"Over the past 20 years, survival from medulloblastomas has dramatically improved," says pediatric neurologist Scott Pomeroy, first author of the paper. "In modern clinical trials, more than 80 percent of good-risk patients survive. Nearly 100 percent of the survivors, however, have learning disabilities, most have hearing loss and cataracts, and the majority are unable to live independent of their families as adults. A major goal of current treatment trials, then, is to reduce the level of radiation to lessen toxicity without compromising survival in good-risk patients."
Now, risk is defined by clinical criteria, such as the presence of metastases on MRI scanning, excessive tumor remaining in the brain after surgery, and examination of tumor tissue under a microscope. "Our predictor is much more accurate than these clinical criteria," says Pomeroy, also an associate professor at Harvard Medical School.
About 2,000 children a year are diagnosed with medulloblastoma, with diagnosis verified at the time of surgery. For this study, researchers examined gene expression patterns from 99 patient tumor samples of three different types of brain tumors. In addition to distinguishing tumor types from each other, the study found strong expression of a signaling protei
Contact: Bess Andrews
Harvard Medical School