Nick Cannon Shares Why He and Alyssa Scott Didn't Want Son to Undergo Chemotherapy Before Death

Bruce Glikas/WireImage; Nick Cannon

Nick Cannon is opening up about the months he and Alyssa Scott spent between learning of son Zen's cancer diagnosis and his death.

In an episode of Paramount+'s The Checkup with Dr. David Agus, the Masked Singer host, 42, opened up about how they came to learn that their infant son had brain cancer.

"He was healthy, active, always smiling," Cannon said of his baby boy's early days, until around two months old, he noticed the infant's "interesting" breathing patterns.

"Being a father of multiple kids, it's always the biggest guilt on me is that I don't get to spend enough time with all my children, one 'cause I'm constantly working and two because I'm just spread thin."

"We [also] noticed his head was a little larger, [but] all my kids have big heads. I was a big-headed baby," Cannon added.

Suspecting Zen might have asthma, the parents took him to a doctor's appointment where his physician was immediately concerned with the size of the baby's head, which was the "first sign something was occurring."

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RELATED: Nick Cannon Says He Will 'Never Get Over' Losing Son Zen on 'Painful' Anniversary of His Death

"They did a lot of tests. They didn't let him leave the hospital," he recalled. "And so you could imagine you think you're taking your son in to get a checkup for — at the worst, I was thinking asthma, you know? And to know that he gets diagnosed with brain cancer, that was a shock."

He asked doctors to "be upfront" with him so that he could prepare himself and protect Scott from what might happen next, noting doctors "kind of laid it out for me."

Zen was diagnosed with high-grade glioma, a rare and aggressive form of brain cancer. Cannon and Scott were presented with the option of chemotherapy as a course of treatment.

"When we first went to the hospital, just to decrease his head from rapidly continuing to grow, there were a couple of procedures we were all for," he said, explaining they used a shunt to drain fluid from Zen's brain.

"That, to me, made logical sense. There was less pain on him and the procedure was quick. It was all about quality of life," he noted.

Alyssa Scott/Instagram

"From that point, they pretty much told me that best case scenario, your son could live to 3 or 4 years old. So instantly when I heard that, I thought quality of life. I wanted him to have the best existence he could have."

When it came to chemo, Cannon asked if that would extend Zen's life or lessen his suffering, to which they told him, "not really," because of the placement of the tumor.

"Seeing your son hooked up to all of those machines — and he had to go for a shunt two or three times, and that was heartbreaking every time — even in that short amount of time, I couldn't imagine him having to go through chemo."

Cannon experienced a form of chemo himself as treatment for his lupus and "knew what that did to me."

Alyssa Scott Instagram

"I knew how as a full grown man, that process ... My hair was falling out," he said. "I wouldn't even call it pain; it just sucked everything out of you. I couldn't imagine that on a newborn and what that would do."

In their concerns for Zen's quality of life, the treatment option would have also required him to "live in the hospital."

"He would have never gone home," Cannon said, explaining he and Scott ultimately "went to the space of 'we want to enjoy him and we want him to enjoy [us].'"

The last days were "tough" for the father, who credited Scott for "her strength, her resilience."

"I definitely couldn't have did it without her. The fact that she was the one, from every aspect she handled it," he acknowledged. "We had some beautiful moments. We had the opportunity, we knew the transition was coming. It happened a lot faster than we thought, but even that last weekend I knew, 'this is probably going to be the last weekend.'"

Cannon continued, "Luckily we did everything from the sunrise, going to the beach, the sunset, said some beautiful prayers as a family, and really came together as a family in a very beautiful way. I'm grateful for that, but it was definitely tough. To see your child there, suffering at a point and watching things shut down, it was pretty intense."

In addition to Zen and his second baby on the way with Scott, Cannon also shares sons Rise Messiah, 10 weeks, and Golden Sagon, 5, as well as daughter Powerful Queen, 23 months, with model Brittany Bell.

He is also dad to daughter Beautiful Zeppelin, 3 weeks, and twins Zion and Zillion, 17 months, with Abby De La Rosa, as well as 11-year-old twins Monroe and Moroccan with ex-wife Mariah Carey. He also shares son Legendary Love, 5 months, with model Bre Tiesi and welcomed daughter Onyx Ice Cole with former Price Is Right model LaNisha Cole in September