Use of CEST (Chemical Exchange Saturation Transfer) Imaging in PET/MRI

Study Overview
=================
Brief Summary
-----------------
Standard Magnetic Resonance Imaging (MRI) is based on the excitation of hydrogen nuclei that are presents in water molecules, which abundance in human body allows for obtention of superior contrast. However, assessing the presence of other molecules than water in tissues is also of great clinical interest to probe metabolites related to physiological body function and pathological conditions. Chemical exchange saturation transfer (CEST) allow to overcome some limitations of proton magnetic resonance spectroscopy (1H-MRS) by exploiting chemical properties of the targeted molecule through a continuous process of re-saturation and exchange, and thus detecting it with increased sensitivity, from two orders of magnitude. Moreover, CEST technique is based on imaging sequences and can therefore benefit from well-known fast acquisition strategies, as well as improved spatial resolution.

Detailed Description
-----------------
For this study the investigators propose to include an additional CEST sequence in standard PET/MRI exam in order to obtain a cartography with biochemical informations from tissues in patients with glioma or brain metastases.

Official Title
-----------------
Use of CEST (Chemical Exchange Saturation Transfer) Imaging in PET/MRI

Conditions
-----------------
Glioma, Brain Metastases

Intervention / Treatment
-----------------
* Other: Additional CEST sequences during PET/MRI exam


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients admitted to the Nuclear Medicine and Molecular Imaging department of ICANS (Institut de cancérologie strasbourg Europe) for a PET/MRI exam dedicated to: Preoperative evaluation of a cerebral expansion lesion Evaluation of glioma recurrences Evaluation of brain metastases Evaluation of recurrence of metastases Exclusion Criteria: Contraindication to the realization of an MRI Minor or patients placed under guardianship or supervision Patients deprived of liberty Patients placed under judicial protection Patients that are not able to express their consent Pregnant and breastfeeding women

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Patients with glioma or brain metastases<br> | Other: Additional CEST sequences during PET/MRI exam<br>* CE-Marked Advanced Technology Software Modules (ATSM) for Magnetic Resonance Imaging from General Electric Healthcare<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Obtention, from a set of brain PET-MRI images, of an intratissular pH mapping in patients with glioma or brain metastases | Evaluation at the cerebral level on the acquisition images of residual volume in MRI | through study completion, up to 14 years | 
| Obtention, from a set of brain PET-MRI images, of an intratissular pH mapping in patients with glioma or brain metastases | Evaluation at the cerebral level on the acquisition images of tumoral metabolic activity in PET | through study completion, up to 14 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlate intratissular pH mapping and location of recurrence |  | through study follow-up, up to 10 years | 
| Correlate average pH of the tumor and histopathology |  | through study follow-up, up to 10 years | 
| Correlate average pH of the tumor and Disease-Free Survival (DFS) |  | through study follow-up, up to 10 years | 
| Correlate average pH of the tumor and Overall survival (OS) |  | through study follow-up, up to 10 years |