Somatostatin Receptor Subtype Expression in Patients with Acromegaly and Complicated Clinical Course.

Robert Pichler,Daniela Ehrlich,Ognian Kalev,Marina Hodolic,Michael Sonnberger,Berndt Tomancok

doi:10.3390/diagnostics11061050

Robert Pichler, Daniela Ehrlich + Show 4 more

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https://doi.org/10.3390/diagnostics11061050

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Abstract

Somatostatin analogues are considered to be the first line of treatment in acromegaly. Somatostatin analogues of the first generation mainly target the somatostatin receptor (SSTR) subtype 2 and have been proven efficient in the majority of patients with acromegaly. Pasireotide was the first somatostatin analogue also substantially targeting the SSTR subtype 5. An efficient drug for Cushing’s disease tailored to suboptimal-responding patients with acromegaly then became available. We immunohistochemically investigated SSTR subtypes expression in pituitary adenomas from operated acromegaly patients with clinical relapse and a complicated clinical course. Patients received pasireotide in the course of their disease. The predictive value of SSTR subtypes immunhistochemical analysis for the therapeutic response is discussed.

Highlights

Published: 7 June 2021Somatostatin analogues (SA) are a cornerstone in the treatment of acromegaly that have enabled efficient medical treatment since their introduction
It has been reported that high SSTR2 levels and SSTR2/SSTR5 ratio are associated with responsiveness to first generation somatostatin analogues—if not, pasireotide efficacy is favoured [3]
We investigated immunohistochemically somatostatin receptor (SSTR) subtypes 2 and 5 in pituitary adenomas in operated acromegaly patients with clinical relapse under treatment with SA of the first generation

Summary

Introduction

Published: 7 June 2021Somatostatin analogues (SA) are a cornerstone in the treatment of acromegaly that have enabled efficient medical treatment since their introduction. SA of the first generation, mainly targeting the somatostatin receptor (SSTR) subtype 2, has proven to be efficient in most patients with acromegaly but not in patients with Cushing’s disease. With the development of SA targeting the SSTR subtype 5 to the subtype 2, i.e., pasireotide, an efficient drug for ACTH secreting pituitary tumor patients became available [1]. Patients with acromegaly who could not be managed satisfactorily with sandostatin or lanreotide could reach endocrine control under pasireotide treatment [2]. It is feasible to investigate specific subtype-receptor density on biopsy specimens using immunohistochemistry methods; but it is not yet established to measure SSTR subtype. It has been reported that high SSTR2 levels and SSTR2/SSTR5 ratio are associated with responsiveness to first generation somatostatin analogues—if not, pasireotide efficacy is favoured [3]

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