Transsphenoidal surgery for microprolactinomas in women: results and prognosis

Presurgical Medical Treatment in Prolactinomas: Surgical Implications and Pathological Characteristics From 290 Cases

OBJECTIVE

To review experience regarding the treatment of prolactinomas by endoscopic endonasal surgery focusing on the association between presurgical dopamine agonist (DA) treatment and perioperative outcomes, surgical morbidities, endocrine outcomes, and pathological characteristics.

METHODS

A single-center series of 290 cases was analyzed retrospectively and clinical data were collected. Intratumoral collagen content was assessed by Masson trichrome staining.

RESULTS

Tenacious tumor consistency (27.8% vs 9.8%, P < .001) was more common in DA-pretreated patients compared with patients who underwent initial surgery. Moreover, DA-pretreated macroadenomas presented more intraoperative blood loss (200 [100-400] mL vs 175 [100-300] mL; P = .014), longer surgical duration (177 ± 95 minutes vs 154 ± 57 minutes; P = .043), and more surgical morbidities (19.4% vs 8.9%; P = .034). Additionally, DA-pretreated macroadenomas presented a higher collagen volume fraction than that of the initial surgery group (23.6 ± 2.2% vs 13.2 ± 2.1%; P = .001). Correlation analysis revealed a close correlation between collagen volume fraction and the cumulative dose of bromocriptine (BRC) in macroadenomas (r = 0.438, P < .001). Regarding endocrine outcomes, DA-pretreated microadenomas showed a lower proportion of initial remission compared with patients who underwent initial surgery (86.7% vs 100%, P = .047).

CONCLUSION

This study described increased surgical difficulty and inferior endocrine outcomes associated with tumor fibrosis secondary to presurgical BRC treatment in prolactinomas. Neurosurgeons should note that presurgical BRC treatment may render subsequent surgery more challenging.

Perioperative hormone level changes and their clinical implications in patients with pituitary adenoma: a retrospective study of 428 cases at a single center

Objective

This study employs case data analysis to elucidate alterations in hormone levels pre and post-surgery among patients with pituitary adenoma. Moreover, it investigates the influence of various associated factors on endocrine function.

Methods

A retrospective analysis was conducted on clinical data from 428 patients who underwent surgical treatment within a short period at a single center. Statistical methods were employed to examine detailed hormone level fluctuations before and after surgery in patients with pituitary adenoma, along with their interrelations with different factors.

Results

Between January 2016 and October 2022, a total of 428 consecutive patients with pituitary adenoma underwent surgical treatment. Of these, 232 were males and 196 were females, with an average age of 45.91 years (range: 16-84, standard deviation: 12.18). Univariate analysis indicated that females exhibited a higher susceptibility to preoperative endocrine dysfunction (p < 0.05). Conversely, males, patients with larger tumor volumes, and older patients were more prone to preoperative pituitary insufficiency. Postoperatively, the most substantial remission rate occurred in prolactin (77.4%), followed by growth hormone (GH) (71.8%) and cortisol (4/6). The highest recovery rate in functions was observed in growth hormone secretion function (80%), followed by pituitary-adrenal axis hormone secretion function (56.3%) and pituitary-thyroid axis hormone secretion function (47.5%). The most noteworthy incidence of newly developed postoperative endocrine deficiencies was found in the pituitary-adrenal axis (31.8%), while the occurrence rates of deficiencies in other axes were relatively low. The elevated postoperative remission rate of growth hormone correlated with a higher surgical resection rate and lower preoperative growth hormone levels. Additionally, lower preoperative prolactin levels corresponded to a higher remission rate of prolactin postoperatively. Furthermore, the restoration of postoperative thyroid hormone secretion function was associated with higher preoperative free thyroxine levels. Reduced postoperative cortisol secretion function was linked to multiple surgeries and an extended interval between hormone retesting and surgery.

Conclusion

Surgical intervention effectively ameliorates endocrine disorders in pituitary adenoma patients, thereby mitigating symptoms and enhancing their quality of life. Preoperative management of growth hormone and prolactin levels facilitates an increased remission rate of these hormones post pituitary adenoma surgery. Patients displaying preoperative thyroid hormone secretion dysfunction should be considered for active supplementation therapy. Whenever feasible, complete tumor resection is recommended. For patients undergoing reoperation or multiple surgeries, vigilant postoperative cortisol monitoring and supplementation should be thoughtfully administered.

The Combination of Dopamine Agonist Treatment and Surgery May Be the Best Option in Challenging Prolactinoma Cases: A Single-Centre Experience

OBJECTIVE

To investigate the initial and long-term remission rates, factors related to remission, secondary treatments, and outcomes for patients with prolactinoma who underwent endoscopic transsphenoidal surgery (ETSS).

METHODS

The medical files of the 45 prolactinoma patients who underwent ETSS between 2015 and 2022 were retrospectively reviewed. Relevant demographic and clinical data were obtained.

RESULTS

Twenty-one (46.7%) patients were female. The median age of patients at ETSS was 35 (interquartile range, 22.5-50) years. The median clinical follow-up of patients was 28 (interquartile range 12-44) months. The initial surgical remission rate was 60%. Recurrence was detected in 7 patients (25.9%). Postoperative dopamine agonists were used in 25 patients, radiosurgery in 2, and second ETSS in 4 patients. After these secondary treatments, the long-term biochemical remission rate was 91.1%. The factors associated with failure in surgical remission are: male gender, older age, higher tumor size, advanced Knosp and Hardy stage, and elevated prolactin level at diagnosis. A prolactin level of <19 ng/mL in the first postoperative week predicted surgical remission with a sensitivity of 77.8% and a specificity of 70.6% in patients who received preoperative dopamine agonist treatment.

CONCLUSIONS

In macro adenomas and/or giant adenomas with cavernous sinus invasion, and significant suprasellar extension, which constitutes the difficult part of prolactinoma treatment, neither surgery nor medical treatment alone may be effective enough. Both treatment modalities should be carried out together by a team of neurosurgery and endocrinology in the management of these patients.

Treatment of Prolactinoma

Prolactinomas are the commonest form of pituitary neuroendocrine tumor (PitNET), representing approximately half of such tumors. Dopamine agonists (DAs) have traditionally been the primary treatment for the majority of prolactinomas, with surgery considered the second line. The aim of this review is to examine the historical and modern management of prolactinomas, including medical therapy with DAs, transsphenoidal surgery, and multimodality therapy for the treatment of aggressive prolactinomas and metastatic PitNETs, with an emphasis on the efficacy, safety, and future directions of current therapeutic modalities. DAs have been the mainstay of prolactinoma management since the 1970s, initially with bromocriptine and more recently with cabergoline. Cabergoline normalizes prolactin in up to 85% of patients and causes tumor shrinkage in up to 80%. Primary surgical resection of microprolactinomas and enclosed macroprolactinomas performed by experienced pituitary neurosurgeons have similar remission rates to cabergoline. Aggressive prolactinomas and metastatic PitNETS should receive multimodality therapy including high dose cabergoline, surgery, radiation therapy (preferably using stereotactic radiosurgery where suitable), and temozolomide. DAs remain a reliable mode of therapy for most prolactinomas but results from transsphenoidal surgery in expert hands have improved considerably over the last one to two decades. Surgery should be strongly considered as primary therapy, particularly in the setting of microprolactinomas, non-invasive macroprolactinomas, or prior to attempting pregnancy, and has an important role in the management of DA resistant and aggressive prolactinomas.

Extra-Pseudocapsular Transsphenoidal Surgery for Microprolactinoma in Women

A recall for histological pseudocapsule (PS) and reappraisal of transsphenoidal surgery (TSS) as a viable alternative to dopamine agonists in the treatment algorithm of prolactinomas are getting vibrant. We hope to investigate the effectiveness and risks of extra-pseudocapsular transsphenoidal surgery (EPTSS) for young women with microprolactinoma, and to look into the factors that influenced remission and recurrence, and thus to figure out the possible indication shift for primary TSS. We proposed a new classification method of microprolactinoma based on the relationship between tumor and pituitary position, which can be divided into hypo-pituitary, para-pituitary and supra-pituitary groups. We retrospectively analyzed 133 patients of women (<50 yr) with microprolactinoma (≤10 mm) who underwent EPTSS in a tertiary center. PS were identified in 113 (84.96%) microadenomas intraoperatively. The long-term surgical cure rate was 88.2%, and the comprehensive remission rate was 95.8% in total. There was no severe or permanent complication, and the surgical morbidity rate was 4.5%. The recurrence rate with over 5 years of follow-up was 9.2%, and a lot lower for the tumors in the complete PS group (0) and hypo-pituitary group (2.1%). Use of the extra-pseudocapsule dissection in microprolactinoma resulted in a good chance of increasing the surgical remission without increasing the risk of CSF leakage or endocrine deficits. First-line EPTSS may offer a greater opportunity of long-term cure for young female patients with microprolactinoma of hypo-pituitary located and Knosp grade 0-II.

Changes in the Options for Management of Prolactin Secreting Pituitary Adenomas

Objectives Initial therapy for the management of prolactinomas has long been maintained to be medical, consisting of a dopamine agonist. These therapies may have troublesome side effects, and some prolactinomas are resistant to medical therapy regarding lowering prolactin levels or shrinking the tumor. These issues have revived interest in surgery for prolactin-secreting adenomas as an early therapeutic option. We report our analysis of surgery for prolactin microadenomas in women, using the transsphenoidal endoscopic approach.

Design We reviewed a contemporary series of 33 women (mean age = 31.8 years) with microprolactinomas who underwent early surgical intervention, which was a three-dimensional transnasal transsphenoidal endoscopic operation.

Setting The study was conducted at a tertiary academic referral center for pituitary tumors.

Main Outcome Measures Preoperative and postoperative prolactin.

Results Overall, 28 patients had received preoperative dopamine agonists, 24 of these experienced a variety of drug-related side effects, and 4 had tumors that were resistant to lowering prolactin or tumor shrinkage. Preoperative prolactin levels averaged 90.3 ng/mL (range = 30.7–175.8 ng/mL). We observed a 94% normalization rate in postoperative prolactin (mean = 10.08 ng/mL, range = 0.3–63.1 ng/mL). During the follow-up (mean = 33.9 months), five patients had elevated prolactin; four required reinitiation of medical therapy, two had surgical reexploration, and none received radiation therapy. Complications included syndrome of inappropriate antidiuretic hormone secretion (n = 3), transient diabetes insipidus (n = 1), postoperative epistaxis (n = 1), and fat graft site infection (n = 1).

Conclusion This review supports the consideration of transsphenoidal surgery as an early intervention for some women with prolactin-secreting microadenoma. Indications include significant side effects of medical therapy and tumors that do not respond to standard medical management.

Surgical Treatment of Cystic Pituitary Prolactin-Secreting Macroadenomas: A Single Center Study of 42 Patients

This study evaluated the therapeutic effects of surgical treatment of cystic pituitary prolactin-secreting macroadenomas. The clinical data of 42 patients with cystic pituitary prolactin-secreting macroadenomas were retrospectively analyzed. Patients were divided into medication plus surgery and surgery alone groups based on the regularity of bromocriptine treatment before surgery. Both groups underwent extra-pseudocapsular transsphenoidal surgery for tumor resection, and postoperative images and clinical follow-up were retrospectively reviewed. We also evaluated patients who opted for long-term treatment with bromocriptine. In the medication plus surgery group, the long-term surgical cure rate and comprehensive remission rate were 33.3% and 41.7%, while in the surgery alone group they were 69.2% and 80.8%, respectively. No severe or permanent complications occurred, and the surgical complication morbidity rate was 10.5%. The rate of tumor progression during the long-term follow-up was 33.3% and 7.7% in the medication plus surgery and surgery alone groups, respectively. The time required for prolactin levels to return to normal in the surgery alone group was significantly faster and the proportion that returned to normal was significantly higher. Direct surgical treatment after diagnosis combined with postoperative individualized bromocriptine adjuvant therapy had better efficacy in patients with cystic pituitary prolactin-secreting macroadenomas, but its long-term effectiveness requires further follow-up.

Are dopamine agonists still the first-choice treatment for prolactinoma in the era of endoscopy? A systematic review and meta-analysis

Background

For prolactinoma patients, dopamine agonists (DAs) are indicated as the first-line treatment and surgery is an adjunctive choice. However, with the development of surgical technique and equipment, the effect of surgery has improved. The aim of this study was to assess the efficacy and safety of surgery versus DAs in patients with different types of prolactinomas.

Methods

A systematic search of literature using Web of Science, PubMed, Cochrane Library, and Clinical Trial databases was conducted until July 12, 2019. Prolactinoma patients treated with DAs (bromocriptine or cabergoline) or surgery (microscopic or endoscopic surgery) were included. Outcomes included the biochemical cure rate, recurrence rate, prolactin level, improvement rates of symptoms, and incidence rates of complications. A random-effects model was used to pool the extracted data. Qualitative comparisons were conducted instead of quantitative comparison.

Results

DAs were better than surgery in terms of the biochemical cure rate (0.78 versus 0.66), but surgery had a much lower recurrence rate (0.19 versus 0.57). Full advantages were not demonstrated in improvement rates of symptoms and incidence rates of complications with both treatment options. In microprolactinoma patients, the biochemical cure rate of endoscopic surgery was equal to the average cure rate of DAs (0.86 versus 0.86) and it surpassed the biochemical cure rate of bromocriptine (0.86 versus 0.76). In macroprolactinoma patients, endoscopic surgery was slightly higher than bromocriptine (0.66 versus 0.64) in terms of the biochemical cure rate.

Conclusion

For patients with clear indications or contraindications for surgery, choosing surgery or DAs accordingly is unequivocal. However, for patients with clinical equipoise, such as surgery, especially endoscopic surgery, in microprolactinoma and macroprolactinoma patients, we suggest that neurosurgeons and endocrinologists conduct high-quality clinical trials to address the clinical equipoise quantitatively.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41016-022-00277-1.

Postoperative remission of non-invasive lactotroph pituitary tumor: a single-center experience

BACKGROUND

Dopaminergic agonists (DA) are the first-line treatment in lactotroph pituitary tumor but treatment usually needs to be life-long. After surgical transphenoid resection, remission rates range from 60% to 90%, with low morbidity.

OBJECTIVE

The objective was to evaluate outcome of surgical treatment of selected non-invasive prolactinoma, and to identify factors associated with long-term remission.

METHOD

Early postoperative (3 months) and last follow-up data for non-invasive lactotroph tumors operated on in intention-to-cure in our center, between 2008 and 2017 were retrospectively reviewed: prolactin (PRL) level, DA treatment, pituitary function, and MRI data. Remission was defined as PRL plasma level below the upper limit of normal without DA treatment.

RESULTS

Fifty-three of the 60 patients (32 of the 33 microadenomas) were in remission at 3 months and 46 (28/33 microadenomas) at last follow-up 22.7 months (range, 1.1-126.5 months) after surgery. Five-year recurrence-free survival was 77.5% [65.8-91.2]. Male gender, larger tumor size at diagnosis and before surgery and higher plasma PRL level at diagnosis were all significantly associated with lower remission rates on univariate analysis. Transient diabetes insipidus and hyponatremia occurred in 2 and 5 patients respectively. One case of isolated thyrotroph insufficiency was observed. During follow-up, 13 women became pregnant (12 spontaneously).

CONCLUSION

This cohort confirmed the high remission rate of lactotroph tumors after surgery in a selected population, with limited morbidity, and conserved pituitary function in almost all cases.

Cure and Hormonal Control After Prolactinoma Resection: Case Series and Systematic Review

Context

Surgical management of prolactinomas is an important treatment for patients intolerant of dopamine agonist therapy. However, predictors of postoperative outcomes remain unclear.

Object

While transsphenoidal surgical resection (TSSR) is important second-line therapy in prolactinoma patients, predictors of surgical cure and biochemical remission following TSSR remain sparse.

Methods

A retrospective review of prolactinoma patients undergoing TSSR at the USC Pituitary Center from 1995 to 2020 was conducted. Participants were categorized as surgical cure (normalization of serum prolactin without medical treatment), surgical noncure, biochemical control (prolactin normalization with or without adjuvant therapy), and nonbiochemical control. A systematic review of the outcomes of surgically managed prolactinomas was performed.

Results

The 40 female and 16 male participants had an average age of 35.6 years. Prior treatment included transsphenoidal resection (6, 11%) and dopamine agonist treatment (47, 84%). The 40 macroadenomas and 15 microadenomas exhibited suprasellar extension (24, 43%) and parasellar invasion (20, 36%). Fifteen (27%) were purely intrasellar. Gross total resection was achieved in 25 patients (45%) and subtotal in 26 (46%). Surgical cure was achieved in 25 patients (46%) and biochemical control in 35 (64%). Surgical cure was more likely in smaller, noninvasive tumors, those that were fully resected, and patients with lower preoperative (< 1000 ng/mL) and immediately postoperative (< 7.6 ng/mL) prolactin levels. Ten of 26 patients (38%) undergoing adjuvant therapy achieved biochemical control, which was less likely in men and those with higher preoperative prolactin or invasive tumors.

Conclusion

Surgical resection of prolactinomas is a safe procedure that, when offered judiciously, can achieve symptom and/or biochemical control in a majority of patients. A variety of predictors may be useful in advising patients on likelihood of postoperative remission.

Determinants of Surgical Remission in Prolactinomas: A Systematic Review and Meta-Analysis

OBJECTIVE

Prolactin-secreting tumors respond well to medical management, with a few patients requiring surgery. We conducted a systematic review and meta-analysis to study the determinants of surgical remission in these tumors.

METHODS

We searched PubMed to identify eligible studies reporting postoperative remission in patients treated with transsphenoidal surgery for prolactinoma. Primary outcomes included postoperative remission, follow-up remission, and recurrence. Postoperative and follow-up remission were defined as normoprolactinemia at <1 year and >1 year after operation, respectively. Recurrence was defined as hyperprolactinemia after initial normalization of prolactin levels. Odds ratios (ORs) were calculated, stratified by radiologic size, tumor extension, and tumor invasion, and analyzed using a random-effects model meta-analysis.

RESULTS

Thirty-five studies were included. Macroadenomas were associated with lower rates of postoperative remission (OR, 0.20; 95% confidence interval [CI], 0.16-0.24) and lower rates of remission at follow-up (OR, 0.11; 95% CI, 0.053-0.22). Postoperative remission was less likely in tumors with extrasellar or suprasellar extension (OR, 0.16; 95% CI, 0.06-0.43) and tumors with cavernous sinus invasion (OR, 0.03; 95% CI, 0.01-0.13). Female gender and absence of preoperative dopamine agonist treatment were also associated with higher remission rates. Across the included studies, there was considerable heterogeneity in each primary outcome (postoperative remission, I² = 94%; follow-up remission, I² = 86%; recurrence, I² = 68%).

CONCLUSIONS

Transsphenoidal surgery for prolactinomas may be particularly effective in small, noninvasive, treatment-naive tumors and may provide a viable first-line alternative to dopamine agonist therapy in such patients.

Reappraising the Role of Trans-Sphenoidal Surgery in Prolactin-Secreting Pituitary Tumors

Simple Summary

Prolactinomas constitute a subgroup of pituitary adenomas for which there are several treatment options. Dopamine agonists (DA), since their introduction, have shown a strong efficacy both in the control of hyperprolactinemia and of the significant volumetric reduction of prolactinomas, leading, in some cases, to a definitive cure. Trans-sphenoidal surgery (TSS) has been traditionally confined to a failure of medical therapy, pituitary apoplexy with neurological worsening, and prolactinomas with wide cystic components. Moreover, the recent technical innovations introduced in TSS and increasing experience of surgeons have allowed to achieve better results, such as complete tumor resection with lower complication rates. On these grounds, the authors reviewed the extensive institutional Prolactinomas case series over the last 25 years to analyze the role of TSS in the management of Prolactinomas, particularly in terms of the cure rate.

Abstract

Background: Prolactinomas represent a unique challenge for endocrinologists and neurosurgeons. Considering recent innovations in surgical practice, the authors aimed to investigate the best management for prolactinomas. Methods: A retrospective, cross-sectional and monocentric study was designed. Consecutive patients affected by prolactinomas were enrolled if treated with a first-line treatment with a dopamine agonist (DA) or trans-sphenoidal surgery (TSS). Patients carried giant prolactinomas, and those with a follow-up <12 months were excluded. Results: Two hundred and fifty-nine patients were enrolled. The first treatment was DA for 140 patients and TS for 119 cases. One hundred and forty-six of 249 patients (58.6%) needed a second therapy. The mean follow-up was 102.2 months (12–438 months). Surgery highly impacted on the cure rate—in particular, in females (p = 0.0021) and in microprolactinomas (p = 0.0020). Considering the multivariate analysis, the female gender and surgical treatment in the course of the clinical history were the only independent positive predictors of a cure at the end of 5 years follow-up (p = 0.0016, p = 0.0005). The evaluation of serum prolactin (24 hours after TSS) revealed that 86.4% of patients with postoperative prolactin (PRL) ≤10 ng/mL were cured at the end of the follow-up (p < 0.0001). Conclusions: According to our experience, surgery allows a high cure rate of prolactinomas, particularly in females with microadenoma, with a good safety profile. TSS for prolactinomas should be considered as a concrete option, during the multidisciplinary evaluation, in centers of reference for pituitary diseases.

Outcomes of Transsphenoidal Microsurgery for Prolactinomas - A Contemporary Series of 162 Cases

INTRODUCTION

Renewed interest in transsphenoidal surgery (TSS) as a therapeutic option for prolactinomas has emerged. This study is aimed at defining the current role of pituitary surgery in the management of prolactinomas.

MATERIALS AND METHODS

In this retrospective, consecutive single-center study, 162 patients who underwent primary microscopic TSS for prolactinomas between 2006 and 2019 were analyzed regarding surgical indication, previous dopamine-agonist (DA) treatment, early remission rates (3 months postoperatively), surgical complications and pituitary function.

RESULTS

Seventy-four microprolactinomas and 88 macroprolactinomas were operated by TSS. 62.3% of the patients had received prior DA treatment. For microprolactinomas, the predominant indication for surgery was patient's wish (41.9%), while indications for macroprolactinomas varied. For enclosed microprolactinomas, the initial remission rate was 92.1%, while for macroprolactinomas, the rate was 70.4%. No significant difference of remission rates was found between DA-pretreated (65.3%) and non-pretreated (72.1%) patients (p=0.373).None of the patients suffered a significant complication. Re-operation for a postoperative cerebrospinal fluid leak was required in one patient (0.6%). Permanent postoperative deterioration of pituitary function was only observed in one of 158 patients with surgery for a prolactinoma (0.6%). Improvement of pituitary function was observed in 8 of 25 patients (32%) with preoperative deficits.

CONCLUSION

Transsphenoidal microsurgery is safe and efficient for treatment of prolactinomas. It is particularly suitable for enclosed prolactinomas. The patient should be well informed of the pros and cons of the treatment options, which include DA medication and TSS, and the patient's preference should be taken into account during decision-making.

Surgery and Medical Treatment in Microprolactinoma: A Systematic Review and Meta-Analysis

OBJECTIVE

Dopamine agonists (DAs) are recommended as the first-line treatment for prolactinomas; however, tumour recurrence after drug withdrawal remains a clinical problem. Recent studies have reported high remission rates via surgery in microprolactinomas. The aim of this systematic review and meta-analysis was to compare the clinical result of DA treatment with surgery as initial therapy in patients with treatment-naive microprolactinoma.

METHODS

A comprehensive literature search for studies and reports regarding microprolactinoma patients treated with DAs and/or surgery published between January 1970 and November 2020 was conducted using four electronic databases (PubMed, Embase, Google Scholar, and the Cochrane Library). Clinical treatment outcome was evaluated by the biochemical remission of serum prolactin level to normal after treatment. The I ² statistic was used to quantify heterogeneity. Pooled data were analysed according to a random effect model.

RESULTS

Eighteen studies with 661 patients were included for analysis. The DA treatment group achieved a higher remission rate at ≥12 months follow-up (96% vs. 86%; P=0.019). Surgery showed a higher remission rate than the DA treatment group after the treatment withdrawal (78% vs. 44%; P=0.003). Patients with preoperative prolactin level of ≤200 ng/mL had a higher remission rate than patients with preoperative prolactin level of >200 ng/mL (92% vs. 40%; P=0.029).

CONCLUSION

Surgery showed a high remission rate in treatment-naive microprolactinoma patients after treatment withdrawal and may be an alternative first-line treatment strategy in addition to DAs, particularly in patients with a preoperative prolactin level of ≤200 ng/mL.

Surgery for prolactinomas: a better choice?

PURPOSE

Renewed interest in transsphenoidal surgery (TSS) as a therapeutic option for prolactinomas has emerged.

METHODS

Based on contemporary literature and own experience, the changing role of surgery for treatment of prolactinomas is discussed.

RESULTS

Today, TSS is performed by minimally invasive microscopic or endoscopic techniques. Normoprolactinemia is obtained in 71-100% of patients with microprolactinomas by TSS. Almost equal results are found in circumscribed intrasellar macroprolactinomas. In experienced hands, pituitary function is preserved in TSS. The risk of cardiac valve disease is still a concern with ergot-derived dopamine-agonists (DAs) in patients requiring long-term, high-dose dopamine-agonist (DA) treatment. Cost-utility analysis favors TSS over DA treatment. The possible negative impact of DA treatment on future surgical results is still a controversial and unsettled issue. In patients who wish to become pregnant, the advantages of microprolactinoma removal to avoid DAs and macroprolactinoma debulking to avoid symptomatic enlargement during pregnancy should be discussed with the patients. Young patients' age is an argument for surgery to circumvent the unpredictable sequelae of long-term DA treatment. Surgery should be discussed in male gender because of a higher likelihood of DA resistance and aggressive behavior of prolactinoma.

CONCLUSION

Given excellent results of TSS and concerns about medical treatment, the scale of indications for TSS as an alternative to DAs has increased. The patient's wishes concerning a chance at a cure with TSS instead of a long-term treatment with DAs has become an important and accepted indication. With DA medication and TSS, two effective treatment modalities for prolactinomas are available that can be used in a complementary fashion.

Ubenimex induces apoptotic and autophagic cell death in rat GH3 and MMQ cells through the ROS/ERK pathway

Purpose

Ubenimex, an aminopeptidase N (APN) inhibitor, is widely known for its use as an adjunct therapy for cancer therapy. However, in recent studies, it has also conferred antitumour effects in many cancers, but its anticancer mechanism is largely unknown. This study aims to investigate the specific anticancer activities and mechanisms of ubenimex in GH3 and MMQ cells.

Materials and methods

In this study, we investigated the anticancer effects of ubenimex in GH3 and MMQ cells. Cell viability and cell death were assessed by the Cell Counting Kit-8 kit (CCK-8) and a LIVE/DEAD cell imaging kit. Apoptosis and intracellular reactive oxygen species (ROS) generation were assessed by flow cytometry and fluorescence microscopy. Autophagosome formation was detected by transmission electron microscopy, and autophagic flux was measured with mRFP-GFP-LC3 adenoviral transfection. The protein expression level was detected by Western blotting.

Results

The results revealed that treatment with ubenimex induced apoptotic and autophagic cell death in GH3 and MMQ cells, which resulted in decreased viability, an increased proportion of apoptotic cells, and autophagosome formation. Further experiments showed that ubenimex induced ROS generation and activated the ROS/ERK pathway. The ROS scavenger NAC could attenuate ubenimex-induced apoptosis and autophagy.

Conclusion

Our studies revealed that ubenimex exerted anticancer effects by inducing apoptotic and autophagic cell death in GH3 and MMQ cells, rendering it a possible effective adjunctive therapy for pituitary treatment.

The epidemiology, diagnosis and treatment of Prolactinomas: The old and the new

Prevalence and incidence of prolactinomas are approximately 50 per 100,000 and 3-5 new cases/100,000/year. The pathophysiological mechanism of hyperprolactinemia-induced gonadotropic failure involves kisspeptin neurons. Prolactinomas in males are larger, more invasive and less sensitive to dopamine agonists (DAs). Macroprolactin, responsible for pseudohyperprolactinemia is a frequent pitfall of prolactin assay. DAs still represent the primary therapy for most prolactinomas, but neurosurgery has regained interest, due to progress in surgical techniques and a high success rate in microprolactinoma, as well as to some underestimated side effects of long-term DA treatment, such as impulse control disorders or impaired quality of life. Recent data show that the suspected effects of DAs on cardiac valves in patients with prolactinomas are reassuring. Finally, temozolomide has emerged as a valuable treatment for rare cases of aggressive and malignant prolactinomas that do not respond to all other conventional treatments.

Surgery for Prolactinomas to Date

While in the past surgery for prolactinomas was a competitive option to medical treatment with dopamine agonists, to date the indications for operations are restricted to only a few specific situations. However, if a patient is intolerant to medical treatment or if the drugs are not sufficiently effective in terms of lowering prolactin levels or tumor shrinkage, surgery should always be considered. In microprolactinomas, operations can achieve excellent prolactin normalization rates. In tumors difficult to treat, the combination of surgical tumor resection and long-term medical treatment supports better control of the disease. The individual indications, results, techniques, and complications of operations for prolactinomas are briefly reviewed in this paper.

The experience with transsphenoidal surgery and its importance to outcomes

PURPOSE

Surgical experience is considered paramount for excellent outcome of transsphenoidal surgery (TSS). However, objective data demonstrating the surgical success in relation to the experience of pituitary surgery units or individual experience of pituitary surgeons is sparse.

METHODS

Based on literature data, we have investigated the influence of experience with TSS for pituitary adenomas on endocrinological remission rates and on operative complications. The surgical experience was assessed by calculating the number of transsphenoidal operations per year.

RESULTS

For TSS of microprolactinomas, mean remission rates were 77% in centers with < 2 operations per year for microprolactinomas, 82% with 2-4 operations, 84% with 4-6 operations, and 91% with > 6 operations. A yearly experience with more than 10 initial operations for Cushing's disease (CD) warrants a remission rate exceeding 70%. Remission rates in CD exceeding 86% have only been reported for single surgeon series. Extraordinarily high complication rates were found in some series with < 25 yearly total operations for pituitary adenomas. Major vascular complications were less than 2% and revision rates for rhinorrhea usually < 2.5% in centers performing > 25 transsphenoidal operations per year.

CONCLUSIONS

We conclude that a center with experience of > 25 transsphenoidal operations for pituitary adenomas per year provides a high likelihood of safe TSS. Surgery for CD requires a particularly high level of practice to guarantee excellent remission rates. The endocrinologist has the unique opportunity to audit the surgical success by hormone measurement and to refer patients to neurosurgeons with proven excellence.

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.

[Indications for surgical treatment of prolactin-secreting pituitary adenomas]

Prolactinomas account for about 40% of all pituitary adenomas. The main treatment for prolactinomas is undoubtedly therapy with dopamine agonists (DAs). However, prolonged conservative treatment (for many years or even throughout life) that is necessary for permanent control of the disease makes some patients refuse pharmacological treatment for various reasons. In addition, not all prolactinomas respond to DAs therapy. Sometimes, the patient is not able to continue treatment because of the severity of side effects. Along with tumor resistance to therapy and patient intolerance of DAs, complications (liquorrhea, hemorrhage in the tumor) may occur during conservative treatment. In these cases, surgery is necessary. The paper analyzes the modern literature on various treatment options for prolactin-secreting pituitary adenomas and defines the indications for surgical treatment.

THERAPY OF ENDOCRINE DISEASE: Surgery in microprolactinomas: effectiveness and risks based on contemporary literature

Microprolactinomas are the most common pituitary adenomas. In symptomatic patients, dopamine agonists are the first-line treatment of choice; when cabergoline is used, biochemical control rates between 85 and 93% have been reported. Long-term treatment is needed in most of the cases with compliance, patient convenience, and potential adverse effects representing areas requiring attention. Based on the literature published in the past 15 years, transsphenoidal surgery can lead to normal prolactin in the postoperative period in usually 71-100% of the cases with very low postoperative complication rates. Surgical expertise is the major determinant of the outcomes, and it may be a cost-effective option in young patients with life expectancy greater than 10 years (provided it is performed by experienced surgeons at high volume centers with confirmed optimal outcomes). Larger series of patients with adequate follow-up could further validate the place of transsphenoidal surgery (particularly through the endoscopic approach for which long-term results are currently limited) in the management algorithm of patients with microprolactinoma.

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.

Surgical treatment of microprolactinomas: pros

Medical therapy with dopaminergic agonists (DAs) has been used for several decades for the treatment of both micro- and macroprolactinomas, without much differentiation between the two conditions. While most cases respond well to DAs in terms of prolactin normalization and control of tumor growth, DAs are often needed for many years, or even for lifetime. Concerns have been raised recently about the possible side effects of long-term use of these medications on the anatomy and function of the heart valves. While macroprolactinomas are rarely surgically curable, pituitary surgery in expert hands is a safe and effective method to permanently cure microprolactinomas, with long-term cure rates around 70 %. In this article, I will review the data on safety of DAs an on the effectiveness and safety of surgery, and I will make an argument that surgery should be offered as a possible therapy to microprolactinoma patients, provided that an experienced pituitary neurosurgeon is available.

Results of immunohistochemical staining of cell-cycle regulators: the prediction of recurrence of functioning pituitary adenoma

OBJECTIVE

This study was undertaken primarily to investigate the possible prognostic values of several cell-cycle regulators for the prediction of functioning pituitary adenoma (FPA) recurrence after surgical resection by immunohistochemically analyzing tumor samples obtained by surgical resection.

METHODS

The medical records of the patients with FPA diagnosed from January 2000 to December 2009 at the Department of Neurosurgery at Samsung Changwon Hospital and Dong-A University Medical Center were selected. Immunohistochemical staining was performed on archived paraffin-embedded tissues obtained by surgical resection for adenohypophysial cells, cell-cycle regulatory proteins (p16, p15, p21, cyclin-dependent kinase [CDK] 4 and 6, phosphorylated retinoblastoma [pRB] protein, and cyclin D1), MIB-1 antigen, and p53.

RESULTS

Of the 174 FPAs, 62 (35.6%) recurred during follow-up period (mean duration 62.4 months, range 24.2-118.9 months). Immunohistochemically, overstaining for p16 in 89 samples (51.1%), p15 in 27 samples (15.5%), p21 in 20 samples (11.5%), CDK4 in 54 samples (31.0%), CDK6 in 18 samples (10.3%), pRB protein in 69 samples (39.7%), and cyclin D1 in 87 samples (50.0%). Multivariate analysis using the Cox proportional hazard regression model showed that invasion into cavernous sinus (hazard ratio [HR] of 4.02; P < 0.001), immunohistochemical normostaining for p16 (HR of 3.16; P < 0.001), immunohistochemical overstaining for pRB protein (HR of 2.45; P = 0.008), cyclin D1 (HR of 2.13; P = 0.029), MIB-1 antigen (HR of 2.74; P = 0.002), and p53 (HR of 2.21; P = 0.002), predicted the recurrence of FPA after surgical resection.

CONCLUSIONS

Our findings indicate that p16, pRB protein, and cyclin D1 are associated with recurrence FPA after surgical resection.