Search

Acromegaly is a rare disease. Improvements in lifespan in these patients have recently been reported due to transsphenoidal surgery (TSS), advances in medical therapy, and strict criteria for defining disease remission. This document reports the opinions of a group of Italian experts who have gathered together their prolonged clinical experience in the diagnostic and therapeutic challenges of acromegaly patients. Both GH and IGF-I (only IGF-I in those treated with Pegvisomant) are needed in the diagnosis and follow-up. Comorbidities (cardio-cerebrovascular disease, sleep apnea, metabolic derangement, neoplasms, and bone/joint disease) should be specifically addressed. Any newly diagnosed patient should be referred to a multidisciplinary team experienced in the treatment of pituitary adenomas.

Prolactinomas are the most frequent pituitary adenomas. Prolactinoma may occur in different clinical settings and always require an individually tailored approach. This is the reason why a panel of Italian neuroendocrine experts was charged with the task to provide indications for the diagnostic and therapeutic approaches that can be easily applied in different contexts. The document provides 15 recommendations for diagnosis and 54 recommendations for treatment, issued according to the GRADE system. The level of agreement among panel members was formally evaluated by RAND-UCLA methodology. In the last century, prolactinomas represented the paradigm of pituitary tumors for which the development of highly effective drugs obtained the best results, allowing to avoid neurosurgery in most cases. The impressive improvement of neurosurgical endoscopic techniques allows a far better definition of the tumoral tissue during surgery and the remission of endocrine symptoms in many patients with pituitary tumors. Consequently, this refinement of neurosurgery is changing the therapeutic strategy in prolactinomas, allowing the definitive cure of some patients with permanent discontinuation of medical therapy.

Background: Somatic mutations in the ubiquitin-specific protease 8 (USP8) gene have recently been shown to occur in ACTH-secreting pituitary adenomas, thus calling attention to the ubiquitin system in corticotrope adenomas. Objectives: Assess the consequences of USP8 mutations and establish the role of ubiquitin on ACTH turnover in human ACTH-secreting pituitary adenomas. Methods: USP8 mutation status was established in 126 ACTH-secreting adenomas. Differences in ACTH secretion and POMC expression from adenoma primary cultures and in microarray gene expression profiles from archival specimens were sought according to USP8 sequence. Ubiquitin/ACTH coimmunoprecipitation and incubation with MG132, a proteasome inhibitor, were performed in order to establish whether ubiquitin plays a role in POMC/ACTH degradation in corticotrope adenomas. Results: USP8 mutations were identified in 29 adenomas (23%). Adenomas presenting USP8 mutations secreted greater amounts of ACTH and expressed POMC at higher levels compared to USP wild-type specimens. USP8 mutant adenomas were also more sensitive to modulation by CRH and dexamethasone in vitro. At microarray analysis, genes associated with endosomal protein degradation and membrane components were downregulated in USP8 mutant adenomas as were AVPR1B, IL11RA, and PITX2. Inhibition of the ubiquitin-proteasome pathway increased ACTH secretion and POMC itself proved a target of ubiquitylation, independently of USP8 sequence status. Conclusions: Our study has shown that USP8 mutant ACTH-secreting adenomas present a more “typical” corticotrope phenotype and reduced expression of several genes associated with protein degradation. Further, ubiquitylation is directly involved in intracellular ACTH turnover, suggesting that the ubiquitin-proteasome system may represent a target for treatment of human ACTH-secreting adenomas.

Simple Summary Giant pituitary adenomas are highly invasive tumors whose treatment is challenging. Surgery is their management mainstay. However, there is no consensus about the type of approach. Open transcranial, microscopic, and endoscopic trans-sphenoidal approaches have all been employed, alone or in combination. Extended endoscopic endonasal techniques may represent a versatile and safe one-stage approach. Our research aimed at evaluating prospectively their applicability, effectiveness, and safety in a multicenter series, to acquire further evidence toward its use in the treatment of those challenging lesions. Ninety-six patients were recruited and followed-up for 52.4 months on average. Most of them (81.2%) presented with visual deficits and >50% had various degrees of adenohypophysis insufficiency. Resection of at least 75% of initial volume was achieved in all cases, with 98.7% visual improvement, >50% endocrine deficit recovery and a permanent complication rate of 4.2%, indicating extended endoscopic endonasal approaches as a valuable treatment option. Abstract Purpose: To evaluate factors influencing clinical and radiological outcome of extended endoscopic endonasal transtuberculum/transplanum approach (EEA-TTP) for giant pituitary adenomas (GPAs). Methods: We recruited prospectively all consecutive GPAs patients undergoing EEA-TTP between 2015 and 2019 in 5 neurosurgical centers. Preoperative clinical and radiologic features, visual and hormonal outcomes, extent of resection (EoR), complications and recurrence rates were recorded and analyzed. Results: Of 1169 patients treated for pituitary adenoma, 96 (8.2%) had GPAs. Seventy-eight (81.2%) patients had visual impairment, 12 (12.5%) had headaches, 3 (3.1%) had drowsiness due to hydrocephalus, and 53 (55.2%) had anterior pituitary insufficiency. EoR was gross or near-total in 46 (47.9%) and subtotal in 50 (52.1%) patients. Incomplete resection was associated with lateral suprasellar, intraventricular and/or cavernous sinus extension and with firm/fibrous consistence. At the last follow-up, all but one patient (77, 98.7%) with visual deficits improved. Headache improved in 8 (88.9%) and anterior pituitary function recovered in 27 (50.9%) patients. Recurrence rate was 16.7%, with 32 months mean recurrence-free survival. Conclusions: EEA-TTP is a valid option for GPAs and seems to provide better outcomes, lower rate of complications and higher EoR compared to one- or multi-stage microscopic, non-extended endoscopic transsphenoidal, and transcranial resections.

Pituitary carcinomas (PCa) are extremely rare, indistinguishable from pituitary adenomas on histopathological grounds and have a poor prognosis. Most PCa start as PRL or ACTH secreting tumors in males, with relapsing invasive behaviour, refractoriness to medical and radiotherapy and increasing hormonal levels. The presence of distant metastases is still required for the diagnosis of PCa. The association with genetic endocrine diseases must be taken into account, since it adds further risk of evolution towards malignancy. Intradural spinal metastases have also been reported, so a complete craniospinal MR evaluation is recommended, when clinically indicated. We report a case of PCa, associated with MEN1 syndrome, with evidence of meningeal spread to the tentorium cerebelli, clival dura and spinal drop metastases mimicking spinal nerves schwannomas.

Silibinin, a milk thistle extract with known hepatoprotective effects, has recently been shown to act upon tumoral corticotropes and revert the Cushingoid phenotype in an allograft mouse model (Riebold et al 2015). Silbinin is known to inhibit HSP90 -a chaperone to the glucocorticoid receptor- thereby restoring sensitivity to glucocorticoid negative feedback in tumoral corticotropes. Aim of the present study was to assess the effect of silibinin on ACTH synthesis and secretion by human corticotrope adenomas in vitro. Methods: Eight human ACTH-secreting pituitary adenomas were collected during surgery and established in culture as per our protocol (Pecori Giraldi et al 2011). Specimens were treated with 10 - 50 µM silibinin for up to 72 hours. ACTH medium levels were measured by Elisa; POMC expression was assessed by RT-PCR (Cassarino et al 2017). Results. Silibinin reduced spontaneous ACTH secretion to a variable extent in individual adenomas: from 32 to 79% of baseline at 4h, and 54 - 85 % of baseline at 48 and 72h. Silibinin was also effective in reinstating or enhancing sensitivity to steroid negative feedback: ACTH decreases during 10–50 µM silibinin incubation ranged from 10 to 63% of dexamethasone-treated wells at 4 hours, 70 -80% at 48 hours and 36 to 80% at 72 hours, indicating long-lasting effect on glucocorticoid sensitivity. Silibinin induced a variable decrease in POMC expression, both as regards expression in control and dexamethasone-treated wells; some specimens exhibited a marked sensitivity to the inhibitory effect, with POMC expression decreasing to less than 50% of control. Conclusions:, this data suggests that silibinin can inhibit ACTH secretion and POMC synthesis and restore sensitivity to negative glucocorticoid feedback. References: Cassarino et al (2017) Endocrine55: 853–860. Pecori Giraldi et al (2011) Journal of Neuroendocrinology23:1214–21. Riebold et al (2015) Nature Medicine21:276–280.

Any newly diagnosed patient should be referred to a multidisciplinary team experienced in the treatment of pituitary adenomas. The therapeutic management of acromegaly always requires a personalized strategy. Normal age-matched IGF-I values are the treatment goal. Transsphenoidal surgery by an expert neurosurgeon is the primary treatment modality for most patients, especially if there are neurological complications. In patients with poor clinical conditions or who refuse surgery, primary medical treatment should be offered, firstly with somatostatin analogs (SSAs). In patients who do not reach hormonal targets with first-generation depot SSAs, a second pharmacological option with pasireotide LAR or pegvisomant (alone or combined with SSA) should be offered. Irradiation could be proposed to patients with surgical remnants who would like to be free from long-term medical therapies or those with persistent disease activity or tumor growth despite surgery or medical therapy. Since the therapeutic tools available enable therapeutic targets to be achieved in most cases, the challenge is to focus more on the quality of life.

BACKGROUND: Somatic mutations in the ubiquitin-specific protease 8 (USP8) gene have recently been shown to occur in ACTH-secreting pituitary adenomas, thus calling attention to the ubiquitin system in corticotrope adenomas. OBJECTIVES: Assess the consequences of USP8 mutations and establish the role of ubiquitin on ACTH turnover in human ACTH-secreting pituitary adenomas. METHODS: USP8 mutation status was established in 126 ACTH-secreting adenomas. Differences in ACTH secretion and POMC expression from adenoma primary cultures and in microarray gene expression profiles from archival specimens were sought according to USP8 sequence. Ubiquitin/ACTH coimmunoprecipitation and incubation with MG132, a proteasome inhibitor, were performed in order to establish whether ubiquitin plays a role in POMC/ACTH degradation in corticotrope adenomas. RESULTS: USP8 mutations were identified in 29 adenomas (23%). Adenomas presenting USP8 mutations secreted greater amounts of ACTH and expressed POMC at higher levels compared to USP wild-type specimens. USP8 mutant adenomas were also more sensitive to modulation by CRH and dexamethasone in vitro. At microarray analysis, genes associated with endosomal protein degradation and membrane components were downregulated in USP8 mutant adenomas as were AVPR1B, IL11RA, and PITX2. Inhibition of the ubiquitin-proteasome pathway increased ACTH secretion and POMC itself proved a target of ubiquitylation, independently of USP8 sequence status. CONCLUSIONS: Our study has shown that USP8 mutant ACTH-secreting adenomas present a more “typical” corticotrope phenotype and reduced expression of several genes associated with protein degradation. Further, ubiquitylation is directly involved in intracellular ACTH turnover, suggesting that the ubiquitin-proteasome system may represent a target for treatment of human ACTH-secreting adenomas.

(1) Background. Cushing&rsquo, s disease presents gender disparities in prevalence and clinical course. Little is known, however, about sexual dimorphism at the level of the corticotrope adenoma itself. The aim of the present study was to evaluate molecular features of ACTH-secreting pituitary adenomas collected from female and male patients with Cushing&rsquo, s disease. (2) Methods. We analyzed 153 ACTH-secreting adenomas collected from 31 men and 122 women. Adenomas were established in culture and ACTH synthesis and secretion assessed in basal conditions as well as during incubation with CRH or dexamethasone. Concurrently, microarray analysis was performed on formalin-fixed specimens and differences in the expression profiles between specimens from male and female patients identified. (3) Results. ACTH medium concentrations in adenomas obtained from male patients were significantly lower than those observed in adenomas from female patients. This could be observed for baseline as well as modulated secretion. Analysis of corticotrope transcriptomes revealed considerable similarities with few, selected differences in functional annotations. Differentially expressed genes comprised genes with known sexual dimorphism, genes involved in tumour development and genes relevant to pituitary pathophysiology. (4) Conclusions. Our study shows for the first time that human corticotrope adenomas present sexual dimorphism and underlines the need for a gender-dependent analysis of these tumours. Differentially expressed genes may represent the basis for gender-tailored target therapy.

ACTH-secreting pituitary tumors are by definition partially autonomous, i.e., secrete ACTH independent of physiological control. However, only few, small-sized studies on proopiomelanocortin (POMC) and its regulation by corticotropin-releasing hormone (CRH) or glucocorticoids are available. Objective of the present study was to report on constitutive and CRH- and dexamethasone-regulated POMC, CRH (CRH-R1), and glucocorticoid receptor (NR3C1) gene expression in a large series of human corticotrope adenomas. Fifty-three ACTH-secreting adenomas were incubated with 10 nM CRH or 10 nM dexamethasone for 24 h. POMC, CRH-R1, NR3C1, and its alpha and beta isoforms were quantified and medium ACTH measured. Constitutive POMC expression proved extremely variable, with macroadenomas exhibiting higher levels than microadenomas. POMC increased during CRH in most specimens; conversely, changes induced by dexamethasone were varied, ranging from decrease to paradoxical increase. No correlation between POMC and ACTH was detected in any experimental condition. CRH-R1 expression was not linked to the response to CRH while NR3C1 was expressed at greater levels in specimens who failed to inhibit during dexamethasone; glucocorticoid receptor α was the more abundant isoform and subject to down-regulation by dexamethasone. Our results demonstrate a considerable variability in POMC expression among tumors and no correlation between POMC and ACTH, suggesting that POMC peptide processing/transport plays a major role in modulating ACTH secretion. Further, CRH-R1 and NR3C1 expression were not linked to the expected ligand-induced outcome, indicating that receptor signaling rather than abundance determines corticotrope responses. Our findings pave the way to new avenues of research into Cushing’s disease pathophysiology. Electronic supplementary material The online version of this article (doi:10.1007/s12020-016-0990-x) contains supplementary material, which is available to authorized users.

Altered excitatory synaptic activity is likely a key factor in the neuronal hyperexcitability of developmental cerebral malformations. Using a combined morphologic and molecular approach, we investigated the NMDA receptor and related protein composition in human epileptic patients affected by periventricular nodular heterotopia, subcortical band heterotopia, or focal cortical dysplasia. Our results indicate that expression levels of specific NMDA receptor subunits are altered in both cerebral heterotopia and cortical dysplasia. A selective increase in the NR2B subunit was present in all cortical dysplasia, whereas the expression level of NR2A and NR2B subunits was significantly downregulated in all patients with heterotopia. NR2B upregulation in cortical dysplasia was greater in the total homogenate than the postsynaptic membrane fraction, suggesting that mechanisms other than increased ionic influx through the postsynaptic membrane may sustain hyperexcitability in dysplastic neurons. In cerebral heterotopia, the NR2A and NR2B downregulation was accompanied by less evident reduction of the SAP97 and PSD-95 proteins of the MAGUK family, thus suggesting that NMDA impairment was associated with altered molecular structure of the postsynaptic membrane. Our results demonstrate that diverse human developmental malformations are associated with different alterations of the NMDA receptor, which may contribute to the genesis of epileptic phenomena.

Prepro-thyrotrophin-releasing hormone (TRH) (178-199), a 22-amino acid cleavage product of the TRH prohormone, has been postulated to act as an adrenocorticotrophin hormone (ACTH)-release inhibitor. Indeed, although in vitro evidence indicates that this peptide may inhibit basal and stimulated ACTH secretion in rodent anterior pituitary primary cultures and cell lines, not all studies concur and no study has as yet evaluated the effect of this peptide in Cushing's disease. The present study aimed to test the effect of preproTRH(178-199) in human tumoural corticotrophs. Twenty-four human ACTH-secreting pituitary tumours (13 macroadenomas, 11 microadenomas) were collected during surgery and incubated with 10 or 100 n. m preproTRH(178-199). ACTH secretion was assessed after 4 and 24 h of incubation by immunometric assay and expressed relative to levels observed in control, unchallenged wells (= 100%). Parallel experiments were performed in rat anterior pituitary primary cultures. A clear inhibition of ACTH secretion at 4 and 24 h was observed in 12 specimens (for 10 n. m ppTRH: 70 ± 4% control at 4 h and 83 ± 5% control at 24 h; for 100 n. m ppTRH: 70 ± 4% control at 4 h and 85 ± 5% control at 24 h), whereas a mild and short-lasting stimulatory effect was observed in three tumours and no changes in ACTH secretion in the remaining nine tumoural specimens. The inhibitory effect of preproTRH(178-199) was more evident in macroadenomas and significantly correlated with sensitivity to dexamethasone inhibition. Significant inhibition of ACTH secretion by preproTRH(178-199) in rat pituitary cultures was observed after 24 h of incubation. The present study conducted in a large series of human corticotroph tumours shows that preproTRH(178-199) inhibits tumoural ACTH secretion in a sizable proportion of specimens, in close relation to the size of the tumour and its sensitivity to glucocorticoid negative feedback. This appears a promising avenue of research and further studies are warranted to explore the full scope of preproTRH(178-199) as a regulator of ACTH secretion. © 2010 The Authors. Journal Compilation © 2010 Blackwell Publishing Ltd.

Kilovoltage x-ray projection images (kV images for brevity) are increasingly available in image guided radiotherapy (IGRT) for patient positioning. These images are two-dimensional (2D) projections of a three-dimensional (3D) object along the x-ray beam direction. Projecting a 3D object onto a plane may lead to ambiguities in the identification of anatomical structures and to poor contrast in kV images. Therefore, the use of kV images in IGRT is mainly limited to bony landmark alignments. This work proposes a novel subtraction technique that isolates a slice of interest (SOI) from a kV image with the assistance of a priori information from a previous CT scan. The method separates structural information within a preselected SOI by suppressing contributions to the unprocessed projection from out-of-SOI-plane structures. Up to a five-fold increase in the contrast-to-noise ratios (CNRs) was observed in selected regions of the isolated SOI, when compared to the original unprocessed kV image. The tomographic image via background subtraction (TIBS) technique aims to provide a quick snapshot of the slice of interest with greatly enhanced image contrast over conventional kV x-ray projections for fast and accurate image guidance of radiation therapy. With further refinements, TIBS could, in principle, provide real-time tumor localization using gantry-mounted x-ray imaging systems without the need for implanted markers.

Neurosurgery is regarded as the first-line treatment of acromegaly. Because of its low cure rate in macro and invasive adenoma, the role of primary medical treatment is debated.Our objective was to evaluate primary pharmacological treatment in acromegaly.We conducted an open prospective study at two Italian tertiary level centers.We studied 67 consecutive patients (36 women; age, 54.9 +/- 14.2 yr; 72% bearing macroadenoma).Individually tailored octreotide LAR (OCLAR) was administered.Outcomes included safe GH (2.5 mug/liter), normal age-matched IGF-I levels, and tumor shrinkage.After a median follow-up of 48 months (range, 6-108 months), safe GH levels and normal age-matched IGF-I values were obtained by 68.7 and 70.1% of patients, respectively. Hormonal endpoints were achieved regardless of basal levels, and early results were predictive of outcome. Tumor shrank in 82.1% of patients by 62 +/- 31% (range, 0-100%), decreasing from 2101 +/- 2912 to 1010 +/- 2196 mm(3) (P0.0001). The higher the basal GH values and the greater the GH/IGF-I changes on treatment, the greater the tumor shrinkage. Tumor disappeared in three patients and was progressively reduced to empty sella in five patients; apparent magnetic resonance imaging cavernous sinus invasion disappeared in three. In males, testosterone increased, restoring eugonadism in 64% of hypogonadal patients.The efficacy on GH/IGF-I levels in unselected patients and the outstanding volumetric control indicate that treatment with OCLAR may be the first therapeutic approach to all acromegalic patients not amenable to surgical cure. Tumor shrinkage might also encourage the evaluation of primary OCLAR adoption in patients with initial visual field defects.

Context: Surgery is a cornerstone in the treatment of acromegaly, but its efficacy in large, invasive tumors is scant. Objective: The objective of this study was to investigate whether partial surgical removal of GH-secreting pituitary tumors enhances the response rate to somatostatin analogs (SSA; sc octreotide, slow-release octreotide, and lanreotide). Design: This was a multicenter, open, retrospective study. Setting: The study was performed at university hospitals. Subjects and Methods: Eighty-six patients (42 women and 44 men; age, 42 ± 14 yr) with acromegaly were studied. Interventions: Patients underwent two courses of octreotide, lanreotide, or slow-release octreotide treatments before and after surgery of at least 6 months. Main Outcome Measure: The main outcome measure was normal IGF-I levels for age. Results: Presurgical SSA treatment significantly decreased GH and IGF-I levels in all patients. GH levels were less than 2.5 μg/liter in 12 patients (14%); IGF-I levels normalized in nine (10%). After surgery, GH and IGF-I levels further decreased in all patients; tumor removal was greater than 75% in 50 (58%), 50.1–75% in 21 (24%), 25.1–50% in 10 (12%), and less than 25% in five patients (6%). Preoperatively, pituitary function was impaired in 12 patients (14%). Postsurgical SSA treatment lowered GH levels to less than 2.5 μg/liter in 49 (56%) and normalized IGF-I levels in 48 patients (55%). The success rate was significantly increased compared with that before surgery (P < 0.0001). GH (r = −0.48; P < 0.0001) and IGF-I levels (r = −0.38; P = 0.0003) after postsurgery SSA treatment correlated with the amount of tumor surgically removed. After surgery, pituitary function was impaired in 28 patients (32.6%) and was improved in 12 patients (13.9%). The cumulative prevalence of pituitary deficiency did not change during the study (normal function from 40 to 42%; deficiency from 60 to 58%). Conclusions: Surgical tumor removal (>75%) enhances the response to SSAs without impairing pituitary function. Our data indicate that surgical debulking has a significant place in the treatment algorithm of acromegaly.

The effects of a very prolonged treatment with octreotide (OC)-long-acting repeatable (LAR) were retrospectively evaluated in 110 patients with acromegaly, showing a GH/IGF-I decrease of at least 20% vs. baseline after a short-term (6-month) OC-LAR challenge. OC-LAR was given (20 mg, im, every 28 d for 3 injections, then individually tailored) as adjuvant treatment (AT) in 59. The other 51 [primary treatment (PT)] were naive or previously treated by pharmacotherapy. IGF-I normalized in 83 patients [75%; from 770 +/- 26 (mean +/- SE) to 276 +/- 15 micro g/liter; P < 0.0001; median follow-up, 30 months; range, 18-54 months). A progressive increase in the rate of IGF-I normalization was observed. GH fell to less than 2.5 micro g/liter in 72% and to less than 1 micro g/liter in 27% (from 20.7 +/- 2.4 to 2.2 +/- 0.2 micro g/liter; P < 0.0001). PT and AT patients achieved similar final GH/IGF-I levels and rates of normalization. Patients attaining safe GH and normal IGF-I had GH levels below 5 micro g/liter after 3 months and IGF-I levels below 550 micro g/liter after 6 months. No tachyphylaxis was observed. The up-titration to 30 mg improved IGF-I suppression. Elderly patients had greater sensitivity. Tumor shrank in 46% of assessable patients, in 77% of PT patients, and in 91% of naive patients. The powerful suppression of GH/IGF-I levels without tachyphylaxis, the finding of progressive increase in the rate of IGF-I normalization and of superimposable effects in PT and AT patients, and the predictive value of short-term results support the role of PT of acromegaly with OC-LAR in at least some patients.

OBJECTIVE To assess the role that neuronavigation plays in assisting endoscopic transsphenoidal reoperations for recurrent pituitary adenomas. METHODS During a 45-month period, 19 endoscopic endonasal transsphenoidal reoperations were performed for recurrent pituitary adenomas. In 11 of 19 patients, the procedure was performed with the aid of an optically guided system. Clinical records were reviewed retrospectively, with attention to the following: comparison of baseline clinical data, the duration of surgery, and the postoperative course and complications of both image-guided and non-image-guided endoscopic reoperations. In addition, to test the reliability of the neuronavigation system, we made measurements of intraoperative accuracy in five additional transnasal endoscopic procedures in “virgin” noses and sphenoidal sinuses. RESULTS In both groups studied, we found no difference with regard to either morbidity or mortality, which were null. The mean setup time was 13 minutes shorter in non-image-guided procedures (P = 0.021), and the operative time was 36 minutes shorter in image-guided procedures (P = 0.038). No other statistically significant differences were found between the two groups. In all cases, we found that the system performed without malfunction. Continuous information regarding instrument location and trajectory was provided to the surgeon. Measurements of the intraoperative accuracy in the axial, coronal, and sagittal planes indicated a mean intraoperatively verified system error of 1.6 ± 0.6 mm. CONCLUSION Neuronavigation can be applied during endonasal transsphenoidal endoscopic surgery and requires a minimal amount of time. It makes reoperation easier, faster, and probably safer.