Céline Dion’s husband René Angélil “comes first”, according to her friend Robin Leach.

The singer made the difficult decision to cancel her Asian tour and postpone the rest of her professional activities to care for her 72-year-old spouse as he battles cancer.

But Robin said he wasn’t surprised to learn of Céline’s decision because her family have always been her priority.

"They are each other's lives," Robin told People. "He and her family come first and she's always made that clear."

Céline and René live in Las Vegas with their children René Charles, 13, and three-year-old twins Eddy and Nelson.

And as soon as René was diagnosed with the disease and underwent surgery to remove a throat tumour in December, Céline began to seriously consider a hiatus from show business to care for her partner.

"Last time I saw him, he was very thin and frail," Robin added. "Céline had to take a step back, and her decision is a realisation that you have to hold onto everything while you've got it."

However, Céline is also said to believe a positive attitude is important in René’s recovery process.

“They’re trying to stay positive," a source said. "They're optimistic. "

Celine has abandoned dates of her Asia stint, meant to start on November 11 in Nagoya, Japan. She was scheduled to start a Las Vegas residency on Friday at the city's Caesars Palace, but she has postponed that also.

"I want to devote every ounce of my strength and energy to my husband's healing, and to do so, it's important for me to dedicate this time to him and to our children," she explained. "I also want to apologise to all my fans everywhere, for inconveniencing them, and I thank them so much for their love and support."

This is René's second battle with cancer after previously being treated in 1999.