Role of somatostatin receptor ligands in the treatment of acromegaly – review of literature

2011 ◽  
Vol 152 (18) ◽  
pp. 715-721 ◽  
Author(s):  
Orsolya Nemes ◽  
Emese Mezősi

Acromegaly is a rare disease with typical clinical manifestations. Untreated acromegaly carries a 2-4-fold increase in mortality in long-term outcome. The goal of treatment is double, including biochemical control of the disease (normalization of serum IGF1 levels compared to age and gender matched controls, GH levels below 1 ng/ml after oral glucose load, or random GH below 2.5 ng/ml) and control of the tumor mass. The therapeutic modalities currently available for the treatment of acromegaly are: surgery, medical therapy, radiation therapy and their combinations. The cornerstones of medical therapy in acromegaly are the somatostatin receptor ligands due to their effectiveness in controlling GH excess in 60-70 % of patients and their beneficial effects on tumor volume. Somatostatin analogues have an established role as adjuvant therapy after non-curative surgery, and evidence suggests their use as primary treatment for selected patients. The long-term use of somatostatin receptor ligands is safe and they are well tolerated. Future medical therapy consists of pasireotide, a novel, universal somatostatin receptor agonist, and a new class of drugs named dopastatins. The latter so-called chimeric molecules have strong affinity for somatostatin receptors and dopamine-2 receptors, resulting in a more effective blocking of GH secretion, according to preliminary data. The authors of this paper review the current medical therapy of acromegaly, focusing on the role of somatostatin receptor ligands. Orv. Hetil., 2011, 152, 715–721.

2021 ◽  
Vol 12 ◽  
Author(s):  
Odelia Cooper ◽  
Vivien Bonert ◽  
Ning-Ai Liu ◽  
Adam N. Mamelak

Management of aggressive pituitary adenomas is challenging due to a paucity of rigorous evidence supporting available treatment approaches. Recent guidelines emphasize the need to maximize standard therapies as well as the use of temozolomide and radiation therapy to treat disease recurrence. However, often these adenomas continue to progress over time, necessitating the use of additional targeted therapies which also impact quality of life and long-term outcomes. In this review, we present 9 cases of aggressive pituitary adenomas to illustrate the importance of a multidisciplinary, individualized approach. The timing and rationale for surgery, radiation therapy, temozolomide, somatostatin receptor ligands, and EGFR, VEGF, and mTOR inhibitors in each case are discussed within the context of evidence-based guidelines and clarify strategies for implementing an individualized approach in the management of these difficult-to-treat-adenomas.


2012 ◽  
Vol 2012 ◽  
pp. 1-22 ◽  
Author(s):  
U. Plöckinger

This paper outlines the present status of medical therapy of acromegaly. Indications for permanent postoperative treatment, postirradiation treamtent to bridge the interval until remission as well as primary medical therapy are elaborated. Therapeutic efficacy of the different available drugs—somatostatin receptor ligands (SRLs), dopamine agonists, and the GH antagonist Pegvisomant—is discussed, as are the indications for and efficacy of their respective combinations. Information on their mechanism of action, and some pharmakokinetic data are included. Special emphasis is given to the difficulties to define remission criteria of acromegaly due to technical assay problems. An algorithm for medical therapy in acromegaly is provided.


2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Elena V Varlamov ◽  
José Miguel Hinojosa-Amaya ◽  
Dawn Lim Shao Ting ◽  
Maria Fleseriu ◽  
Joao Prola

Abstract Background MRI T2 hypointensity of growth hormone (GH) secreting pituitary adenomas (PA) has been associated with better biochemical response to somatostatin receptor ligands and has been suggested to be useful in selecting patients with expected favorable response for pre- and post-surgery medical therapy. However, in most imaging centers, T2 intensity measurement is not part of standard neuroradiologist (NR) reporting. Objective To assess whether endocrinologists (Es) can reliably measure PA T2 signal intensity by calculating inter-rater reliability between Es and NR. Methods Retrospective review of MRI in 20 patients with pituitary somatotroph macroadenoma randomly selected from an IRB-approved PA database who had preoperative MRI available. T2 MRI intensity of the solid portion of the PA was compared to the temporal gray matter (GM) and white matter (WM): hypo- (PA< WM), hyper- (PA> GM), and isointense (WM <PA <GM). Measurements were performed separately by a NR and by two Es trained to take measurements by the same NR. Statistics: SPSS 25; Cohen kappa (κ). Results Patient mean age was 47 ± 20 years, with 12 females; mean largest PA diameter was 22.6 mm (range 11-45 mm). NR measured 12 hyper-, 7 iso- and 1 hypo-intense PA. Agreement was moderate between NR and E#1 (κ 0.72, 95%CI 0.751-1.0, p<0.001) and NR and E#2 (κ 0.638, 95%CI 0.351-0976, p<0.001) and strong between E#1 and E#2 (κ=0.90, 95%CI 0.309-0.903, p=0.001). Hypointense PA (by NR) was read by both Es as isointense. One hyperintense PA (by NR) was read by both Es as isointense. One isointense PA was read by E#2 as hypointense. Overall adenomas were; 9 densely granulated GH, 5 sparsely granulated GH, 3 mixed GH and prolactin, 1 plurihormonal, 1 not classified, and 1 no surgical intervention. Discussion Inter-rater reliability between the 2 Es was strong, however, it was moderate between each E and the NR. Factors that likely contributed to difference in measurement are heterogeneity of the PA, MRI quality, selection bias in choosing “most appropriate” site to measure intensity of adenoma, gray and white matter. Es could be trained to interpret the T2 intensity, although reliability with NR is only moderate. Interestingly, in this sample majority of T2 PA were hyperintense, but densely granulated, suggesting that preoperative identification of densely granulated tumors, which are also predictive of favorable SRL response, might be limited. More studies are needed to assess T2 correlation with pathology. Conclusion As T2 intensity (hyper-, hypo- or iso-) on MRI might be predictive of biochemical response to medical therapy in some patients with PA, we recommend T2 intensity to be part of neuroradiology reporting protocol. Our pilot study showed that endocrinologists could read MRIs after adequate training, but there is only moderate correlation with neuroradiologists.


Cancers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 4857
Author(s):  
Luiz Eduardo Wildemberg ◽  
Daniel Henriques ◽  
Paula C. L. Elias ◽  
Carlos Henrique de A. Lima ◽  
Nina R. de Castro Musolino ◽  
...  

Background: It is still controversial if activating mutations in the stimulatory G-protein α subunit (gsp mutation) are a biomarker of response to first generation somatostatin receptor ligands (fg-SRL) treatment in acromegaly. Thus, we aimed to evaluate whether gsp mutation predicts long-term response to fg-SRL treatment and to characterize the phenotype of patients harboring gsp mutations. Methods: GNAS1 sequencing was performed by Sanger. SST2 and SST5 were analyzed by immunohistochemistry (IHC) and real-time RT-PCR. The cytokeratin granulation pattern was evaluated by IHC. Biochemical control was defined as GH < 1.0 ng/mL and normal age-adjusted IGF-I levels. Results: gsp mutation was found in 54 out of 136 patients evaluated. Biochemical control with fg-SRL treatment was similar in gsp+ and gsp- patients (37% vs. 25%, p = 0.219). Tumors harboring gsp mutation were smaller (p = 0.035) and had a lower chance of invading cavernous sinuses (p = 0.001). SST5 protein (p = 0.047) and mRNA (p = 0.013) expression levels were higher in wild-type tumors. Conclusions: In this largest series available in the literature, we concluded that gsp is not a molecular biomarker of response to fg-SRL treatment in acromegaly. However, the importance of its negative association with cavernous sinus invasion and SST5 expression needs to be further investigated.


2020 ◽  
Vol 182 (6) ◽  
pp. D17-D29 ◽  
Author(s):  
Aart J van der Lely ◽  
Emmanuelle Kuhn ◽  
Ammar Muhammad ◽  
Eva C Coopmans ◽  
Sebastian J Neggers ◽  
...  

Current guidelines recommend the use of long-acting somatostatin receptor ligands (SRLs) first when surgery fails to correct GH/IGF-I hypersecretion in patients with acromegaly. In this issue of the journal, a pro- and contra debate will outline which arguments are in favour and which are against positioning pegvisomant (PEGV), a GH receptor antagonist, as the first-line treatment modality of acromegaly. The task of the pros was to promote a paradigm shift towards repositioning PEGV as first-line treatment as PEGV is safe and more effective than the first- and second-generation of SRLs. SRLs, when prescribed together with PEGV can still reduce tumour size when necessary, while they decrease the necessary dose of PEGV by around 50% in the average patient. They conclude that PEGV must move up towards the first-line treatment. For the cons, SRLs remain the first-line medical treatment. Indeed, even if, in recent studies, the remission rate is lower than initially claimed, SRLs are still effective not only for normalizing GH/IGF-I levels in half of the patients but also for inducing tumour shrinkage, improving comorbidities and headaches and reversing excess mortality. They are more convenient for use with their monthly administration and have a remarkable safety profile as demonstrated by the very prolonged experience acquired by more than 30 years of use. Finally, the cost-effectiveness of first-generation SRLs is better than that of PEGV. For all these reasons, cons consider that SRLs remain the best first medical treatment in patients requiring medical therapy.


2019 ◽  
Vol 181 (2) ◽  
pp. R57-R71 ◽  
Author(s):  
Jens Bollerslev ◽  
Ansgar Heck ◽  
Nicoleta Cristina Olarescu

Acromegaly is a rare and challenging disease calling for management in highly specialised multidisciplinary teams (MDTs). Untreated disease has severe morbidity and a clearly increased mortality. Major attainments have been gained over the latest decades, and therefore, the aim of this review is to discuss recent achievements in modern multimodal therapy of acromegaly performed by MDTs, with an emphasis on an individualised, proactive management from the time of diagnosis to long-term outcome. Treatment by surgery is the only potential curative treatment, however, even with modern techniques still with modest cure rates, leaving the patients to often long-term medical treatment. Treatment strategies have changed dramatically in the Western world over recent years, implying a more proactive treatment algorithm often with a shorter or longer pre-surgical treatment period with somatostatin receptor ligands (SRLs). Not all patients will however respond to primary treatment with conventional SRLs and there has recently been a development of potential biomarkers for response that has been implemented in the clinical routine. By today, multimodal treatment can bring every patient in remission, but still almost a third of all patients are undertreated according to large, international registries. On the other hand, it might be a challenge not to over treat thereby bringing the patient into a state of relative or absolute growth hormone deficiency. Clinical series published during the last decade on treatment of patients with acromegaly have indicated a normalisation of mortality, most probably reflecting the proactive and individualised modern treatment. In conclusion, modern, multimodal treatment seems to have normalised mortality, but still the patients suffer from a high multi-organ morbidity and often multi-pharmacy. Every patient should receive an individualised, proactive treatment in order to improve long-term outcome and to reduce costs for the society.


Author(s):  
W K M G Amarawardena ◽  
K D Liyanarachchi ◽  
J D C Newell-Price ◽  
R J M Ross ◽  
D Iacovazzo ◽  
...  

Summary The granulation pattern of somatotroph adenomas is well known to be associated with differing clinical and biochemical characteristics, and it has been shown that sparsely granulated tumours respond poorly to commonly used somatostatin receptor ligands (SRLs). We report a challenging case of acromegaly with a sparsely granulated tumour resistant to multiple modalities of treatment, ultimately achieving biochemical control with pasireotide. A 26-year-old lady presented with classical features of acromegaly, which was confirmed by an oral glucose tolerance test. Insulin-like growth factor 1 (IGF1) was 1710 µg/L (103–310 µg/L) and mean growth hormone (GH) was >600 U/L. MRI scan showed a 4 cm pituitary macroadenoma with suprasellar extension and right-sided cavernous sinus invasion. She underwent trans-sphenoidal pituitary surgery. Histology displayed moderate amounts of sparsely granular eosinophilic cytoplasm, staining only for GH. Postoperative investigations showed uncontrolled disease (IGF1:1474 µg/L, mean GH:228 U/L) and residual tumour in the cavernous sinus. She received external beam fractionated radiation. Over the years, she received octreotide LAR (up to 30 mg), lanreotide (up to 120 mg) two weekly, cabergoline, pegvisomant and stereotactic radiosurgery to no avail. Only pegvisomant resulted in an element of disease control; however, this had to be stopped due to abnormal liver function tests. Fifteen years after the diagnosis, she was started on pasireotide 40 mg monthly. Within a month, her IGF1 dropped and has remained within the normal range (103–310 µg/L). Pasireotide has been well tolerated, and there has been significant clinical improvement. Somatostatin receptor subtyping revealed a positivity score of two for both sst5 and sst2a subtypes. Learning points: Age, size of the tumour, GH levels on presentation, histopathological type and the somatostatin receptor status of the tumour in acromegaly should be reviewed in patients who poorly respond to first-generation somatostatin receptor ligands. Tumours that respond poorly to first-generation somatostatin receptor ligands, especially sparsely granulated somatotroph adenomas, can respond to pasireotide and treatment should be considered early in the management of resistant tumours. Patients with membranous expression of sst5 are likely to be more responsive to pasireotide.


2014 ◽  
Vol 52 (3) ◽  
pp. R223-R240 ◽  
Author(s):  
Daniel Cuevas-Ramos ◽  
Maria Fleseriu

Somatostatin (SST), an inhibitory polypeptide with two biologically active forms SST14 and SST28, inhibits GH, prolactin (PRL), TSH, and ACTH secretion in the anterior pituitary gland. SST also has an antiproliferative effect inducing cell cycle arrest and apoptosis. Such actions are mediated through five G-protein-coupled somatostatin receptors (SSTR): SSTR1–SSTR5. In GH-secreting adenomas, SSTR2 expression predominates, and somatostatin receptor ligands (SRLs; octreotide and lanreotide) directed to SSTR2 are presently the mainstays of medical therapy. However, about half of patients show incomplete biochemical remission, but the definition of resistanceper seremains controversial. We summarize here the determinants of SRL resistance in acromegaly patients, including clinical, imaging features as well as molecular (mutations, SSTR variants, and polymorphisms), and histopathological (granulation pattern, and proteins and receptor expression) predictors. The role of SSTR5 may explain the partial responsiveness to SRLs in patients with adequate SSTR2 density in the cell membrane. In patients with ACTH-secreting pituitary adenomas, i.e. Cushing's disease (CD), SSTR5 is the most abundant receptor expressed and tumors show low SSTR2 density due to hypercortisolism-induced SSTR2 down-regulation. Clinical studies with pasireotide, a multireceptor-targeted SRL with increased SSTR5 activity, lead to approval of pasireotide for treatment of patients with CD. Other SRL delivery modes (oral octreotide), multireceptor-targeted SRL (somatoprim) or chimeric compounds targeting dopamine D2 receptors and SSTR2 (dopastatin), are briefly discussed.


Cancers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 2093
Author(s):  
Adrien Holzgreve ◽  
Nathalie L. Albert ◽  
Norbert Galldiks ◽  
Bogdana Suchorska

This review provides an overview of current applications and perspectives of PET imaging in neuro-oncological surgery. The past and future of PET imaging in the management of patients with glioma and brain metastases are elucidated with an emphasis on amino acid tracers, such as O-(2-[18F]fluoroethyl)-L-tyrosine (18F-FET). The thematic scope includes surgical resection planning, prognostication, non-invasive prediction of molecular tumor characteristics, depiction of intratumoral heterogeneity, response assessment, differentiation between tumor progression and treatment-related changes, and emerging new tracers. Furthermore, the role of PET using specific somatostatin receptor ligands for the management of patients with meningioma is discussed. Further advances in neuro-oncological imaging can be expected from promising new techniques, such as hybrid PET/MR scanners and the implementation of artificial intelligence methods, such as radiomics.


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