What is going on with John McCain?
As announced by his office Wednesday night, Sen. John McCain (R-Ariz.) was diagnosed with a brain tumor following surgery to take out a blood clot above his left eye.
That brain tumor is called a glioblastoma — but what exactly is that? Here are the key facts you need to know.
What is a glioblastoma?
It’s a typically malignant brain tumor that arises within astrocytes, or the star-shaped cells that make up a type of supportive tissue in the brain, according to the American Brain Tumor Association.
Glioblastomas usually appear in the cerebral hemispheres of the brain but can show up elsewhere in the brain or the spinal cord.
Glioblastomas can be one of two types: primary (de novo) or secondary. Primary glioblastomas, which are more common, show up quickly and are aggressive. Secondary glioblastomas grow over a longer period of time, but are just as aggressive. They could grow from lower-grade tumors to higher-grade ones.
What causes it?
While the cause may not be officially known, there are associations that indicate potential risk factors.
“Glioblastoma are more common in males, persons older than 50, and people of Caucasian or Asian ethnicity,” according to a Q&A with Dr. John de Groot, a professor at the University of Texas MD Anderson Cancer Center. “There are a few very rare familial syndromes that are associated with brain tumors. One of the only known risk factors that we have for brain tumors is radiation exposure.”
What are the signs?
Symptoms can vary based on where the tumor is located, according to the Cancer Treatment Centers of America. They can include everything from persistent headaches, double or blurred vision, vomiting, memory loss and speech difficulty.
McCain was complaining about fatigue and felt tired the last few months, and also had experienced double vision, Dr. Sanjay Gupta told Anderson Cooper on CNN Wednesday night.
How do you treat it?
“The first step in treating glioblastoma is a procedure to make a diagnosis, relieve pressure on the brain, and safely remove as much tumor as possible through surgery,” according to the American Brain Tumor Association. “Because glioblastomas have finger-like tentacles, they are very difficult to completely remove.”
Treatment options include surgery, radiation therapy, chemotherapy and targeted therapy (aka medicines specifically targeting the areas of cancer cells that differentiate them from normal cells).
What is the prognosis?
First things first: There is no cure for glioblastomas.
That said, “there is good evidence that the more tumor that can be removed, the better the prognosis,” according to de Groot. “The radiation and chemotherapy are designed to target the infiltrative component of the glioblastoma and delay tumor progression.”
The median survival rate of more aggressive glioblastomas in adults — when treated with both brain cancer drug temozolamide and radiation therapy — is approximately 14.6 months, with a 30 percent two-year survival rate. One 2009 study found nearly 10 percent of glioblastoma patients could live five years or more.
How common is it?
Two to three in every 100,000 people in the United States and Europe are newly diagnosed with glioblastomas every year, per statistics from the National Brain Tumor Society. Of all primary brain tumors, 15.4 percent are glioblastomas. They represent just three percent of brain tumors in children.
Both the late Sen. Ted Kennedy as well as Beau Biden, the late son of former Vice President Joe Biden, had these types of brain tumors as well, according to Gupta.
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6 Things You Didn’t Know About Glioblastomas originally appeared on usnews.com
