“We have always been very vocal about the importance of family and the love we have for our children. Luisana and I have put our careers on hold in order to devote all our time and attention to helping Noah get well.
“At this difficult time, we ask only for your prayers and respect for our privacy. We have a long journey in front of us and hope that with the support of family, friends and fans around the world, we will win this battle, God willing.”
They couple are yet to confirm the type of cancer, but it is believed the diagnosis was made after a recent trip to the US over health concerns.
The 41-year-old star recently made an appearance on ITV's Loose Women, where he praised his children for giving him perspective and opened up about fatherhood.
"The only regret that I have in my life is that I took this long to have kids, because I had no idea the perspective it would give me.
"I had no idea how much I would love being a dad. That's it, that's all I care about... I love them too much probably, if there was such a thing.
"It's made everything else so insignificant, moments that I was afraid of and moments that would overwhelm me have now become a joy because I've realised how not serious they are compared to what is really important, which is Noah and Eli and that's it."
The couple are also parents to nine-month-old son Elijah.