James Michael Tyler, the actor who played Gunther on “Friends”, opened up about his struggle with prostate cancer on “Today” Monday.

The star, who was diagnosed with the illness in September 2018, told Craig Melvin that it had not been caught early and had advanced to other parts of his body.

“I was diagnosed with advanced prostate cancer, which had spread to my bones,” Tyler explained. “I’ve been dealing with that diagnosis for almost the past three years. It’s stage 4 (now). Late-stage cancer. So eventually, you know, it’s gonna probably get me.”

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The actor said that the illness was discovered during an annual checkup.

“I was 56 years old at the time, and they screen for PSA, which is prostate-specific antigen,” Tyler shared. “That came back at an extraordinarily high number… So I knew immediately when I went online and I saw the results of my blood test and blood work that there was obviously something quite wrong there. Nearly immediately, my doctor called me and said ‘Hey, I need you to come in tomorrow because I suspect that you may have quite a serious problem with your prostate.'”

After additional testing, Tyler received the devastating diagnosis. He was referred to Dr. Matthew Rettig, a research scientist and oncologist at UCLA, who was able to use genetic testing to help him determine that the illness was genetic, not environmental.

Tyler explained how he embarked on hormone therapy, which he said “worked amazingly for about a year,” allowing him to “go about life regularly” while taking a regimen of three drugs.

“All I had to do was take a pill in the morning and the night, and boom, life was pretty much normal,” Tyler went on.

Tyler said that the cancer, which eventually spread to his bones and spine, leading to paraplegia, or paralysis of the lower body, mutated “right at the time of the pandemic.

“I missed going in for a test, which was not a good thing,” the beloved star told the host. “So the cancer decided to mutate at the time of the pandemic, and so it’s progressed.”

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He’s currently undergoing chemotherapy, which is “aggressively” fighting the cancer. However, he wanted to emphasize that screening and early diagnosis can lead to far better prognoses: “There are other options available to men if they catch it before me.

“Next time you go in for just a basic exam or your yearly checkup, please ask your doctor for a PSA test. It’s easily detectable. If it spreads beyond the prostate to the bones, which is most prevalent in my form, it can be a lot more difficult to deal with.”

“A lot of men, if they catch this early, it’s easily treatable,” Tyler urged. “I don’t want people to have to go through what I’ve been going through. This is not… an easy process.”

Tyler shared how his cancer battle was the reason he appeared on Zoom rather than in person for the “Friends” reunion show, which aired last month.

“I wanted to be a part of that, and initially I was going to be on the stage, at least, with them, and be able to take part in all the festivities,” Tyler said.

“It was bittersweet, honestly. I was very happy to be included. It was my decision not to be a part of that physically and make an appearance on Zoom, basically, because I didn’t wanna bring a downer on it, you know? I didn’t want to be like, ‘Oh, and by the way, Gunther has cancer.'”

Tyler’s goal is to encourage people to get screened, hoping to “save just one life” with his important message.

“That’s my only reason for coming out like this and letting people know,” Tyler explained. “That’s my new role.”

He shared, “It’s made me, personally, just realize how important every moment is, every day.”

Adding, “And fighting. Don’t give up. Keep fighting. Keep yourself as light as possible. And have goals. Set goals. My goal this past year was to see my 59th birthday. I did that, May 28th. My goal now is to help save at least one life by coming out with this news.”

Tyler’s manager and friend, Toni Benson, told People the star had been going “through some rough times” but insisted, “he wants to live.”

“He’s going to fight this,” she said. “Lately he’s been having amazing days. He’s done his second round of chemo and so far he is doing really well. And he’s hopeful it will be effective.”

“Though he’s wheelchair bound, he’s very mobile,” Benson added. “He has the most amazing attitude. I don’t think he’s going anywhere for a long time.”