Using Positron Emission Tomography to Predict Intracranial Tumor Growth in Neurofibromatosis Type II Patients
Condition: Neoplasms; Nervous System Disease; Vestibular Disease
MeSH terms: Neurofibromatoses; Neurofibromatosis 1; Neurofibroma; Neurofibromatosis 2; Vestibular Diseases; Nervous System Diseases
Study type: Observational

Summary: 
      Background:

        -  Neurofibromatosis type II (NF2) is associated with tumors of the nerves, brain, and
           spinal cord. Most people with NF2 develop vestibular schwannomas, or tumors on the
           hearing and balance nerves. As they grow, vestibular schwannomas can cause hearing loss
           and balance problems. If they grow very large they can cause more serious problems, such
           as seizures, loss of eyesight, weakness, speech problems, and problems with the sense of
           touch. More research is needed into NF2 because researchers do not completely understand
           why these tumors occur or what makes them grow over time.

        -  Currently, tumor size is measured with magnetic resonance imaging (MRI) scans. However,
           MRI scans cannot predict how fast a tumor will grow. By using positron emission
           tomography (PET) scanning, researchers hope to be able to predict sudden growth spurts
           of tumors associated with NF2 and develop better treatment methods for this type of
           cancer.

      Objectives:

      - To use magnetic resonance imaging and positron emission tomography to better understand the
      growth of brain tumors in people with neurofibromatosis type II.

      Eligibility:

      - Individuals between 18 and 50 years of age who have been diagnosed with NF2 and have at
      least three untreated intracranial tumors.

      Design:

        -  This study requires an initial set of outpatient visits to the NIH Clinical Center that
           will last 7 to 10 days.

        -  Participants will have a physical and neurological examination and blood tests at the
           first visit. Participants will then have the following imaging studies to examine the
           tumors:

        -  MRI scans of the brain

        -  PET scans of the brain, combined with a computed tomography (CT) scan. The PET scans
           will be performed on separate days. Different contrast agents will be used for both
           scans, so researchers will inform participants if they need to fast or follow other
           procedures before having the scan.

        -  After the initial imaging studies, participants will have additional MRI scans every 6
           months for 2 years to track tumor growth.
    

Detailed description: 
      OBJECTIVE:

      The objective of this prospective observational study of intracranial tumors in patients with
      neurofibromatosis type 2 (NF2) is to gain insight into the use of 18F-fluoro-deoxyglucose
      (FDG) and 3 -deoxy-3 -18F-fluorothymidine (FLT) positron emission tomography (PET)/computed
      tomography (CT) as a predictive measure of future tumor growth patterns.

      STUDY POPULATION: <TAB>

      Twelve patients, ages 18-50, with a clinical or genetic diagnosis of NF2 and harboring at
      least 3 unoperated intracranial tumors (meningiomas and/or vestibular schwannomas) will
      participate in this study.

      DESIGN:

      Study participants will be evaluated with a thorough physical and neurologic examination upon
      enrollment. This initial outpatient evaluation will include contrast-enhanced magnetic
      resonance imaging (MRI) of the brain, FDG-PET/CT and FLT-PET/CT scans.

      Subjects will be followed as outpatients for two years, during which time MRI evaluation will
      be performed every six months.

      OUTCOME MEASURES:

      Based on data derived from this study, we hope to correlate FDG-PET/CT and FLT-PET/CT scans
      with metabolic activity and cellular proliferation within tumors. These findings will help us
      better forecast tumor growth and senescence. These findings should permit the safer treatment
      of the subset of tumors that will grow and cause symptoms and avoid the unnecessary treatment
      of lesions that will remain stable (not requiring treatment) in these patients.
    

Time perspective: Prospective
Keywords: PET Imaging; Vestibular Schwannoma; Neurofibromatosis; Neurofibromatosis Type 2; NF2