An experimental form of radiation therapy could more effectively target lethal cancers.
Scientists from the Idaho National Engineering and Environmental Laboratory, collaborating with scientists from Argentina, developed Boron Neutron Capture Therapy (BNCT) to battle malignant brain tumors. Currently, surgeons cannot remove all cancerous tissue in the brain. Also, these tumors resist standard radiation treatment and chemotherapy.
The method involves delivering concentrated doses of radiation directly to tumors while sparing healthy tissue. The malignant tissue is targeted with a carrier of elemental boron-10 and then exposed to a beam of neutrons. "A neutron colliding with a boron atom produces an alpha particle and a lithium ion," says David Nigg, an INEEL physicist. "These highly energetic charged particles won't travel farther than the width of a cell, ideally leading to selective destruction of the tumor and sparing the neighboring normal tissue," he says.
According to researchers, treatment success depends on loading just the tumor cells with boron. Scientists attach boron-10 to a "delivery agent" that has an affinity for tumor cells. Before treatment, patients ingest the agent either orally or intravenously, and boron accumulates in the tumor. The FDA has approved only three boron delivery agents for human use. Calculating the dose of radiation is critical, says INEEL scientists. Special software that calculates the doses, called Simulation Environment for Radiotherapy Applications or Sera, is currently being used in clinical trials in Finland and Sweden.