Five-time Olympic gold medalist Nathan Adrian has revealed he's undergoing treatment for testicular cancer. But despite the diagnosis, the swimming star plans to continue training for the 2020 Summer Games in Tokyo.

Adrian, 30, has been a fixture on the U.S. National Team for more than a decade. He won an individual gold in the 100-meter freestyle in London at the 2012 Games and has been part of gold-medal relay teams in each of the past three Olympics.

Adrian made his condition public Thursday in an optimistic Instagram post: "On the bright side, we caught it early. I have already started treatment and the prognosis is good," he wrote.

Adrian said he made his condition public "to help break the stigma of discussing men's health issues."

He plans to be back in the water in a few weeks, "with my sights fully set on Tokyo!"

Adrian had qualified for the 2019 Pan American Games roster, but it's unclear whether he'll compete.

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