The deadly brain tumor glioblastoma multiforme often strikes without warning. It’s also the fastest growing tumor originating in the brain, and can vary greatly between patients. That makes it difficult to track or predict, which in turn presents a major obstacle to treatment. Now a new look at the condition has found a surprisingly accurate model for finding patterns in the tumor’s growth and determining the efficacy of treatment: weather patterns. Researchers say GBM growth can be tracked in the same way storms are tracked, using similar computer models.
“Glioblastoma” means the tumor grows from the glial cells that protect, insulate, secure, and nourish the neurons in the brain. “Multiforme” refers to the fact that it presents in a variety of diverse forms. It is found more frequently in men then in women, and like many cancers it is more common in patients over 50. Although no sign of a general hereditary predisposition to GBM has been found, several genetic disorders, including neurofibromatosis, carry an increased risk of the condition. Certain kinds of chemical exposure seem to make the tumor more likely; some studies indicate a connection to PVC. Lead exposure also seems to be linked with the condition.
One study suggests that a phenomenon called genetic fusion may be connected to GBM. This is a type of mutation in which two genes that are unrelated but have segments that look similar link up with each other, like pieces of a jigsaw puzzle that match in shape but not color. When this happens, neither gene can be properly expressed, and the entire affected chromosome is disrupted. One particular merger has been linked with three percent of all GBM cases, and it is believed that others may be collectively responsible for a substantial portion.
The median survival rate of GBM is just 15 months after diagnosis, but that number is lengthening. In the past five years, the number of patients who survived more than two years tripled, thanks in part to improved treatments. Two common treatments are surgery and radiation therapy, but radiation carries the risk of itself causing further tumors, and surgery is dangerous. The storm forecasting model recently developed helps measure the effectiveness of these treatments. Since tumors, like storms, are chaotic systems but nonetheless follow known patterns, doctors can use similar mathematical models to predict how the tumor would have grown without intervention, and compare the results of the intervention to that prediction.