Assessing 11C-Choline (11C-CH) PET to Distinguish True Tumor Progression From Pseudoprogression in High-grade Gliomas

Assessing 11C-Choline (11C-CH) PET to Distinguish True Tumor Progression From Pseudoprogression in High-grade Gliomas

Pilot Study of 11C-Choline (11C-CH) PET in Assessing Post-treatment True Tumor Progression From Pseudo-progression in High-grade Gliomas

This is a pilot study. The purpose of this study is to test if an imaging tracer, not approved by the FDA, called 11C-Choline (11C-CH) is useful for evaluating your type of cancer. This tracer is used to perform PET scans. The researchers want to see if the 11C-CH PET scan, using the study tracer 11C-CH, can improve upon the usual scans at diagnosing or monitoring your type of cancer. In patients with high-grade gliomas, changes on standard MRI of the brain may reflect true tumor growth or inflammatory changes in response to treatment, called pseudo-progression. It is important to distinguish true tumor growth from inflammation since inflammation indicates the tumor is responding to treatment. With standard MRI, it is difficult to determine if changes following treatment are due to tumor growth or inflammation early on. Researchers hope to learn if the investigational tracer, 11C-CH, will be able to distinguish true tumor growth from inflammation more accurately than standard MRI or 18F-FDG PET scans.

Eligible patients must have undergone standard radiation (typically 60Gy in 30 fractions), with or without concurrent drug therapy, and have MRI findings consistent with tumor progression and/or pseudoprogression within 24 weeks after completion of radiation. Eligible patients will undergo an 11C-CH PET study within 2 weeks of the standard of care MRI that shows changes concerning for tumor progression vs. pseudoprogression. All patients will then be followed with surveillance brain MRI with and without contrast as per standard of care for a period of 11 months, to assess further progression or stabilization of the lesion. Initial MRI changes are considered to represent pseudoprogression/treatment related changes if the lesion stabilizes or becomes smaller without a change in tumor-related therapy. Otherwise, it will be considered a recurrence should there be progessive radiographic changes.

from 11C-CH PET with evolving changes on brain MRI in high-grade glioma after radiotherapy. In a small subgroup of patients required surgery, tissue will be analyzed for histopathologic correlate. The data gathered will not be considered definitive, but rather will be used to as preliminary data in support of a larger, definitive study.

Inclusion Criteria: Age ≥ 18 years Patient is able to provide written informed consent prior to study registration Histologically-confirmed high-grade glioma Completion of treatment with standard radiation (with or without concurrent therapy). Standard gadolinium-enhanced MRI changes that are considered indeterminate for tumor progression vs. treatment-related changes by the neuroradiologist or clinician within 24 weeks of completion of radiation. Exclusion Criteria: Inability to undergo or cooperate with an MRI or PET scan (e.g., claustrophobia, metal implant) Renal insufficiency with recent (<3 month old) creatinine > 2.0 mg/dL Pregnant or nursing female