Dual Tracer (68Ga-DOTATATE and 18F-FDG) PET Imaging in G2 & G3 Gastroenteropancreatic Neuroendocrine Tumors

NCT04804371 | Active Not Recruiting

• 1 other identifier: 20-5920
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

The variable clinical outcome of patients with G2 \& G3 well diff GEP-NETs makes the selection of an optimal treatment strategy challenging. Initial data suggests that high DOTATATE uptake and low FDG uptake are suggestive of low grade disease, with an indolent course. Conversely, low DT uptake and high FDG uptake are suggestive of high-grade/ aggressive disease. G2/3 GEP NETs may be biologically diverse; clinically relevant cohort for dual-tracer PET imaging. Our secondary objectives are

1. 1.To determine the distribution of PETNET scores derived from 18F-FDG \& 68Ga-DT PET in patients with G2 \& G3 well diff GEP-NETs.
2. 2.To determine the proportion of patients in whom the addition of 18F-FDG PET data results in a change in planned clinical management.

Conditions

Neuroendocrine Tumors

Outcome Measures

Primary Outcomes (2)

• Discordance in tracer uptake:

  Discordance in tracer uptake as assessed by PETNET score distribution: Proportion of patients with PETNET score of P1/P2 (no or low FDG uptake) vs those with P3-P5 (moderate or high FDG uptake).

  2 years

• Impact to patient management:

  Impact of the addition of FDG PET to patient management as assessed by rate of clinical management changed after the addition of 18F-FDG PET/CT to 68Ga-DOTATATE PET/CT.

  2 years

Secondary Outcomes (3)

• Intraindividual tumor heterogeneity:

  2 years

• Tumor texture geatures as predictors of tumor grade:

  2 years

• Tumor texture features as predictors of tumor metabolism and somatostatin receptor expression:

  2 years

Study Arms (1)

18F-FDG PETCT scan

OTHER

18F-FDG tracer (5 MBq/kg body weight of FDG; up to 550 MBq) will be injected into the intravenous

Drug: F18-FDG

Interventions

F18-FDG DRUG

Evaluate FDG uptake

18F-FDG PETCT scan

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Has provided written informed consent prior to any study-related procedures,
• Is a male or a female of 18 years of age or older.
• Patients who already had/scheduled for a 68Ga-DOTATATE PET/CT scan.
• Has a gastro entero-pancreatic neuroendocrine neoplasm confirmed by histological criteria. Patients with unknown primaries clinically thought to be from gastroenteropancreatic source shall be eligible.
• Has a well differentiated tumour Grade 2-3 (WHO 2017).
• Has a tumour with a proliferation index (Ki67 ≥3%) or in samples where the Ki67 antigen cannot be reliably quantified, a mitotic index ≥2 mitosis/10HPF (high power fields)
• Treatment naïve patients and/or patient who have received any number of prior systemic therapy lines for metastatic disease and/or locally advanced inoperable tumor.
• Willing and able to comply with all study requirements, including timing and/or nature of required assessments.
• Women of child-bearing age will undergo a urine test to exclude pregnancy prior to PET.

You may not qualify if:

• Patients with known lung neuroendocrine tumours or other proven non gastroenteropancreatic histologies are not eligible.
• Patients with any known hypersensitivity to FDG.
• Has a well differentiated neuroendocrine tumour Grade 1 (WHO 2017).
• Has a poorly differentiated neuroendocrine carcinoma (WHO 2017).
• Mixed neuroendocrine and non-neuroendocrine cancer
• Has any mental condition rendering the patient unable to understand the nature, scope and possible consequences of the study, and/or evidence of an uncooperative attitude.
• Any patient who is pregnant.

Sponsors & Collaborators

• University Health Network, Toronto: lead
• Canadian Neuroendocrine Tumour Society (CNETS): collaborator

Study Sites (1)

Princess Margaret Cancer Centre

Toronto, Ontario, M5G 2M9, Canada

Location

MeSH Terms

Conditions

Neuroendocrine Tumors

Condition Hierarchy (Ancestors)

Neuroectodermal Tumors; Neoplasms, Germ Cell and Embryonal; Neoplasms by Histologic Type; Neoplasms; Neoplasms, Nerve Tissue

Study Officials

• Ur Metser, MD

  University Health Network, Toronto

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Histologically proven well diff GEP NET, G2-3, Ki 67 ≥3% (or mitotic index ≥2 mitosis/10HPF).

Study Record Dates

• First Submitted: March 3, 2021
• First Posted: March 18, 2021
• Study Start: March 4, 2021
• Primary Completion (Estimated): February 22, 2027
• Study Completion (Estimated): February 22, 2027
• Last Updated: March 23, 2026

Record last verified: 2026-03

Locations

CA (1)