Pituitary Neuroendocrine Tumors Research Articles

Simultaneous combined keyhole mini-transcranial approach and endoscopic transsphenoidal approach to remove multi-lobulated pituitary neuroendocrine tumor with suprasellar extension

BackgroundTranssphenoidal surgery (TSS) is the main method to remove pituitary neuroendocrine tumor (PitNET), but large or multi-lobulated one is still challenging. ObjectiveThe less invasive simultaneous combined keyhole mini-transcranial approach and standard transsphenoidal approach was used to remove multi-lobulated or hourglass-shaped non-functioning PitNET to avoid the specific complications related to extended TSS. MethodsTwenty-one patients of large multi-lobulated or hourglass-shaped PitNET (6 patients were recurrent cases after TSS or transcranial approach) were treated by this simultaneous combined approach. The supraorbital or midline keyhole approach was performed under the operating microscope so that the fine arteries feeding optic apparatus were dissected from the tumor capsule safely and securely and the suprasellar part of the tumor was removed in the extra-capsular fashion in combination with transsphenoidal approach. ResultsVisual function improved after the surgery in 14 (74 %) of 19 patients with preoperative disturbance of the visual fields. Four patients (19 %) developed postoperative deterioration of pituitary endocrine functions requiring permanent hormonal replacement. One patient (4.2 %) suffered cortical laminar necrosis without permanent disorders and another patient (4.2 %) suffered cerebrospinal fluid rhinorrhea but neither was permanent. Postoperative computed tomography detected no subarachnoid hemorrhage in any patient. Gross total removal was achieved in 15 patients (71 %). Five patients (24 %) with subtotal removal and one patient (4.2 %) with partial removal had lateral tumor extension with Knosp classification 3 or 4. ConclusionThe combined method is an effective treatment option to remove complex PitNET safely and securely with dissecting fine arteries on the tumor capsule.

Unlocking the Genetic Secrets of Acromegaly: Exploring the Role of Genetics in a Rare Disorder.

Acromegaly is a rare endocrine disorder characterized by the excessive production of growth hormone (GH) in adulthood. Currently, it is understood that certain pituitary neuroendocrine tumors (PitNETs) exhibit a hereditary predisposition. These tumors' genetic patterns fall into two categories: isolated and syndromic tumors. The isolated forms are characterized by molecular defects that predispose exclusively to PitNETs, including familial isolated pituitary adenomas (FIPAs) and sporadic genetic defects not characterized by hereditary predisposition. All the categories involve either germline or somatic mutations, or both, each associated with varying levels of penetrance and different phenotypes. This highlights the importance of genetic testing and the need for a more comprehensive view of the whole disease. Despite the availability of multiple treatment options, diagnosis often occurs after several years, and management is still difficult. Early detection and intervention are crucial for preventing complications and enhancing the quality of life for affected individuals. This review aims to elucidate the molecular, clinical, and histological characteristics of GH-secreting PitNETs, providing insights into their prevalence, treatment nuances, and the benefits of genetic testing for each type of genetic disorder associated with acromegaly.

Suprasellar Anterior-Posterior Diameter Optimizes the Use of Intraoperative MRI in Patients Undergoing Endoscopic Pituitary Surgery.

Intraoperative MRI (iMRI) has been demonstrated to improve the extent of resection of pituitary neuroendocrine tumors resected using endoscopic endonasal approaches. We sought to establish if preoperative clinicoradiological parameters could be used to predict which patients are most likely to benefit from iMRI and thus allow more efficient use of this technology. A prospectively maintained surgical database of all endoscopic pituitary tumor resections with iMRI guidance performed between May 2017 and September 2023 was accessed. Data were collected on clinical and radiological parameters that may predict reintervention after iMRI. Logistic regression models were constructed to assess the relationship between predictor variables and reintervention after iMRI. Seventy-three patients were included in the study. After review of the iMRI, 24/73 (33%) patients underwent surgical reintervention. The combined rate of gross total resection/near total resection was 64/73 (88%). The rate of biochemical cure of endocrine disease after surgery for a hormonally active tumor was 15/21 (71%). On univariate logistic regression analysis, the only factor significantly associated with reintervention after iMRI was the suprasellar anterior-posterior diameter (odds ratio 1.1, 95% CI 1.01-1.2, P = .030). Suprasellar anterior-posterior diameter ≥15 mm predicts the requirement for reintervention after endoscopic resection of pituitary neuroendocrine tumor. Use of this easily obtained radiological parameter will allow iMRI to be used in those patients who are most likely to benefit.

Differential proteomic expression in non-functional pituitary neuroendocrine tumours and pituitary glands.

Pituitary neuroendocrine tumours (PitNETs) are common accounting for 10 to 25 % of all intracranial tumours. This project describes the feasibility of developing a novel membrane-based biomarker that could be used for fluorescent guided surgery. The aim was to catalogue the differential expression of membrane proteins between non-functional PitNETs and pituitary glands. Ten pituitary gland tissue specimens were obtained from the National Institute of Health (NIH) NeuroBio-Bank and twenty non-functional PitNETs were obtained from the Northwestern University Nervous System Tumour Bank. Mass spectrometry analysis using an Orbitrap Fusion Lumos Tribrid Mass Spectrometer linked to a Dionex Ultimate 3000 UPLC system was undertaken. Data Dependent Acquisition Mass Spectrometry and Data Independent Acquisition Mass Spectrometry was then completed. Pathway enrichment analysis was performed using clusterProfiler v4.6.0. Functional enrichment analysis was conducted using Gene Ontology terms and Reactome pathways. Differential expression analysis between the two groups revealed a total of 2110 significant differently expressed proteins (DEPs), with 1387 of these also having a Log2 fold change either greater than 1, or less than -1. Of the 2110 DEPs, 925 were upregulated in tumours compared to control, while 1185 were downregulated. We have demonstrated a proteomic comparison between non-functional PitNETs and normal pituitary glands. These results demonstrate differences consistent with contemporary literature but shows that NOTCH3 and PTPRJ are up-regulated in non-functional PitNETs compared to pituitary glands.

Clinical observation of 7 cases of functional pituitary neuroendocrine tumor treated by endoscopic transnasal selective resection of the cavernous sinus medial wall

The clinical data of 7 patients (3 males and 4 females) with functional pituitary neuroendocrine tumor treated by endoscopic transnasal resection of the cavernous sinus medial wall from May to October 2023 in the Department of Neurosurgery of the First Affiliated Hospital of University of Science and Technology of China were retrospectively analyzed. They ranged in age from 29 to 60, with an average age of 45. The clinical diagnosis was acromegaly in 5 cases and Cushing's disease in 2 cases. There were 1 cases of microadenoma and 6 cases of macroadenoma. Knosp grade: Grade 1 adenoma in 3 cases, grade 2 adenoma in 3 cases and grade 3A adenoma in 1 case. Intraoperative resection of cavernous sinus medial wall was performed on the side of tumor. Five cases were determined to be invaded by tumor, and 2 cases were uncertain. No internal carotid artery injury occurred in all patients. The average intraoperative blood loss was 156 ml, and no patient was transfused. Postoperative endocrine remission was found in 6 cases, and tumor cells were found in 6 cases by pathological examination of the medial wall of cavernous sinus. No serious complications occurred in all patients. For Knosp grade 1-3 functional pituitary neuroendocrine tumor surgery, if there is no clear false envelope or normal pituitary between the tumor and the cavernous sinus medial wall during the operation, the cavernous sinus medial wall should be actively removed to improve the postoperative endocrine remission rate.

Collision of pituitary neuroendocrine tumor and anterior clinoid meningioma treated with a two-stage minimally invasive surgical strategy: illustrative case.

The locations of pituitary neuroendocrine tumor (PitNET) and anterior clinoid meningioma (ACM) appear to be very close but essentially different, as the former is inside the sella turcica while the latter is in the intradural space. A collision tumor thus requires a specific treatment strategy but has been rarely reported. A 77-year-old woman presented with progressive visual impairment due to significant compression of the optic apparatus by a collision of PitNET and ACM. With a minimally invasive two-stage therapeutic strategy, the ACM was first resected using an endoscopic mini-pterional approach, then the PitNET was removed with an endoscopic transnasal approach 8 weeks later, leading to significant improvement in visual function. The authors' literature search identified only 2 documented cases of a similar collision. This case underscores the complexity of the decision-making process in the management of collision tumors and suggests the potential benefit of staged minimally invasive surgical interventions in preserving visual function. Further accumulation of cases is warranted for refining the treatment strategy. https://thejns.org/doi/10.3171/CASE24240.

Distinguishing Pituitary Metastasis and Pituitary Neuroendocrine Tumors through Conventional MR Imaging and Clinical Features.

Given their overlapping features, pituitary metastases frequently imitate pituitary neuroendocrine tumors in neuroimaging studies. This study aimed to distinguish pituitary metastases from pituitary neuroendocrine tumors on the basis of conventional MR imaging and clinical features as a practical approach. In this 2-center retrospective study, backward from January 2024, preoperative pituitary MR imaging examinations of 22 pituitary metastases and 74 pituitary neuroendocrine tumors were analyzed. Exclusion criteria were as follows: absence of a definitive histopathologic diagnosis, history of pituitary surgery or radiation therapy before MR imaging, and pituitary neuroendocrine tumors treated with medical therapy. Two radiologists systematically evaluated 13 conventional MR imaging features that have been reported more commonly as indicative of pituitary metastases and pituitary neuroendocrine tumors in the literature. Age, sex, history of cancer, and maximum tumor size constituted the clinical/epidemiologic features. The primary cancer origin for this study was also noted. Univariable and multivariable logistic regression was used for the selection of variables, determining independent predictors, and modeling. Interobserver agreement was evaluated for all imaging parameters using the Cohen κ statistic or intraclass correlation coefficient. A total of 22 patients with pituitary metastases (8 women; mean age, 49.5 [SD, 13] years) and 74 patients with pituitary neuroendocrine tumors (36 women; mean age, 50.1 [SD, 11] years) were enrolled. There was no statistically significant distributional difference in age, sex, or maximum tumor size between the 2 groups. Lung cancer (9/22; 41%) was the most commonly reported primary tumor, followed by breast (3/22; 13.6%) and unknown cancer (3/22; 13.6%). Logistic regression revealed 3 independent predictors: rapid growth on control MR imaging, masslike or nodular expansion of the pituitary stalk, and a history of cancer. The model based on these 3 features achieved an area under the curve, accuracy, sensitivity, specificity, and Brier score of 0.987 (95% CI, 0.964-1), 97.9% (95% CI, 92.7%-99.8%), 95.5% (95% CI, 77.2%-99.9%), 98.6% (95% CI, 92.7%-100%), and 0.025, respectively. Two conventional features based on pituitary MR imaging with the clinical variable of history of cancer had satisfying predictive performance, making them potential discriminators between pituitary metastases and pituitary neuroendocrine tumors. In cases in which differentiation between pituitary metastases and pituitary neuroendocrine tumors poses a challenge, the results of this study may help with the diagnosis.

The Relationship Between Race, Social Vulnerability Index, and Clinical Follow-Up After Surgical Resection of Pituitary Tumors

IntroductionSocioeconomic status and race have been found to influence patient outcomes for various cancer subtypes. In particular, minority and economically vulnerable patients present with more advanced disease and experience decreased survival compared to others. The aim of this study was to analyze the association between demographic or socioeconomic variables and rates of post-surgical follow-up after pituitary neuroendocrine tumor (PitNET) resection. MethodsA retrospective review was completed for patients with PitNETs who underwent surgery between 2018-2021. Patient demographics and information related to post-operative appointments and MRIs were obtained. Social vulnerability index (SVI) scores were recorded from the Centers for Disease Control based on nationwide census tracts. ResultsOne-hundred and sixteen patients were included in the analysis (57 males). In this cohort, 50% were Black, 34% Hispanic, 9% White, and 1% Asian. Mean overall SVI score was 0.81±0.23. The mean number of cancelled appointments was significantly higher in the moderate-high/high SVI group (p=0.034). Additionally, 30% of patients with moderate-high/high SVI had ≥2 cancelled follow-up visits compared to 0% among patients with low/low-moderate SVI (p=0.035). On average, White patients were less likely than non-White patients to have at least one cancelled follow-up appointment (p=0.048). ConclusionBlack patients and those with high social vulnerability have decreased rates of follow-up after PitNET resection. Follow-up delays can lead to failed identification of tumor recurrence, potentially resulting in more advanced disease by the time medical care is re-initiated and increasing rates of patient morbidity and mortality. As a result, further work is needed to address and bridge these care gaps.

Anatomical Differences in Sphenoid Sinus During Endoscopic Transsphenoidal Surgery: Comparison Between Nonfunctioning Pituitary Neuroendocrine Tumor (PiTNET) and Growth Hormone-Secreting PiTNET

In surgical practice during endoscopic endonasal approach, growth hormone-secreting pituitary neuroendocrine tumor (GH-secreting PitNET) patients show morphologic differences in the nasal cavities and sinuses, leading to a narrower surgical field and a carotid prominence and potentially increasing the complexity of the surgical and the risk of complications. The aim of the study is to evaluate the anatomical differences of the sphenoid sinus between patients with GH-secreting PitNETs and patients with nonfunctioning pituitary neuroendocrine tumor (NF-PitNET) who underwent endoscopic endonasal approach. This is a monocentric retrospective study conducted at the author's institution. The minimum intercarotid distance, the largest diameter of the sphenoid sinus (DSS), and the distance between vomer and clivus (VCD) were collected and compared. Presence, localization, and course of intersphenoid sinus septum were also evaluated. One hundred consecutive patients were identified: 57 males (57%) and 43 females (43%), with a mean age of 55years. Sixty patients had NF-PitNET (60%) and 40 had GH-secreting PitNET (40%). GH-secreting PitNET group presented inferior values of intercarotid distance (16.8 ± 3.94mm vs. 20.4 ± 3.94mm, P < 0.001), DSS (32.5 ± 9.81mm vs. 38.6 ± 11.03mm, P= 0.006), and VCD (25.5 ± 6.96mm vs. 29.6 ± 8.47mm, P= 0.012) compared to NF-PitNET group. Intersphenoid sinus septum showed no differences between the 2 groups. Intercarotid distance, DSS, and VCD resulted smaller in acromegalic patients, confirming that patients with GH-secreting PitNETs have a narrower surgical field. A meticulous anatomical preoperative planning and neuronavigation are important to recognize the sphenoid anatomical landmarks in order to reduce the risk of complications, especially in acromegalic patients.

Identifying prognostic predictors for postoperative pituitary neuroendocrine tumour recurrence: an integrated clinical, radiological, and immunohistochemistry assessment

Objective Pituitary neuroendocrine tumours (PitNETs) are the second most common type of intracranial tumour. Several studies have explored the prognostic factors for PitNETs. However, prognostic factors for postoperative PitNET recurrence remain not fully understood. This study aimed to explore potential prognostic factors for PitNET recurrence, such as surrounding tissue invasion and the extent of surgical resection in patients with postoperative PitNETs. Methods We included 106 patients who underwent PitNET surgery between 2013 and 2018, dividing them into two groups: those with recurrence and those without recurrence. Tumours were classified based on demographics, neuroradiological, and immunohistological characteristics. Univariate and multivariate analyses were used to determine factors predicting recurrence. Kaplan–Meier plots and log-rank tests were used to analyse each independent factor based on the cumulative 5-year recurrence rate. Results During the 5-year follow-up period, 29.2% of the patients (n = 31) had disease recurrence. Univariate analysis showed that predictors of recurrence included cavernous and sphenoid sinus invasions, optic chiasm compression, larger tumour volume, giant adenoma >4 cm, and gross total resection (GTR). Multivariate analysis showed that lactotroph tumour type, sphenoid sinus invasion, and GTR were independent predictors. Kaplan–Meier analysis revealed significant differences in the 5-year recurrence rate among the three independent predictors, with significantly lower recurrence rate in patients with lactotroph tumours and GTR, and a significantly higher recurrence risk in patients with sphenoid sinus invasion. Conclusions Lactotroph tumour type, sphenoid sinus invasion, and GTR are independent predictors of postoperative PitNET recurrence. This study provides insights into the factors affecting postoperative PitNET recurrence.

DPPA4 increases aggressiveness of pituitary neuroendocrine tumors by enhancing cell stemness.

Pituitary neuroendocrine tumors, PitNETs, are often aggressive and precipitate in distant metastases that are refractory to current therapies. However, the molecular mechanism in PitNETs' aggressiveness is not well understood. Developmental pluripotency-associated 4 (DPPA4) is known as a stem cell regulatory gene and overexpressed in certain cancers, but its function in the context of PitNETs' aggressiveness is not known. We employed both rat and human models of PitNETs. In the rat pituitary tumor model (RPT), we used prenatal-alcohol-exposed (PAE) female Fischer rats which developed aggressive PitNETs following estrogen treatment, while in the human pituitary tumor (HPT) model, we used aggressively proliferative cells from pituitary tumors of patients undergone surgery. Various molecular, cellular, and epigenetic techniques were used to determine the role of DPPA4 in PitNETs' aggressiveness. We show that DPPA4 is overexpressed in association with increased cell stemness factors in aggressive PitNETs of PAE rats and of human patients. Gene-editing experiments demonstrate that DPPA4 increases the expression of cell stemness and tumor aggressiveness genes and promotes proliferation, colonization, migration, and tumorigenic potential of PitNET cells. ChIP assays and receptor antagonism studies reveal that DPPA4 binds to canonical WINTs promoters and increases directly or indirectly the Wnt/β-catenin control of cell stemness, tumor growth, and aggressiveness of PitNETs. Epigenetic studies show involvement of histone methyltransferase in alcohol activation of DPPA4. These findings support a role of DPPA4 in tumor stemness and aggressiveness and provide a preclinical rationale for modulating this stemness regulator for the treatment of PitNETs.

Pseudocapsular resection to prevent recurrence in nonfunctioning pituitary neuroendocrine tumors: a retrospective, single-center study with more than 5 years of follow-up.

Pseudocapsular resection is a well-recognized, useful approach to achieve endocrinological remission in functioning pituitary neuroendocrine tumors (PitNETs). However, its advantage in nonfunctioning PitNETs (NF-PitNETs) has not been established. This study aimed to clarify the contribution of pseudocapsular resection to the prevention of NF-PitNET recurrence in long-term follow-up. This retrospective study included 132 patients who underwent total tumor removal and were followed for more than 5 years after surgery. The patients were categorized into those who underwent total pseudocapsular resection (n = 67) and those who did not (n = 65). The nonpseudocapsule (nonpseudocap) resection group included patients who underwent partial pseudocapsular resection and those in whom the pseudocapsule was not resected, did not exist, or could not be identified during surgery. The main outcome measures were the tumor recurrence rate and site of recurrence. In the nonpseudocap resection group, 2 patients (3.1%) had tumor recurrence in the cavernous sinus and 5 (7.7%) had tumor recurrence in the pituitary fossa. In the pseudocapsule (pseudocap) resection group, only 2 patients (3.0%) had tumor recurrence in the cavernous sinus and 0 patients had tumor recurrence in the pituitary fossa. Tumor recurrence in the pituitary fossa was more likely to occur in the nonpseudocap resection group than in the pseudocap resection group (p = 0.0267). Multivariate regression analysis revealed that pseudocapsular resection was a significant factor for reducing the tumor recurrence rate in the pituitary fossa (p = 0.0107). Pseudocapsular resection may reduce the rate of tumor recurrence and improve the management of NF-PitNETs in long-term follow-up.

Silent Corticotroph Adenomas Demonstrate Predilection for Sphenoid Sinus, Cavernous Sinus, and Clival Invasion Compared with Other Subtypes

Nonfunctional pituitary neuroendocrine tumors (PitNETs) exhibit wide variability in growth pattern based on subtype. Silent corticotroph adenomas (SCAs) demonstrate aggressive growth compared with other nonfunctional pituitary adenomas (NFPAs), especially into the cavernous sinus. In this study, we sought to characterize other growth patterns of SCAs compared with NFPAs. We performed a retrospective analysis of all patients with nonfunctional PitNETs treated with surgical resection via endoscopic endonasal approach at a single institution from August 1, 2018, to May 11, 2024. Preoperative computed tomography and magnetic resonance imaging were reviewed to determine extension into the suprasellar space, sphenoid sinus, cavernous sinus, and clivus. The study comprised 91 patients, including 20 SCAs and 71 NFPAs. SCAs demonstrated significantly greater rates of growth into the sphenoid sinus (55.0% vs. 23.94%, P= 0.013), clivus (65.0% vs. 16.9%, P < 0.0001), and cavernous sinus (defined as Knosp grade 3 or 4; 55.0% vs. 23.35%, P= 0.016). Other NFPAs were more likely to grow into the suprasellar space (92.96% vs. 75.0%, P= 0.038). Tumor volume was similar between groups (11.93 cm3 vs. 9.06 cm3, P= 0.2). Silent corticotroph PitNETs demonstrate predilection for invasion of bony structures, with higher rates of growing through the sellar floor into the sphenoid sinus, growing posteroinferiorly into the clivus and laterally into the cavernous sinuses. Other nonfunctional PitNETs tended to follow the path of least resistance, growing superiorly into the suprasellar space. These differences in growth patterns may account for some of the clinical challenges of treating silent corticotroph PitNETs.

AB092. Imaging the histopathology subtypes of the growth hormone-secreting pituitary neuroendocrine tumor.

Sparsely granulated (SG) growth hormone-secreting pituitary neuroendocrine tumors (GH-PitNETs) often present with a more aggressive clinical course compared to densely granulated (DG) tumors. These subtypes exhibit distinct biological and imaging characteristics. Thus, this study aims to differentiate between the histopathological subtypes of GH-PitNETs using pre-operative magnetic resonance imaging (MRI). A retrospective analysis was conducted on 83 acromegalic patients treated at our institution between 2000 and 2010. Tumor volumes were segmented from preoperative MRIs, including T1-weighted, T2-weighted, T1 with contrast, and T2 fluid attenuated inversion recovery (FLAIR) sequences. Reference regions of interest (ROIs) were delineated using gray and white matter from the same sequences. Two pathologists reviewed pathology specimens for anti-cytokeratin (CAM 5.2) and Pit-1 expression. Clinical and radiological biomarkers were compared between SG and DG patients. A total of 83 patients with complete histopathology and 51 patients with complete MRIs were included in the analysis. SG PitNETs exhibited higher rates of supra-sellar invasion (61.5%, P<0.001), larger tumor sizes, lower pre-operative GH levels, and increased post-operative residual tumor (65.4%, P<0.001) compared to DG PitNETs. Additionally, SG PitNETs showed greater hyperintensity on T2-weighted images and enhanced contrast, whereas DG PitNETs exhibited less contrast enhancement. Utilization of these imaging biomarkers demonstrated an 94.1% accuracy in T2 FLAIR and overall of 78.7% predicting the histopathological subtypes of GH-PitNETs. Distinct histopathological subtypes of GH-PitNETs represent crucial prognostic factors. Utilizing multimodal pre-operative MRIs, clinicians can accurately identify sparsely granulated GH-PitNETs, facilitating improved treatment planning strategies.

Outcome of endoscopic transsphenoidal surgery for acromegaly: Comparison of using and not using the floor standing pneumatic powered endoscope-holder system

IntroductionEndoscopic transsphenoidal surgery can be performed by two surgeons, including an endoscopist (PE/2S), and by a single surgeon with an endoscope-holder system (PE/1S + H). We analyzed the surgical outcome, and outcome predictors in acromegaly patients in endoscopic transsphenoidal surgery using floor standing pneumatic endoscope-holder system. MethodsEndoscopic transsphenoidal surgery was performed with PE/1S+H (n = 51) and PE/2S (n = 20). Postoperative remission was evaluated by the 2010 consensus criteria for acromegaly. We compared the surgical results of PE/2S style and PE/1S+H style, and investigated the factors associated with favorable surgical outcomes. ResultsThere was no difference in clinical background between the PE/2S and the PE/1S + H groups. The remission rates for PE/2S and PE/1S+H were 65.0% and 82.4%, respectively, with no significant difference (p = 0.128). In consecutive 71 cases, statistically useful predictors of remission were low preoperative growth hormone (GH) level (<12 ng/mL), low Knosp grade (0–2), and low revised Knosp grade (0–3A). In the conventional Knosp grade 0–2 and 3/4, the sensitivity was 0.76 and the specificity was 0.81. In the revised Knosp grade 0–3A and 3B/4, the sensitivity was 0.96 and the specificity was 0.44. ConclusionThe outcome of GH-producing pituitary neuroendocrine tumors surgically removed by PE/1S+H could be almost equivalent to that by PE/2S. Preoperative low GH level and Knosp grades, including revised Knosp grades, are useful preoperative predictors for surgical remission of acromegaly.

No unfavorable effects on the menstruation recovery of early postoperative hypoprolactinemia after transsphenoidal surgery in patients with lactotroph pituitary neuroendocrine tumor

ObjectiveTranssphenoidal surgery for lactotroph pituitary neuroendocrine tumor (PitNET) lowers serum prolactin concentrations, occasionally below the normal range. However, the clinical significance of postoperative hypoprolactinemia is still unclear. In this study, we retrospectively reviewed the female patients with lactotroph PitNET who were treated with transsphenoidal surgery to elucidate the influence of postoperative hypoprolactinemia on regular menstruation restoration and endocrinological remission.ResultsThe serum prolactin levels in all thirty three participating females had decreased following surgery. Serum prolactin levels in seven patients had decreased below the lower limit of normal ranges (hypoproactinemia group) and in the remaining twenty six patients, it was within the normal range (non-hypoproractinemia group). In hypoprolactinemia group, regular menstruation was restored in all patients with only lactotroph axis deficiency. Nine patients from the non-hypoprolactinemia group experienced re-elevation of serum prolactin concentration (27%). No patient in hypoprolactinemia group experienced the relapse of hyperprolactinemia. These data suggest that early postoperative hypoprolactinemia after transsphenoidal surgery for lactotroph PitNET is not only a good predictive factor for endocrinological remission but also no unfavorable effects on regular menstruation restoration.

KLHL14 and E-Cadherin Nuclear Co-Expression as Predicting Factor of Nonfunctioning PitNET Invasiveness: Preliminary Study.

Background/Objectives. Novel diagnostic and therapeutic approaches are needed to improve the clinical management of nonfunctioning pituitary neuroendocrine tumors (NF-PitNETs). Here, the expression of two proteins controlling the epithelial-mesenchymal transition (EMT)-an underlying NF-PitNET pathogenic mechanism-were analyzed as prognostic markers: E-cadherin (E-Cad) and KLHL14. Methods. The immunohistochemistry characterization of KLHL14 and E-Cad subcellular expression in surgical specimens of 12 NF-PitNET patients, with low and high invasiveness grades (respectively, Ki67+ < and ≥3%) was carried out. Results. The analysis of healthy vs. NF-PitNET tissues demonstrated an increased protein expression and nuclear translocation of KLHL14. Moreover, both E-Cad and KLHL14 shifted from a cytoplasmic (C) form in a low invasive NF-PitNET to a nuclear (N) localization in a high invasive NF-PitNET. A significant correlation was found between E-Cad/KLHL14 co-localization in the cytoplasm (p = 0.01) and nucleus (p = 0.01) and with NF-PitNET invasiveness grade. Conclusions. Nuclear buildup of both E-Cad and KLHL14 detected in high invasive NF-PitNET patients highlights a novel intracellular mechanism governing the tumor propensity to local invasion (Ki67+ ≥ 3%). The prolonged progression-free survival trend documented in patients with lower KLHL14 expression further supported such a hypothesis even if a larger cohort of NF-PitNET patients have to be analyzed to definitively recognize a key prognostic role for KLHL14.

High-throughput Screening for Cushing Disease: Therapeutic Potential of Thiostrepton via Cell Cycle Regulation.

Cushing disease is a life-threatening disorder caused by autonomous secretion of ACTH from pituitary neuroendocrine tumors (PitNETs). Few drugs are indicated for inoperative Cushing disease, in particular that due to aggressive PitNETs. To explore agents that regulate ACTH-secreting PitNETs, we conducted high-throughput screening (HTS) using AtT-20, a murine pituitary tumor cell line characterized by ACTH secretion. For the HTS, we constructed a live cell-based ACTH reporter assay for high-throughput evaluation of ACTH changes. This assay was based on HEK293T cells overexpressing components of the ACTH receptor and a fluorescent cAMP biosensor, with high-throughput acquisition of fluorescence images. We treated AtT-20 cells with compounds and assessed ACTH concentrations in the conditioned media using the reporter assay. Of 2480 screened bioactive compounds, over 50% inhibition of ACTH secreted from AtT-20 cells was seen with 84 compounds at 10 μM and 20 compounds at 1 μM. Among these hit compounds, we focused on thiostrepton (TS) and determined its antitumor effects in both in vitro and in vivo xenograft models of Cushing disease. Transcriptome and flow cytometry analyses revealed that TS administration induced AtT-20 cell cycle arrest at the G2/M phase, which was mediated by FOXM1-independent mechanisms including downregulation of cyclins. Simultaneous TS administration with a cyclin-dependent kinase 4/6 inhibitor that affected the cell cycle at the G0/1 phase showed cooperative antitumor effects. Thus, TS is a promising therapeutic agent for Cushing disease. Our list of hit compounds and new mechanistic insights into TS effects serve as a valuable foundation for future research.

Research progress on nonsteroidal anti-inflammatory drugs in the treatment of pituitary neuroendocrine tumors.

Pituitary neuroendocrine tumor is the third most common primary intracranial tumor. Its main clinical manifestations include abnormal hormone secretion symptoms, symptoms caused by tumor compression of the surrounding pituitary tissue, pituitary stroke, and other anterior pituitary dysfunction. Its pathogenesis is yet to be fully understood. Surgical treatment is still the main treatment. Despite complete resection, 10%-20% of tumors may recur. While dopamine agonists are effective in over 90% of prolactinomas, prolonged use and individual variations can lead to increased drug resistance and a gradual decline in efficacy, which ultimately requires surgical intervention. Nonsteroidal anti-inflammatory drugs reduce the production of inflammatory mediator prostaglandins by inhibiting the activity of cyclooxygenase and exert antipyretic, analgesic, antiplatelet, and anti-inflammatory effects. In recent years, many in-depth studies have confirmed the potential of nonsteroidal anti-inflammatory drugs as a preventive and antitumor agent. It has been extensively utilized in the prevention and treatment of various types of cancer. However, their specific mechanisms of action still need to be fully elucidated. This article summarizes recent research progress on the expression of cyclooxygenase in pituitary neuroendocrine tumors and the treatment of nonsteroidal anti-inflammatory drugs. It provides a feasible theoretical basis for further research on pituitary neuroendocrine tumors and explores potential therapeutic targets.

ScRNA sequencing technology for PitNET studies.

Pituitary neuroendocrine tumors (PitNETs) are common, most likely benign tumors with complex clinical characteristics related to hormone hypersecretion and/or growing sellar tumor mass. PitNET types are classified according to their expression of specific transcriptional factors (TFs) and hormone secretion levels. Some types show aggressive, invasive, and reoccurrence behavior. Current research is being conducted to understand the molecular mechanisms regulating these high-heterogeneous neoplasms originating from adenohypophysis, and single-cell RNA sequencing (scRNA-seq) technology is now playing an essential role in these studies due to its remarkable resolution at the single-cell level. This review describes recent studies on human PitNETs performed with scRNA-seq technology, highlighting the potential of this approach in revealing these tumor pathologies, behavior, and regulatory mechanisms.