Predictors of silent corticotroph adenoma recurrence; a large retrospective single center study and systematic literature review

Outcome of non-functioning ACTH pituitary tumors: silent does not mean indolent

INTRODUCTION

Silent corticotroph tumors (siACTH) represent a rare entity of pituitary tumors (PT), usually more aggressive than other PT. Few predictor factors of recurrence in the post-operative period have been proposed until now. This study aimed (1) to evaluate the clinical outcome of siACTH after surgery according to a five-tiered clinicopathological classification (2) to compare siACTH characteristics to ACTH-secreting macroadenomas (macroCD), and silent gonadotropinomas (siLH/FSH).

PATIENTS AND METHODS

Between 2008 and 2022, 29 siACTH out of 865 PT cases operated in one tertiary center were included. Clinical, paraclinical, histological, and surgical data were collected and compared to 25 macroCD and 143 siLH/FSH cases, respectively. The tumor grading was established according to both invasion (no = 1; yes = 2) and proliferation (no = a; yes = b). Progression-free survival was estimated using Kaplan-Meier method and log-rank test.

RESULTS

We identified 15 (51.7%) grade 1a, 11 (37.9%) grade 2a and 3 (10.3%) grade 2b siACTH with a trend for a 7-fold-time higher risk of progression/recurrence in grade 2b as compared to 1a (p = 0.06). The repartition of tumor grades was similar between the three subgroups, however a 5.7-fold-higher risk of progression was observed in grade 1a siACTH than in grade 1a siLH/FSH (p = 0.02). Compared to siLH/FSH, higher ACTH levels may help to preoperatively identify siACTH.

CONCLUSION

The five-tiered clinicopathological classification contribute to predict the risk of recurrence of operated siACTH tumors. Noteworthy, non-invasive and non-proliferative siACTH exhibit a less favorable outcomes than their siLH/FSH counterparts, which should prompt for a personalized follow up.

E-cadherin expression and gene expression profiles in corticotroph pituitary neuroendocrine tumor subtypes

Corticotroph adenomas/pituitary neuroendocrine tumors (PitNETs) are associated with significant morbidity and mortality. Predictors of tumor behavior have not shown high prognostic accuracy. For somatotroph adenomas/PitNETs, E-cadherin expression correlates strongly with prognosis. E-cadherin expression has not been investigated in other PitNETs. A retrospective chart review of adults with corticotroph adenomas/PitNETs was conducted to assess correlation between E-cadherin expression and tumor characteristics. In addition, gene expression microarray was performed in subset of tumors (n = 16). Seventy-seven patients were identified; 71% were female, with median age of cohort 45.2 years. Seventy-five percent had macroadenomas, of which 22% were hormonally active. Ninety-five percent of microadenomas were hormonally active. Adrenocorticotropic hormone granulation pattern by IHC identified 63% as densely granulated (DG) and 34% as sparsely granulated (SG). All microadenomas were DG (p < .001); 50% of macroadenomas were DG associated with increased tumor invasion compared to SG. E-cadherin IHC was positive in 80%, diminished in 17%, and absent in 20% and did not correlate with corticotroph PitNETs subtype, size, or prognosis. In contrast to the distinct transcriptomes of corticotroph PitNETs and normal pituitaries, a comparison of clinically active and silent corticotroph PitNETs demonstrated similar molecular signatures indicating their common origin, but with unique differences related to their secretory status.

Phenotype Transformation of PitNETs

Phenotype transformation in pituitary neuroendocrine tumors is a little-known and unpredictable clinical phenomenon. Previous studies have not clearly defined and systematically concluded on the causes of this rare phenomenon. Additionally, the mechanisms of phenotype transformation are not well known. We reviewed cases reported in the literature with the aim of defining phenotype transformation in pituitary neuroendocrine tumors. We present an overview of the wide spectrum of phenotype transformation and its clinical features. We also discuss findings on the potential mechanism of this rare transformation, which may be related to PC1/3, the bioactivity of secretory hormones, gene mutations and the plasticity of pituitary neuroendocrine tumors. Clinicians should be aware of this rare phenomenon and more studies on the underlying mechanisms are required.

Stereotactic radiosurgery for nonfunctioning pituitary tumor: A multicenter study of new pituitary hormone deficiency

BACKGROUND

Stereotactic radiosurgery (SRS) is used to treat recurrent or residual nonfunctioning pituitary neuroendocrine tumors (NFPA). The objective of the study was to assess imaging and development of new pituitary hormone deficiency.

METHODS

Patients treated with single-session SRS for a NFPA were included in this retrospective, multicenter study. Tumor control and new pituitary dysfunction were evaluated using Cox analysis and Kaplan-Meier curves.

RESULTS

A total of 869 patients (male 476 [54.8%], median age at SRS 52.5 years [Interquartile range (IQR): 18.9]) were treated using a median margin dose of 14Gy (IQR: 4) for a median tumor volume of 3.4 cc (IQR: 4.3). With a median radiological follow-up of 3.7 years (IQR: 4.8), volumetric tumor reduction occurred in 451 patients (51.9%), stability in 364 (41.9%) and 54 patients (6.2%) showed tumor progression.The probability of tumor control was 95.5% (95% Confidence Interval [CI]: 93.8-97.3) and 88.8% (95%CI: 85.2-92.5) at 5 and 10 years, respectively. A margin dose >14 Gy was associated with tumor control (Hazard Ratio [HR]:0.33, 95% CI: 0.18-0.60, P < 0.001). The probability of new hypopituitarism was 9.9% (95% CI: 7.3-12.5) and 15.3% (95% CI: 11-19.4) at 5 and 10 years, respectively. A maximum point dose >10 Gy in the pituitary stalk was associated with new pituitary hormone deficiency (HR: 3.47, 95% CI: 1.95-6.19). The cumulative probability of new cortisol, thyroid, gonadotroph, and growth hormone deficiency was 8% (95% CI: 3.9-11.9), 8.3% (95% CI: 3.9-12.5), 3.5% (95% CI: 1.7-5.2), and 4.7% (95% CI: 1.9-7.4), respectively at 10 years.

CONCLUSIONS

SRS provides long-term tumor control with a 15.3% risk of hypopituitarism at 10 years.

Is radiomics a useful addition to magnetic resonance imaging in the preoperative classification of PitNETs?

BACKGROUND

The WHO 2021 introduced the term pituitary neuroendocrine tumours (PitNETs) for pituitary adenomas and incorporated transcription factors for subtyping, prompting the need for fresh diagnostic methods. Current biomarkers struggle to distinguish between high- and low-risk non-functioning PitNETs. We explored if radiomics can enhance preoperative decision-making.

METHODS

Pre-treatment magnetic resonance (MR) images of patients who underwent surgery between 2015 and 2019 with available WHO 2021 classification were used. The tumours were manually segmented on the T1w, T1-contrast enhanced, and T2w images using 3D Slicer. One hundred Pyradiomic features were extracted from each MR sequence. Models were built to classify (1) somatotroph and gonadotroph PitNETs and (2) high- and low-risk subtypes of non-functioning PitNETs. Feature were selected independently from the MR sequences and multi-sequence (combining data from more than one MR sequence) using Boruta and Pearson correlation. Support vector machine (SVM), logistic regression (LR), random forest (RF), and multi-layer perceptron (MLP) were the classifiers used. Data imbalance was addressed using the Synthetic Minority Oversampling TEchnique (SMOTE). Performance of the models were evaluated using area under the receiver operating curve (AUC), accuracy, sensitivity, and specificity.

RESULTS

A total of 222 PitNET patients (train, n = 149; test, n = 73) were enrolled in this retrospective study. Multi-sequence-based LR model discriminated best between somatotroph and gonadotroph PitNETs, with a test AUC of 0.84, accuracy of 0.74, specificity of 0.81, and sensitivity of 0.70. Multi-sequence-based MLP model perfomed best for the high- and low-risk non-functioning PitNETs, achieving a test AUC of 0.76, accuracy of 0.67, specificity of 0.72, and sensitivity of 0.66.

CONCLUSIONS

Utilizing pre-treatment MRI and radiomics holds promise for distinguishing high-risk from low-risk non-functioning PitNETs based on the latest WHO classification. This could assist neurosurgeons in making critical decisions regarding surgery or alternative management strategies for PitNETs after further clinical validation.

Silent Corticotroph Staining Pituitary Neuroendocrine Tumors: Prognostic Significance in Radiosurgery

BACKGROUND AND OBJECTIVES

There is conflicting evidence on the significance of adrenocorticotrophic hormone (ACTH) staining in the prognosis of nonfunctioning pituitary neuroendocrine tumors (NFpitNETs). The objective of this study was to define the effect of ACTH immunostaining on clinical and radiographic outcomes of stereotactic radiosurgery (SRS) for NFpitNETs.

METHODS

This retrospective, multicenter study included patients managed with SRS for NFpitNET residuals. The patients were divided into 2 cohorts: (1) silent corticotroph (SC) for NFpitNETs with positive ACTH immunostaining and (2) non-SC NFpitNETs. Rates of local tumor control and the incidence of post-treatment pituitary and neurological dysfunction were documented. Factors associated with radiological and clinical outcomes were also analyzed.

RESULTS

The cohort included 535 patients from 14 centers with 84 (15.7%) patients harboring silent corticotroph NFpitNETs (SCs). At last follow-up, local tumor progression occurred in 11.9% of patients in the SC compared with 8.1% of patients in the non-SC cohort (P = .27). No statistically significant difference was noted in new-onset hypopituitarism rates (10.7% vs 15.4%, P = .25) or visual deficits (3.6% vs 1.1%, P = .088) between the 2 cohorts at last follow-up. When controlling for residual tumor volume, maximum dose, and patient age and sex, positive ACTH immunostaining did not have a significant correlation with local tumor progression (hazard ratio = 1.69, 95% CI = 0.8-3.61, P = .17).

CONCLUSION

In contemporary radiosurgical practice with a single fraction dose of 8-25 Gy (median 15 Gy), ACTH immunostaining in NFpitNETs did not appear to confer a significantly reduced rate of local tumor control after SRS.

A Novel Magnetic Resonance Imaging-Based Radiomics and Clinical Predictive Model for the Regrowth of Postoperative Residual Tumor in Non-Functioning Pituitary Neuroendocrine Tumor

Background and Objectives: To develop a novel magnetic resonance imaging (MRI)-based radiomics-clinical risk stratification model to predict the regrowth of postoperative residual tumors in patients with non-functioning pituitary neuroendocrine tumors (NF-PitNETs). Materials and Methods: We retrospectively enrolled 114 patients diagnosed as NF-PitNET with postoperative residual tumors after the first operation, and the diameter of the tumors was greater than 10 mm. Univariate and multivariate analyses were conducted to identify independent clinical risk factors. We identified the optimal sequence to generate an appropriate radiomic score (Rscore) that combined pre- and postoperative radiomic features. Three models were established by logistic regression analysis that combined clinical risk factors and radiomic features (Model 1), single clinical risk factors (Model 2) and single radiomic features (Model 3). The models' predictive performances were evaluated using receiver operator characteristic (ROC) curve analysis and area under curve (AUC) values. A nomogram was developed and evaluated using decision curve analysis. Results: Knosp classification and preoperative tumor volume doubling time (TVDT) were high-risk factors (p < 0.05) with odds ratios (ORs) of 2.255 and 0.173. T1WI&T1CE had a higher AUC value (0.954) and generated an Rscore. Ultimately, the AUC of Model 1 {0.929 [95% Confidence interval (CI), 0.865-0.993]} was superior to Model 2 [0.811 (95% CI, 0.704-0.918)] and Model 3 [0.844 (95% CI, 0.748-0.941)] in the training set, which were 0.882 (95% CI, 0.735-1.000), 0.834 (95% CI, 0.676-0.992) and 0.763 (95% CI, 0.569-0.958) in the test set, respectively. Conclusions: We trained a novel radiomics-clinical predictive model for identifying patients with NF-PitNETs at increased risk of postoperative residual tumor regrowth. This model may help optimize individualized and stratified clinical treatment decisions.

Aggressive Pituitary Tumors and Pituitary Carcinomas: From Pathology to Treatment

Aggressive pituitary tumors (APTs) and pituitary carcinomas (PCs) are heterogeneous with regard to clinical presentation, proliferative markers, clinical course, and response to therapy. Half of them show an aggressive course only many years after the first apparently benign presentation. APTs and PCs share several properties, but a Ki67 index greater than or equal to 10% and extensive p53 expression are more prevalent in PCs. Mutations in TP53 and ATRX are the most common genetic alterations; their detection might be of value for early identification of aggressiveness. Treatment requires a multimodal approach including surgery, radiotherapy, and drugs. Temozolomide is the recommended first-line chemotherapy, with response rates of about 40%. Immune checkpoint inhibitors have emerged as second-line treatment in PCs, with currently no evidence for a superior effect of dual therapy compared to monotherapy with PD-1 blockers. Bevacizumab has resulted in partial response (PR) in few patients; tyrosine kinase inhibitors and everolimus have generally not been useful. The effect of peptide receptor radionuclide therapy is limited as well. Management of APT/PC is challenging and should be discussed within an expert team with consideration of clinical and pathological findings, age, and general condition of the patient. Considering that APT/PCs are rare, new therapies should preferably be evaluated in shared standardized protocols. Prognostic and predictive markers to guide treatment decisions are needed and are the scope of ongoing research.

Cystic versus non-cystic silent corticotrophic adenomas: clinical and histological analysis of 62 cases after microscopic transsphenoidal surgery-a retrospective, single-center study

Silent corticotrophic adenomas (SCAs) represent a rare group of non-functioning adenomas with a potentially aggressive clinical course. Cystic component is a very common finding among SCAs, but its clinical relevance has not yet been investigated. The aim of this study was to analyze clinical features of cystic and non-cystic SCAs, perioperative complications after microscopic transsphenoidal surgery, clinical outcome after first and repeat surgery along with risk factors for recurrence. We conducted a retrospective analysis of 62 silent corticotrophic adenomas treated at our university medical center via microscopic transsphenoidal surgery between January 2008 and July 2019. Parameters investigated included histology, invasiveness, intratumoral haemorrhage or cystic component on MRI, perioperative alteration of visual field, tumor size, pre- and postoperative ACTH, FSH, GH, LH, TSH, prolactin, cortisol, free T4, free T3, IGF-1, estrogen and testosterone levels, perioperative complications, neoadjuvant and adjuvant therapy along with clinical outcomes. A total of 62 patients were analyzed. The mean follow up was 28.3 months. Tumors with a cystic component occur statistically significant more often among male than non-cystic (80.6% vs. 44.4%, p = 0.02) and display lower rates of cavernous sinus invasion and sphenoid sinus invasion were significantly lower for cystic lesions comparing to non-cystic tumors (42.3% vs. 69.4%, p = 0.04 and 3.8% vs. 47.2%, p < 0.001). GTR after MTS was not statistically significant higher by cystic SCAs (80% vs. 57.1%, p = 0.09). Cystic lesions were also associated with higher risk of hyperprolactinemia (19.4% vs. 2.8%, p = 0.02) and only densely granulated cystic SCAs presented with preoperative intratumoral hemorrhage (19.2% vs. 0%, p = 0.01). Mean duration of first surgery was significantly shorter for cystic SCAs (71.6(± 18.7) vs. 94.8(± 31.1) minutes, p = 0.01). Preoperative pituitary insufficiency (25% vs. 16.7%, p = 0.49), intraoperative CSF space opening (21.1% vs. 37.5%, p = 0.32), along with postoperative new pituitary insufficiency (15% vs. 10%, p = 0.67) or diabetes insipidus/SIADH (10% vs. 13.3%, p > 0.99) with histological markers such as Ki67 (21.1% vs. 13.8%, p = 0.70) and p53 expression (6.3% vs. 0%, p = 0.39) as well as mitotic rate (5.3% vs. 10.3%, p > 0.99) were comparable between both groups. The presence of cystic component did not affect the tumor recurrence (10% vs. 16%, p = 0.68). Mean duration of surgery was first surgeries was not statistically shorter than repeat surgeries (85.4 ± 29.1 vs. 93.8 ± 28 min, p = 0.15). Patients undergoing first surgery had a higher probability of gross total resection (74.4% vs. 30%, p = 0.01) and lower probability of intraoperative CSF space opening (26% vs. 58.3%, p = 0.04) as well as a lower rate of preoperative anterior pituitary insufficiency (20% vs. 58.3%, p = 0.01). The incidence of new postoperative anterior pituitary insufficiency (10% vs. 0%, p = 0.57) and transient diabetes insipidus/SIADH (12% vs. 8.3%, p > 0.99) between those groups were comparable. No statistical difference was observed between patients with remission and with recurrent tumor regarding cortisol and ACTH levels, incidence of different histological subgroups, invasively growing tumors and lesions with cystic components as well as the percentage of cases with increased Ki67 proliferation index, p53 expression and mitotic indices. Our study presents one of the largest available cohorts of SCAs after microscopic transsphenoidal surgery and first clinical analysis of cystic versus non-cystic SCAs so far. We also performed the first comparison of index and repeat surgeries for this tumor entity. Cystic tumors presented with characteristic clinical aspects like male predominance, higher risk of hyperprolactinemia as well as lower rates of cavernous sinus and sphenoid sinus invasion comparing to non-cystic lesions. Mean duration of first surgery was significantly shorter for cystic SCAs. Moreover preoperative intratumoral hemorrhage had 100% specificity and 60% sensitivity for densely granulated cystic SCAs. All these clinical hallmarks may suggest a novel subgroup of SCAs with distinct clinical and biological features, however further clinical and molecular investigations are required. Second surgeries are associated with a higher incidence of preoperative pituitary insufficiency, and a higher risk of subtotal resection, and a higher probability of CSF space opening intraoperatively compared to first surgeries. On the other hand, the risk of new postoperative pituitary insufficiency was higher after first surgeries. In our cohort of patients, no prognostic factor for recurrence among histological diagnosis, Ki67-proliferation index, p53 expression, number of mitoses, invasive growth or cystic lesions for SCAs could be detected.

The expression of glucocorticoid and mineralocorticoid receptors in pituitary tumors causing Cushing's disease and silent corticotroph tumors

OBJECTIVE

Pituitary neuroendocrine corticotroph tumors commonly cause Cushing's disease (CD) that results from increased adrenocorticotropic hormone (ACTH) secretion by the pituitary tumor and consequent increase of cortisol levels in blood. However, in some patients, corticotroph tumors remain clinically non-functioning. Cortisol secretion is regulated by the hypothalamic-pituitary-adrenal axis and includes a negative feedback between cortisol and ACTH secretion. Glucocorticoids reduce ACTH level both by hypothalamic regulation and acting on corticotrophs via glucocorticoid (GR) and mineralocorticoid (MR) receptors. The aim of the study was to determine the role of GR and MR expression at mRNA and protein levels in both functioning and silent corticotroph tumors.

METHODS

Ninety-five patients were enrolled, including 70 with CD and 25 with silent corticotroph tumors. Gene expression levels of NR3C1 and NR3C2 coding for GR and MR, respectively, were determined with qRT-PCR in the two tumor types. GR and MR protein abundance was assessed with immunohistochemistry.

RESULTS

Both GR and MR were expressed in corticotroph tumors. Correlation between NR3C1 and NR3C2 expression levels was observed. NR3C1 expression was higher in silent than in functioning tumors. In CD patients NR3C1 and NR3C2 levels were negatively correlated with morning plasma ACTH levels and tumor size. Higher NR3C2 was confirmed in patients with remission after surgery and in densely granulated tumors. Expression of both genes and GR protein was higher in USP8-mutated tumors. Similar relationship between USP8 mutations and expression levels were observed in analysis of silent tumors that also revealed a negative correlation between GR and tumor size and higher NR3C1 expression in densely granulated tumors.

CONCLUSIONS

Although the associations between gene/protein expression and patients clinical features are not strong, they consistently show an evident trend in which higher receptor expression corresponds to more favorable clinical characteristics.

Real-life clinical impact of a five-tiered classification of pituitary tumors

INTRODUCTION

Usually benign, pituitary tumors (PT) can be invasive and aggressive with a propensity to progress and/or recur. Trouillas's clinicopathological classification attempts to predict the evolutionary risk of a PT. In this study, we assessed the prognostic value of this classification in an independent patient cohort and analyzed its impact on treatment strategies.

PATIENTS AND METHODS

In this study, 607 patients operated on between 2008 and 2018 for a PT were included. Grading was established based on invasion, proliferative activity (Ki-67, mitotic index) and p53 positivity. The therapeutic management following surgery was analyzed. Progression-free survival (PFS) of the graded tumors was estimated (Kaplan-Meier method and log-rank test) and a multivariate analysis was performed (Cox regression model).

RESULTS

Grading identified non-invasive PT without (grade 1a: 303 cases) or with proliferative activity (grade 1b: 53 cases) and invasive PT without (grade 2a: 202 cases) or with proliferative activity (grade 2b: 49 cases). The mean follow-up was 47 ± 30 months (median: 38 months). Progression/recurrence occurred in 127 cases. Grades were significant and independent predictors of PFS (P < 0.001) with a 4.8-fold higher risk of progression/recurrence in grade 2b as compared to grade 1a. As second-line therapy, gamma knife or conventional radiotherapy controlled tumor growth in 91.6 and 100% of cases, respectively, irrespective of the grade. Proliferative tumors exposed the patient to a 9.5-fold higher risk of having ≥3 adjuvant therapeutic lines as compared to non-proliferative tumors.

DISCUSSION

Grading of a PT according to Trouillas's classification predicts its risk of progression and should advocate for a personalized therapeutic approach in invasive and proliferative tumors.

SIGNIFICANCE STATEMENT

This is the first study to assess, on a cohort of 607 well-characterized patients, the real-life therapeutic impact of the five-tiered clinicopathological classification of pituitary tumors. First, we validate that pituitary tumor grades predict the evolutionary risk of the tumor, with a significant higher risk of progression/recurrence in invasive and/or proliferative tumors (mean follow-up: 47 ± 30 months, median: 38 months). Moreover, our study provides evidence that patients with proliferative tumors have a higher risk to be retreated after primary surgery and point toward the fact that radiotherapy can successfully control tumor growth in case of progression or recurrence. Our findings advocate for a personalized therapeutic approach in clinically aggressive pituitary tumors.

The Expression of Cell Cycle-Related Genes in USP8-Mutated Corticotroph Neuroendocrine Pituitary Tumors and Their Possible Role in Cell Cycle-Targeting Treatment

Protein deubiquitinases USP8 and USP48 are known driver genes in corticotroph pituitary neuroendocrine tumors (PitNETs). USP8 mutations have pleiotropic effects that include notable changes in genes' expression. Genes involved in cell cycle regulation were found differentially expressed in mutated and wild-type tumors. This study aimed to verify difference in the expression level of selected cell cycle-related genes and investigate their potential role in response to cell cycle inhibitors. Analysis of 70 corticotroph PitNETs showed that USP8-mutated tumors have lower CDKN1B, CDK6, CCND2 and higher CDC25A expression. USP48-mutated tumors have lower CDKN1B and CCND1 expression. A lower p27 protein level in mutated than in wild-type tumors was confirmed that may potentially influence the response to small molecule inhibitors targeting the cell cycle. We looked for the role of USP8 mutations or a changed p27 level in the response to palbociclib, flavopiridol and roscovitine in vitro using murine corticotroph AtT-20/D16v-F2 cells. The cells were sensitive to each agent and treatment influenced the expression of genes involved in cell cycle regulation. Overexpression of mutated Usp8 in the cells did not affect the expression of p27 nor the response to the inhibitors. Downregulating or upregulating p27 expression in AtT-20/D16v-F2 cells also did not affect treatment response.

Recurrence Rate and Exploration of Clinical Factors after Pituitary Adenoma Surgery: A Systematic Review and Meta-Analysis based on Computer Artificial Intelligence System

Background

The first-line treatment for patients with any type of pituitary adenoma is trans-sphenoidal surgery. Considering the prevalence of the condition globally, the treatment is quite common. The recurrence of pituitary adenoma is a recognized occurrence in the medical field; however, there is limited comprehensive research and analysis of the predictive factors of recurrence rates and the clinical factors impacting relapse rates. Identifying the recurrence rates of pituitary adenomas and the clinical factors associated with them could help increase the remission rate by increasing focus on the specific aspects for early diagnosis and improved treatment.

Objective

The objective of the current systematic review and meta-analysis is to assess the recurrent rates based on previous studies and to explore the clinical factors after pituitary surgery.

Methods

A search was performed on PubMed, APA PsycINFO, Scopus, CENTRAL, and Google Scholar databases for English articles published from 1^st January 2010 to 1^st August 2022. Systematic reviews, meta-analysis, evidence syntheses, editorials, commentaries, preclinical studies, abstracts, theses, and preprints were excluded. Meta XL statistical software was used to conduct a prevalence meta-analysis.

Results

PubMed, PsycINFO, and Medline databases were searched. All of the articles were written between 2012 and 2022. In the beginning, 612 items were recognized. After removing duplicates and analyzing the remaining articles in terms of inclusion and exclusion criteria, 31 articles remained.

Conclusion

There is a relationship between recurrence rates and the follow-up period. There were conflicting results about the clinical factors after pituitary adenoma surgery, specifically age and tumor size. Some included studies that there was an association between macroadenomas and high recurrence rates. No study reported that gender was a clinical factor affecting pituitary adenoma surgery outcomes or the recurrence rate. Studies also reported that there was a correlation between the remnant tumor factor and the recurrence rates; adenoma remnants after surgery increased the risk of recurrence rates for patients.

Aggressive pituitary tumours and carcinomas, characteristics and management of 171 patients

OBJECTIVE

To describe clinical and pathological characteristics and treatment outcomes in a large cohort of aggressive pituitary tumours (APT)/pituitary carcinomas (PC).

DESIGN

Electronic survey August 2020-May 2021.

RESULTS

96% of 171 (121 APT, 50 PC), initially presented as macro/giant tumours, 6 were microadenomas (5 corticotroph). Ninety-seven tumours, initially considered clinically benign, demonstrated aggressive behaviour after 5.5 years (IQR: 2.8-12). Of the patients, 63% were men. Adrenocorticotrophic hormone (ACTH)-secreting tumours constituted 30% of the APT/PC, and the gonadotroph subtypes were under-represented. Five out of 13 silent corticotroph tumours and 2/6 silent somatotroph tumours became secreting. Metastases were observed after median 6.3 years (IQR 3.7-12.1) from diagnosis. At the first surgery, the Ki67 index was ≥3% in 74/93 (80%) and ≥10% in 38/93 (41%) tumours. An absolute increase of Ki67 ≥ 10% after median of 6 years from the first surgery occurred in 18/49 examined tumours. Tumours with an aggressive course from outset had higher Ki67, mitotic counts, and p53. Temozolomide treatment in 156/171 patients resulted in complete response in 9.6%, partial response in 30.1%, stable disease in 28.1%, and progressive disease in 32.2% of the patients. Treatment with bevacizumab, immune checkpoint inhibitors, and peptide receptor radionuclide therapy resulted in partial regression in 1/10, 1/6, and 3/11, respectively. Median survival in APT and PC was 17.2 and 11.3 years, respectively. Tumours with Ki67 ≥ 10% and ACTH-secretion were associated with worse prognosis.

CONCLUSION

APT/PCs exhibit a wide and challenging spectrum of behaviour. Temozolomide is the first-line chemotherapy, and other oncological therapies are emerging. Treatment response continues to be difficult to predict with currently studied biomarkers.

Application of “mosiac sign” on T2-WI in predicting the consistency of pituitary neuroendocrine tumors

Purpose

Tumor consistency is important for pituitary neuroendocrine tumors (PitNETs) resection to improve surgical outcomes. In this study, we evaluated the T2-WI of PitNETs and defined a specific T2-WI signaling manifestation, the “Mosaic sign,” to predict tumor consistency and resection of PitNETs.

Design

A retrospective review of MRI and tumor histology of 137 consecutive patients who underwent endoscopic endonasal resection for PitNETs was performed.

Methods

The “Mosaic sign” was defined by the ratio of the tumor itself T2-WI signals, and characterized by multiple intratumor hyperintense dots. The degree of tumor resection was an assessment by postoperative MRI examination. The presence of the “Mosaic sign” was compared with patients' basic information, tumor consistency, tumor pathological staining, and surgical result. To determine whether the presence or absence of “Mosaic sign” could predict tumor consistency and guide surgical resection of tumors.

Results

Statistical analysis showed that the consistency of the tumor and the degree of resection were correlated with the “Mosaic sign”. In the 137 cases of T2-WI, 43 had “Mosaic sign”, 39 cases had soft tumor consistency, and 4 were classified as fibrous, of which 42 were completely resected and 1 was subtotal resected. Of the 94 patients without “Mosaic sign”, the consistency of tumor of 54 cases were classified as soft, the remaining 40 cases were fibrous, 80 cases were completely resected, and 14 cases were subtotal resected. Postoperative cerebrospinal fluid leakage occurred in 1 patient. The number of corticotroph adenomas in the group of “Mosaic sign” was higher, with the statistical difference between the two groups (P = 0.0343).

Conclusions

The presence of the “Mosaic sign” in T2-WI may provide preoperative information for pituitary adenomas consistency and effectively guide surgical approaches.

Silent Corticotroph and Somatotroph Double Pituitary Adenoma: A Case Report and Review of Literature

Clinically silent double pituitary adenomas consisting of corticotroph and somatotroph cells are an exceedingly rare clinical finding. In this report, we present the case of a 28-year-old man with a 1-year history of recurrent headaches. Imaging revealed a 2.1 (anterior-posterior) × 2.2 (transverse) × 1.3 (craniocaudal) cm pituitary adenoma invading into the left cavernous sinus and encasing the left internal carotid artery. Endoscopic transnasal resection was performed without complications. Immunohistochemical staining revealed a double adenoma consisting of distinct sparsely granulated somatotroph and densely granulated corticotroph cells that were positive for growth hormone and adrenocorticotropic hormone, respectively. K _i -67 index labeling revealed a level of 6% within the corticotroph adenoma. No increase in serum growth hormone or adrenocorticotropic hormone was found, indicating a clinically silent double adenoma. While transsphenoidal surgery remains a first-line approach for silent adenomas presenting with mass effects, increased rates of proliferative markers, such as the K _i -67 index, provide useful insight into the clinical course of such tumors. Determining the K _i -67 index of silent pituitary adenomas could be valuable in predicting recurrence after initial surgical resection and identifying tumors that are at an increased risk of needing additional therapeutic interventions or more frequent surveillance imaging.

Distribution of E- and N-cadherin in subgroups of non-functioning pituitary neuroendocrine tumours

PURPOSE

Clinically non-functioning pituitary neuroendocrine tumours (NF-PitNETs) present a varying degree of aggressiveness, and reliable prognostic markers are lacking. We aimed to characterise the distribution of E- and N-cadherin in corticotroph, PIT1 and null-cell NF-PitNETs, and link it to the course of the tumours.

METHODS

The distribution of E- and N-cadherin was investigated by immunohistochemistry in a retrospective cohort of 30 tumours of the less common NF-PitNETs (corticotroph (N = 18), PIT1 (N = 8) and null-cell PitNETs (N = 4)). Immunoreactive scores (IRS) were compared to previously presented cohorts of gonadotroph NF-PitNETs (N = 105) and corticotroph functioning PitNETs (N = 17).

RESULTS

We found a low IRS for the extra-cellular domain of E-cadherin (median 0 (IQR 0-0, N = 135)), a medium to high IRS for the intra-cellular domain of E-cadherin (median 6 (IQR 4-9)) and a high IRS for N-cadherin (median 12 (IQR 10.5-12)) throughout the cohort of NF-PitNETs. The corticotroph NF-PitNETs presented a higher IRS for both the extra- and intra-cellular domain of E-cadherin (median 0 (IQR 0-1) and median 9 (IQR 6-12), respectively) than the gonadotroph NF-PitNETs (p < 0.001 for both comparisons). Presence of nuclear E-cadherin was associated with a weaker staining for the intra-cellular domain of E-cadherin (median 4 (IQR 0.5-6) and median 9 (IQR 9-12), for tumours with and without nuclear E-cadherin, respectively), and with a lower rate of re-intervention (p = 0.03).

CONCLUSIONS

Considering our results and the benign course of NF-PitNETs, we suggest that a high N-cadherin and downregulation of membranous E-cadherin are not associated with a more aggressive tumour behaviour in these subgroups of NF-PitNETs.

Quantitative Ubiquitinomics Revealed Abnormal Ubiquitinated ATP7A Involved in Down-Regulation of ACTH in Silent Corticotroph Adenomas

Ubiquitination is reported to be a critical biological event on ACTH secretion in corticotroph adenomas. However, the effect of ubiquitylation on ACTH secretion in silent corticotroph adenomas (SCAs) remains unclear. The aim of our study was to explore the mechanism of decreased secretion of ACTH in SCAs with ubiquitinomics. The differently expressed ubiquitinated proteins between SCAs and functioning corticotroph adenomas (FCAs) were identified by 4D label-free mass spectrometer, followed by bioinformatics analysis. The function of the candidate ubiquitinated protein ATP7A (K333) was validated in AtT20 cells. A total of 111 ubiquitinated sites corresponding to 94 ubiquitinated proteins were typically different between SCAs and FCAs. Among all the ubiquitinated sites, 102 showed decreased ubiquitination in SCAs, which mapped to 85 ubiquitinated proteins. Pathway enrichment analysis revealed that ubiquitinated proteins were mainly enriched in vesicle pathway and protein secretion pathway. ATP7A (K333) was one of the proteins enriched in vesicle pathway and protein secretion pathway with decreased ubiquitination level in SCAs. In vitro assay indicated that both ATP7A siRNA and omeprazole (ATP7A protein inhibitor) increased the secretion of ACTH in AtT20 cell supernatant compared to control groups (p<0.05). These results indicated that ATP7A might be related to the abnormal expression of ACTH in SCAs and potential for the treatment of SCAs.

Prognostic Factors for Recurrence in Pituitary Adenomas: Recent Progress and Future Directions

Pituitary adenomas (PAs) are benign lesions; nonetheless, some PAs exhibit aggressive behaviors, which lead to recurrence. The impact of pituitary dysfunction, invasion-related risks, and other complications considerably affect the quality of life of patients with recurrent PAs. Reliable prognostic factors are needed for recurrent PAs but require confirmation. This review summarizes research progress on two aspects—namely, the clinical and biological factors (biomarkers) for recurrent PAs. Postoperative residue, age, immunohistological subtypes, invasion, tumor size, hormone levels, and postoperative radiotherapy can predict the risk of recurrence in patients with PAs. Additionally, biomarkers such as Ki-67, p53, cadherin, pituitary tumor transforming gene, matrix metalloproteinase-9, epidermal growth factor receptor, fascin actin-bundling protein 1, cyclooxygenase-2, and some miRNAs and lncRNAs may be utilized as valuable tools for predicting PA recurrence. As no single marker can independently predict PA recurrence, we introduce an array of comprehensive models and grading methods, including multiple prognostic factors, to predict the prognosis of PAs, which have shown good effectiveness and would be beneficial for predicting PA recurrence.

lncRNA KCNQ1OT1 Promotes EMT, Angiogenesis, and Stemness of Pituitary Adenoma by Upregulation of RAB11A

This study is aimed at investigating the effect and mechanism of long noncoding RNA (lncRNA) KCNQ1OT1 on pituitary adenoma (PA). The KCNQ1OT1 expression in invasive and noninvasive PA tissues was detected by real-time fluorescence quantitative polymerase chain reaction (qPCR). The effects of KCNQ1OT1 on the proliferation of PA cells, namely, GH3 and HP75, were detected by CCK-8 experiment. The Transwell assay detected the effect of KCNQ1OT1 on the invasion of GH3 and HP75 cells. The effect of KCNQ1OT1 on the clonal formation ability was detected by clonal formation experiment. The double luciferase reporter assay and the miRNA pull down assay verified the binding of KCNQ1OT1 to miR-140-5p. Meanwhile, the regulatory effect of miR-140-5p on RAB11A was verified. qPCR results showed that KCNQ1OT1 was significantly increased in invasive PA compared with noninvasive PA tissues. Knockdown KCNQ1OT1 inhibited PA cell stemness, angiogenesis, and EMT. In addition, knockdown KCNQ1OT1 inhibited the proliferation, invasion, and clonal formation of PA. miR-140-5p is the target gene of KCNQ1OT1. miR-140-5p targets RAB11A directly. RAB11A can mediate the biological effects of KCNQ1OT1. Meanwhile, lncRNA KCNQ1OT1 can promote the EMT and cellular stemness of PA. Its mechanism of action is realized by inhibiting miR-140-5p. This result can provide a molecular basis for the further study of PA.

Difference in miRNA Expression in Functioning and Silent Corticotroph Pituitary Adenomas Indicates the Role of miRNA in the Regulation of Corticosteroid Receptors

Corticotroph pituitary adenomas commonly cause Cushing’s disease (CD), but some of them are clinically silent. The reason why they do not cause endocrinological symptoms remains unclear. We used data from small RNA sequencing in adenomas causing CD (n = 28) and silent ones (n = 20) to explore the role of miRNA in hormone secretion and clinical status of the tumors. By comparing miRNA profiles, we identified 19 miRNAs differentially expressed in clinically functioning and silent corticotroph adenomas. The analysis of their putative target genes indicates a role of miRNAs in regulation of the corticosteroid receptors expression. Adenomas causing CD have higher expression of hsa-miR-124-3p and hsa-miR-135-5p and lower expression of their target genes NR3C1 and NR3C2. The role of hsa-miR-124-3p in the regulation of NR3C1 was further validated in vitro using AtT-20/D16v-F2 cells. The cells transfected with miR-124-3p mimics showed lower levels of glucocorticoid receptor expression than control cells while the interaction between miR-124-3p and NR3C1 3′ UTR was confirmed using luciferase reporter assay. The results indicate a relatively small difference in miRNA expression between clinically functioning and silent corticotroph pituitary adenomas. High expression of hsa-miR-124-3p in adenomas causing CD plays a role in the regulation of glucocorticoid receptor level and probably in reducing the effect of negative feedback mediated by corticosteroids.

Pituitary Society Delphi Survey: An international perspective on endocrine management of patients undergoing transsphenoidal surgery for pituitary adenomas

PURPOSE

In adults and children, transsphenoidal surgery (TSS) represents the cornerstone of management for most large or functioning sellar lesions with the exception of prolactinomas. Endocrine evaluation and management are an essential part of perioperative care. However, the details of endocrine assessment and care are not universally agreed upon.

METHODS

To build consensus on the endocrine evaluation and management of adults undergoing TSS, a Delphi process was used. Thirty-five statements were developed by the Pituitary Society's Education Committee. Fifty-five pituitary endocrinologists, all members of the Pituitary Society, were invited to participate in two Delphi rounds and rate their extent of agreement with statements pertaining to perioperative endocrine evaluation and management, using a Likert-type scale. Anonymized data on the proportion of panelists' agreeing with each item were summarized. A list of items that achieved consensus, based on predefined criteria, was tabulated.

RESULTS

Strong consensus (≥ 80% of panelists rating their agreement as 6-7 on a scale from 1 to 7) was achieved for 68.6% (24/35) items. If less strict agreement criteria were applied (ratings 5-7 on the Likert-type scale), consensus was achieved for 88% (31/35) items.

CONCLUSIONS

We achieved consensus on a large majority of items pertaining to perioperative endocrine evaluation and management using a Delphi process. This provides an international real-world clinical perspective from an expert group and facilitates a framework for future guideline development. Some of the items for which consensus was not reached, including the assessment of immediate postoperative remission in acromegaly or Cushing's disease, represent areas where further research is needed.

An Update on Silent Corticotroph Adenomas: Diagnosis, Mechanisms, Clinical Features, and Management

Simple Summary

The 2017 World Health Organization classification of endocrine tumors defines pituitary adenomas based on their cell lineages. T-PIT can serve as a complimentary tool for further identification of silent corticotroph adenomas (SCAs). Unlike functioning corticotroph adenomas in patients with Cushing’s disease, SCAs present no clinical and biochemical features of Cushing’s syndrome. SCAs have been shown to exhibit a more aggressive course characterized by a higher probability of recurrence and resistance to conventional treatment due to their intrinsic histological features. The aim of our review is to offer an update on the diagnosis, mechanisms, clinical features and management of SCAs. Studies of the molecular mechanisms of SCA pathogenesis will provide new directions for the diagnosis and management of SCAs.

Abstract

With the introduction of 2017 World Health Organization (WHO) classification of endocrine tumors, T-PIT can serve as a complementary tool for identification of silent corticotroph adenomas (SCAs) in some cases if the tumor is not classifiable by pituitary hormone expression in pathological tissue samples. An increase of the proportion of SCAs among the non-functioning pituitary adenomas (NFPAs) has been witnessed under the new rule with the detection of T-PIT-positive ACTH-negative SCAs. Studies of molecular mechanisms related to SCA pathogenesis will provide new directions for the diagnosis and management of SCAs. A precise pathological diagnosis can help clinicians better identify SCAs. Understanding clinical features in the context of the pathophysiology of SCAs is critical for optimal management. It could provide information on appropriate follow-up time and aid in early recognition and treatment of potentially aggressive forms. Management approaches include surgical, radiation, and/or medical therapies.

A clinicoradiological analysis of silent corticotroph adenomas after the introduction of pituitary-specific transcription factors

BACKGROUND

Silent corticotroph adenomas (SCAs) are a rare subtype of non-functional pituitary adenoma. While it has been suggested that they are more aggressive and recur more frequently following excision, there is limited literature on the optimum treatment strategy for these tumors, especially regarding the role of radiation therapy in incompletely resected tumors.

METHOD

We assimilated data from 62 SCAs and 238 other non-functional adenomas (ONAs), defined according to the WHO 2017 criteria that incorporates transcription factor analysis. We compared their clinicoradiological characteristics, such as hormonal levels, tumor configuration, size, and invasiveness. For 52 SCAs and 205 ONAs with serial follow-up imaging, we studied outcomes for progression after subtotal resection with or without radiation therapy or recurrence after gross total resection. Kaplan Meier analysis for recurrence or progression was used to determine the need for a differential treatment strategy for SCAs compared with other non-functional adenomas specifically concerning the role of radiotherapy.

RESULTS

Patients with SCAs present at a younger age than ONAs (43.9 years vs. 48.2 years, p = 0.014), with larger (14.9 cc vs. 9.7 cc, p = 0.006) and more invasive adenomas (61.2% vs. 45.8%, p = 0.021). Overall, SCAs are more likely to recur or progress (48.7 vs. 15.7%, p < 0.001) following excision than ONAs, with significantly poorer event-free survival (Log rank test p < 0.001). Early adjuvant radiotherapy provides favorable outcomes among SCAs with postoperative residual tumor, on par with ONAs. Multivariate analysis identified male gender (HR: 2.217; p = 0.017), MIB index ≥ 3% (HR: 2.116; p = 0.012), and SCA tumor pathology (HR: 3.787; p < 0.001) as factors predicting recurrence.

CONCLUSIONS

Based on the results of this retrospective, single-center review of 300 non-functional adenomas, we conclude that silent corticotroph adenomas are an aggressive subtype of non-functional pituitary adenomas that are larger, more likely to be invasive, and tend to recur more frequently after a subtotal excision compared with other non-functional adenomas. A gross total resection must be attempted whenever possible and earlier adjuvant radiation is recommended when re-surgery for residual tumor is difficult.

Clinically non-functioning pituitary adenomas

Clinically non functioning pituitary adenomas (NFPAs) include all pituitary adenomas that are not hormonally active. They are not associated with clinical syndromes such as amenorrhea-galactorrhea (prolactinomas), acromegaly, Cushing's disease or hyperthyroidism (TSH-secreting adenomas) and are therefore usually diagnosed by signs and symptoms related to a mass effect (headache, visual impairment, sometimes pituitary apoplexy), but also incidentally. Biochemical work up often documents several pituitary insufficiencies. In histopathology, the majority of NFPAs are gonadotroph. In the absence of an established medical therapy, surgery is the mainstay of treatment, unless contraindicated or in particular situations (e.g. small incidentalomas, distance from optic pathways). Resection, generally via a trans-sphenoidal approach (with the help of an endoscope), should be performed by a neurosurgeon with extensive experience in pituitary surgery, in order to maximize the chances of complete resection and to minimize complications. If a tumor remnant persists, watchful waiting is preferred to routine radiotherapy, as long as the tumor residue does not grow and is distant from the optic pathways. NFPA can sometimes recur even after complete resection, but predicting the individual risk of tumor remnant progression is difficult. Postoperative irradiation is only considered in case of residual tumor growth or relapse, due to its potential side effects.

Clinical profiles of silent corticotroph adenomas compared with silent gonadotroph adenomas after adopting the 2017 WHO pituitary classification system

PURPOSE

Silent corticotroph adenomas (SCAs) can be redefined according to the 2017 World Health Organization pituitary classification system with the introduction of T‑PIT, a transcription factor. We studied the clinical features of these redefined SCAs.

METHODS

We compared 112 patients with SCAs and 198 patients with silent gonadotroph adenomas (SGAs) who underwent surgery from January 2019 to May 2020.

RESULTS

The prevalence of SCAs increased from 21.3 to 30.2% under the new classification rules. T-PIT-positive, adrenocorticotropic hormone-negative SCAs and T-PIT-positive, adrenocorticotropic hormone-positive SCAs exhibited similar clinical features. SCAs exhibited significant female preponderance (90.2% vs. 29.8%, P < 0.0001); more frequent invasion (36.6% vs. 7.6%, P < 0.0001), especially multiple-site invasion (P < 0.0001); and marked cystic changes on imaging compared with SGAs (54.5% vs. 19.2%, P < 0.0001). SCAs had a softer tumor consistency (89.2% vs. 61.1%, P < 0.0001). Gross total resection was achieved in 66.1% of SCAs and 66.2% of SGAs (P > 0.9999). The overall recurrence/progression rates of SCAs and SGAs were 9.8% and 6.6% at 14.1 and 13.5 months of follow-up, respectively (P = 0.3765). The proportion of patients with more than two recurrences requiring multiple surgeries and radiation was similar between SCAs and SGAs (7.1% vs. 3.0%, P = 0.1514). However, multiple recurrences of SCAs affected younger patients than SGAs (39.0 vs. 53.5 years, P = 0.0433).

CONCLUSIONS

The prevalence of SCAs increased with the introduction of T-PIT. SCAs and SGAs exhibited comparable size and recurrence/progression rates, but SCAs showed increased invasion and more marked cystic change. Aggressive SCAs tended to affect younger patients. Close long-term monitoring for SCA recurrence/progression is required.

The silent variants of pituitary tumors: demographic, radiological and molecular characteristics

INTRODUCTION

Tumors of the anterior pituitary gland (PTs) are mostly benign tumors with a low prevalence, which has nevertheless increased with advances in brain radiology techniques. Nearly half of PTs are not associated with a clinical endocrine syndrome. These tumors have been indistinctly named non-functioning pituitary adenomas (NFPAs) or silent pituitary tumors (SPTs) and the mechanisms of silencing are not fully known.

AIM

To study the frequency and characterize the silent variant of PTs in a large local series, and to assess their pituitary adenohypophyseal gene expression.

METHODS

This observational, cross-sectional study was performed in a Pituitary Tumor Center of Excellence and involved 268 PTs. After identifying the different subtypes according to the immunohistochemical (IHC) expression of adenohypophyseal hormones, we studied their gene expression by RT-qPCR.

RESULTS

We found that silent tumors were larger and more invasive, but not more proliferative than their functional counterparts. The RT-qPCR complements the IHC typification of PTs, reducing the proportion of null-cell subtype. Finally, some silent PT subtype variants showed lower specific adenohypophyseal hormone gene expression than their functional counterparts, which may contribute to the absence of endocrine manifestations.

CONCLUSIONS

This paper highlights the importance of identifying the silent variant of the PTs subtypes. As expected, silent tumors were larger and more invasive than their functioning counterparts. However, there was no difference in the proliferation activity between them. Finally, the lower specific gene expression in the silent than in the functioning counterparts of some PTs subtypes gives insights into the silencing mechanisms of PTs.

Identifying Glucocorticoid Insufficiency in Silent Corticotroph Adenoma with Elevated Adrenocorticotropic Hormone

Silent corticotroph adenoma (SCA) is as an aggressive pituitary tumor. A 48 year old man developed hypogonadotrophic hypogonadism. The basal morning adrenocorticotropic hormone (ACTH) was elevated, but the basal morning and peak after ACTH (1-24) stimulation cortisol were normal. A 3.7 cm sellar mass with evidence of internal hemorrhage, encasement of the right internal carotid artery, and invasion of the right cavernous sinus were identified, resected, and stained positive for ACTH. Over the next 5 years, the basal morning ACTH and cortisol were normal, and imaging revealed the presence of a small residual tumor. One year later, the patient became fatigued and nauseated, with elevated ACTH. An overnight metyrapone stimulation test (OMST) revealed glucocorticoid insufficiency, without further increase in ACTH. Symptoms resolved with hydrocortisone treatment. This case study suggests that SCA can secrete an ACTH precursor that is detected by clinical assays but is not active biologically. Postoperative OMST reveals glucocorticoid insufficiency in this context.

Silent corticotroph pituitary adenomas: clinical characteristics, long-term outcomes, and management of disease recurrence

OBJECTIVE

Silent corticotroph adenomas (SCAs) are a distinct subtype of nonfunctioning pituitary adenomas (NFAs) that demonstrate positive immunohistochemistry for adrenocorticotropic hormone (ACTH) without causing Cushing's disease. SCAs are hypothesized to exhibit more aggressive behavior than standard NFAs. The authors analyzed their institution's surgical experience with SCAs in an effort to characterize rates of invasion, postoperative clinical outcomes, and patterns of disease recurrence and progression. The secondary objectives were to define the best treatment strategies in the event of tumor recurrence and progression.

METHODS

A retrospective analysis of patients treated at the authors' institution identified 100 patients with SCAs and 841 patients with NFAs of other subtypes who were treated surgically from 2000 to 2019. Patient demographics, tumor characteristics, surgical and neuroimaging data, rates of endocrinopathy, and neurological outcomes were recorded. Cohorts of patients with SCAs and patients with standard NFAs were compared with regard to these characteristics and outcomes.

RESULTS

The SCA cohort presented with cranial neuropathy (13% vs 5.7%, p = 0.0051) and headache (53% vs 42.3%, p = 0.042) compared to the NFA cohort, despite similar rates of apoplexy. The SCA cohort included a higher proportion of women (SCA 60% vs NFA 45.8%, p = 0.0071) and younger age at presentation (SCA 50.5 ± 13.3 vs NFA 54.6 ± 14.9 years of age, p = 0.0082). Reoperations were comparable between the cohorts (SCA 16% vs NFA 15.7%, p = 0.98). Preoperative pituitary function was comparable between the cohorts with the exception of higher rates of preoperative panhypopituitarism in NFA patients (2% vs 6.1%, respectively; p = 0.0033). The mean tumor diameter in SCA patients was 24 ± 10.8 mm compared to 26 ± 11.3 mm in NFA patients (p = 0.05). Rates of cavernous sinus invasion were higher in the SCA group (56% vs 49.7%), although this result did not reach statistical significance. There were no significant differences in extent of resection, intraoperative CSF leak rates, endocrine or neurological outcomes, or postoperative complications. Ki-67 rates were significantly increased in the SCA cohort (2.88 ± 2.79) compared to the NFA cohort (1.94 ± 1.99) (p = 0.015). Although no differences in overall rates of progression or recurrence were noted, SCAs had a significantly lower progression-free survival (24.5 vs 51.1 months, p = 0.0011). Among the SCA cohort, progression was noted despite the use of adjuvant radiosurgery in 33% (n = 4/12) of treated tumors. Adequate tumor control was not achieved in half (n = 6) of the SCA progression cohort despite radiosurgery or multiple resections.

CONCLUSIONS

In this study, to the authors' knowledge the largest surgical series to assess outcomes in SCAs to date, the findings suggest that SCAs are more biologically aggressive tumors than standard NFAs. The progression-free survival duration of patients with SCAs is only about half that of patients with other NFAs. Therefore, close neuroimaging and clinical follow-up are warranted in patients with SCAs, and residual disease should be considered for early postoperative adjuvant radiosurgery, particularly in younger patients.

Guidelines in the management of CNS tumors

INTRODUCTION

Evidence-based, clinical practice guidelines in the management of central nervous system tumors (CNS) continue to be developed and updated through the work of the Joint Section on Tumors of the Congress of Neurological Surgeons (CNS) and the American Association of Neurological Surgeons (AANS).

METHODS

The guidelines are created using the most current and clinically relevant evidence using systematic methodologies, which classify available data and provide recommendations for clinical practice.

CONCLUSION

This update summarizes the Tumor Section Guidelines developed over the last five years for non-functioning pituitary adenomas, low grade gliomas, vestibular schwannomas, and metastatic brain tumors.

Clinical Parameters of Silent Corticotroph Adenomas With Positive and Negative Adrenocorticotropic Hormone Immunostaining: A Large Retrospective Single-Center Study of 105 Cases

Purpose

To investigate the different clinical characteristics of silent corticotroph adenomas (SCAs) with positive and negative adrenocorticotropic hormone (ACTH) immunostaining, and to explore the value of pituitary-restricted transcription factor (Tpit) immunostaining for diagnosing SCAs.

Methods

The clinical materials of patients with SCAs who had a typical pathological feature with positive Tpit immunostaining and positive/negative ACTH immunostaining, and without clinical features and biochemical evidence for Cushing's Syndrome in our center from April 2018 to March 2019 were analyzed retrospectively. The differences in clinical characteristics and surgical results between ACTH-positive and -negative SCAs were explored.

Results

A total of one hundred and five patients (94.3% female) with SCAs were included. There were 66 SCAs with ACTH-negative (66/105, 62.9%), and 39 SCAs with ACTH-positive (39/105, 37.1%). Cases with ACTH-negative SCAs were more likely to have lower ACTH levels (27.5 ± 24.0 vs. 54.4 ± 58.6, P = 0.011), more multiple microcysts (81.8% vs. 61.5%, P = 0.022) and lower levels of Ki-67 expression (low expression rate 90.9% vs. 74.4%, P = 0.023). No statistical significant differences were observed between patients with ACTH-positive and -negative SCAs regarding gender (97.0% vs. 89.7%, P = 0.192), age (50.3 ± 10.3 vs. 49.0 ± 11.2, P = 0.543), surgical history (16.7% vs. 23.1%, P = 0.419), suprasellar extension (66.7% vs. 74.4%, P = 0.408), sphenoid sinus extension (51.5% vs. 56.4%, P = 0.627), cavernous sinus invasion (75.8% vs. 66.7%, P = 0.314), large cyst on Magnetic Resonance Imaging (MRI) (47.0% vs. 61.5%, P = 0.149), or gross total resection rate (42.4% vs. 51.3%, P = 0.379).

Conclusions

ACTH-negative SCAs were observed to be more clinically silent and more likely to demonstrate multiple microcysts on MRI. The prevalence of SCAs, especially ACTH-negative SCAs, proved to be substantially underestimated and thus they should be given enough attention in consideration of the high aggressiveness of this subtype of refractory pituitary adenoma (PA).

UPLC-MS/MS-based Lipidomic Profiles Revealed Aberrant Lipids Associated with Invasiveness of Silent Corticotroph Adenoma

CONTEXT

The accumulation of aberrant lipids and abnormal lipid metabolism in silent corticotroph adenomas (SCAs) could contribute to changes in clinical phenotypes, especially sphenoid sinus invasion.

OBJECTIVE

To systematically investigate lipidomic and transcriptomic alterations associated with invasiveness and their potential molecular mechanisms in SCAs and to provide candidate biomarkers for predicting invasiveness and novel treatment options for invasive SCAs by targeting lipids.

METHODS

Fifty-four SCAs (34 invasive/20 noninvasive) were subjected to lipidomic analysis based on ultraperformance liquid chromatography mass spectrometry, and 42 clinically nonfunctioning pituitary adenomas (23 invasive/19 noninvasive) were subjected to transcriptomic analysis. Differential analysis was performed to determine differential lipids and genes between invasive and noninvasive tumors. A functionally connected network was constructed with the molecular pathways as cores. Multiple machine learning methods were applied to identify the most critical lipids, which were further used to construct a lipidomic signature to predict invasive SCAs by multivariate logistic regression, and its performance was evaluated by receiver operating characteristic analysis.

RESULTS

Twenty-eight differential lipids were identified, and a functionally connected network was constructed with 2 lipids, 17 genes, and 4 molecular pathways. Connectivity Map (CMap) analysis further revealed 32 potential drugs targeting 4 genes and related pathways. The 4 most critical lipids were identified as risk factors contributing to the invasive phenotype. A lipidomic signature was constructed and showed excellent performance in discriminating invasive and noninvasive SCAs.

CONCLUSIONS

The lipidomic signature could serve as a promising predictor for the invasive SCA phenotype and provide potential therapeutic targets for SCAs.

Recent Understanding and Future Directions of Recurrent Corticotroph Tumors

Corticotroph tumors (CTs) are pituitary neoplasms arising from the Tpit lineage, which may or not express adrenocorticotrophic hormone (ACTH). Functioning CTs cause Cushing's disease (CD), which has high morbidity and mortality due to hypercortisolemia. "Non-functioning" or silent CTs (SCT) and the Crooke's cell subtypes do not cause CD and may be asymptomatic until manifested by compressive symptoms and are more frequently found as macroadenoma. Both tend toward more aggressive behavior, recurrence, and a higher rate of malignant transformation to pituitary carcinoma. Tumorigenesis involves genetic, epigenetic, and post-transcriptional disruption of cell-cycle regulators, which increase cell proliferation, POMC overexpression, ACTH transcription, and/or hypersecretion. Furthermore, functioning CTs develop resistance to glucocorticoid-mediated negative feedback on ACTH secretion, through increased expression of testicular orphan nuclear receptor 4 (TR4), heat-shock protein 90 (HSP90), and loss-of-function mutation of CDK5 and ABL enzyme substrate 1 (CABLES1) gene. Overt autonomous hypercortisolemia is difficult to control, and multiple diagnostic studies and therapeutic modalities are commonly required. Cell-cycle regulation depends mainly on p27, cyclin E, cyclin-dependent kinases (CDKs), and the retinoblastoma protein (Rb)/E2F1 transcription factor complex. Gain-of-function mutations of ubiquitin-specific protease (USP) 8, USP48, and BRAF genes may subsequently cause overexpression of epithelial growth factor receptor (EGFR), and enhance POMC transcription, cell proliferation, and tumor growth. Epigenetic changes through micro RNAs and decreased DNA deacetylation by histone deacetylase type 2 (HDAC2), may also affect tumor growth. All the former mechanisms may become interesting therapeutic targets for CTs, aside from temozolomide, currently used for aggressive tumors. Potential therapeutic agents are EGFR inhibitors such as gefitinib and lapatinib, the purine analog R-roscovitine by dissociation of CDK2/Cyclin E complex, the HSP90 inhibitor silibinin (novobiocin), to reduce resistance to glucocorticoid-mediated negative feedback, and BRAF inhibitors vemurafenib and dabrafenib in BRAF V600E positive tumors. This review summarizes the molecular mechanisms related to CTs tumorigenesis, their diagnostic approach, and provides an update of the potential novel therapies, from the lab bench to the clinical translation.

Cystic appearance on magnetic resonance imaging in bihormonal growth hormone and prolactin tumors in acromegaly

PURPOSE

To investigate demographic, imaging and laboratory characteristics, and treatment outcomes of acromegaly patients who have bihormonal (BA) growth hormone (GH) and prolactin (PRL) immunoreactive adenomas compared to patients who have densely granulated GH adenomas (DGA) and sparsely granulated GH adenomas (SGA).

METHODS

Retrospective review of single-center surgically treated acromegaly patients; pathology was analyzed by a single neuropathologist using 2017 WHO criteria. Preoperative magnetic resonance imaging was assessed to evaluate tumor size, cystic component, invasion and T2 signal intensity.

RESULTS

Seventy-seven patients; 19 BA (9 mammosomatotroph and 10 mixed GH and PRL adenomas) were compared with 30 DGA, and 28 SGA. Patients with BA were older than SGA (49.6 vs 38.5 years, p = 0.035), had a higher IGF-1 index (3.3 vs 2.3, p = 0.040) and tumors were less frequently invasive (15.8% vs 57.1%, p = 0.005). BA more frequently had a cystic component on MRI than both SGA and DGA (52.6% vs 14.3%, and 22%, p = 0.005 and 0.033, respectively). When all histological types were combined, biochemical remission postoperatively was more common in non-cystic than cystic tumors (50% vs 22.5%, p = 0.042). Somatostatin receptor ligand response rate was 66.7%, 90.9% and 37.5% in BA, DGA and SGA patients, respectively (p = 0.053).

CONCLUSION

Imaging characteristics are an increasingly important adenoma behavior determinant. An adenoma cystic component may suggest that a GH adenoma is a BA. Cystic tumors exhibited lower rates of surgical remission in this series; therefore, optimized individual patient treatment is needed, as patients could be candidates for primary medical treatment.

Distinct Pattern of Endoplasmic Reticulum Protein Processing and Extracellular Matrix Proteins in Functioning and Silent Corticotroph Pituitary Adenomas

Simple Summary

Corticotroph pituitary adenomas present a spectrum of functionality regarding hormonal production, ranging from functioning to silent tumors. Moreover, they show different invasiveness and recurrent behavior profiles, the silent being considered an aggressive type of adenomas. Through analyses of global transcriptome and proteome, we show that both groups expressed genes and protein related to protein synthesis and vesicular transport, and present a distinct pattern of collagen/ extracellular matrix proteins. Endoplasmic reticulum protein processing is a key factor for hormone production in functioning corticotroph adenomas. Furthermore, a distinct cell adhesion profile in silent corticotroph adenomas may explain the aggressive behavior. Together, our findings shed light on the different repertoires of activated signaling pathways in corticotroph pituitary adenomas and may reveal new potential medical targets.

Abstract

Functioning (FCA) and silent corticotroph (SCA) pituitary adenomas act differently from a clinical perspective, despite both subtypes showing positive TBX19 (TPIT) and/or adrenocorticotropic hormone (ACTH) staining by immunohistochemistry. They are challenging to treat, the former due to functional ACTH production and consequently hypercortisolemia, and the latter due to invasive and recurrent behavior. Moreover, the molecular mechanisms behind their distinct behavior are not clear. We investigated global transcriptome and proteome changes in order to identify signaling pathways that can explain FCA and SCA differences (e.g., hormone production vs. aggressive growth). In the transcriptomic study, cluster analyses of differentially expressed genes revealed two distinct groups in accordance with clinical and histological classification. However, in the proteomic study, a greater degree of heterogeneity within the SCA group was found. Genes and proteins related to protein synthesis and vesicular transport were expressed by both adenoma groups, although different types and a distinct pattern of collagen/extracellular matrix proteins were presented by each group. Moreover, several genes related to endoplasmic reticulum protein processing were overexpressed in the FCA group. Together, our findings shed light on the different repertoires of activated signaling pathways in corticotroph adenomas, namely, the increased protein processing capacity of FCA and a specific pattern of adhesion molecules that may play a role in the aggressiveness of SCA.

RECURRENT PITUITARY APOPLEXY IN AN ADENOMA WITH SWITCHING PHENOTYPES

Objective

To describe an unusual presentation of a patient with recurrent pituitary apoplexy of an adenoma that switched phenotypes from a nonfunctioning, or silent gonadotroph adenoma (SGA), to a silent corticotroph adenoma (SCA). We discuss the potential etiologies of both recurrent pituitary apoplexy and phenotype switching of pituitary tumors.

Methods

The presented case includes clinical and biochemical findings, surgical outcomes, and pathologic reports related to the treatment of our patient who presented with recurrent pituitary apoplexy.

Results

A 56-year-old man presented for evaluation of decreased libido and was found to have a low testosterone level. A pituitary magnetic resonance image demonstrated an 8-mm pituitary adenoma. He underwent transsphenoidal surgery (TSS) to remove the tumor and pathology demonstrated an SGA immunopositive for luteinizing hormone and follicle-stimulating hormone with evidence of apoplexy. Eight years later, the patient underwent another TSS after developing acute-onset headache, vomiting, and a cranial nerve palsy. Pathology at this time showed a necrotic tumor consistent with apoplexy with negative immunostains for all pituitary tumors. Three years after this, the tumor recurred and after another TSS the tumor stained positive for adrenocorticotropic hormone but was negative for luteinizing hormone and follicle-stimulating hormone with hemorrhage consistent with apoplexy. A few years afterward, he again developed acute-onset headache and cranial nerve palsies and had another TSS. On pathology, the tumor demonstrated extensive necrosis consistent with apoplexy and again stained positive for adrenocorticotropic hormone. The patient was then referred for radiation therapy and was subsequently lost to follow up.

Conclusion

Recurrent pituitary apoplexy in the same patient has only been described 3 times in the literature. There have been no case reports of a pituitary adenoma that switched phenotypes from an SGA to SCA. We suggest that pituitary apoplexy may recur multiple times due to a tumor with particularly fragile vessel walls and increased vascularization. We review the literature that suggests clinical and molecular similarities between SGAs and SCAs. Further studies are needed to determine the etiologies of recurrent apoplexy and pituitary adenomas with switching phenotypes.

How to Classify the Pituitary Neuroendocrine Tumors (PitNET)s in 2020

Adenohypophyseal tumors, which were recently renamed pituitary neuroendocrine tumors (PitNET), are mostly benign, but may present various behaviors: invasive, “aggressive” and malignant with metastases. They are classified into seven morphofunctional types and three lineages: lactotroph, somatotroph and thyrotroph (PIT1 lineage), corticotroph (TPIT lineage) or gonadotroph (SF1 lineage), null cell or immunonegative tumor and plurihormonal tumors. The WHO 2017 classification suggested that subtypes, such as male lactotroph, silent corticotroph and Crooke cell, sparsely granulated somatotroph, and silent plurihormonal PIT1 positive tumors, should be considered as “high risk” tumors. However, the prognostic impact of these subtypes and of each morphologic type remains controversial. In contrast, the French five-tiered classification, taking into account the invasion, the immuno-histochemical (IHC) type, and the proliferative markers (Ki-67 index, mitotic count, p53 positivity), has a prognostic value validated by statistical analysis in 4 independent cohorts. A standardized report for the diagnosis of pituitary tumors, integrating all these parameters, has been proposed by the European Pituitary Pathology Group (EPPG). In 2020, the pituitary pathologist must be considered as a member of the multidisciplinary pituitary team. The pathological diagnosis may help the clinician to adapt the post-operative management, including appropriate follow-up and early recognition and treatment of potentially aggressive forms.

Clinical, Laboratory, and Treatment Profiles of Silent Corticotroph Adenomas That Have Transformed to the Functional Type: A Case Series With a Literature Review

Purpose: Silent corticotroph adenoma (SCA) is clinically non-functional pituitary adenoma with expression of corticotropin or Tpit. To further understand the characteristics of this rare type of SCA transforming to a functional SCA, we retrospectively reviewed SCAs that converted to typical Cushing's syndrome at a tertiary medical center and the relevant literature. Methods: Patients were identified based on the diagnosis of pituitary adenoma without symptoms of hypercortisolism at the initial visit with positive Immunohistochemical (IHC) staining for corticotropin or Tpit after surgery and subsequent transformation to functional SCAs during the follow-up period from March 1990 to January 2020 at Peking Union Medical College Hospital and in the literature. The characteristics of the clinical manifestations, biochemical results, imaging findings, pathology findings and outcome were analyzed. Results: Altogether, 16 patients were included in the study with an average age of 42.0 ± 12.48 (18-65) years at the first visit. Females were slightly predominant (F:M = 1.3:1). The median time of conversion from the nonfunctional to the functional type was 30 (13.0, 68.3) months. Once a functional SCA developed, the adrenocorticotropic hormone (ACTH) level and 24-h urine free cortisol were increased 3.8- (2.6, 12.9) and 5.3- (2.6, 19.3) fold, respectively, above the normal range. Approximately 50% of the patients had macrocystic changes on pituitary MRI. All 16 patients experienced 1-5 surgeries with a median of 2.5 (2.0, 4.0) surgeries. The proportion of patients with Ki-67 ≥ 3% increased from 22.2% (2/9) at the beginning to 50% (7/14) at the time of functional SCA diagnosis. Thirteen patients received radiotherapy, and 4 patients (30.8%) achieved remission. Four patients with refractory functional SCAs received temozolomide treatment with the normalization of cortisol in 4 cases and reduced tumor volume in 3 cases. Conclusion: In this study, all cases that transformed to functional SCAs were macroadenomas. Hypercortisolism was more severe in functional SCA patients. The tumors tended to have frequent recurrence and were highly invasive. Temozolomide could be a promising treatment for refractory functional SCA cases. Long-term follow-up is needed for nonfunctional SCAs since some cases have the potential to transform to clinical Cushing's syndrome.

Predicting early post-operative remission in pituitary adenomas: evaluation of the modified knosp classification

PURPOSE

Cavernous sinus invasion by pituitary adenomas is an important prognostic factor for evaluating the possibilities of complete remission and to guide patient management. A widely used Magnetic Resonance Imaging grading system, suggested by Knosp in 1993, has recently been revised by the same group. The aims of our study were to apply this revised grading system to our surgical series, to determine its association with surgical outcomes, gross-total resection (GTR) and endocrinological remission (ER), paying particular attention to grades 3A and 3B, which represent the novelty of this revised classification.

METHODS

We included consecutive patients who underwent endoscopic endonasal surgery for a macroadenoma from September 2012 to December 2016. MRI images were reviewed and classified according to the revised Knosp classification. Surgical reports indicated the intra-operative CS invasion. GTR and ER were evaluated on 3-months post-operative MRI and endocrine evaluation.

RESULTS

254 patients were included in this study. We found a total rate of cavernous sinus invasion of 18.4%. Different outcomes were observed for each grade, with an increased rate of cavernous sinus invasion with each grade. Per-operative rates of invasion were 61.5 and 78.6% in grades 3A and 3B respectively. GTR was negatively correlated with the grade, while rates were 55.8% and 30.0% for grades 3A and 3B respectively.

CONCLUSION

The revised Knosp radiological classification contributes to the prediction of surgical outcomes and early ER in pituitary adenomas. To manage, as precisely as possible, the risk of early recurrence in pituitary adenomas, clinicians should also consider other recognized prognostic factors, such as the proliferative status of the tumor.

Non-functioning pituitary macroadenoma: surgical outcomes, tumor regrowth, and alterations in pituitary function-3-year experience from the Iranian Pituitary Tumor Registry

PURPOSE

The aim of this study was to assess clinical features and therapeutic outcomes in patients with clinically non-functioning pituitary macroadenomas (NFPMAs).

METHOD

This is a retrospective cohort study of NFPMA patients treated surgically and followed periodically between 2015 and 2017 in a tertiary care center in Iran. Descriptive analysis was performed applying appropriate tests. Binary logistic regression models were used to determine the predictive factors for subtotal tumor resection (STR) and hormonal recovery. Data were analyzed by Stata software.

RESULT

A total of 71 patients with a mean age of 50.6 ± 1.4 years were studied. The mean diameter of the adenoma was 26.8 ± 1.1 mm. The most frequent symptoms were headache (85.75%), visual field defect (VFD) (78.3%), and hypogonadal symptoms (40.3%). Gross total resection (GTR) was achieved in 45.1%. Preoperative hypopituitarism was observed in 50.7% of patients. Recovery of at least one axis occurred in 36.1% of the patients suffering from hypopituitarism preoperatively, while new-onset postoperative hormonal deficiency appeared in 14.3% of patients. Multivariate analyses showing preoperative tumor size (OR = 38.2; P = 0.008) and cavernous sinus extension (OR = 13.4; P = 0.020) were predictors of STR. Moreover, hormonal recovery was observed not to be related to age, gender, tumor size, or the extent of tumor resection.

CONCLUSIONS

Tumor size and cavernous sinus extension are the main predictors for STR. Notably, recovery of the gonadal axis in a large proportion of patients supports the surgical resection of NFPAM in patients suffering from gonadal deficiency, even in the absence of VFD.

Functioning Pituitary Adenomas - Current Treatment Options and Emerging Medical Therapies

Pituitary adenomas are benign tumours comprising approximately 16% of all primary cranial neoplasms. Functioning pituitary adenomas (prolactinomas, somatotroph, corticotroph, thyrotroph and rarely gonadotroph adenomas) cause complex clinical syndromes and require prompt treatment to reduce associated morbidity and mortality. Treatment approaches include transsphenoidal surgery, medical therapy and radiation. Medical therapy is the primary therapy for prolactinomas, and surgery by a skilled neurosurgeon is the first-line approach for other functioning pituitary adenomas. A multimodal treatment is frequently necessary to achieve biochemical and clinical control, especially, when surgery is not curative or when medical therapy fails. Several emerging, novel, medical treatments for acromegaly, Cushing's disease and prolactinomas are in phase II and III clinical trials and may become effective additions to the current drug armamentarium. The availability of various management options will allow an individualised treatment approach based on the unique tumour type, clinical situation and patient preference.

High prevalence of adrenal insufficiency at diagnosis and headache recovery in surgically resected Rathke's cleft cysts-a large retrospective single center study

BACKGROUND

Rathke's cleft cysts (RCC) are lesions that arise from Rathke's pouch. Though frequently incidental, resulting symptoms in a minority of cases are indicators for surgical resection, which may prove beneficial.

OBJECTIVE

To characterize a cohort of surgically-resected RCC cases at Oregon Health & Science University; tabulate associated hormonal imbalances and symptoms, possible symptom reversal with surgery, determine recurrence risk; identify predictors of recurrence and headache improvement.

METHOD

Electronic records of all RCC resected cases (from 2006-2016; 11 years) were retrospectively reviewed. Patients had been evaluated by one neuroendocrinologist using a uniform protocol.

RESULTS

A pathological RCC diagnosis was established in 73 of 814 (9%) surgical pituitary cases. The RCC cohort was 77% (n = 56/73) female, mean age was 39.5 ± 14.9 years at first surgery, and at presentation headache was reported in 88% and visual defects/diplopia in 18% of patients. Initial RCC maximum diameter was 1.3 ± 0.7 cm. The most frequent hormonal deficit was cortisol; 24% of patients had a new adrenal insufficiency (AI) diagnosis, however, 36% also had AI at 3 months post-operatively. Mean follow up was 4.0 ± 4.5 years. Two-thirds of patients (41/62) had headache improvement 3 months post-operatively. Post-operative imaging revealed no residual cyst in 58% (38/65). In those patients with no residual RCC, 29% had recurrence and 71% had long lasting cure. From the 42% (27/65) of patients with residual cyst on post-operative imaging; 59% (16/27) remained stable, 26% (7/27) progressed and 15% (4/27) regressed.

CONCLUSION

Symptomatic RCC present mostly in women, with a high proportion reporting headaches. Prevalence of AI at diagnosis is high. Surgery may not achieve adrenal axis recovery, but renders a high percentage of headache improvement. Approximately 25% of RCC will recur by 4 years postoperatively. Clinicians should cautiously screen patients with symptomatic RCC, regardless of lesion size for AI.

[Morphofunctional features of non-functioning pituitary adenomas]

Non-functioning pituitary adenomas (NFPAs) account for about 30% of all pituitary tumors. NFPAs are characterized by the lack of secretory potential or its weak expression insufficient for determination of the blood level of adenohypophyseal tropic hormones and for development of a specific clinical picture. Morphologically, NFPAs are a heterogeneous group of tumors, the classification of which was previously based only on immunoreactivity for pituitary tropic hormones. The WHO revised its Classification of Tumors of Endocrine Organs (4th edition) in 2017. The main changes relate to adenohypophysial-cell lineage for the designation of adenomas into subtypes. The introduction of transcription factor antibodies has become a fundamentally new approach to the classification of NFPAs, which is necessary to recognize less differentiated tumor types. This paper provides information on the new histopathological classification of pituitary adenomas, on the theories of silent adenomas, and on the proliferative and prognostic markers of NFPAs.

Clinical outcomes in male patients with lactotroph adenomas who required pituitary surgery: a retrospective single center study

PURPOSE

Lactotroph adenomas (LA) are the most frequently encountered pituitary tumors. Although more frequently observed in women, LAs in men were recently included in a more aggressive category regardless of histological grading, by the WHO. We aimed to perform a rigorous retrospective review of a single center's pre-operative evaluation, patient characteristics and outcomes of male LAs patients requiring pituitary surgery.

METHODS

A retrospective review, over 11 years, of patients who underwent resection of a pituitary adenoma at a single center was conducted. Predictors of persistent disease in male LAs patients along with a comparison to predictors of silent corticotroph adenomas (SCAs) patients who also underwent surgery at the center was also conducted.

RESULTS

Thirty-one male patients with LAs were identified. When compared to SCAs patients, LAs male patients were younger (41 vs. 50 years of age, p = 0.01). Men with LAs had more invasive tumors (75% vs. 44.7% p = 0.02). More LAs in men had residual tumor after surgery than patients with SCA (92.6% vs. 42.1%, p < 0.001). Male patients with LAs and patients with SCA had similar rates of requiring additional surgery (28.9% vs. 24.1%, p = NS) and radiation therapy (18.4% vs. 19.4%, p = NS).

CONCLUSIONS

High rates of DA resistance, invasive tumors and postoperative residual disease in male patients with LA who required surgery are shown. Surgery improved optic chiasm compression, PRL level and central hypogonadism but, not surprisingly, failed to normalize other pituitary hormones and/or eliminate need for DA therapy.

Nonfunctioning Pituitary Adenoma Recurrence and Its Relationship with Sex, Size, and Hormonal Immunohistochemical Profile

BACKGROUND

Tumor recurrence or incomplete resection in nonfunctioning pituitary adenomas (NFPAs) is relatively common. However, predictive factors of tumor recurrence in NFPAs are not well established. We evaluated possible factors related to tumor recurrence in a large cohort of NFPAs at a single pituitary neurosurgery center.

METHODS

A retrospective analysis was conducted of 410 medical records of patients with NFPAs treated by transsphenoidal surgery between 2000 and 2014.

RESULTS

Among the participants, 210 were female (51.0%). A total of 14.1% had giant adenomas. Null-cell pituitary adenomas (n = 239; 58.9%) were the most frequent, followed by silent gonadotroph adenomas (n = 112; 27.3%). Null-cell adenomas were more frequent in women (P = 0.008) and silent gonadotroph adenomas were more frequent in men (P = 0.004). Recurrence was not related to sex or age. Tumor recurrence occurred more often among silent corticotropic adenomas and giant adenomas (hazard ratio 2.45; P < 0.0001 and hazard ratio 2.35; P = 0.001, respectively). Silent thyrotrophic adenoma presented a comparable frequency of recurrence of silent corticotropic adenomas, despite having borderline significance (P = 0.07).

CONCLUSIONS

NFPA tumors have a high heterogeneous hormonal profile and may have prognostic importance. Silent corticotropic adenomas and giant adenomas present a high rate of recurrence.

Recurrent non-functioning pituitary adenomas: a review on the new pathological classification, management guidelines and treatment options

At least 50% of surgically resected non-functioning pituitary adenomas (NFPA) recur. Either early or late adjuvant radiotherapy is highly efficacious in controlling recurrent NFPA but associates potentially burdensome complications like hypopituitarism, vascular complications or secondary neoplasm. Reoperation is indicated in bulky tumor rests compressing the optic pathway. To date, no standardized medical therapy is available for recurrent NFPA although cabergoline and temozolomide show promising results. Guidelines on the management of recurrent NFPAs are now available. The new 2017 WHO pituitary tumor classification, based on immunohistochemistry and transcription factor assessment, identifies a group of aggressive NFPA variants that may benefit from earlier adjuvant therapy. Nevertheless, NFPA patients exhibit a reduced overall life expectancy largely due to hypopituitarism and treatment-related morbidity. The management of recurrent NFPA benefits from a multidisciplinary teamwork of surgeons, endocrinologists, radiation oncologists, ophthalmologists, pathologists and neuro-radiologists in order to provide individualized therapy and anticipate deterioration.

Prognostic factors of regrowth in nonfunctioning pituitary tumors

Surgery is the treatment of choice for nonfunctioning pituitary tumors (NFPTs). Postoperative tumor regrowth during follow-up is present in about half of the patients with invasive NFPTs with residual tumor but occurs also in 15% of patient without residue. Therapeutic strategies should consider this risk of recurrence and the potential side effects associated with therapeutic options. Identification of prognostic markers is mandatory to help clinicians to predict the risk of recurrence and to choose the best strategy between conservative follow-up, second surgery, postoperative adjuvant radiation therapy, and medical treatment (dopamine agonists, somatostatin analogs). Recent advances in pathological classification may be the first step for identification of NFPTs with a high risk of recurrence.