Michael Buble has called his son Noah his hero after the youngster bravely beat liver cancer.

During a Carpool Karaoke special with comedian James Corden for Stand Up To Cancer U.K., an emotional Buble struggled to talk about his son's battle with the disease, and cried as he said his "life ended" when Noah, then three, was hospitalised in 2016.

“It’s so hard to have to acknowledge it because it’s so painful to talk about,” the Cry Me a River hitmaker, 43, explained. “We got the diagnosis and that was it, man, my whole life ended.”

Describing the strength his son had while undergoing surgery and seven months of chemotherapy, he sweetly revealed he told Noah he was a real-life superhero.

“It’s funny, I know he’s five years old and I say to him – cause he loves Spider-Man, we love Spider-Man – and I always say to him, ‘Spider-Man’s amazing, Superman’s amazing, but they’re fake; they’re not real. You’re a superhero, you’re my hero, my real superhero," he gushed.

Both Buble and Corden wept as the Canadian singer recalled the harrowing time for him and wife Luisana Lopilato, and thanked the model, 31, for being a pillar of strength after Noah, then three, got the all-clear from cancer.

“When this all started, I became the strength to somehow pull us and lift us and to be positive,” the Grammy award-winning singer said. “When they got (the cancer) out and the chemo was done and they said, ‘We did it, it’s good, he’s okay,’ I fell, I just fell. My wife picks me up now.”

After his Carpool Karaoke special aired during Stand Up To Cancer, TV Channel 4 was forced to delete a post on social media after they incorrectly claimed Noah had died.

"Watching Michael Buble talking about the death of his son from Cancer is one of the most heartbreaking things we've ever watched. Sending him and his family so much love for telling their story!" the channel's official page shared on Twitter, leading outraged fans to point out the mistake.