Diffusion Weighted Magnetic Resonance in Imaging Younger Patients With Newly Diagnosed Bone or Soft Tissue Sarcomas

Children with sarcomas are routinely assessed with a variety of imaging techniques that involve the use of ionizing radiation. These include computed tomography (CT), nuclear bone scan, and positron emission tomography-CT (PET-CT). Pediatric sarcoma patients undergo many imaging studies at the time of diagnosis, during therapy and for years following completion of therapy. Because children are in a stage of rapid growth, their tissues and organs are more susceptible to the harmful effects of ionizing radiation than are adults. Furthermore, compared to adults, children have a longer life expectancy and, therefore, a longer period of time in which to develop the adverse sequelae of radiation exposure, such as the development of second malignancies. Alternative experimental methods of measuring tumor response will be compared to current standard of care measures to determine if the experimental method is equivalent to methods currently being used. Investigators wish to determine if they can reduce patient's exposure to the harmful effects of ionizing radiation by replacing imaging studies that use radiation with whole body diffusion weighted magnetic resonance imaging (DW-MRI) which does not use any radiation. They also want to know if DW-MRI measurements of the tumor can tell how well the tumor is responding to therapy. There have been studies in adults with cancer that have shown that DW-MRI provides useful information about how tumors are responding to therapy. There have only been very small studies of DW-MRI in children with tumors in the body. Therefore, the role of DW-MRI in pediatric sarcoma patients is not yet known and it is still experimental. This study might give us important information that could help us treat other children with bone or soft tissue sarcomas in the future.

Sex

All

Inclusion Criteria:

* All St Jude patients with a known or suspected, newly diagnosed bone or soft-tissue sarcoma who will be treated on or as per disease specific protocols.
* Study subjects will have undergone or are scheduled for PET-CT and/or bone scan within about 2 weeks of the WB and primary tumor DWI MRI.
* No limit on age or gender
* Informed consent or assent signed by study subject or parent/guardian according to institutional guidelines.
* Patients should not have begun therapy, or, needed research imaging can be performed within 2-5 days of starting therapy.

Exclusion Criteria:

* Subject has a tumor that will undergo upfront resection
* Subject is unable or unwilling to follow study requirements, including signed consent or assent
* Subject is hospitalized in the intensive care unit.
* Subject does not meet institutional MRI safety screening requirements.
* Subject has undergone primary tumor resection prior to arrival at St. Jude.
* Subjects who require sedation for WB MRI will be excluded if they have:

  * An acute cardiopulmonary process including, but not limited to, croup, reactive airways disease, pneumonia, clinical or radiological evidence of pericardial effusion or other cardiopulmonary disease.
  * Vomiting within 24 hours of the MRI or substantial nausea that may preclude sedation as determined by the anesthesiologist or certified registered nurse anesthetist.