From the Duke News Service

March 28, 2001

Dr. Darell Bigner of the Duke University Medical Center has received a $1.25 million grant from the Pediatric Brain Tumor Foundation of the U.S. to build on current research and improve treatment of childhood brain tumors.

The five-year grant, largest awarded by the foundation, will help Bigner and his colleagues at the Brain Tumor Center at Duke move targeted treatment into studies in patients with medulloblastoma, the most common brain tumor in children under 9.

Currently, medulloblastoma is treated with surgery to remove the tumor and then external beam radiation to prevent the cancer from returning in the brain or spinal cord. This approach gives a survival rate at five years of 40 percent to 80 percent. However, external beam radiation causes severe long-term effects in the youngest patients and it can only be used once per patient because of the potential for damage to normal brain and spinal tissues.

"A new treatment for medulloblastoma and its complications would represent a significant clinical advance," said Bigner, the deputy director of Duke Comprehensive Cancer Center and the Edwin L. Jones, Jr., and Lucille Finch Jones Cancer Research Professor.

Bigner and his colleagues hope to deliver radiation therapy directly to cancerous cells instead of exposing the entire brain and spinal cord to radiation. Targeting radiation to cancer cells should reduce the potential side effects and perhaps allow the treatment to be used repeatedly in the same patient, Bigner said.

Recently the researchers, led by Carol Wikstrand and Dr. Gregory Riggins, identified a protein that is found in more than 89 percent of medulloblastomas, and they will continue to look for other proteins found only on medulloblastoma cells under the grant from the Pediatric Brain Tumor Foundation of the U.S.

By creating antibodies that recognize these medulloblastoma-specific markers, or antigens, and then attaching a radioactive atom to the antibody, the scientists will have a vehicle that can deliver radiation just to the medulloblastoma cells.

In addition, they can reduce damage to normal tissues even further by choosing the right radioactive atom. Right now, they expect to use either astatine-211 or iodine-131, both of which destroy cells only in the immediate vicinity.

"We want to find the best antigen to target, then develop the best antibody against that antigen, and choose the best radioactive atom so we can minimize damage to normal brain and spinal tissues," Bigner said. "External beam radiotherapy will remain an important part of treatment for medulloblastoma and other cancers, but this approach may eventually improve treatment of medulloblastoma."

The American Cancer Society estimates that about 550 children will be diagnosed with medulloblastoma each year in the United States, about 2,200 will be diagnosed with brain and spinal cord tumors including medulloblastoma, and about 12,400 children under age 20 will be diagnosed with some kind of cancer, including brain cancers. Tumors of the brain and spinal cord are the second most common cancer in children after leukemia.

The Brain Tumor Center at Duke http://cancer.duke.edu/btc was founded in 1937. The Pediatric Brain Tumor Foundation of the U.S. http://www.pbtfus.org, based in Asheville, supports medical research and increases public awareness of pediatric brain tumors.

[back to main news page]