Seinfeld star Michael Richards has revealed he secretly battled prostate cancer six years ago.

The 74-year-old actor – who has daughter Sophia from his previous marriage to Cathleen Lyons and a young son with his wife Beth Skipp – initially believed he was “ready to go” when he received the shock diagnosis in 2018.

But he has has since admitted his family was a catalyst for him electing instead to have life-saving surgery.

“I thought. well, this is my time. I’m ready to go. But then my son came to mind just a few seconds later and I heard myself saying, ‘I’ve got a nine-year-old and I’d like to be around for him. Is there any way I can get a little more life going?’,” Richards told People magazine.

“It had to be contained quickly. I had to go for the full surgery. If I hadn’t, I probably would have been dead in about eight months.”

The star has been mostly out of the spotlight since the years when he was known globally for his role as Cosmo Kramer on the classic sitcom Seinfeld. He decided to tell his story in a memoir titled Entrances and Exits because he wanted to be able to “connect” with his memory and do a “full review” of his life – as he joked he was “surprised at how much he actually remembered” in the writing process.

“I had over 40 journals I’d kept over the years and wanted to do a full review of my life. I’m turning 75, so maybe wanting to do that is something that comes with being my age,” Richards said.

“I wanted to connect with feelings and memory. I’m surprised at how much I was able to remember.”

Entrances and Exits will be published in June.