(NEXSTAR) – “Seinfeld” actor Michael Richards has revealed that he underwent surgery to remove his prostate after being diagnosed with stage 1 prostate cancer in 2018, the actor told People in an exclusive interview.

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

Richards added that his son, who was 9 at the time, was on his mind when he ultimately decided to fight his cancer, rather than come to terms with his death.

Patients have a higher chance of receiving successful treatment and remaining disease-free the earlier prostate cancer is detected, according to Johns Hopkins Medicine. With a 5-year relative survival rate of nearly 100%, prostate cancer has among the best overall prognosis of all cancers, experts note.

The 74-year-old actor reportedly writes about his cancer battle in his soon-to-be-released memoir, “Entrances and Exits,” available June 4.

Richards, probably best known for playing Cosmo Kramer on NBC’s hit series “Seinfeld,” has stayed out of the spotlight in recent years, only recently making a rare red-carpet appearance at the premiere of Jerry Seinfeld’s Netflix film “Unfrosted.” Prior to that, his last red-carpet appearance was in 2015, Entertainment Weekly reported.

In addition to his battle with cancer, Richards’ memoir is expected to cover the viral 2006 incident that prompted him to step back from Hollywood — when he made racist remarks during a stand-up performance at the Laugh Factory.

Richards told People he was “immediately sorry” the moment he uttered the slur, though he said he’s not intending to be forgiven, or make a “comeback.”

“It was time to disappear and finally pay attention to where all of my anger was coming from,” Richards told People of his intentions after disappearing from show business. “The most I could do for everybody was go home and get my s— together.”

Richards, in his upcoming memoir, says his book is “a hymn to the irrational, the senseless spirit that breaks the whole into pieces, a reflection on the seemingly absurd difficulties that intrude upon us all.”

The book’s publishers further said the memoir will give readers a peek into the “extraordinary life of a comedy genius,” as well as the journey Richards “has traveled in search of understanding.”

Addy Bink contributed to this report.