For the past 40 years, radiation has been the most effective method for treating deadly brain tumors called glioblastomas. Unfortunately, beams of radiation still must pass through healthy brain tissue to reach the tumor, and patients can only tolerate small amounts before developing serious side effects. A group of researchers at The University of Texas Health Science Center at San Antonio have developed a way to deliver nanoparticle radiation directly to the brain tumor and keep it there. The method doses the tumor itself with much higher levels of radiation -- 20 to 30 times the current dose of radiation therapy to patients -- but spares a much greater area of brain tissue. The study, published today in the journal Neuro-Oncology, has been successful enough in laboratory experiments and animal models that they're preparing to start a clinical trial, said Andrew Brenner, the study's corresponding author and a neuro-oncologist at the CTRC who will lead the clinical trial.