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Context: Colonic polyps occur in 30-40% of acromegalic patients, increasing the risk of colon carcinoma. Although debated, there is emerging evidence that metformin may play a protective role in diabetic and non-diabetic patients with colonic polyps and its use in chemoprevention is currently explored. Objective: Evaluate the prevalence of colonic polyps in acromegalic patients treated or not with metformin and explore its possible protective role. Design: Exploratory cross-sectional study in two tertiary Italian referral centres. Methods: Out of 153 acromegalic patients, we selected 58 patients (36-8 2 years; f: 33) who had at least one colonoscopy performed within the first 2 years of diagnosis. Presence of colonic polyps/cancer and related risk factors, current metformin and acetylsalicylic acid intake, disease duration, therapies for acromegaly, hormonal and metabolic parameters were assessed. Results: An overall prevalence of 36% polyps was found. Based on the presence of polyps, we identified two groups, comparable for age, BMI, disease duration, glucose, insulin, HOMA-IR, HbA1c, GH and IGF-I levels. Of the patients with polyps (including three adenocarcinomas) only 24% were treated with metformin vs 57% of patients without polyps. Multivariate analysis confirmed a significant negative association between colonic polyps and metformin intake (OR: 0.22, 95% CI: 0.06-0.77, P = 0.01), whereas no significant association was found between polyps and age (P = 0.10), overweight/obesity (P = 0.54), smoking (P = 0.15), acetylsalicylic acid intake (P = 0.99), disease duration (P = 0.96), somatostatin analogues treatment (P = 0.70). Conclusions: These findings, though deriving from an exploratory study, could suggest a protective role of metformin on the development of colonic polyps in acromegaly, and need to be confirmed in an extended study population. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to develop an open-source and reproducible digital quantitative analysis (DIA) of somatostatin receptor subtype 2a (SST2) staining in formalin-fixed paraffin-embedded tissues of pancreatic neuroendocrine tumors (panNETs) and growth hormone (GH)-secreting pituitary adenomas (GHomas). Design: SST2 immunostaining of 18 panNETs and 39 GHomas was assessed using a novel DIA protocol and compared with a widely used semi-quantitative immunoreactivity score (IRS). Methods: The DIA software calculates the staining intensity/area and the percentage of positive cells (%PC). Four representative images were selected for each sample by two independent selectors (S1 and S2), with the analysis performed by two independent analyzers (A1 and A2). Agreement between observers was calculated using the concordance correlation coefficient (CCC). Results: In panNETs, the CCC ranged 0.935-0.977 for intensity/area and 0.942-0.983 for %PC. In GHomas, the CCC ranged 0.963-0.997 for intensity/area and 0.979-0.990 for %PC. In both panNETs and GHomas, the DIA staining intensity was strongly correlated with the IRS (Spearman rho: 0.916-0.969, P< 0.001), as well as the DIA %PC with the IRS %PC (Spearman rh: 0.826-0.881, P< 0.001). In GHomas, the biochemical response to somatostatin receptor ligands correlated with SST2 expression, evaluated both as DIA intensity/area (Spearman rho: -0.448 to -0.527, P = 0.007-0.004) and DIA %PC (Spearman rho: -0.558 to -0.644, P < 0.001). Conclusions: The DIA has an excellent inter-observer agreement and showed a strong correlation with the widely used semi-quantitative IRS. The DIA protocol is an open-source, highly reproducible tool and provides a reliable quantitative evaluation of SST2 immunohistochemistry. [ABSTRACT FROM AUTHOR]

In viral pandemics, most specifically Covid-19, many patients with neuroendocrine neoplasms (NENs), including phaeochromocytomas, paragangliomas and medullary thyroid carcinoma, may develop Covid-19 in a mild or severe form, or be concerned about the influence of viral infection relative to their anti-tumoral therapy. In general, newly presenting patients should be assessed, and patients recently receiving chemotherapy, targeted therapy or radionuclide therapy, or showing tumour growth, should be closely followed. For previously diagnosed patients, who have indolent disease, some delay in routine follow-up or treatment may not be problematic. However, patients developing acute secretory syndromes due to functional neuroendocrine neoplasms (such as of the pancreas, intestine or lung), phaeochromocytomas and paragangliomas, will require prompt treatment. Patients with life-threatening Covid-19-related symptoms should be urgently treated and long-term anti-tumoral treatments may be temporarily delayed. In patients with especially aggressive NENs, a careful judgement should be made regarding the severity of any Covid-19 illness, tumour grade, and the immunosuppressant effects of any planned chemotherapy, immunotherapy (e.g. interferon-alpha), targeted therapy or related treatment. In other cases, especially patients with completely resected NENs, or who are under surveillance for a genetic disorder, a telephone or delayed consultation may be in order, balancing the risk of a delay against that of the possible development of Covid-19. [ABSTRACT FROM AUTHOR]

Neuroendocrine neoplasms (NENs) are traditionally considered as a single group of rare malignancies that originate from the highly spread neuroendocrine system. The clinical management is complex due to the high heterogeneity of these neoplasms in terms of clinical aggressiveness and response to the therapy. Indeed, a multidisciplinary approach is required to reach a personalization of the therapy, including cancer rehabilitation. In this review, we discuss the possibility to adopt a precision medicine (PM) approach in the management of NENs. To this purpose, we summarize current knowledge and future perspectives about biomarkers and preclinical in vitro and in vivo platforms, potentially useful to inform clinicians about the prognosis and for tailoring therapy in patients with NENs. This approach may represent a breakthrough in the therapy and tertiary prevention of these tumors. [ABSTRACT FROM AUTHOR]

Objective: Growth hormone (GH) deficiency is related to increased cardiova scular mortality. We studied clinical status, concentration of amino-terminal-pro B-type natriuretic-peptide (NT-proBNP) and echocardiographic parameters during long-term GH replacement (GH-R). Methods: Fifty-one patients (29 females), 45.9 ± 11.3 years (mean ± s.d.), median follow-up 36.2 months, echocardiography and laboratory determinations initially and at 12-months intervals. Results: At the last follow-up (last observation carried forward) (LFU (LOCF)) insulin-like growth-factor-1 standard deviation score (IGF-1 SDS) was ±1 in 92% of the patients. The median NT-proBNP declined signific antly and stabilized (-40.5%) at LFU (LOCF) due to patients with a basal NT-proBNP >125 ng/L (indicative of heart failure). The basal NT-proBNP and the final IGF-1 SDS were significant predictors of the NT-proBNP at LFU (LOCF). Initially left ventricular enddiastolic diameter (LVEDD), left ventricular posterior wall diameter (LVPWD) and ejection fraction (EF) were normal, while interventricular septum diameter (IVSD) and left ventricu lar mass index (LVMi) were slightly increased. LVPWD and IVSD had significantly declined by year three. The LVMi was moderately to severely abnormal in 37.3 and 52.0% of patients initially and at LFU (LOCF). At LFU (LOCF) LVMi and IG F-1 were significantly correlated in the 14 male patients of this subgroup. Conclusion: Long-term GH-R of GHD positively affected ISVD and LVPWD. In a subgroup of patients with severe GHD, LVMi increased concomitantly to the decline in NT-proBNP a nd this was positively correlated to the final IGF-1 concentration. Whether this observation indicates a positive de velopment in a structurally altered heart muscle (reversal of adverse remodelling) or poses a future risk for he art failure needs further follow-up. [ABSTRACT FROM AUTHOR]

Additionally, patients with acromegaly are followed-up sometimes for decades which offers the opportunity to perform longitudinal studies in the frame of regular check-ups for acromegaly, without dedicated site visits or extensive resources. Published by Bioscientifica Ltd. Printed in Great Britain © 2021 European Society of Endocrinology https://eje.bioscientifica.com https://doi.org/10.1530/EJE-21-0067 European Journal of Endocrinology 184:5 C9-C11 D A Niculescu Metformin and colonic polyps in acromegaly Metformin and colonic polyps in acromegaly: is the solution closer than we think?. [Extracted from the article]

OBJECTIVE: The physiologic role of circulating endogenous testosterone and estrogen concentrations in relation to lean body mass (LBM) and muscle strength is not as well documented in postmenopausal women as in elderly men. DESIGN: Three hundred and twenty-nine healthy postmenopausal women were randomly selected from a general practice population-based sample aged between 55 and 85 years. METHODS: Total testosterone and estrogen (TT and TE) and sex hormone-binding globulin (SHBG) were determined and estimates of bioavailable testosterone (free androgen index (TT/SHBG, FAI), calculated free testosterone (cFT), and estrogen (TE/SHBG, ESR) were calculated. Examinations included bone mineral density (BMD) of the spine and femoral neck (FN), LBM, maximum quadriceps extension strength (MES) and maximum handgrip strength (MGS), timed up-and-go test (TUGT), osteocalcin (OC), and urinary deoxy-pyridinoline/creatinine (DPyr). Correlations were assessed using Pearson's correlation coefficient (r). RESULTS: With advancing age, LBM, MES, MGS, BMD, and ESR significantly declined (range r: –0.356 to –0.141) and TUGT, and DPyr significantly increased (range r: 0.135 to 0.282 (P<0.05)). After age-adjustment, LBM, MES, and BMD in spine and FN were significantly related to bioavailable testosterone (range r: 0.146 to 0.193, for cFT, and 0.157 to 0.224, for FAI) and to ESR (range r: 0.162 to 0.273). OC and DPyr were significantly inversely related to ESR (r: –0.154 and –0.144 respectively). CONCLUSIONS: Age-related loss of LBM, MES and BMD in postmenopausal women is partly dependent on the presence of endogenous bioavailable testosterone and estrogen. [ABSTRACT FROM AUTHOR]

Pituitary tumors can cause symptoms of mass effect and hormonal hypersecretion that can be reversed with surgical resection or debulking of the adenoma, radiotherapy, or medical treatment. Medical treatment is the primary choice for prolactinomas because dopamine agonists are very effective in the treatment of these tumors, with rates of control (tumor size reduction and hormone suppression) as high as 80–90% for microprolactinomas and 60–75% for macroprolactinomas. The function of dopamine receptors in other histotypes of pituitary adenoma is still debated. However, new insights into receptor physiology and the introduction of new clinically available, as well as experimental, compounds have reopened a potential role of dopaminergic drugs in the medical treatment of pituitary tumors. The differences between the effectiveness and the resistance to different dopaminergic agents, the new challenging results from clinical and experimental studies, as well as the future of dopamine agonists in the therapy of pituitary tumors are discussed. [ABSTRACT FROM AUTHOR]

Dopamine and somatostatin receptor agonists inhibit hormone secretion by normal pituitary cells and pituitary adenomas. Indeed, initially several dopaminergic drugs, and lately somatostatin analogs, have been developed for the treatment of pituitary adenomas. Recently, it has been demonstrated that subtypes of somatostatin and dopamine receptors may form homo- and hetero-dimers at the membrane level, as part of their normal trafficking and function. Interestingly, a specific ligand for a given receptor may influence the activity of an apparently unrelated receptor, and the association between the two different receptors could be induced by addition of either dopamine or somatostatin. The new properties of these families of G-protein coupled receptors (GPCRs) offer a potential explanation for the apparent conflicting results observed both in vivo and in vitro in human cell systems treated with the presently available analogs. Moreover, this observation not only increases the possibilities of modulating the activities of these receptors, but also raises new questions on the role of associations of specific receptors in the control of cell functions. In fact, results from preclinical studies have shown that receptor activation may not only trigger different intracellular signaling pathways, but also induce a distinct response depending upon the specific cell type. Recently, a number of new interesting compounds (subtype selective analogs and antagonists, as well as bi-specific and hybrid somatostatin/dopamine compounds) have been developed. The effects of these new molecules have been explored in few animal and human cell lines and primary cultures from human tumors, revealing a heterogeneous, but broader, profile of activities. Further studies are certainly needed to fully elucidate the complex interplay between the GPCRs and consequent biological effects, to identify suitable therapies for controlling hormonal secretion of pituitary tumors. However, these recent observations form the basis for the application of new interesting strategies for the treatment of not only pituitary tumors but also other human malignancies. [ABSTRACT FROM AUTHOR]