68Ga-DOTA-TATE PET/CT for Molecular Imaging of Somatostatin Receptor Expression in Metastasizing Chordoma

The heterogeneous nature of the neuroendocrine tumors (NET) makes it challenging to find one uniformly applicable management protocol which is especially true for diagnosis. The discovery of the overexpression of somatostatin receptors (SMS-R) on neuroendocrine tumor cells lead to the generalized and rapid acceptance of radiolabeled somatostatin receptor analogs for staging and restaging of NET as well as for Peptide Receptor Radionuclide Therapy (PRRNT) using Y-90 and Lu-177 DOTATATE/DOTATOC. In this present work we tried to look in to the effect of PRRNT on the glucose metabolism assessed by F-18 FDG PET/CT and SMS-R density assessed by Ga-68 DOTANOC PET/CT. We observed a complex relationship between the somatostatin receptor expression and glucose metabolism with only 56% (77/138) of the lesions showing match, while the others show mismatch between the receptor status and metabolism. The match between receptor expression and glucose metabolism increases with the grade of NET. In grade 3 NET, there is a concurrence between the changes in glucose metabolism and somatostatin receptor expression. PRRNT was found to be more effective in lesions with higher receptor expression.

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Recent Updates on Molecular Imaging Reporting and Data Systems (MI-RADS) for Theranostic Radiotracers—Navigating Pitfalls of SSTR- and PSMA-Targeted PET/CT

Journal of Clinical Medicine ◽

10.3390/jcm8071060 ◽

2019 ◽

Vol 8 (7) ◽

pp. 1060 ◽

Cited By ~ 5

Author(s):

Rudolf A. Werner ◽

James T. Thackeray ◽

Martin G. Pomper ◽

Frank M. Bengel ◽

Michael A. Gorin ◽

...

Keyword(s):

Molecular Imaging ◽

Somatostatin Receptor ◽

False Negative ◽

Treatment Strategies ◽

Current Treatment ◽

Subsequent Treatment ◽

Targeted Imaging ◽

Data Systems ◽

Pet Ct ◽

Framework System

The theranostic concept represents a paradigmatic example of personalized treatment. It is based on the use of radiolabeled compounds which can be applied for both diagnostic molecular imaging and subsequent treatment, using different radionuclides for labelling. Clinically relevant examples include somatostatin receptor (SSTR)-targeted imaging and therapy for the treatment of neuroendocrine tumors (NET), as well as prostate-specific membrane antigen (PSMA)-targeted imaging and therapy for the treatment of prostate cancer (PC). As such, both classes of radiotracers can be used to triage patients for theranostic endoradiotherapy using positron emission tomography (PET). While interpreting PSMA- or SSTR-targeted PET/computed tomography scans, the reader has to navigate certain pitfalls, including (I.) varying normal biodistribution between different PSMA- and SSTR-targeting PET radiotracers, (II.) varying radiotracer uptake in numerous kinds of both benign and malignant lesions, and (III.) resulting false-positive and false-negative findings. Thus, two novel reporting and data system (RADS) classifications for PSMA- and SSTR-targeted PET imaging (PSMA- and SSTR-RADS) have been recently introduced under the umbrella term molecular imaging reporting and data systems (MI-RADS). Notably, PSMA- and SSTR-RADS are structured in a reciprocal fashion, i.e., if the reader is familiar with one system, the other system can readily be applied. Learning objectives of the present case-based review are as follows: (I.) the theranostic concept for the treatment of NET and PC will be briefly introduced, (II.) the most common pitfalls on PSMA- and SSTR-targeted PET/CT will be identified, (III.) the novel framework system for theranostic radiotracers (MI-RADS) will be explained, applied to complex clinical cases and recent studies in the field will be highlighted. Finally, current treatment strategies based on MI-RADS will be proposed, which will demonstrate how such a generalizable framework system truly paves the way for clinically meaningful molecular imaging-guided treatment of either PC or NET. Thus, beyond an introduction of MI-RADS, the present review aims to provide an update of recently published studies which have further validated the concept of structured reporting systems in the field of theranostics.

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Positive Somatostatin Receptor Expression Demonstrated on 68Ga-NODAGA-LM3 PET/CT in a Neuroendocrine Tumor Patient With Negative Immunohistochemical Staining

Clinical Nuclear Medicine ◽

10.1097/rlu.0000000000003653 ◽

2021 ◽

Vol Publish Ahead of Print ◽

Author(s):

Wenjia Zhu ◽

Rongrui Liu ◽

Lin Zhao ◽

Li Huo

Keyword(s):

Neuroendocrine Tumor ◽

Immunohistochemical Staining ◽

Somatostatin Receptor ◽

Receptor Expression ◽

Tumor Patient ◽

Pet Ct

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68Ga-DOTATATE PET in Pediatric Paraganglioma / Pheochromocytoma: A Case-series Highlighting the Role of Functional Imaging

10.22541/au.163892838.81775782/v1 ◽

2021 ◽

Author(s):

Aleksandra Augustynowicz ◽

Neha Kwatra ◽

Laura Drubach ◽

Christopher Weldon ◽

Katherine Janeway ◽

...

Keyword(s):

Functional Imaging ◽

Imaging Techniques ◽

Somatostatin Receptor ◽

Case Series ◽

Response Assessment ◽

Receptor Expression ◽

Imaging Modalities ◽

Nuclear Medicine Imaging ◽

Decision Algorithm ◽

Pet Ct

Pheochromocytoma and paraganglioma (PPGL) are rare neuroendocrine tumors in childhood. Cancer predisposition syndromes (CPS) are increasingly recognized as the underlying cause for a number of pediatric malignancies and up to 40% of PPGL are currently thought to be associated with a hereditary predisposition1,2. With the increasingly widespread availability of functional molecular imaging techniques, nuclear medicine imaging modalities such as 18F-FDG-PET/CT, 123I-MIBG SPECT/CT, and 68Ga-DOTATATE PET/CT now play an essential role in the staging, response assessment and determination of suitability for targeted radiotherapy in patients with PPGL. Each of these imaging modalities targets a different cellular characteristic, such as glucose metabolism (FDG), norepinephrine transporter expression (MIBG), or somatostatin receptor expression (DOTATATE), and therefore can be complementary to anatomic imaging and to each other. Given the recent FDA approval3 and increasing use of 68Ga-DOTATATE for imaging in children4, the purpose of this article is to use a case-based approach to highlight both the advantages and limitations of DOTATATE imaging as it compares to current radiologic imaging techniques in the staging and response assessment of pediatric PPGL, and to offer a decision algorithm for the use of functional imaging that can be applied to PPGL, as well as other neuroendocrine malignancies.

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Gallium-68 DOTATOC PET/CT In Vivo Characterization of Somatostatin Receptor Expression in the Prostate

Cancer Biotherapy & Radiopharmaceuticals ◽

10.1089/cbr.2013.1570 ◽

2014 ◽

Vol 29 (3) ◽

pp. 108-115 ◽

Cited By ~ 11

Author(s):

Mila V. Todorović-Tirnanić ◽

Milan M. Gajić ◽

Vladimir B. Obradović ◽

Richard P. Baum

Keyword(s):

Somatostatin Receptor ◽

Receptor Expression ◽

Pet Ct ◽

Gallium 68 ◽

In Vivo Characterization

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68Ga-DOTATOC PET/CT-Based Radiomic Analysis and PRRT Outcome: A Preliminary Evaluation Based on an Exploratory Radiomic Analysis on Two Patients

Frontiers in Medicine ◽

10.3389/fmed.2020.601853 ◽

2021 ◽

Vol 7 ◽

Author(s):

Virginia Liberini ◽

Osvaldo Rampado ◽

Elena Gallio ◽

Bruno De Santi ◽

Francesco Ceci ◽

...

Keyword(s):

Pearson Correlation ◽

Somatostatin Receptor ◽

Principal Component ◽

Receptor Expression ◽

Whole Body ◽

Poor Correlation ◽

Preliminary Evaluation ◽

Whitney Test ◽

Mann Whitney Test ◽

Pet Ct

Aim: This work aims to evaluate whether the radiomic features extracted by 68Ga-DOTATOC-PET/CT of two patients are associated with the response to peptide receptor radionuclide therapy (PRRT) in patients affected by neuroendocrine tumor (NET).Methods: This is a pilot report in two NET patients who experienced a discordant response to PRRT (responder vs. non-responder) according to RECIST1.1. The patients presented with liver metastasis from the rectum and pancreas G3-NET, respectively. Whole-body total-lesion somatostatin receptor-expression (TLSREwb-50) and somatostatin receptor-expressing tumor volume (SRETV wb-50) were obtained in pre- and post-PRRT PET/CT. Radiomic analysis was performed, extracting 38 radiomic features (RFs) from the patients' lesions. The Mann–Whitney test was used to compare RFs in the responder patient vs. the non-responder patient. Pearson correlation and principal component analysis (PCA) were used to evaluate the correlation and independence of the different RFs.Results: TLSREwb-50 and SRETVwb-50 modifications correlate with RECIST1.1 response. A total of 28 RFs extracted on pre-therapy PET/CT showed significant differences between the two patients in the Mann–Whitney test (p < 0.05). A total of seven second-order features, with poor correlation with SUVmax and PET volume, were identified by the Pearson correlation matrix. Finally, the first two PCA principal components explain 83.8% of total variance.Conclusion: TLSREwb-50 and SRETVwb-50 are parameters that might be used to predict and to assess the PET response to PRRT. RFs might have a role in defining inter-patient heterogeneity and in the prediction of therapy response. It is important to implement future studies with larger and more homogeneous patient populations to confirm the efficacy of these biomarkers.

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Better way to image and manage Neuroendocrine Tumours: Role of 68Gallium DOTA-Peptide PET-CT scan

Bangladesh Journal of Nuclear Medicine ◽

10.3329/bjnm.v20i2.37400 ◽

2018 ◽

Vol 20 (2) ◽

pp. 136

Author(s):

Shankar Kumar Dey

Keyword(s):

Molecular Imaging ◽

Ct Scan ◽

Significant Role ◽

Neuroendocrine Tumours ◽

Somatostatin Receptor ◽

Somatostatin Receptors ◽

Somatostatin Analogues ◽

Pet Ct ◽

Receptor Scintigraphy ◽

Pet Ct Scan

Neuroendocrine tumours (NETs) are special entity of neoplasms arising from nervous and endocrine systems and involving variety of organs. Over expression of somatostatin receptors is an unique characteristic of these tumours. This allows molecular imaging to play a significant role in evaluation of NETs using somatostatin analogues. 111 In Pentetreotide scintigraphy has been playing a significant role as molecular imaging of choice to locate the primary tumor, evaluate extent of disease and plan for surgical management. Recently 68 Ga labelled peptides have emerged as promising PET tracers for scintigraphy of these tumours. Several recent studies have demonstrated the superiority of 68Ga DOTA- Peptide PET-CT scan with a number of advantages over conventional somatostatin receptor scintigraphy.Bangladesh J. Nuclear Med. 20(2): 136-142, July 2017

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