Former NBA player Jason Collins opened up about his recent brain cancer diagnosis. The 47-year-old shared he has stage 4 glioblastoma, which he described as “one of the deadliest forms of brain cancer.” Collins made headlines over a decade ago for being the first openly gay player in a major U.S. sports league.

Jason Collins shared he has stage 4 brain cancer, aka glioblastoma

Collins previously revealed he was undergoing treatment for a brain tumor in a statement released in September. At the time, details weren’t disclosed in order to guarantee his privacy. Collins decided to open up about his experience with symptoms, diagnosis and where he currently stands with his cancer.

On Thursday, he revealed he has stage 4 glioblastoma, one of the most aggressive types of brain tumors. Collins says he started noticing symptoms in August, when he was unable to focus on tasks such as packing a suitcase. 

“I had been having weird symptoms like this for a week or two, but unless something is really wrong, I’m going to push through. I’m an athlete,” he wrote in an essay for ESPN.

Collins went for a CT scan, which revealed his diagnosis: “Imagine a monster with tentacles spreading across the underside of my brain the width of a baseball,” he wrote.

What is glioblastoma?

Glioblastoma multiforme is one of the most aggressive types of brain cancer. Treatment such as chemotherapy may slow the progression of the tumor, but does not cure it fully.

“If brain tumors were sharks, the glioblastoma multiforme, or GBM, would be the great white. More than any other brain cancer, GBM inspires fear because of its almost unstoppable aggression,” Dr. Jon Weingart wrote for John Hopkins Medicine. “In fact, just a generation ago, the diagnosis of GBM meant facing a prognosis of months, or even weeks — not years — to live.”

Current treatment for glioblastoma multiforme allows some patients to live two to four years longer, sometimes more. When Collins received his diagnosis, he was told the tumor was growing so quickly that he could die within weeks. He decided to undergo radiation and chemotherapy treatment at a clinic in Singapore.

“We aren’t going to sit back and let this cancer kill me without giving it a hell of a fight,” Collins said, per ESPN. “We’re going to try to hit it first, in ways it’s never been hit: with radiation and chemotherapy and immunotherapy that’s still being studied but offers the most promising frontier of cancer treatment for this type of cancer.”