Histopathology of growth hormone-secreting pituitary tumors: State of the art and new perspectives.

Somatotroph (GH) adenomas/PitNETs typically arise from adenohypophysis and are biochemically active, leading to acromegaly and gigantism. More rarely, they present with ectopic origin and do not present overt biochemical or clinical features (silent variants). Histopathological examination should consider the clinical and radiological background, and include multiple steps assessing tumor morphology, pituitary transcription factors (PTFs), hormone secretion, proliferation markers, granulation, and somatostatin receptors (STRs), aimed at depicting as better as possible tumor origin (in case of non-functioning and/or metastatic tumor), and clinical behavior, including response to treatment. GH-secreting tumors are part of the Pit-1 family tumors and can secrete GH only (pure somatotrophs) or co-secrete prolactin (mixed tumors; in this case, various histological subtypes have been identified). Each subtype presents unique radiological, biochemical, and clinical characteristic. Therefore, the integration of biochemical, clinical, radiological, and histopathological elements is fundamental for proper diagnosis and management of pituitary adenomas/PitNETs, to be performed in referral Centers. In more recent times, the importance of genetic and epigenetic evaluation in the characterization of pituitary tumors (i.e., early identification of aggressive variants) has been outlined by some large studies, with the intention of improving targeted treatments.

Immunological signatures and predictive biomarkers for first-generation somatostatin receptor ligand resistance in Acromegaly.

PURPOSE: Predicting resistance to first-generation Somatostatin Receptor Ligands (fg-SRL) in Acromegaly patients remains an ongong challenge. Tumor-associated immune components participate in various pathological processes, including drug-resistance. We aimed to identify the immune components involved in resistance of fg-SRL, and to investigate biomarkers that can be targeted to treat those drug-resistant Acromegaly. METHODS: We conducted a retrospective study involving 35 Acromegaly patients with somatotropinomas treated postoperatively with fg-SRL. Gathering clinicopathological data, SSTR2 expression, and immunological profiles, we utilized univariate, binary logistic regression, and ROC analyses to assess their predictive roles in fg-SRL resistance. Spearman correlation analysis further examined interactions among interested characteristics. RESULTS: 19 patients (54.29%) exhibited resistance to postoperative fg-SRL. GH level at diagnosis, preoperative tumor volume, T2WI-MRI intensity, granularity, PD-L1, SSTR2, and CD8 + T cell infiltration showed association with clinical outcomes of fg-SRL. Notably, T2WI-MRI hyperintensity, PD-L1-IRS > 7, CD8 + T cell infiltration < 14.8/HPF, and SSTR2-IRS < 5.4 emerged as reliable predictors for fg-SRL resistance. Correlation analysis highlighted a negative relationship between PD-L1 expression and CD8 + T cell infiltration, while showcasing a positive correlation with preoperative tumor volume of somatotropinomas. Additionally, 5 patients with fg-SRL resistance underwent re-operation were involved. Following fg-SRL treatment, significant increases in PD-L1 and SSTR5 expression were observed, while SSTR2 expression decreased in somatotropinoma. CONCLUSION: PD-L1 expression and CD8 + T cell infiltration, either independently or combined with SSTR2 expression and T2WI-MRI intensity, could form a predictive model guiding clinical decisions on fg-SRL employment. Furthermore, targeting PD-L1 through immunotherapy and embracing second-generations of SRL with higher affinity to SSTR5 represent promising strategies to tackle fg-SRL resistance in somatotropinomas.

Clinical Characteristics and Management of Cosecreting Thyroid Stimulating Hormone or Prolactin Pituitary Growth Hormone Adenomas: A Case-Control Study.

OBJECTIVE: Cosecreting thyroid stimulating hormone (TSH) or prolactin (PRL) in patients with pituitary growth hormone (GH) adenomas has been rarely reported. Our study aimed to elucidate their clinical characteristics. METHODS: We retrospectively collected data of 22 cases of cosecreting GH and TSH pituitary adenomas [(GH+TSH)oma] and 10 cases of cosecreting GH and PRL pituitary adenomas [(GH+PRL)oma] from Beijing Tiantan Hospital, Capital Medical University between January 2009 and January 2023. The clinical manifestation, preoperative hormone levels, imaging features, pathologic characteristics, and biochemical remission rates were compared among 335 patients with solo-secreting GH adenomas (GHoma) and 49 patients with solo-secreting TSH adenoma (TSHoma). Patients with (GH+TSH)oma and (GH+PRL)oma were grouped according to biochemical remission to explore the risk factors leading to biochemical nonremission. RESULTS: Cosecreting pituitary GH adenomas had various clinical manifestations and a larger tumor volume and were more likely to invade the cavernous sinus bilaterally and compress the optic chiasm. GH and TSH levels were lower in (GH+TSH)oma than in GHoma or TSHoma. Solo part remission was observed both in (GH+TSH)oma and (GH+PRL)oma. Cavernous sinus invasion was an independent risk factor for biochemical nonremission in patients with (GH+TSH)oma and (GH+PRL)oma. CONCLUSIONS: The clinical manifestation of (GH+TSH)oma and (GH+PRL)oma may be atypical. When screening for pituitary adenomas, a comprehensive evaluation of all pituitary target gland hormones is needed. Cosecreting pituitary GH adenomas are more aggressive and surgery is often unable to completely remove the tumor, requiring pharmacologic or radiological treatment if necessary. Clinicians should give high priority to biochemical remission, although solo part remission may occur.

Clinicopathological Analysis of Densely and Sparsely Granulated Somatotroph Tumors of Pituitary.

OBJECTIVE: Somatotroph tumors are the second most common type of pituitary neuroendocrine tumors, which can be further classified into 2 subtypes-densely granulated somatotroph tumors (DGSTs) and sparsely granulated somatotroph tumors (SGSTs). The aim of this study was to investigate the clinical significance of the 2 subtypes in a retrospective analysis. METHODS: From the database of the Ningbo Clinical Pathology Diagnosis Center, we collected patients diagnosed with pituitary somatotroph tumors. We then compiled pertinent clinical and radiological data and proceeded with histopathological examination involving hematoxylin-eosin staining and immunohistochemical staining. Subsequent analysis compared the 2 subtypes using either χ2 test or Fisher exact test. RESULTS: We analyzed 40 cases of somatotroph tumors, 18 cases DGSTs and 22 SGSTs. Male-to-female ratio was 5:4 for DGSTs and 4:7 for SGSTs. Mean age was 52.83 years for DGSTs and 47.18 years for SGSTs. Statistically significant differences were observed between the DGST and SGST groups in invasiveness (P = 0.0267) and postoperative remission (P = 0.007). Cells of both DGSTs and SGSTs exhibited coexpression of PIT1, growth hormone, and CAM5.2, although the patterns of CAM5.2 expression differed between the 2 subtypes. CONCLUSIONS: The efficacy of CAM5.2 staining in distinguishing between DGSTs and SGSTs was demonstrated. SGSTs, with their increased invasiveness and lower remission rate, are a high-risk subtype. The histological subtype of somatotroph tumors plays a crucial role in guiding treatment decisions and prognostic evaluation in affected patients.

DNA Methylation Pattern in Somatotroph Pituitary Neuroendocrine Tumors.

INTRODUCTION: Growth hormone secretion by sporadic somatotroph neuroendocrine pituitary tumors (PitNETs) is a major cause of acromegaly. These tumors are relatively heterogenous in terms of histopathological and molecular features. Our previous transcriptomic profiling of somatotroph tumors revealed three distinct molecular subtypes. This study aimed to investigate the difference in DNA methylation patterns in subtypes of somatotroph PitNETs and its role in distinctive gene expression. METHODS: Genome-wide DNA methylation was investigated in 48 somatotroph PitNETs with EPIC microarrays. Gene expression was assessed with RNAseq. Bisulfite pyrosequencing and qRT-PCR were used for verifying the results of DNA methylation and gene expression. RESULTS: Clustering tumor samples based on methylation data reflected the transcriptome-related classification. Subtype 1 tumors are densely granulated without GNAS mutation, characterized by high expression of NR5A1 (SF-1) and GIPR. The expression of both genes is correlated with specific methylation of the gene body and promoter. This subtype has a lower methylation level of 5' gene regions and CpG islands than the remaining tumors. Subtype 2 PitNETs are densely granulated and frequently GNAS-mutated, while those in subtype 3 are mainly sparsely granulated. Methylation/expression analysis indicates that ∼50% genes located in differentially methylated regions are those differentially expressed between tumor subtypes. Correlation analysis revealed DNA methylation-controlled genes, including CDKN1B, CCND2, EBF3, CDH4, CDH12, MGMT, STAT5A, PLXND1, PTPRE, and MMP16, and genes encoding ion channels and semaphorins. CONCLUSION: DNA methylation profiling confirmed the existence of three molecular subtypes of somatotroph PitNETs. High expression of NR5A1 and GIPR in subtype 1 tumors is correlated with specific methylation of both genes.

Analysis of Diffusion-Weighted and T2-Weighted Imaging in the Prediction of Distinct Granulation Patterns of Somatotroph Adenomas.

OBJECTIVE: The heterogeneity of the somatotroph adenomas, especially for sparsely granulated (SG) and densely granulated (DG) subtypes, has attracted great attention in identifying their imaging biomarker. The purpose of the current study was to compare the diagnostic performance of diffusion-weighted and T2-weighted magnetic resonance imaging (MRI) sequences for preoperatively distinguishing the granulation patterns of somatotroph adenomas. METHODS: Thirty-two patients with a clinical diagnosis of somatotroph adenomas from October 2018 to March 2023 were included in this study. Coronal diffusion-weighted imaging (DWI) and T2-weighted MRI sequence data were collected from 3.0T MRI and compared between SG and DG groups. The immunohistochemistry was used to confirm the electron microscopy pathologic subtypes and Ki67 expression levels of somatotroph adenomas postoperatively. RESULTS: Patients in the SG group had significantly higher signal intensity (SI) ratio of DWI (rDWI) (P < 0.001), lower SI ratio of apparent diffusion coefficient (rADC) (P < 0.001), and higher SI ratio of T2-weighted imaging (P = 0.011). The combined diagnosis index of rDWI and rADC had the highest diagnostic efficiency in predicting SG adenomas (sensitivity, 93.3%; specificity, 88.2%; P < 0.001). The rDWI and rADC values had positive and negative correlations with the Ki67 index and tumor maximum diameter, respectively. Lower rADC×103 was an independent predictor for SG adenomas. CONCLUSIONS: Our results indicated that compared with previously used T2-weighted imaging, the DWI sequence, especially the combined diagnosis index of rDWI and rADC, could more efficiently distinguish the granulation patterns of somatotroph adenomas preoperatively.

A Novel Preoperative Score to Predict Long-Term Biochemical Remission in Patients with Growth-Hormone Secreting Pituitary Adenomas.

OBJECTIVE: Transsphenoidal surgery (TSS) is considered the treatment of choice in most patients with growth hormone (GH)-secreting pituitary adenomas. Several preoperative factors have been studied to predict postsurgical remission. Our objective was to design a score that could be used in the preoperative setting to identify patients that will achieve long-term biochemical remission after TSS. METHODS: A retrospective analysis of consecutive patients with GH-secreting pituitary adenomas that underwent TSS in our institution from 2000 to 2015 who fulfilled prespecified criteria were included. Logistic regression methods were used to evaluate independent preoperative variables predicting long-term remission. Beta coefficients were used to create a scoring system for clinical practice. RESULTS: Sixty-eight patients were included, with a mean follow-up time of 87 months. Twenty (29%) patients had tumors with a Knosp grade ≥ 3A. Gross-total resection was achieved in 43 (63%) patients. Thirty-three (48%) patients had long-term biochemical remission after TSS. In a multivariate analysis, the following variables were statistically significantly associated with long-term biochemical remission: age, adenoma size (diameter), Knosp grade, GH level, and insulin growth-factor 1index 1 at diagnosis. A score of <3 out of 8 total points was identified as a cutoff associated with long-term remission, with a sensitivity of 91.4% and specificity of 72.7% (AUC 0.867, OR 28.44, 95% CI 6.94-116.47, P = < 0.001). CONCLUSIONS: A novel, simple, easy-to-use scoring system was created to identify patients with the highest chances of long-term biochemical remission following TSS. This scale should be prospectively validated in a multicenter study before widespread adoption.

Prospective Integrated Individualized Clinical Decision-making and Outcome Evaluation for Surgery in Patients with Acromegaly: A New Paradigm?

BACKGROUND: Growth-hormone-producing pituitary adenomas have variable likelihood for biochemical remission (BR). During preoperative counseling, individual estimated surgical likelihoods/risks should be balanced against alternative (medical) treatments, which is necessary for accurate outcome presentation. Preoperative estimation of BR or total resection (TR) likelihoods have not been reported, resulting in extrapolation of individual outcomes. AIMS: To share an innovative outcome reporting paradigm by integrating surgical decision-making, and expected/realized results, resulting from the Value-Based Health Care (VBHC) care path with periodical performance evaluation and care innovation cycle. METHODS: Prospective cohort study of consecutive patients with acromegaly undergoing surgery (January 2016-December 2020; postoperative follow-up ≥6 months) reporting on both classic, and novel innovative outcome evaluations. RESULTS: Fifty eight patients (66 procedures) were included. Intended TR was achieved in 34/50 procedures, whereas intended debulking was achieved in 15/16 procedures. 38/66 procedures resulted in BR, and 4 procedures resulted in permanent complications. Achieving intended surgical goal was estimated preoperatively as likely in 33 (goal achieved (GA) in 28/33), potentially in 27 (GA in 19/27), and unlikely in 6 procedures (GA in 2/6). Integrated Outcome Square 1 (IOQ1) -intended effect achieved without complications- was achieved in 46/66 patients. CONCLUSION: Implementation of the developed quality process positively affects preoperative individual shared decision-making, resulting in improved (individual) outcomes, particularly in complex patients for whom preoperative chances are not fully reflected by tumor size and KNOSP grade, e.g., reoperations, or other challenging circumstances identified during preoperative counseling. Through repeated evaluations, our own team's knowledge increased, allowing for improved individualized treatment strategies.

Clinical characteristics and therapeutic outcomes of acromegalic patients with giant growth hormone-secreting pituitary adenomas: a single-center study of 67 cases.

PURPOSE: Acromegalic patients with giant growth hormone-secreting pituitary adenomas (GHPAs) (≥ 40 mm) are relatively rare, and their clinical characteristics and treatment outcome data are limited. This study aims to analyze the clinical practice experience of giant GHPAs. METHODS: Sixty-seven acromegalic patients with giant GHPAs and 67 patients with macro GHPAs (10-39 mm), matched for age and gender from the same hospital during the same period, were retrospectively recruited. The clinical characteristics, treatment, and outcomes were analyzed. RESULTS: Enlargement of the extremities and facial features were the most common symptoms in most patients (92.5%). Compared with the macroadenoma group, more frequent visual impairment (86.6% vs. 25.4%, P < 0.001) and gonadal axis dysfunction (49.3% vs. 34.3%, P = 0.008), higher preoperative fasting GH, nadir GH after OGTT and IGF-1 levels, and a higher proportion of extrasellar tumor invasion were seen in the giant adenoma group. As the adenoma size increases, the total resection rate decreases, and postoperative complications and multimodal treatment strategies increase significantly. Fasting and nadir GH levels remained higher at 1 week postoperatively, and there were more surgical complications and cases of anterior hypopituitarism in the giant group. After a median follow-up of 36 months, 12 patients (36.4%) in the giant GHPA group and 17 (36.2%) in the macro GHPA group achieved biochemical remission. Other factors such as age of onset, age of diagnosis, delayed diagnosis time, metabolic complications, p53 positive rate, and Ki-67 index showed no significant difference between the two groups. CONCLUSIONS: With aggressive multimodal therapy, the biochemical remission rate of acromegalic patients with giant GHPAs is comparable to that of patients with macro adenoma. However, postoperative complications and hypopituitarism need to be closely monitored.

Clinical and prognostic significance of granulation patterns in somatotroph adenomas/tumors of the pituitary: a meta-analysis.

INTRODUCTION: Sparsely granulated somatotroph adenoma/tumor (SGST) is thought to be more clinically aggressive than densely granulated somatotroph adenoma/tumor (DGST). However, the literature is not entirely consistent as to the disparate demographic and behavioral features of these subtypes. In this study, we conducted a meta-analysis to further clarify the demographic, clinicopathological, prognostic, and molecular characteristics of SGST versus DGST. METHODS: We accessed two electronic databases to search for potential data. Pooled estimates of odds ratio (OR), mean difference (MD), and corresponding 95% confidence interval (CI) were calculated using the random-effect model. RESULTS: SGST was associated with younger patient age and lower male-to-female ratio (p < 0.001) compared to DGST. Clinically, SGST had larger tumor size and high rate of cavernous sinus and suprasellar extension (p < 0.001) than DGST. During postoperative follow-up, SGST was associated with a lower endocrinological remission rate (OR 0.60; 95% CI 0.40 to 0.90; p = 0.01) and a poorer response rate to SRL (OR 0.16; 95% CI 0.08-0.35; p < 0.001) in comparison to DGST. The prevalence of GSP mutations was significantly lower in SGST (OR 0.36; 95% CI 0.17 to 0.79; p = 0.01). CONCLUSION: SGST and DGST were demographically, clinicopathologically, and molecularly different from each other with the former associated with adverse treatment outcomes and poor response to medical therapy. There are still gaps in translational studies that could help us better understand the behavior of these tumors and identify potential targets in the treatment of sparsely granulated tumors.

Metabolomics in acromegaly: a systematic review.

The therapeutic response heterogeneity in acromegaly persists, despite the medical-surgical advances of recent years. Thus, personalized medicine implementation, which focuses on each patient, is justified. Metabolomics would decipher the molecular mechanisms underlying the therapeutic response heterogeneity. Identification of altered metabolic pathways would open new horizons in the therapeutic management of acromegaly. This research aimed to evaluate the metabolomic profile in acromegaly and metabolomics' contributions to understanding disease pathogenesis. A systematic review was carried out by querying four electronic databases and evaluating patients with acromegaly through metabolomic techniques. In all, 21 studies containing 362 patients were eligible. Choline, the ubiquitous metabolite identified in growth hormone (GH)-secreting pituitary adenomas (Pas) by in vivo magnetic resonance spectroscopy (MRS), negatively correlated with somatostatin receptors type 2 expression and positively correlated with magnetic resonance imaging T2 signal and Ki-67 index. Moreover, elevated choline and choline/creatine ratio differentiated between sparsely and densely granulated GH-secreting PAs. MRS detected low hepatic lipid content in active acromegaly, which increased after disease control. The panel of metabolites of acromegaly deciphered by mass spectrometry (MS)-based techniques mainly included amino acids (especially branched-chain amino acids and taurine), glyceric acid, and lipids. The most altered pathways in acromegaly were the metabolism of glucose (particularly the downregulation of the pentose phosphate pathway), linoleic acid, sphingolipids, glycerophospholipids, arginine/proline, and taurine/hypotaurine. Matrix-assisted laser desorption/ionization coupled with MS imaging confirmed the functional nature of GH-secreting PAs and accurately discriminated PAs from healthy pituitary tissue.

The Effect and Potential Mechanism Analysis of Growth Hormone-Secreting Pituitary Adenomas on Thyroid Function.

OBJECTIVE: Current studies on the effect of high growth hormone (GH)/insulin-like growth factor (IGF)-1 on thyroid function are inconsistent. The aim was to explore the effect and potential mechanism of high GH/IGF-1 on thyroid function by analyzing the changes of thyroid function in patients with growth hormone-secreting pituitary adenoma (GHPA). METHODS: This was a retrospective cross-sectional study. Demographic and clinical data of 351 patients with GHPA who were first admitted to Beijing Tiantan Hospital, Capital Medical University, from 2015 to 2022 were collected to analyze the relationship between high GH/IGF-1 levels and thyroid function. RESULTS: GH was negatively correlated with total thyroxine (TT4), free thyroxine (FT4), and thyroid-stimulating hormone (TSH). IGF-1 was positively correlated with total triiodothyronine (TT3), free triiodothyronine (FT3), and FT4 and negatively correlated with TSH. Insulin-like growth factor-binding protein (IGFBP)-3 was positively correlated with TT3, FT3, and FT3:FT4 ratio. The FT3, TT3, TSH, and FT3:FT4 ratio of patients with GHPA and diabetes mellitus (DM) were significantly lower than those with GHPA but without DM. With the increase of tumor volume, thyroid function gradually decreased. GH and IGF-1 were correlated negatively with age in patients with GHPA. CONCLUSION: The study emphasized the complex interaction between the GH and the thyroid axes in patients with GHPA and highlighted the potential effect of glycemic status and tumor volume on thyroid function.

AIP gene germline variants in adult Polish patients with apparently sporadic pituitary macroadenomas.

Introduction: Up to 5% of all pituitary tumors are hereditary e.g. due to MEN1 or aryl hydrocarbon receptor-interacting protein (AIP) genes mutations. Objectives: The study was aimed at the assessment of the frequency and characteristics of AIP-mutation related tumors in patients with apparently sporadic pituitary macroadenomas in the Polish population. Materials and methods: The study included 131 patients (57 males, 74 females; median age 42 years) diagnosed with pituitary macroadenomas, and with a negative family history of familial isolated pituitary adenoma (FIPA) or multiple endocrine neoplasia type 1 (MEN1) syndromes. Sanger sequencing was used for the assessment of AIP gene variants. The study was approved by the Ethics Board of JUMC. Results: AIP variants were identified in five of the 131 included subjects (3.8%): one diagnosed with Cushing's disease, two with acromegaly, and two with non-secreting adenomas. Patients harboring hereditary AIP gene alterations did not differ from the rest of the study group in median age at diagnosis (41.0 vs. 42.5 years, P=0.8), median largest tumor diameter (25 vs. 24 mm, P=0.6), gender distribution (60.0% vs. 56.3% females, P=0.8), secreting tumor frequency (60.0% vs. 67.5%, P=0.7), or acromegaly diagnosis frequency (40.0% vs.37.3%, P=0.9). Conclusions: In our series of apparently sporadic pituitary macroadenomas, AIP gene variant carriers did not differ substantially from patients with negative genetic testing. A risk factor-centred approach to AIP genetic screening may result in missing germline variants. Considering the clinical impact of such genetic variants and their relatively low penetrance, it is, however, doubtful if general genetic screening benefits the whole cohort of pituitary macroadenoma patients and their families.

Novel AIP mutation in exon 6 causing acromegaly in a German family.

The most frequent genetic alteration of familial isolated growth hormone producing pituitary neuroendocrine tumors is a germline mutation of the aryl hydrocarbon receptor-interacting protein (AIP) gene. Various AIP mutations are already known; however, an AIP mutation in exon 6 (c.811_812del; p.Arg271Glyfs*16) has not been reported yet. Here, we report a German family with two identical twins who were both affected by acromegaly and carried the above-mentioned novel AIP mutation. The father was found to be an unaffected carrier, while the paternal aunt most likely suffered from acromegaly as well and died from metastatic colorectal cancer. Apart from reporting a novel AIP mutation, this study does not only highlight the different clinical and histological features of the AIP mutated growth hormone producing pituitary neuroendocrine tumors but also confirms the poor responsiveness of dopamine agonists in AIP mutated acromegaly. Furthermore, it highlights the increased mortality risk of comorbidities typically associated with acromegaly.

Giant growth hormone-secreting pituitary adenomas from the endocrinologist's perspective.

OBJECTIVES: Since giant (≥40 mm) GH-secreting pituitary adenomas are rarely encountered, data on their characteristics and treatment outcomes are limited. We aimed to investigate the characteristics of giant GH-secreting pituitary adenomas and to compare their clinical, biochemical, imaging and histopathological features with non-giant macroadenomas. MATERIALS AND METHODS: We have evaluated 15 (six female/nine male) and 57 (29 female/28 male) patients with acromegaly in giant and <40 mm adenoma groups, respectively. Patients with <40 mm adenoma were further divided into subgroups with adenoma size 20-29 mm and 30-39 mm. RESULTS: In giant adenoma group, median (IQR) preoperative maximal diameter of adenoma was 40 mm (5 mm), median preoperative GH level was 40 (153.4) ng/mL and median baseline IGF-1 level was 2.19 (1.88) × ULN for age and sex. The number of surgeries was significantly higher in giant adenoma group (median 2, IQR 2) in which 66.7% of patients underwent repeated surgeries (p = 0.014). Residual tumor was detected after last operation in all patients with giant adenoma. Total number of treatment modalities administered postoperatively increased as adenoma size increased (p = 0.043). After a median follow-up duration of 10 years (IQR 10), hormonal remission was achieved in six patients (40%) of giant adenoma group, while the rate of hormonal remission in non-giant adenoma group was 37%. Although preoperative GH and IGF-1 levels and Ki-67 index tended to be higher with increasing adenoma size, there was no statistically significant difference between groups in terms of these variables, as well as age, sex and invasion status. CONCLUSION: Hormonal remission rates of acromegaly patients with ≥20 mm pituitary macroadenoma were comparable. However, giant GH-secreting pituitary adenomas require an aggressive multimodal treatment approach.

Predictors of postoperative biochemical remission in lower Knosp grade growth hormone-secreting pituitary adenomas: a large single center study.

PURPOSE: Growth hormone-secreting pituitary adenomas (GH-PAs) with a low Knosp grade are typically associated with a good postoperative biochemical remission (BR) rate. However, a proportion of patients do not achieve remission. In this study, we aimed to investigate predictive factors of postoperative remission for lower Knosp GH-PAs. METHODS: In this retrospective study, we enrolled 140 patients who were diagnosed with lower Knosp (0-2) GH-PAs and received trans-sphenoidal surgery between December 2016 and June 2021 from the largest pituitary tumor surgery center in southern China. The univariate, binary Logistic regression, and receiver operating characteristic curve (ROC) analyses were employed to determine independent predictors and cutoff values of remission. The postoperative outcome was defined as remission using the 2010 consensus criteria of acromegaly. RESULTS: One hundred and thirty six patients (97.1%) achieved gross total resection. The postoperative long-term BR was 68.6%. Empty sella, tumor maximum diameter and postoperative GH levels were independent factors predicting remission. ROC revealed that postoperative 24 h GH ≤ 1.3 ng/mL and ≤ 1.23 ng/mL were valuable predictors for 3-month and long-term remission respectively, and that postoperative 3-month GH ≤ 1.6 ng/mL and tumor maximum diameter ≤ 17 mm were predictors for delayed remission. CONCLUSION: Early postoperative GH levels can be used as predictors of remission. However, BR was not associated with preoperative somatostatin analogs therapy or Knosp grade (0-2). For patients without residual tumor or recurrence and whose GH levels are slightly elevated within 1 year after surgery, adjuvant treatments may not be necessary.

Proteogenomic landscape and clinical characterization of GH-producing pituitary adenomas/somatotroph pituitary neuroendocrine tumors.

The clinical characteristics of growth hormone (GH)-producing pituitary adenomas/somatotroph pituitary neuroendocrine tumors (GHomas/somatotroph PitNETs) vary across patients. In this study, we aimed to integrate the genetic alterations, protein expression profiles, transcriptomes, and clinical characteristics of GHomas/somatotroph PitNETs to identify molecules associated with acromegaly characteristics. Targeted capture sequencing and copy number analysis of 36 genes and nontargeted proteomics analysis were performed on fresh-frozen samples from 121 sporadic GHomas/somatotroph PitNETs. Targeted capture sequencing revealed GNAS as the only driver gene, as previously reported. Classification by consensus clustering using both RNA sequencing and proteomics revealed many similarities between the proteome and the transcriptome. Gene ontology analysis was performed for differentially expressed proteins between wild-type and mutant GNAS samples identified by nontargeted proteomics and involved in G protein-coupled receptor (GPCR) pathways. The results suggested that GNAS mutations impact endocrinological features in acromegaly through GPCR pathway induction. ATP2A2 and ARID5B correlated with the GH change rate in the octreotide loading test, and WWC3, SERINC1, and ZFAND3 correlated with the tumor volume change rate after somatostatin analog treatment. These results identified a biological connection between GNAS mutations and the clinical and biochemical characteristics of acromegaly, revealing molecules associated with acromegaly that may affect medical treatment efficacy.

Molecular genetic testing in the management of pituitary disease.

OBJECTIVE: Most pituitary tumours occur sporadically without a genetically identifiable germline abnormality, a small but increasing proportion present with a genetic defect that predisposes to pituitary tumour development, either isolated (e.g., aryl hydrocarbon receptor-interacting protein, AIP) or as part of a tumour-predisposing syndrome (e.g., multiple endocrine neoplasia (MEN) type 1, Carney complex, McCune-Albright syndrome or pituitary tumour and paraganglioma association). Genetic alterations in sporadic pituitary adenomas may include somatic mutations (e.g., GNAS, USP8). In this review, we take a practical approach: which genetic syndromes should be considered in case of different presentation, such as tumour type, family history, age of onset and additional clinical features of the patient. DESIGN: Review of the recent literature in the field of genetics of pituitary tumours. RESULTS: Genetic testing in the management of pituitary disease is recommended in a significant minority of the cases. Understanding the genetic basis of the disease helps to identify patients and at-risk family members, facilitates early diagnosis and therefore better long-term outcome and opens up new pathways leading to tumorigenesis. CONCLUSION: We provide a concise overview of the genetics of pituitary tumours and discuss the current challenges and implications of these genetic findings in clinical practice.

Growth hormone secreting pituitary adenomas show distinct extrasellar extension patterns compared to nonfunctional pituitary adenomas.

PURPOSE: Patterns of extension of pituitary adenomas (PA) may vary according to PA subtype. Understanding extrasellar extension patterns in growth hormone PAs (GHPA) vis-a-vis nonfunctional PAs (NFPAs) may provide insights into the biology of GHPA and future treatment avenues. METHODS: Preoperative MR imaging (MRI) in 179 consecutive patients treated surgically for NFPA (n = 139) and GHPA (n = 40) were analyzed to determine patterns of extrasellar growth. Extension was divided into two principal directions: cranio-caudal (measured by infrasellar/suprasellar extension), and lateral cavernous sinus invasion (CSI) determined by Knosp grading score of 3-4. Suprasellar extension was defined as tumor extension superior to the tuberculum sellae- dorsum sellae line, and inferior extension as invasion through the sellar floor into the sphenoid sinus or clivus. Categorical analysis was performed using Fisher's exact test. RESULTS: GHPAs were overall more likely to remain purely intrasellar compared to NFPA (50% vs 26%, p < 0.001). GHPAs, however, were 7 times more likely to exhibit isolated infrasellar extension compared to NFPA (20% vs 2.8%, p = 0.001). Conversely, NFPAs were twice as likely to exhibit isolated suprasellar extension compared to GHPA (60% vs 28%, p < 0.001), as well as combined suprasellar/infrasellar extension (25% vs 3%, p = 0.011). There were no overall differences in CSI between the two subgroups. DISCUSSION: GHPA and NFPA demonstrate distinct extrasellar extension patterns on MRI. GHPAs show proclivity for inferior extension with bony invasion, whereas NFPAs are more likely to exhibit suprasellar extension through the diaphragmatic aperture. These distinctions may have implications into the biology and future treatment of PAs.

Acromegaly: Medical and Surgical Considerations.

Acromegaly results from excessive secretion of insulinlike growth factor-1 and growth hormone, which most commonly occurs because of pituitary somatotrophinoma. Diagnostic features of acromegaly include elevated insulinlike growth factor-1 and growth hormone; lesion on brain MRI; and clinically dysmorphic features, such as soft tissue swelling, jaw prognathism, and acral overgrowth. Transsphenoidal resection is the primary therapy for individuals with acromegaly, even in the cases where gross total resection is not possible because of parasellar extension and cavernous sinus involvement. For recurrent or persistent disease after resection, systemic medications and stereotactic radiosurgery are used.