Immunohistochemical analysis of somatostatin receptor 2 (SSTR2) provides important information regarding the potential therapeutic efficacy of somatostatin analogues (SSAs) in patients with neuroendocrine tumors. HER2 scoring has been proposed to interpret SSTR2 immunoreactivity but their reproducibility was relatively low because of its intrinsic subjective nature. Digital image analysis (DIA) has recently been proposed as an objective and more precise method of evaluating immunoreactivity. Therefore, in this study, we used DIA for analyzing SSTR2 immunoreactivity in pancreatic neuroendocrine tumors (PanNETs) to obtain its H score and "(%) strong positive cells" and compared the results with those of manually obtained HER2 scores. Membranous SSTR2 immunoreactivity evaluated by DIA was calculated by two scales as: "Membrane Optical Density" and "Minimum Membrane Completeness". PanNETs with HER2 score of > 2 demonstrated the highest concordance with results of "(%) strong positive cells" obtained by DIA when "Minimum Membrane Completeness" was tentatively set at 80%. The SSTR2 immunoreactivity, evaluated based on all scoring systems, was different between grades G1 and G2 in insulinoma but not in non-functional PanNETs. DIA provided reproducible results of SSTR2 immunoreactivity in PanNETs and yielded important information as to the potential application of SSAs.

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00795-021-00294-6DOI Listing

Publication Analysis

Top Keywords

sstr2 immunoreactivity
20
neuroendocrine tumors
12
digital image
8
image analysis
8
analysis somatostatin
8
somatostatin receptor
8
pancreatic neuroendocrine
8
strong positive
8
positive cells"
8
immunoreactivity evaluated
8

Similar Publications

Digital quantification of somatostatin receptor subtypes 2 and 5 in growth hormone-secreting pituitary tumors.

Eur J Endocrinol

January 2025

Endocrinology Unit, Department of Internal Medicine and Medical Specialties (DIMI), University of Genova, 16132 Genova, Italy.

Immunohistochemistry (IHC) of somatostatin receptor subtype 2 can predict response to first-generation somatostatin receptor ligands (fg-SRLs) in acromegaly. Recently, we validated an open-source digital image analysis (DIA) to quantify somatostatin receptor subtype 2 (SSTR2) expression. We aimed to validate the DIA also on somatostatin receptor subtype 5 (SSTR5) in a new cohort of growth hormone (GH)-secreting pituitary tumors, with IHC performed in a different laboratory, and to correlate fg-SRL response with SSTs expression.

View Article and Find Full Text PDF

Metastatic pheochromocytomas and paragangliomas (PPGLs) are rare endocrine malignancies with limited effective treatment options. The association between the tumor microenvironment (TME) with somatostatin receptor 2 (SSTR2) and hypoxia-induced factor-2α (HIF-2α) in PPGLs, critical for optimizing combination therapeutic strategies with immunotherapy, remains largely unexplored. To evaluate the association of SSTR2 and HIF-2α immunoreactivity with the TME in patients with PPGLs, we analyzed the expression of SSTR2A, HIF-2α, and TME components, including tumor-infiltrating lymphocytes (CD4 and CD8), tumor-associated macrophages (CD68 and CD163), and PD-L1, using immunohistochemistry in patients with PPGLs.

View Article and Find Full Text PDF

Metastatic Pheochromocytoma and Paraganglioma: Somatostatin Receptor 2 Expression, Genetics, and Therapeutic Responses.

J Clin Endocrinol Metab

September 2023

Department of Endocrinology, Diabetology and Clinical Nutrition, University Hospital Zurich (USZ), and University of Zurich (UZH), CH-8091 Zurich, Switzerland.

Article Synopsis
  • Pheochromocytomas and paragangliomas (PPGLs) with mutations in the SDHB gene have a high risk of metastasis, and SSTR2-dependent imaging is the most effective way to detect these tumors, indicating SSTR2 as a key therapeutic biomarker.
  • A study analyzed data from 202 PPGL patients across multiple centers to assess the relationship between SSTR2 and SDHB expression, mutation status, and clinical behavior.
  • Results showed that half of the patients had SSTR2 positivity, which correlated with SDHB mutations and metastatic disease, highlighting the effectiveness of SSTR-based therapies in controlling the disease in metastatic cases.
View Article and Find Full Text PDF

Somatostatin receptor 2 (), the most abundant receptor of somatostatin (), possesses immunoreactivity and is altered in many cancers. However, the association between and efficacy of immune checkpoint inhibitors (ICIs) has not yet been reported. Immunohistochemistry (IHC) information across 20 cancers was collected from the Human Protein Atlas (HPA) and used to analyze the expression of .

View Article and Find Full Text PDF

Somatostatin analogues (SSAs) are widely used to treat gastroenteropancreatic neuroendocrine tumors (GEP-NETs). Somatostatin receptor 2 (SSTR2) immunoreactivity serves as a predictive marker of the therapeutic efficacy of SSAs in pancreatic NETs. However, SSTR2 expression profiles in tumor cells and their association with the therapeutic efficacy of SSAs remains virtually unknown in gastrointestinal NETs (GI-NETs).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!