Predicting dopamine agonist resistance in patients with macroprolactinoma is essential for clinicians to prevent treatment failure and subsequent complications such as medication-induced cerebrospinal fluid (CSF) rhinorrhea. We evaluated the features of patients with cabergoline resistance and CSF rhinorrhea in patients with prolactinomas with prolactin levels ≥1000 ng/mL. A total of 140 patients who were newly diagnosed with prolactinoma secreting only prolactin ≥1000 ng/mL and treated with cabergoline for the first time were included in this study. Based on the hormonal and radiologic response of the prolactinoma, the patients were divided into responders and non-responders. Non-responders (36/140, 25.8%) included a higher number of patients receiving hormone replacement than responders (responders, n (%) = 12(11.5) vs. non-responders = 13(36.1), p = 0.001). In propensity score matching analysis, patients who developed CSF rhinorrhea presented more frequent hormone deficiency than responders regardless of initial cabergoline dose. Hormone deficiency was associated with a greater odds ratio for the risk of non-responders (adjusted odds ratio = 5.13, 95% CI 1.96-13.46, p = 0.001). Cabergoline was effective in bioactive macroprolactinoma. Furthermore, initial cabergoline dose was not significantly associated with long-term responsiveness and development of CSF rhinorrhea but the hypopituitarism was independently associated with an increased risk of cabergoline resistance and CSF rhinorrhea.

Prolactinomas

Hyperprolactinemia, defined by a level of serum prolactin above the standard upper limit of normal range, is a common finding in clinical practice and prolactinomas are the main pathological cause. Prolactinomas lead to signs and symptoms of hormone oversecretion, such as galactorrhea and hypogonadism, as well as symptoms of mass effect, including visual impairment, headaches and intracranial hypertension. Diagnosis involves prolactin measurement and sellar imaging, but several pitfalls are involved in this evaluation, which may difficult the proper management. Treatment is medical in the majority of cases, consisting of dopamine agonists, which present high response rates, with a very favorable safety profile. Major adverse effects that should be monitored consist of cardiac valvulopathy and impulse control disorders. Other treatment options include surgery and radiotherapy. Temozolomide may be used for aggressive or malignant carcinomas. Finally, pregnancy outcomes are similar to general population even when dopamine agonist treatment is maintained.

Long-term response to cabergoline and multi-modal treatment in men with macroprolactinoma: Does size really matter?

OBJECTIVE

To study the outcome of men with macroprolactinoma following cabergoline treatment based on tumour size.

DESIGN

Retrospective cohort study.

METHODS

The study included 94 men, divided into three groups according to adenoma diameter: 10-19 mm (Group A, n = 36); 20-39 mm (Group B, n = 41); or ≥40 mm (Group C, giant prolactinomas, n = 17). Patients were followed for a mean of 7.5 years with sellar magnetic resonance imaging, visual fields and hormone measurements.

RESULTS

Mean baseline prolactin was 767, 2090 and 24,806 ng/ml in Groups A, B and C, respectively (p < .01). Prolactin suppression below three times the upper limit of normal (ULN) was achieved in 34 (94%; mean weekly cabergoline dose of 1.2 mg), 37 (90%; cabergoline dose, 2.1 mg) and 15 (88%; cabergoline dose, 2.8 mg) men (p = .31) in each group. After excluding patients who underwent surgery and radiotherapy, cabergoline suppressed prolactin below three times ULN in 32/35 (91%), 29/37 (78%) and 11/14 (79%) men in Groups A, B and C, respectively (p = .27). Visual deficits were observed in 5 (14%), 12 (29%) and 10 (59%) patients (p < .01); improvement was achieved in 5/5 (100%), 11/12 (92%) and 10/10 (100%) of men in Groups A, B and C. Low baseline testosterone was measured in 26 (72%), 39 (95%) and 17 (100%) patients in the three groups (p < .01). Following multi-modal treatment, hypogonadism persisted in 3 (8%), 5 (12%) and 2 (12%) men, respectively (p = .85).

CONCLUSION

Macroprolactinomas in men were controlled with cabergoline in 84% of cases, independent of tumour size. Pituitary surgery and adjuvant radiotherapy further improved long-term response to 91%.

Comparison of the effects of medical and surgical treatments in giant prolactinoma: a single-center experience

PURPOSE

Giant prolactinomas, which have extremely large sizes and high prolactin (PRL) values, are rarely seen. Although medical therapy is effective, surgical treatment is more frequently applied due to slightly lower response rates and compression symptoms. This study aimed to compare the medical and surgical treatment results in giant prolactinomas.

METHODS

Thirty-nine patients who were followed up in our center for giant prolactinoma were included in the study, and the response rates of the patients were evaluated after the medical and surgical treatments. The treatment responses were compared in terms of tumor volume, PRL level, visual field, and pituitary function.

RESULTS

The outcomes of the 66 treatment periods (medical n = 42; surgical n = 24) in 39 patients (mean age, 47.2 years; men, 89.7%) were evaluated. The most common presentations were hypogonadism and visual defects. The mean longest tumor diameter at diagnosis was 52.2 ± 11.8 mm, and the median PRL levels were 5000 ng/mL. PRL level normalization was achieved in 69% with medical therapy, and a curative response was obtained in only two patients with surgery. Tumor volume reduction was 67% (no cure) in the medical and 75% (13% cure) in the surgical groups (p = 0.39). Improvement of visual field was 70.8% in the medical and 84.2% in the surgical group (p = 0.12).

CONCLUSION

In our study, it was observed that medical therapy was effective and safe in patients with giant prolactinomas. The use of surgical treatment should be limited to prolactinomas with compression or post-resistance to medical treatment in serious cases.

Hyperprolactinemia in clinical non-functional pituitary macroadenomas: A STROBE-compliant study

Hyperprolactinemia is a prevalent endocrine disorder presented in patients with non-functional pituitary adenomas (NFPAs). However, the mechanism involved in hyperprolactinemia in NFPA is not fully illustrated. The current study aims to investigate predictors for hyperprolactinemia in NFPA via analyzing relevant clinical features. Thus, in this study, a cohort of 214 cases with integrated medical records was retrospectively analyzed concerning clinical, pathological, and endocrinological studies before and after surgery.Hyperprolactinemia happened in 93 cases (43.5%). Women (adjust odds ratio [OR] = 3.093; P < .01), age of patients (adjust OR = 0.951; P < .01), and serum free tetraiodothyronine (FT4) level (adjust OR = 0.882; P = .02) were independent predictors for developing preoperative hyperprolactinemia. Tumor size and hypopituitarism had no impact on hyperprolactinemia. During a median follow-up of 43.5 (range, 22-80) months, 83.9% patients with preoperative hyperprolactinemia experienced prolactin (PRL) normalization. Preoperative PRL level (adjusted OR = 1.741, P = .03) was the exclusive predictor for PRL normalization after adjusting for tumor volume, preoperative serum FT4 concentration, and postoperative residual. The PRL normalization rate of patients with lower PRL level (<2.35-fold upper limit of normal range) was 95.2% and decreased to 65.5% for patients with higher PRL level.In conclusion, our results suggest existence of potentially alternative mechanisms underlying hyperprolactinemia in NFPAs, like the discrepancy of sex and age and the negative feedback of FT4. Preoperative PRL is a predictor for postoperative PRL normalization, which is of clinically relevant for postoperative management of NFPAs.

Temozolomide cytoreductive treatment in a giant cabergoline-resistant prolactin-secreting pituitary neuroendocrine tumor

Dopamine agonists (DAs, especially cabergoline) are recommended as first-line treatment in patients with prolactin-secreting pituitary adenomas, to reduce hormone secretion and tumor size. Pituitary surgery, suggested in nonresponsive patients, cannot achieve a gross total resection or is not feasible in some cases. Temozolomide (TMZ) has been proposed in patients with aggressive pituitary neuroendocrine tumors (PitNETs) who do not respond to conventional treatments. We present a 47-year-old man with a giant (70×51×64 mm) prolactin-secreting PitNET. Cabergoline treatment (at first 1.5 mg/week, and then increased to 3.5 mg/week after 3 months) achieved prolactin suppression; however, magnetic resonance revealed a stable mass. After explanation of surgical complications, the patient rejected the procedure. Therefore, a primary neoadjuvant cytoreductive TMZ treatment was discussed during a meeting of the Pituitary Multidisciplinary Team, and added to cabergoline. After 13 cycles of TMZ (1 year of treatment), we observed dramatic reduction of the PitNET (from 18 cm of adenoma to 6 cm of necrotic tissue). MRI performed 4, 12, and 18 months after TMZ discontinuation revealed a stable residual PitNET, and 1.5 mg/week of cabergoline has been continued until today. Recently, the criteria for developing Pituitary Tumors Centers of Excellence have been proposed, indicating that a multidisciplinary team is the best care for patients. Surgery, rejected by the patient, could only achieve a partial resection; therefore, we decided to combine TMZ and cabergoline. An early initiation of TMZ could be considered in selected cases, especially when surgery could be only partially effective.

Clinical Features, Therapeutic Trends, and Outcome of Giant Prolactinomas: A Single-Center Experience Over a 12-Year Period

Background:

Management of giant prolactinomas presents a different challenge than the management of traditional prolactinomas.

Objective:

The aim of this study was to report the largest long-term single-center study of giant prolactinomas to analyze their clinical features; define epidemiological characteristics, comorbidities, complications, treatment outcomes; and to demonstrate our experience with long-term cabergoline (CAB) treatment of these giant tumors.

Methods:

A retrospective case study and clinical review of patients presenting with giant prolactinomas in the pituitary clinic at King Fahad Medical City (KFMC), Riyadh, Saudi Arabia, in the period between 2006 and 2018 were included in the study. Of the charts reviewed, 33 patients (24 men; 9 women) with age of diagnosis between 18 and 63 years (mean = 37.21 years) met the selection criteria for giant prolactinomas.

Result:

The most common presenting features include headache (87.8%), visual defects (69.7%), and hypogonadism (51.5%). The baseline means serum prolactin (PRL) level was extremely high for both sexes (95 615.03 nmol/L), which eventually decreased by as much as 95.4% after CAB treatment. Serum PRL concentrations completely normalized in 11 patients and significantly reduced in 22 patients. The mean tumor volume at baseline was 42.87 cm³, whereas the mean posttreatment tumor volume was 3.42 cm³ (no residual tumor in 2 patients, while in others, it ranged from 0.11 to 16.7 cm³) at the last follow-up visit. The mean change in tumor volume was 88.84%. Tumor volume decreased by an average of 92% for men and 80.4% for women. One patient had no tumor size change with CAB (3.5 mg thrice a week) or radiotherapy and required surgery. The response rate (remission after medical therapy alone) in this series was 84.84%.

Conclusions:

Findings reinforce results from our previous study that CAB provides dramatic clinical improvements with an excellent safety profile. The CAB should, therefore, be considered as the primary therapy for giant prolactinomas.

Fertility issues in aggressive pituitary tumors

The management of aggressive pituitary adenomas represents a special clinical challenge, and usually involves a combination of surgery, radiotherapy and pharmacological agents to control tumor growth and hormone abnormalities. Fertility is commonly affected in these patients due to compressive effects of the tumor, pituitary hormone dysfunction or as a result of the multiple therapies. The initial approach to restore fertility involves the reduction of tumor volume by the use of dopamine agonists in prolactinomas and by surgery in other pituitary adenomas. Somatostatin analogues are alternative options for GH, ACTH and TSH-secreting tumors. When present, pituitary deficiencies should be appropriately treated, particularly GH deficiency that has been associated with poor pregnancy rates in hypopituitary patients. Other therapies for aggressive pituitary tumors, such as invasive surgery, radiotherapy and temozolamide, may lead to infertility. In such cases, fertility preservation strategies might be considered and discussed with the patient desiring conception before or during treatment. In men and women with hypogonadotropic hypogonadism, administration of gonadotropins or pulse GnRH has resulted in satisfactory pregnancy rates. If spontaneous gestation is not achieved, assisted reproduction techniques can be employed as the last line of treatment. In any context, pre-conception counseling and care are essential as pregnancies in women with aggressive pituitary tumors should always be considered high risk.

Prolactinomas in males: any differences?

CONTEXT

Prolactinomas in men are usually large and invasive, presenting with signs and symptoms of hypogonadism and mass effects, including visual damage. Prolactin levels are high, associated with low testosterone, anemia, metabolic syndrome and if long-standing also osteoporosis.

RESULTS

Medical treatment with the dopamine agonist, cabergoline, became the preferred first-line treatment for male prolactinomas as well as for giant tumors, leading to prolactin normalization in ~ 80% of treated men, and tumor shrinkage, improved visual fields and recovery of hypogonadism in most patients. Multi-modal approach including surgery and occasionally radiotherapy together with a high-dose cabergoline is saved for resistant and invasive adenomas. Experimental treatments including temozolomide or pasireotide may improve clinical response in men harboring resistant prolactinomas.

CONCLUSIONS

Compared to other pituitary adenomas, secreting and non-secreting, where pituitary surgery is the recommended first-line treatment, men with prolactinomas will usually respond to medical treatment with no need for any additional treatment.

Pathology of prolactinomas: any predictive value?

Lactotroph adenomas, also called prolactinomas and prolactin-secreting adenomas, constitute nearly 80% of functioning pituitary tumors and about 30-50% of all adenomas in the clinical practice. Lactotroph adenomas occur in the general population at a prevalence of 45/100,000, are more common in women, but also involve men and children of both sexes. Most lactotroph adenomas are microadenomas occurring in reproductive-age women who present with oligo/amenorrhea, galactorrhea, and infertility. In men and elderly women, lactotroph adenomas are usually macroadenomas and are most commonly associated with symptoms of a tumoral mass, including headaches, neurologic defects, and visual loss. Although clinical and laboratory features may differ depending on patient's gender and age, the histopathology of the tumors is similar. Lactotroph adenomas are histologically classified into three subtypes: the common sparsely granulated lactotroph adenoma, and the rare densely granulated lactotroph adenoma and acidophilic stem cell adenoma. We will review the main pathological features of the lactotroph adenomas and some of their characteristics that may predict biological behavior and responsiveness to treatment.

Mammosomatotroph and mixed somatotroph-lactotroph adenoma in acromegaly: a retrospective study with long-term follow-up

PURPOSE

Although well-documented from pathological aspect, the clinical features and outcomes of acromegaly with mammosomatotroph (MSA) and mixed somatotroph-lactotroph adenoma (MSLA) are seldom reported. Thus, in this study, we analyzed and reported the clinical data about MSAs and MSLAs.

METHODS

We retrospectively reviewed medical records of patients with acromegaly in our institution during 2008-2017. Growth hormone (GH)-secreting adenomas were categorized into pure somatotroph adenoma (PSA), MSA and MSLA based on inclusion and exclusion criteria. Clinical information and treatment outcomes during follow-up were analyzed by univariate and multivariate methods.

RESULTS

Among 94 patients within this cohort, PSAs, MSAs, and MSLAs accounted for 53, 28 and 13 cases, respectively. MSAs often had smaller size, lower frequency of cavernous sinus invasion and higher gross total resection (GTR) rate. MSLAs were characterized by bigger tumor size, higher frequency of preoperative hyperprolactinemia, and lower GTR rate. Thus, MSLAs had worse long-term biological remission rate than MSAs and PSAs (15.4% vs. 50.0% and 26.4%, p = 0.0371). Gender (male, OR = 0.784, p = 0.011) and tumor volume (OR = 0.784, p = 0.020) were independent predictors for long-term biological remission in binary logistic regression. Subgroup analyses indicated that postoperative nadir GH level (GH-7, HR = 1.242, p = 0.001) was the only risk factor for tumor recurrence for patients with GTR.

CONCLUSIONS

Our results provide valuable insights into clinicopathological features of acromegaly. MSAs were relatively smaller lesions with better prognosis. MSLAs were more aggressive with massive size, invasiveness and preoperative hyperprolactinemia. Tumor size and GH-7 were significantly associated with biological remission and tumor relapse after GTR, respectively.

[Clinical and functional characteristics of giant pituitary adenomas in the population of patients in the Moscow region]

Benign pituitary tumors are the most common sellar neoplasms. Lesions larger than 39 mm in the maximum dimension are called giant. They are rare, and, therefore, there are few data on the clinical and morphological features of giant pituitary tumors with different hormonal activity.

AIM

The aim of this study was to identify the clinical and functional features of giant pituitary tumors with different hormonal activity.

MATERIAL AND METHODS

We analyzed data of clinical, laboratory, and instrumental examinations of 351 patients diagnosed with pituitary macroadenomas at the Moscow Regional Research Clinical Institute in the period between 2008 and 2017: there were 144 hormonally inactive pituitary adenomas and 207 hormonally active pituitary adenomas (65 prolactinomas and 142 somatotropinomas).

RESULTS AND DISCUSSION

Among 351 patients with pituitary macroadenomas, there were 32 (9.1%) giant adenoma cases: 18 (12.5%) 144 patients with hormonally inactive pituitary adenomas and 14 (6.8%) 207 patients with hormonally active pituitary adenomas 6 (3.9%) 65 prolactinomas and 6 (2.9%) 142 somatotropinomas. The volume of giant adenomas was somewhat larger among somatotropinomas 48 926 [35 067; 97 650] mm³ and prolactinomas 36 872 [15 281; 75 102] mm³ compared to that of hormonally inactive pituitary adenomas 26 933 [21 910; 42 895] mm³. Tumors had predominant suprasellar and posterosellar growth (31 (97.8%) and 29 (90.6%) cases, respectively). The most common first patient complaints were visual impairments (59.4%) and headache and/or dizziness (43.8%). Correspondingly, due to these complaints, 16 (50%) patients first consulted an ophthalmologist. Hypopituitarism detected before any treatment was present in 16 (50%) patients.

CONCLUSION

In most cases, visual impairments and headaches/dizziness were the first manifestations of giant pituitary adenomas; therefore, ophthalmologists and neurologists should always refer patients with these complaints to MRI. Patients with identified giant pituitary tumors should be referred to an endocrinologist for exclusion of hypopituitarism and, if necessary, timely prescription of hormonal therapy.

Status epilepticus induced by treatment with dopamine agonist therapy for giant prolactinoma: a case report

Background

Dopamine agonists are the standard first-line medical therapy for prolactinoma. We report a rare case of giant prolactinoma with a first epileptic seizure due to rapid reduction of the tumor as a complication of dopamine agonist therapy.

Case presentation

A 27-year-old Japanese man presented to our institution with a history of visual disturbance for 1 year and general fatigue for 3 months. Magnetic resonance imaging showed a tumor that arose from the pituitary and extended to the bilateral anterior skull base, the clivus, and the cavernous sinus, with compression of the optic chiasm and the bilateral frontal and temporal lobes. On the basis of the patient’s serum concentration of prolactin, we diagnosed a prolactinoma and started dopamine agonist therapy with cabergoline. The patient had a general seizure immediately after starting dopamine agonist therapy and required general anesthetic treatment following the rapid reduction of the tumor. We speculated that the rapid reduction of the tumor resulted in the retraction of the surrounding brain structure, and the epileptic seizure was then induced by dopamine agonist therapy.

Conclusions

We report a rare case of giant prolactinoma with a first epileptic seizure immediately after the initiation of dopamine agonist therapy. Clinicians need to be aware that the rapid reduction of a giant prolactinoma by dopamine agonist therapy may cause an epileptic seizure.

Giant Prolactinoma Causing Hydrocephalus and Intracranial Hypertension as First Manifestations of Multiple Endocrine Neoplasia Type 1

Context: Overall, giant prolactinomas are rare tumors (4%), especially those larger than 60 mm (1%). Despite the predominance of macroadenoma documented in multiple endocrine neoplasia type 1 (MEN1)-related prolactinoma, only three giant prolactinoma cases were described so far (size > 40 mm and prolactin > 1,000 ng/mL). None of them was larger than 60 mm or presented hydrocephalus or intracranial hypertension (ICH) as initial manifestation of MEN1. Case Description: A 21-years-old man presented with ICH as the first clinical manifestation of MEN1. He harbored a MEN1 germline mutation but refused periodic vigilance after normal hormonal screening at age 14 years. During investigation, magnetic resonance imaging (MRI) of the skull showed an expansive sellar/parasellar lesion (75 × 44 × 36 mm) with moderate to severe supratentorial obstructive hydrocephalus and an extremely high serum prolactin (PRL) of 10,800 ng/mL, without combined hypersecretion of other pituitary hormones. He was diagnosed with giant prolactinoma, and cabergoline was initiated. The patient evolved with early improvement of clinical complaints for hydrocephalus and ICH and PRL reached normal values (11 ng/mL) in association with significant tumoral shrinkage after 18 months on cabergoline. After 2 months of cabergoline, cerebrospinal fluid leakage was diagnosed and corrective surgery was provided. The mean dose of cabergoline was 3 mg/week throughout treatment. Conclusion: We reported the first case with hydrocephalus and ICH as the initial clinical manifestation of a giant prolactinoma in MEN1. From our knowledge, this is the largest MEN1-related prolactinoma reported so far. Notably, all four MEN1-related giant prolactinomas cases reported were younger than 21 years strengthening the importance to routine MEN1 genetic testing for prolactinoma in this age group. Also, they all had initial effective response with dopamine agonist ensuring this drug as first-line treatment for MEN1-related giant prolactinoma. However, the scarce number of treated patients and progression of cabergoline resistance in two of them suggest strict surveillance.

Management of Dopamine Agonist-Resistant Prolactinoma

Dopamine agonists are usually very effective in the treatment of prolactinomas. Nonetheless, a subset of individuals does not respond satisfactorily to these agents, and this resistance is characterized by failure to achieve normoprolactinemia and a 30% or more reduction in maximal tumor diameter (in the case of macroprolactinoma) under maximally tolerated doses. The overall prevalence of dopamine agonist resistance is 20-30% for bromocriptine (BRC) and around 10% for cabergoline (CAB). The 2 main predictive factors are male gender and tumor invasiveness. The management of drug-resistant prolactinomas includes several options. Any BRC-resistant patient should be switched to CAB which will normalize prolactin in 80% of patients. As long as adverse effects do not develop, dose escalation of CAB is reasonable, with the expectation that subsequent dose reduction will be possible. Echocardiographic monitoring is advised in such patients because of the potential association with cardiac valvular fibrosis. Also, maintaining maximal CAB doses at 3.5 mg/week may lead to progressive hormonal control in a significant proportion of patients. Complete resistance to CAB is infrequent. In a study of 122 patients with a macroprolactinoma, only 7 (6%) could not achieve control despite maximal CAB doses for > 12 months. A large resistant prolactinoma is also an indication for transsphenoidal neurosurgery, aiming at a debulking which may improve postoperative medical control. For patients who harbor aggressive prolactinomas, radiotherapy may be considered. However, normal prolactinemia will eventually occur in only one-third of patients after many years. Finally, temozolomide may be a therapeutic option in malignant/aggressive prolactinomas.

Aggressive and Malignant Prolactinomas

Prolactin-secreting tumors (prolactinomas) represent the most common pituitary tumor type, accounting for 47-66% of functional pituitary tumors. Prolactinomas are usually benign and controllable tumors as they express abundant levels of dopamine type 2 receptor (D2), and can be treated with dopaminergic drugs, effectively reducing prolactin levels and tumor volume. However, a proportion of prolactinomas exhibit aggressive features (including invasiveness, relevant growth despite adequate dopamine agonist treatment, and recurrence potential) and few may exhibit metastasizing potential (carcinomas). In this context, the clinical, pathological, and molecular definitions of malignant and aggressive prolactinomas remain to be clearly defined, as primary prolactin-secreting carcinomas are similar to aggressive adenomas until the presence of metastases is detected. Indeed, standard molecular and histological analyses do not reflect differences between carcinomas and adenomas at a first glance and have limitations in prediction of the aggressive progression of prolactinomas, wherein the causes underlying the aggressive behavior remain unknown. Herein we present a comprehensive, multidisciplinary review of the most relevant epidemiological, clinical, pathological, genetic, biochemical, and molecular aspects of aggressive and malignant prolactinomas.

Giant Prolactinomas

Prolactin-secreting adenomas (prolactinomas) are the most common secreting adenomas of the pituitary. Microprolactinomas (diameter <10 mm) are frequently diagnosed in women, whereas macroprolactinomas (maximum diameter ≥10 mm) are generally seen in men. Most macroprolactinomas measure between 10 and 40 mm. Giant prolactinomas, measuring >40 mm, are rare, accounting for only 1-5% of all prolactinomas. Although generally benign, giant prolactinomas are aggressive and invasive, extending into the suprasellar region and also involving the cavernous sinuses. The optic chiasm is frequently involved, which leads to visual damage, and patients occasionally suffer from ophthalmoplegia. Long-term (usually lifetime) therapy with high-dose dopamine agonists (cabergoline or bromocriptine), together with pituitary surgery in some cases and radiotherapy if required, can achieve biochemical remission, tumor control, and clinical improvement in most patients.

Giant prolactinoma, germline BRCA1 mutation, and depression: a case report

Background

Giant prolactinomas are very rare pituitary tumors that may exhibit an aggressive behavior and present with a life-threatening condition.

Case presentation

A 25-year-old white woman was admitted to our hospital with a headache, psychomotor retardation, reduced vision, and loss of autonomy in daily activities. Her past medical history was significant for having oligomenorrhea and a depressive syndrome since her mother’s death. She also had a breast cancer gene 1 (BRCA1) mutation and a family history of breast cancer. She had marked hyperprolactinemia (7615 ng/dL), central hypocortisolism, growth hormone deficiency, and a giant pituitary tumor (52 × 30 × 33 mm) which was shown in magnetic resonance imaging with obstructive hydrocephalus, requiring emergency surgery. Treatment with cabergoline led to a 99.8% reduction in serum prolactin levels and significant tumor shrinkage. Her depressive symptoms progressively improved and psychiatric drugs were withdrawn after 3 months of cabergoline treatment. Currently, she is being followed in Endocrinology, Neurosurgery, and Neurophthalmology out-patient clinics and in a breast cancer unit. Careful monitoring, support, and follow-up will be essential throughout this patient’s life.

Conclusions

This case is a rare presentation of a giant prolactinoma in a young woman, who presented a life-threatening event. She also had an unexpected association between diseases or symptoms that may have contributed to the delay in diagnosis. Given the concomitant presence of a giant prolactinoma, a BRCA1 mutation, and depressive symptoms, a possible association was hypothesized. The breast cancer risk in a BRCA1 mutation carrier and the possible interference of hyperprolactinemia and life events were also discussed. However this hypothesis requires further investigation.

Medically induced CSF rhinorrhea following treatment of macroprolactinoma: case series and literature review

PURPOSE

Although several reports have addressed cerebrospinal fluid (CSF) rhinorrhea following dopamine agonist (DA) therapy of macroprolactinomas, further study is warranted for this relatively uncommon entity. Toward this aim, our retrospective series and review of literature further clarifies recommendations in treatment of this rare problem.

METHODS

We retrospectively reviewed all macroprolactinoma cases in our hospital for a 15-year period. Our systematic search of PubMed identified original articles and reviews of all macroprolactinoma cases with an associated medication-induced CSF leak.

RESULTS

Five patients with drug-induced CSF leak were identified; four of these patients received cabergoline therapy an average of 6 weeks before the onset of rhinorrhea and then underwent surgical repair of the CSF leak. Of 35 published studies included, we identified 60 patients with medication-induced CSF leak. Medical therapy included bromocriptine in 34 patients, cabergoline in 21 patients, and use of both DAs in two patients. Three cases did include complete diagnostic and treatment data. Median time from initiation of the DA treatment to occurrence of rhinorrhea was 6 weeks. For CSF rhinorrhea, 49 patients underwent surgical repair (38 by the transnasal approach) and seven patients were treated nonoperatively.

CONCLUSION

Baseline skull base erosion in macroprolactinomas in combination with subsequent tumor shrinkage induced by DA therapy may result in spontaneous CSF rhinorrhea. Therefore, such patients should be advised about and monitored for this potential setback. Once CSF leak is diagnosed, prompt treatment must be carried out to avoid infectious complications. Transnasal surgery appears the most effective therapeutic approach.

Giant Prolactinoma of Young Onset: A Clue to Diagnosis of MEN-1 Syndrome

Multiple endocrine neoplasia (MEN) type 1 syndrome is an autosomal dominant disorder caused by germline mutations in MEN1 gene, characterized by tumours in endocrine and nonendocrine organs. Giant prolactinoma is defined as tumours larger than 40mm with very high prolactin secretion. We report two unrelated Sri Lankan patients (8-year-old boy and a 20-year-old female) who presented with giant prolactinomas with mass effects of the tumours. The female patient showed complete response to medical therapy, while the boy developed recurrent resistant prolactinoma needing surgery and radiotherapy. During follow-up, both developed pancreatic neuroendocrine tumours. Genetic analysis revealed that one was heterozygous for a nonsense mutation and other for missense mutation in MEN1 gene. Screening confirmed familial MEN-1 syndrome in their families. High clinical suspicion upon unusual clinical presentation prompted genetic evaluation in these patients and detection of MEN1 gene mutation. Pituitary adenomas in children with MEN-1 syndrome are larger tumours with higher rates of treatment resistance. This report emphasizes importance of screening young patients with giant prolactinoma for MEN-1 syndrome and arranging long-term follow-up for them expecting variable treatment outcomes. Sri Lanka requires further studies to describe the genotypic-phenotypic variability of MEN-1 syndrome in this population.

Giant pituitary adenoma: histological types, clinical features and therapeutic approaches

Giant pituitary adenomas comprise about 6-10% of all pituitary tumors. They are mostly clinically non-functioning adenomas and occur predominantly in males. The presenting symptoms are usually secondary to compression of neighboring structures, but also due to partial or total hypopituitarism. Functioning adenomas give rise to specific symptoms of hormonal hypersecretion. The use of dopamine agonists is considered a first-line treatment in patients with giant macroprolactinomas. Somatostatin analogs can also be used as primary treatment in cases of growth hormone and thyrotropin producing giant adenomas, although remission of the disease is not achieved in the vast majority of these patients. Neurosurgical treatment, either through transsphenoidal or transcranial surgery, continues to be the treatment of choice in the majority of patients with giant pituitary adenomas. The intrinsic complexity of these tumors requires the use of different therapies in a combined or sequential way. A multimodal approach and a therapeutic strategy involving a multidisciplinary team of expert professionals form the basis of the therapeutic success in these patients.

Beat the giant: case of a giant prolactinoma during pregnancy on cabergoline

Giant prolactinomas are a rare entity; during pregnancy, the risk for complications associated with these tumors is higher. Here, we report a case of a young woman who had an invasive, giant prolactinoma post resection with residual disease who became pregnant. This patient was treated with cabergoline to prevent tumor expansion in pregnancy, resulting in the uneventful delivery of a healthy baby boy.

Controversial issues in the management of hyperprolactinemia and prolactinomas - An overview by the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism

Prolactinomas are the most common pituitary adenomas (approximately 40% of cases), and they represent an important cause of hypogonadism and infertility in both sexes. The magnitude of prolactin (PRL) elevation can be useful in determining the etiology of hyperprolactinemia. Indeed, PRL levels > 250 ng/mL are highly suggestive of the presence of a prolactinoma. In contrast, most patients with stalk dysfunction, drug-induced hyperprolactinemia or systemic diseases present with PRL levels < 100 ng/mL. However, exceptions to these rules are not rare. On the other hand, among patients with macroprolactinomas (MACs), artificially low PRL levels may result from the so-called "hook effect". Patients harboring cystic MACs may also present with a mild PRL elevation. The screening for macroprolactin is mostly indicated for asymptomatic patients and those with apparent idiopathic hyperprolactinemia. Dopamine agonists (DAs) are the treatment of choice for prolactinomas, particularly cabergoline, which is more effective and better tolerated than bromocriptine. After 2 years of successful treatment, DA withdrawal should be considered in all cases of microprolactinomas and in selected cases of MACs. In this publication, the goal of the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism (SBEM) is to provide a review of the diagnosis and treatment of hyperprolactinemia and prolactinomas, emphasizing controversial issues regarding these topics. This review is based on data published in the literature and the authors' experience.

Cabergoline versus bromocriptine for the treatment of giant prolactinomas: A quantitative and systematic review

The aim of this study is to compare the efficacy of bromocriptine (BRC) versus cabergoline (CAB) in patients with giant prolactinomas. We searched MEDLINE, EMBASE, CENTRAL and Clinical Trials.gov for studies dated before March 1st, 2016, that used BRC or CAB for the treatment of patients with giant prolactinomas. Specific eligibility criteria were set to identify articles and cases. The selected articles were reviewed, and the data were extracted for analysis. The compared outcomes included tumor shrinkage, tumor response, normalization of prolactin (PRL) level, and visual field defect (VFD) improvement. Gender differences were also considered. Differences between the groups were assessed using Student's t test and the chi-square test. Two hundred and forty-five records were identified, and 10 articles and 104 cases met the inclusion criteria. Based on our analysis, CAB is significantly better than BRC in normalizing PRL levels in patients, especially males, with giant prolactinomas (69.4% versus 31.7%, p = 0.01). However, there was no significant difference between the two drugs in terms of tumor shrinkage, tumor response and VFD improvement (p > 0.05) in male or female patients. CAB exhibits significantly better efficacy than BRC in the normalization of PRL levels in male patients with giant prolactinomas. Regarding tumor reduction and VFD improvement, both drugs are comparably effective for patients of both genders. This quantitative and systematic review provides preliminary evidence in favor of CAB as a medical therapy for treating giant prolactinomas in male patients, especially those with extremely high PRL levels.

Broad clinical spectrum and diverse outcomes of prolactinoma with pediatric onset: medication-resistant and recurrent cases

Prolactinoma is a benign tumor of the pituitary gland that rarely occurs in children and adolescents; thus, the clinical spectrum and long-term prognosis in these patients remain unknown. This study was performed to investigate the long-term outcomes of medical treatment and the prognostic factors for remission and relapse in children and adolescents with prolactinoma. Three male subjects and four female subjects between the ages of 7- and 17-years-old were included in this study. The mean initial serum prolactin level was 443 ± 251.8 ng/mL (range, 152-946 ng/mL). During the follow-up period (range, 0.6-20 years), a dopamine agonist was administered, and surgery or radiotherapy was performed in cases of resistance to medical treatment or relapse. Unlike female subjects with macroadenoma who often exhibit a good clinical course, two male subjects with early onset macroadenoma presented with visual disturbances. These subjects showed resistance to medical therapy and relapsed, eventually requiring surgical removal and radiotherapy; one of the subjects manifested a metastatic thrombus in the internal jugular vein. In conclusion, pediatric prolactinoma exhibits a broad clinical spectrum, a relatively high incidence of macroadenoma, resistance to medical therapy, and frequent tumor relapses. In addition, a poor prognosis appears to be correlated with male sex, age at disease onset, and histopathological characteristics.

[Cerebrospinal fluid rhinorrhea in primary treatment of large and giant prolactinomas with dopamine agonists]

At present, pharmacological therapy of prolactinomas with dopamine agonists (DAs) is considered the treatment of choice. In most cases, giant prolactinomas respond to treatment with dopamine agonists and decrease in size during the first months of the treatment. One of the rare but dangerous complications of conservative treatment of prolactinomas with invasive growth is cerebrospinal fluid rhinorrhea.

MATERIAL AND METHODS

We present a retrospective analysis of 15 patients with macropropactinomas who underwent surgery for cerebrospinal fluid rhinorrhea developed due to primary therapy with dopamine agonists at the Burdenko Neurosurgical Institute (BNI) in the period between 2005 and 2015. All patients had large and giant tumors (according to the classification adopted at the BNI). When cerebrospinal fluid rhinorrhea was detected, patients were hospitalized to the BNI for examination, detection of a CSF fistula, reconstruction of a defect, and resection (if possible) of the tumor.

RESULTS

In the period between 2005 and 2015, 15 patients (8 males and 7 females) with prolactinomas of a large and giant size at the onset of conservative therapy underwent surgery for cerebrospinal fluid rhinorrhea at the BNI. All patients underwent transnasal reconstruction of a skull base defect, with 13 out of 15 patients undergoing simultaneous resection of the tumor. After tumor resection, reconstruction was performed using auto-fat, fascia, and glue (in 8 cases). In the remaining cases, apart from auto-fat, fascia, and glue, a mucoperiosteal flap and auto-bone were used. Fourteen patients were followe-up. In 13 cases, there was no relapse of cerebrospinal fluid rhinorrhea after skull base reconstruction. In 1 case, there was a relapse of cerebrospinal fluid rhinorrhea.

CONCLUSION

Conservative treatment of patients with giant prolactinomas should be performed under regular control of ENT doctors and neurosurgeons for timely detection and surgical treatment of cerebrospinal fluid rhinorrhea.