United States Senator John McCain of Arizona has been diagnosed with a common form of cancer called glioblastoma after a tumor was discovered in his brain.
The former Republican presidential hopeful's office released a statement Wednesday evening from the Mayo Clinic regarding the diagnosis.
"On Friday, July 14, Sen. John McCain underwent a procedure to remove a blood clot from above his left eye at Mayo Clinic Hospital in Phoenix. Subsequent tissue pathology revealed that a primary brain tumor known as a glioblastoma was associated with the blood clot," stated the Mayo Clinic.
"The Senator and his family are reviewing further treatment options with his Mayo Clinic care team. Treatment options may include a combination of chemotherapy and radiation."
Here are five facts about glioblastoma, including life expectancy, if it can be cured, and how McCain is not the first prominent U.S. senator to suffer from it.
Life expectancy for those diagnosed with glioblastoma can range from 14 months to five or more years, according to the American Brain Tumor Association.
"The ABTA labels the prognosis for glioblastoma survival in terms of median survival — the length of time at which an equal number of patients do better and an equal number of patients do worse," reported CNN.
"Depending on the type of glioblastoma and treatment used, this can range from 14 months to three years. The association also cites a 2009 study that found 10% of patients with glioblastoma may live five years or longer. The average survival time for malignant glioblastoma is around 14 months with treatment ..."
Glioblastoma is considered by experts to be the most aggressive form of brain cancer among adults, meaning that it can rapidly grow within the brain.
"Glioblastoma tumors make their own blood supply, which helps them grow. It's easy for them to invade normal brain tissue," noted WebMD.
"Glioblastoma is a type of astrocytoma, a cancer that forms from star-shaped cells in the brain called astrocytes. In adults, this cancer usually starts in the cerebrum, the largest part of your brain."
According to the experts, at present there is no cure for glioblastoma. There are, however multiple treatments to slow or ease symptoms.
Cancer Treatment Centers of America noted that the main ways for treating glioblastoma included surgery, chemotherapy, radiation therapy, and the newer targeted therapy.
"Targeted therapy [involves] medicines that target the parts of cancer cells that make them unlike normal cells. These new drugs are used more often to treat brain tumors than standard chemotherapy," explained CTCA.
"Targeted therapy can help when other treatments are not working as well. They can also have less-severe side effects than standard chemotherapy medicine."
During the much-watched Senate hearing over former FBI Director James Comey last month, many noted that McCain's line of questioning was a confusing one.
"He referred to 'President Comey,' and at times looked confused and frustrated with Comey's answers," reported The Washington Post in June.
"Viewers clearly thought it was notable; Twitter announced it was the most-tweeted moment of the hearing."
Given that, in addition to seizures and headaches, symptoms of glioblastoma include confusion and memory loss, some are now speculating that the bizarre line of questioning may have been an indicator of his recent diagnosis.
McCain is not the first prominent member of the United States Senate to be diagnosed with glioblastoma.
In 2009, Senator Edward "Ted" Kennedy of Massachusetts succumbed to the cancer, being diagnosed with the disease in May 2008 following a seizure.
"[In June 2008], he underwent what was described as 'successful' surgery at Duke University Medical Center, Durham, North Carolina, and then received both chemotherapy and radiation after returning home to Massachusetts," noted Medscape Oncology in an August 2009 article.
"Six months after the diagnosis, Senator Kennedy had returned to the Capitol ... However, in January 2009, he collapsed during the inaugural luncheon for the new president Barack Obama and appeared to be having a seizure as he was helped from the room by medical personnel."
Medscape added that the timeline for Kennedy's diagnosis and death was typical for cases involving glioblastoma.