Dataset Information

Correlation of Somatostatin Receptor 1-5 Expression, [⁶⁸Ga]Ga-DOTANOC, [¹⁸F]F-FDG PET/CT and Clinical Outcome in a Prospective Cohort of Pancreatic Neuroendocrine Neoplasms.

ABSTRACT:

Purpose

The aim of this study was to correlate immunohistochemical (IHC) tissue levels of SSTR1-5 with the receptor density generated from [⁶⁸Ga]Ga-DOTANOC uptake in a prospective series of NF-PNENs.

Methods

Twenty-one patients with a total of thirty-five NF-PNEN-lesions and twenty-one histologically confirmed lymph node metastases (LN+) were included in this prospective study. Twenty patients were operated on, and one underwent endoscopic ultrasonography and core-needle biopsy. PET/CT with both [⁶⁸Ga]Ga-DOTANOC and [¹⁸F]F-FDG was performed on all patients. All histological samples were re-classified and IHC-stained with monoclonal SSTR1-5 antibodies and Ki-67 and correlated with [⁶⁸Ga]Ga-DOTANOC and [¹⁸F]F-FDG PET/CT.

Results

Expression of SSTR1-5 was detected in 74%, 91%, 80%, 14%, and 77% of NF-PNENs. There was a concordance of SSTR2 IHC with positive/negative [⁶⁸Ga]Ga-DOTANOC finding (Spearman's rho 0.382, p = 0.043). All [⁶⁸Ga]Ga-DOTANOC-avid tumors expressed SSTR2 or SSTR3 or SSTR5. Expression of SSTR5 was higher in tumors with a low Ki-67 proliferation index (PI) (-0.353, 95% CI -0.654-0.039, p = 0.038). The mean Ki-67 PI for SSTR5 positive tumors was 2.44 (SD 2.56, CI 1.0-3.0) and 6.38 (SD 7.25, CI 2.25-8.75) for negative tumors.

Conclusion

SSTR2 was the only SSTR subtype to correlate with [⁶⁸Ga]Ga-DOTANOC PET/CT. Our prospective study confirms SSTR2 to be of the highest impact for SST PET/CT signal.

SUBMITTER: Majala S

PROVIDER: S-EPMC8750461 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:The trend to inform personalized molecular radiotherapy with molecular imaging diagnostics, a concept referred to as theranostics, has transformed the field of nuclear medicine in recent years. The development of theranostic pairs comprising somatostatin receptor (SSTR)-targeting nuclear imaging probes and therapeutic agents for the treatment of patients with neuroendocrine tumors (NETs) has been a driving force behind this development. With the Neuroendocrine Tumor Therapy (NETTER-1) phase 3 trial reporting encouraging results in the treatment of well-differentiated, metastatic midgut NETs, peptide radioligand therapy (RLT) with the 177Lu-labeled somatostatin analog (SSA) [177Lu]Lu-DOTA-TATE is now anticipated to become the standard of care. On the diagnostics side, the field is currently dominated by 68Ga-labeled SSAs for the molecular imaging of NETs with positron emission tomography-computed tomography (PET/CT). PET/CT imaging with SSAs such as [68Ga]Ga-DOTA-TATE, [68Ga]Ga-DOTA-TOC, and [68Ga]Ga-DOTA-NOC allows for NET staging with high accuracy and is used to qualify patients for RLT. Driven by the demand for PET/CT imaging of NETs, a commercial kit for the production of [68Ga]Ga-DOTA-TATE (NETSPOT) was approved by the U.S. Food and Drug Administration (FDA). The synthesis of 68Ga-labeled SSAs from a 68Ge/68Ga-generator is straightforward and allows for a decentralized production, but there are economic and logistic difficulties associated with these approaches that warrant the search for a viable, generator-independent alternative. The clinical introduction of an 18F-labeled SSTR-imaging probe can help mitigate the shortcomings of the generator-based synthesis approach, but despite extensive research efforts, none of the proposed 18F-labeled SSAs has been translated past prospective first-in-humans studies so far. Here, we review the current state of probe-development from a translational viewpoint and make a case for a clinically viable, 18F-labeled alternative to the current standard [68Ga]Ga-DOTA-TATE.

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Dataset Information

Correlation of Somatostatin Receptor 1-5 Expression, [⁶⁸Ga]Ga-DOTANOC, [¹⁸F]F-FDG PET/CT and Clinical Outcome in a Prospective Cohort of Pancreatic Neuroendocrine Neoplasms.

Purpose

Methods

Results

Conclusion

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Dataset Information

Correlation of Somatostatin Receptor 1-5 Expression, [68Ga]Ga-DOTANOC, [18F]F-FDG PET/CT and Clinical Outcome in a Prospective Cohort of Pancreatic Neuroendocrine Neoplasms.

Purpose

Methods

Results

Conclusion

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Correlation of Somatostatin Receptor 1-5 Expression, [⁶⁸Ga]Ga-DOTANOC, [¹⁸F]F-FDG PET/CT and Clinical Outcome in a Prospective Cohort of Pancreatic Neuroendocrine Neoplasms.