U.S. Olympic swimmer Nathan Adrian announced Thursday on Instagram that he has testicular cancer, but said doctors caught the disease in its early stages and “the prognosis is good.”

“I will be back in the water in a few short weeks with my sights fully set” on next year’s Tokyo Olympics, he wrote in the caption that accompanied the photo, which shows him next to his wife, Hallie.

Adrian, 30, has won five gold medals over the past three Olympics (only six U.S. swimmers — male or female — have more). As a 19-year-old in 2008, he helped the U.S. 400-meter freestyle relay team win gold by swimming the first leg in a preliminary heat. Four years later in London, he won the individual 100 freestyle competition and swam the freestyle leg of the gold medal-winning 400 medley relay team, and at Rio 2016, Adrian added gold on both 400 relay teams. He also has one silver and two bronze medals.

Last month, Adrian was named to the U.S. swimming roster for this year’s Pan American Games, which begin in July in Lima, Peru, though it’s unclear whether he still will compete. He was scheduled to swim in the 50 and 100 freestyle events.

USA Swimming sent its regards to Adrian via Twitter:

As did the “Today” show’s Carson Daly, whose father died of cancer and mother also had the disease.

Adrian wrote that he hopes his fight with cancer raises awareness of the disease.

“I’ve realized that too often we tend to avoid these important topics, ignore the potential warning signs and put off getting the medical help that we may need,” he said. “As I told my family, I’ll be putting my public health degree to work a little sooner than I planned!”

The Mayo Clinic describes testicular cancer as “rare” and “highly treatable” but adds that it’s the most common form of cancer for U.S. men between the ages of 15 and 35.

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