Whole Body Dynamic 68Ga-DOTATOC PET/CT in Neuroendocrine Tumors (GAPET-NET)

Prognostic Interest of a Whole Body Dynamic PET Acquisition in Pre-therapeutic 68Ga-DOTATOC PET/CT for Neuroendocrine Tumors

Neuroendocrine tumors (NET) are a network of rare tumors with common embryological origin. Functional imaging plays a major role in the extension assessment and tumor characterization of NETs. SPECT/CT with 111In-pentetreotide is the recommended test when tumors are well differentiated (grade G1 or G2). It has a real interest in diagnosis, in therapeutic decision-making (in particular by cold somatostatin analogues or in PRRT) and in the systematic follow-up of patients. Nevertheless, SPECT/CT procedure makes for a relatively long review. In addition, scintigraphy has a lower spatial resolution than PET technology and remains of limited interest for signal quantification.

However, the ability to locate and quantitatively measure the absorption of radiopharmaceuticals in the target tissues is a major challenge in oncology for the characterization of the disease.

Recent developments in radiopharmacy have made it possible to target NETs in PET imaging through the use of somatostatin analogues coupled with positron emitters, called 68Ga-DOTA peptides. The diagnostic performance of 68Ga-DOTApeptide PET/CT appears to be superior to SPECT/CT with 111In-pentetreotide. A marketing authorization has thus recently been issued in France for the use of 68Ga-DOTATOC.

Historically, the recommended quantification method in PET was based on the instantaneous measurement in static acquisition (3D) of the maximum of the standardized uptake value (SUVmax). This approach has the disadvantage to measure the signal at a time "t" for a single voxel of the image. Dynamic acquisition methods (4D) have been proposed to extract a radiotracer absorption coefficient (Ki) for a lesion. Several studies have demonstrated the superiority of Ki versus SUVmax in 18FDG PET/CT for the diagnostic management, therapeutic evaluation and prognosis of various solid cancers.

However, no work has validated this approach in PET / CT at 68Ga-DOTATOC as part of the prognostic evaluation of NETs.

The objective of the study is to evaluate the prognostic value of the tumor absorption coefficient Ki resulting from a 4D whole-body dynamic acquisition in PET / CT at 68Ga-DOTATOC in patients with well-differentiated NETs grade I or II according to the WHO classification

Study Overview

• Status: Recruiting
• Conditions: Neuroendocrine Tumors
• Intervention / Treatment: Device: Whole Body Dynamic 68Ga-DOTATOC PET/CT

• Study Type: Observational
• Enrollment (Anticipated): 120

Contacts and Locations

• Study Contact: Name: Philippe Thuillier; Phone Number: 02-98-34-71-19; Email: philippe.thuillier@chu-brest.fr
• Study Contact Backup: Name: Ronan Abgral

Study Locations

• France
  • Brest, France, 29609
    • Recruiting
    • CHRU de Brest
    • Contact: Philippe Thuillier; Phone Number: 02-98-34-71-19

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 100 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: N/A
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients with NET histologically proven and presented in RCP RENATEN at CHRU Brest Primitive: Gastroenteropancreatic, bronchopulmonary or unknown

Description

Inclusion Criteria:

• Patient majeur ≥ 18 year old
• Présenting a well differentiated neuroendocrine tumor (G1 ou G2)
• Indication performing a68Ga-DOTATOC PET/CT
• non-opposition

Exclusion Criteria:

• Patient <18 years old
• Breastfeeding/ pregnancy
• Other type of tumor
• Refusal of participation

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Progression free survival (PFS)	To evaluate the prognostic value of lesionnal Ki on progression-free survival at 2 years and compare it with SUVmax (static 3D acquisition) in patients with metastatic well-differentiated NET	2 years
Recidive free survival (RFS)	To evaluate the prognostic value of Ki lesion on progression-free survival at 2 years and compare it with SUVmax (static 3D acquisition) in patients with localised well-differentiated NET	2 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Correlation between lesionnal Ki and immunochemistry markers	Evaluate the statistical correlation between lesional Ki versus SUVmax with NET immunohistochemistry markers expression (SSTR2, SSTR3, and SSTR5; BCL2, Phospho-MTOR expression PD-L1 by tumor cells and immune cells, intra-tumor CD8 + lymphocytes, tumor necrosis surface)	0 to 2 years
Predictive value of non-event survival (PFS+RFS)	To evaluate the predictive value of non-event survival (PFS+RFS) with a ΔKi approach in patients receiving an intermediate therapeutic assessment examination (somatostatin analogues or PRRT with 177Lu-DOTATATE), and compare it with a ΔSUVmax approach	6 months to 2 years
Correlation between 68Ga-DOTATOC PET/CT and/or 111In-pentetréotide SPECT/CT and 177Lu-DOTATATE SPECT/CT	Evaluate the statistical correlation between the SUVmax assessed with 68Ga-DOTATOC PET/CT and/or 111In-pentetréotide SPECT/CT and 177Lu-DOTATATE SPECT/CT	0 to 2 years
Prognostic value of Ki versus usual prognostic parameters	To evaluate the prognostic value on non-event survival (PFS+RFS) at 2 years of Ki and clinical parameters (sex, age), biological (CgA assay), pathology (grade, differentiation, Ki67 expression, BCL2, phospho-MTOR).	2 years

Collaborators and Investigators

• Sponsor: University Hospital, Brest

Study record dates

Study Major Dates

• Study Start (ACTUAL): July 19, 2018
• Primary Completion (ANTICIPATED): July 1, 2023
• Study Completion (ANTICIPATED): July 1, 2023

Study Registration Dates

• First Submitted: June 22, 2018
• First Submitted That Met QC Criteria: June 22, 2018
• First Posted (ACTUAL): July 3, 2018

Study Record Updates

• Last Update Posted (ACTUAL): July 18, 2019
• Last Update Submitted That Met QC Criteria: July 16, 2019
• Last Verified: July 1, 2019

More Information

Terms related to this study

• Keywords: Positron Emission Tomography Computed Tomography; Gallium 68; whole body dynamic acquisition
• Additional Relevant MeSH Terms: Neoplasms by Histologic Type; Neoplasms; Neuroectodermal Tumors; Neoplasms, Germ Cell and Embryonal; Neoplasms, Nerve Tissue; Neuroendocrine Tumors; Molecular Mechanisms of Pharmacological Action; Radiopharmaceuticals; Edotreotide
• Other Study ID Numbers: GAPET-NET (29BRC17.0036)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: All collected data that underlie results in a publication
• IPD Sharing Time Frame: Data will be available after the publication of result and ending three years maximum following the last visit of the last patient
• IPD Sharing Access Criteria: Data access requests will be reviewed by the internal committee of Brest UH. requestors will be required to sign and complete a data access agreement
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No