Assessment of Treatment Response of Nasopharyngeal Cancer Using Simultaneous 18F-FDG-PET and MRI
Condition: Nasopharyngeal Cancer
MeSH terms: Nasopharyngeal Neoplasms; Nasopharyngeal Carcinoma
Study type: Observational

Summary: 
      The overarching goal of this study is to develop PET/MR techniques for accurate assessment of
      treatment response during and immediately after chemoradiation therapy. The central
      hypothesis is that the GMR measured using a simultaneous PET/MR scanner can more accurately
      detect residual tumor than conventional SUV measures from PET alone. It is important to note
      that SUV depends on both tumor metabolic rate and tracer delivery, which makes the
      interpretation of SUV challenging. For instance, inflammatory tissue can have high SUV due to
      increased vascularity and vascular permeability and cannot be easily differentiated from
      tumor based on the SUV. Investigators hypothesize that inflammatory tissue will have lower
      GMR than residual tumor that contain highly proliferating cells with increased expression of
      glucose transporters (GLUT). Measuring GMR accurately will improve the specificity of PET
      while maintaining the high sensitivity of PET for detection of residual tumor. In order to
      test our hypothesis, investigators propose to conduct dynamic PET and MRI scans with NPC
      patients who are undergoing a conventional two-stage chemoradiation therapy at our
      institution; the first stage for 7-week chemoradiation therapy followed by the second stage
      for 3-month chemotherapy. A combination of PET/CT and nasopharynx MRI is currently obtained
      before the initiation of treatment and 3 months after completion of treatment to assess
      treatment response.

      This study proposes to introduce PET/MR scans at the time of these exams (scan #1 for
      pre-treatment & scan #4 for 3 months after completion) and to add two additional PET/MR scans
      in between them; one immediately after the first stage of treatment (scan #2) and another one
      immediately after the second stage (scan #3). A primary clinical endpoint of this study is
      the treatment response assessed at 3 months after completion of treatment. A secondary
      endpoint is 6 month follow-up exam. Complete responder will be determined based on clinical
      and imaging assessment of residual tumor size at each endpoint.

      It is hoped that preliminary data obtained from this study will be useful in planning larger
      studies to formally investigate the utility of GMR for detection of residual tumor and
      prediction of treatment response.
    


Intervention name(s): PET/CT scans
Intervention type(s): Diagnostic Test
Intervention description(s): (approximately 18 mSv/scan) and perform maximum two additional PET/MR scans; one immediately after the first stage of treatment and another one immediately after the second stage if the 3-month chemotherapy is given).
Observational model: Case-Only
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Patients (n=20) with nasopharyngeal cancer who are scheduled for chemoradiation therapy are
        eligible.