US Senator John McCain, the Republican nominee in the 2008 presidential election, was on Wednesday diagnosed with an aggressive form of brain cancer. The 80-year-old has had non-invasive melanomas removed at least three times. 

On Friday, July 14, 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 tumour known as a glioblastoma was associated with the blood clot.

Scanning done since the procedure (a minimally invasive craniotomy with an eyebrow incision) shows that the tissue of concern was completely resected by imaging criteria.

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. McCain's doctors say he is recovering from his surgery 'amazingly well' and his underlying health is excellent.

"Senator McCain appreciates the outpouring of support he has received over the last few days. He is in good spirits as he continues to recover at home with his family in Arizona," McCain's office said a statement.

"He is grateful to the doctors and staff at Mayo Clinic for their outstanding care, and is confident that any future treatment will be effective. Further consultations with Senator McCain's Mayo Clinic care team will indicate when he will return to the United States Senate," the statement added. 

John McCain
US senator John McCainReuters

McCain had retired from the US Navy as a captain in 1981 and moved to Arizona, where he entered politics. Elected to the US House of Representatives in 1982, McCain served two terms. He was first elected to the US Senate in 1986, winning re-election easily five times, most recently in 2016.

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