Radiation therapy has always been the most used and most effective way to treat certain brain tumors which are called glioblastomas. Even though it was a reasonably effective method of treatment, it still required radiation to pass through healthy brain tissue as it made its way to the malignant tumor. Most patients are only able to tolerate a small amount of brain radiation before they develop serious side effects.
Glioblastomas are among the most aggressive malignant brain tumor. They are also the most common. Despite this, their incidence is only about 2 or 3 cases per every 100,000 people in both Europe andNorth America. Treatment has traditionally been restricted to chemotherapy and radiation therapy and treatment outcomes have been poor with the average life span following diagnosis being about fourteen months.
A group of scientists at theSan Antoniocampus of theUniversityofTexashave been experimenting with ways in which to deliver nanoparticle radiation targeted directly at the brain tumor which allows for between 20 to 30 times the standard dose of radiation currently given in treatment. This treatment protocol will spare a much larger portion of healthy brain tissue while delivering a much more efficient level of radiation directly to the tumor site.
The results from this laboratory work were recently published in an issue of Neuro-Oncology. It is hoped that a clinical trial will begin soon at the Cancer Therapy andResearchCenter which will be headed up by Andrew Brenner, M.D., Ph.D. who was the lead scientist in the research study.
During the study, the scientists were able to deliver significantly higher doses of radiation to their study animals which was able to completely eradicate most tumors.
The radiation that is delivered is in the form of an isotope named rhenium-186. This isotope has a very short half-life which is the amount of time a radioactive substance takes to decay by half. This isotope’s radiation only extends by a few millimeters. But the scientists recognized that simply inserting a radioactive isotope into a brain tumor would not be effective unless they were able to come up with a way to hold it in place and prevent the bloodstream from carrying it away into other parts of the body. The problem was solved when colleagues came up with the idea of encapsulating the rhenium into tiny molecules of fat called liposomes which are only about 100 naometers across. This unique technology allows scientists to load the…