|
|
|
|
|
|
||
|
|
||||
|
|
||||
|
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||
Clinical Investigations |
Department of Maxillofacial Surgery (V.-F.M., F.A.A.) and Laboratory for Tumor Biology and Developmental Disorders (L.K.), University Hospital Eppendorf, Hamburg, Germany; MRI Institute, Hamburg Othmarschen, Germany (F.A.A., C.F., R.W.); Pediatric Oncology Branch, National Cancer Institute, Bethesda, MD, USA (E.D., B.C.W.); Department of Medical Genetics, University of British Columbia, Vancouver, Canada (J.M.F.)
Address correspondence to J.M. Friedman, Medical Genetics Research Unit, Children's & Women's Hospital, Box 153, 4500 Oak St., Vancouver, BC, Canada V6H 3N1 (frid{at}interchange.ubc.ca).
People with neurofibromatosis 1 (NF1) have multiple benign neurofibromas and a 10% lifetime risk of developing malignant peripheral nerve sheath tumors (MPNSTs). Most MPNSTs develop from benign plexiform neurofibromas, so the burden of benign tumors may be a risk factor for developing MPNST. We studied 13 NF1 patients with MPNSTs and 26 age- and sex-matched controls (NF1 patients who did not have MPNSTs) with detailed clinical examinations and whole-body MRI to characterize their body burden of internal benign neurofibromas. Internal plexiform neurofibromas were identified in 22 (56%) of the 39 NF1 patients studied. All six of the NF1 patients with MPNSTs under 30 years of age had neurofibromas visualized on whole-body MRI, compared to only 3 of 11 matched NF1 controls under age 30 (p < 0.05). Both the median number of plexiform neurofibromas (p < 0.05) and the median neurofibroma volume (p < 0.01) on whole-body MRI were significantly greater among MPNST patients younger than 30 years of age than among controls. No significant differences in whole-body MRI findings were observed between NF1 patients with MPNSTs and controls who were 30 years of age or older. Whole-body MRI of NF1 patients allows assessment of the burden of internal neurofibromas, most of which are not apparent on physical examination. Whole-body imaging of young NF1 patients may allow those at highest risk for developing MPNST to be identified early in life. Close surveillance of these high-risk patients may permit earlier diagnosis and more effective treatment of MPNSTs that develop.
Key Words: malignant peripheral nerve sheath tumor • MRI • neurofibromas • neurofibromatosis 1
|
|
