The corellation between somatostatin receptors expression and octreotide treatment in non-functioning pituitary adenomas

2016 ◽  
Vol 62 (5) ◽  
pp. 69
Author(s):  
Natalia Bozena Zawada
Keyword(s):  
Pituitary Adenomas ◽  
Tumour Size ◽  
Somatostatin Receptors ◽  
Somatostatin Analogues ◽  
Strong Expression ◽  
Tumour Shrinkage ◽  
Octreotide Treatment ◽  
Control Magnetic Resonance Imaging ◽  
Positive Results ◽  
Non Functioning Pituitary Adenomas

Introduction. Neurosurgery, which is the treatment of choice of non-functioning pituitary adenomas (NFPA), is often incurative. It usually leaves tumour residue that can regrow in the future. There is no established management for the postoperative period of NFPA, however, some data suggest that somatostatin analogues (SSA) can be effective, especially regarding somatostatin receptors (SSTR) presence in NFPA. SSTR scintigraphy and immunohistochemistry are used to assess SSTR expression in NFPA.Aim: to analyse the outcome of SSA treatment in NFPA and to correlate it with the results of SSTR scintigraphy and immunohistochemistry.Material and methods. Twenty six NFPA patients after incomplete neurosurgery with positive results of scintigraphy and immunohistochemistry were included in the study. All patients were treated with octreotide LAR 20mg intramuscular every 4 weeks. The tumour size was evaluated in control magnetic resonance imaging after 2 years of SSA therapy.Results. Tumour size remained stable in the majority of NFPA. Adenoma size reduction was observed in 2 patients with strong expression of SSTR2 in both scintigraphy and immunohistochemistry. Increase of tumour size was noticed in 4 patients whose tumours were characterised not only by the presence of SSTR2 and SSTR5 but also by strong expression of SSTR1 in immunohistochemistry.Conclusions. Only strong expression of SSTR2 can predict patients response to SSA treatment in NFPA. However, strong expression of SSTR1 observed in some of NFPA gives hope that introduction of new broad spectrum SSA like pasireotide would be more effective, especially in tumour shrinkage.

scholarly journals Antitumour Effects of Somatostatin Analogues in the Treatment of Neuroendocrine Tumours

2012 ◽  
Vol 08 (03) ◽  
pp. 156
Author(s):  
Diogo Assed Bastos ◽  
Brenda Gumz ◽  
Frederico Costa ◽  
◽  
◽  
...  
Keyword(s):  
Neuroendocrine Tumours ◽  
Antitumour Activity ◽  
Somatostatin Receptors ◽  
Somatostatin Analogues ◽  
Antiangiogenic Activity ◽  
Tumour Shrinkage ◽  
Phosphotyrosine Phosphatases ◽  
Antitumour Effects

Neuroendocrine tumours (NETs) are rare and heterogeneous neoplasms that can present with functional syndromes due to the hypersecretion of peptides. Somatostatin analogues (SSAs) have been used since the 1980s for the treatment of neuroendocrine tumours, with the aim of controlling the symptoms of functioning tumours and improving patients’ quality of life. Data from preclinical studies offer evidence of both direct and indirect mechanisms by which SSAs can exert antitumour effects. The activation of somatostatin receptors by SSAs leads to the activation of phosphotyrosine phosphatases, which control downstream apoptotic and antiproliferation signalling pathways. Also, the suppression of secretion of several growth factors and inhibition of antiangiogenic activity by SSAs indirectly inhibits tumour cell proliferationin vitro. Previous uncontrolled studies had shown tumour shrinkage and disappearance in response to the SSA octreotide. Recent results from the randomised and placebo-controlled PROMID trial have demonstrated that octreotide has antitumour activity in patients with metastatic mid-gut NETs. This article examines recent data providing evidence of the antitumour activity of somatostatin analogues.

scholarly journals MON-467 Expression of Somatostatin Receptors in Aggressive Non-Functioning Pituitary Adenomas

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Alfonso Soto ◽  
Eva Venegas-Moreno ◽  
Noelia Gros Herguido ◽  
Elena Dios ◽  
Alvaro Flores-Martínez ◽  
...  
Keyword(s):  
Pituitary Adenomas ◽  
Somatostatin Receptors ◽  
Non Functioning Pituitary Adenomas

Antitumour Effects of Somatostatin Analogues in the Treatment of Neuroendocrine Tumours

2010 ◽  
Vol 8 (2) ◽  
pp. 94
Author(s):  
Diogo Assed Bastos ◽  
Brenda Gumz ◽  
Frederico Costa ◽  
◽  
◽  
...  
Keyword(s):  
Neuroendocrine Tumours ◽  
Antitumour Activity ◽  
Somatostatin Receptors ◽  
Somatostatin Analogues ◽  
Antiangiogenic Activity ◽  
Tumour Shrinkage ◽  
Phosphotyrosine Phosphatases ◽  
Antitumour Effects

Neuroendocrine tumours (NETs) are rare and heterogeneous neoplasms that can present with functional syndromes due to the hypersecretion of peptides. Somatostatin analogues (SSAs) have been used since the 1980s for the treatment of neuroendocrine tumours, with the aim of controlling the symptoms of functioning tumours and improving patients’ quality of life. Data from preclinical studies offer evidence of both direct and indirect mechanisms by which SSAs can exert antitumour effects. The activation of somatostatin receptors by SSAs leads to the activation of phosphotyrosine phosphatases, which control downstream apoptotic and antiproliferation signalling pathways. Also, the suppression of secretion of several growth factors and inhibition of antiangiogenic activity by SSAs indirectly inhibits tumour cell proliferationin vitro. Previous uncontrolled studies had shown tumour shrinkage and disappearance in response to the SSA octreotide. Recent results from the randomised and placebo-controlled PROMID trial have demonstrated that octreotide has antitumour activity in patients with metastatic mid-gut NETs. This article examines recent data providing evidence of the antitumour activity of somatostatin analogues.

scholarly journals Contemporary Management of Clinically Non-functioning Pituitary Adenomas: A Clinical Review

2020 ◽  
Vol 13 ◽  
pp. 117955142093292
Author(s):  
Mussa H AlMalki ◽  
Maswood M Ahmad ◽  
Imad Brema ◽  
Khaled M AlDahmani ◽  
Nadeem Pervez ◽  
...  
Keyword(s):  
Pituitary Adenomas ◽  
Tumour Size ◽  
Somatostatin Receptor ◽  
Pituitary Surgery ◽  
Pituitary Tumours ◽  
Standardized Mortality Ratios ◽  
New Perspective ◽  
Contemporary Management ◽  
The Cost ◽  
Non Functioning Pituitary Adenomas

Non-functioning pituitary adenomas (NFPAs) are benign pituitary tumours that constitute about one-third of all pituitary adenomas. They typically present with symptoms of mass effects resulting in hypopituitarism, visual symptoms, or headache. Most NFPAs are macroadenomas (>1 cm in diameter) at diagnosis that can occasionally grow quite large and invade the cavernous sinus causing acute nerve compression and some patients may develop acute haemorrhage due to pituitary apoplexy. The progression from benign to malignant pituitary tumours is not fully understood; however, genetic and epigenetic abnormalities may be involved. Non-functioning pituitary carcinoma is extremely rare accounting for only 0.1% to 0.5 % of all pituitary tumours and presents with cerebrospinal, meningeal, or distant metastasis along with the absence of features of hormonal hypersecretion. Pituitary surgery through trans-sphenoidal approach has been the treatment of choice for symptomatic NFPAs; however, total resection of large macroadenomas is not always possible. Recurrence of tumours is frequent and occurs in 51.5% during 10 years of follow-up and negatively affects the overall prognosis. Adjuvant radiotherapy can decrease and prevent tumour growth but at the cost of significant side effects. The presence of somatostatin receptor types 2 and 3 (SSTR3 and SSTR2) and D2-specific dopaminergic receptors (D2R) within NFPAs has opened a new perspective of medical treatment for such tumours. The effect of dopamine agonist from pooled results on patients with NFPAs has emerged as a very promising treatment modality as it has resulted in reduction of tumour size in 30% of patients and stabilization of the disease in about 58%. Despite the lack of long-term studies on the mortality, the available limited evidence indicates that patients with NFPA have higher standardized mortality ratios (SMR) than the general population, with women particularly having higher SMR than men. Older age at diagnosis and higher doses of glucocorticoid replacement therapy are the only known predictors for increased mortality.

scholarly journals Somatostatin analogues effectiveness in non-functioning pituitary adenomas in comparison with acromegaly

2015 ◽  
Author(s):  
Jolanta Kunert-Radek ◽  
Natalia Bozena Zawada ◽  
Marek Pawlikowski ◽  
Hanna Pisarek ◽  
Maciej Radek
Keyword(s):  
Pituitary Adenomas ◽  
Somatostatin Analogues ◽  
Non Functioning Pituitary Adenomas

scholarly journals Dopamine 2 and Somatostatin 1-5 Receptors Coexpression in Clinically Non-Functioning Pituitary Adenomas

2015 ◽  
pp. 369-377 ◽  
Author(s):  
F. GABALEC ◽  
M. DRASTIKOVA ◽  
T. CESAK ◽  
D. NETUKA ◽  
V. MASOPUST ◽  
...  
Keyword(s):  
Pituitary Adenomas ◽  
Somatostatin Receptors ◽  
High Expression ◽  
Quantitative Real Time Pcr ◽  
Null Cell ◽  
Expression Ratio ◽  
Adenoma Tissue ◽  
Dopamine 2 Receptor ◽  
Corticotroph Adenomas ◽  
Non Functioning Pituitary Adenomas

This study investigated quantitated expression of dopamine 2 receptor (D2R) and somatostatin receptors of the five types (SSTR1-SSTR5) in a large series of clinically non-functioning pituitary adenomas (CNFAs). Co-expression of these receptors in individual adenomas was studied as well as correlation between receptor types. Adenoma tissue from 198 patients who underwent surgery for CNFAs was analyzed by immunohistochemistry and quantitative real-time PCR. D2R and SSTR1-3 mRNA was expressed in all 198 adenomas. SSTR4 and SSTR5 were detectable in 85 % and 61 % of adenomas, respectively. Expression of D2R was significantly higher than that of the somatostatin receptors. The median relative expressions were as follows from highest D2R >> SSTR3 > SSTR2 > SSTR1 > SSTR5 > SSTR4. High relative expression (ratio to β-glucuronidase mRNA > 1) of D2R was found in 60 % of tumors, high expression of SSTR1 in 7.5 %, SSTR2 in 7 %, SSTR3 in 4 % and SSTR5 in 0.5 %. The quantity of D2R correlated positively with expression of SSTR2 and SSTR3, and negatively with SSTR1 and SSTR5. Among histological adenoma types, SSTR1 was significantly higher in null-cell adenomas and SSTR3 was lower in silent corticotroph adenomas. In conclusions, in CNFAs, high expression of somatostatin receptors is much less common than that of D2R, and co-expression of both these receptors is exceptional. D2R and SSTR3 seem to be the most promising targets for pharmacological treatment.

Sign in / Sign up

Export Citation Format

Share Document