Michael Bolton opened up to PEOPLE about his battle with brain cancer.

The two-time Grammy winner revealed he was diagnosed with glioblastoma in December 2023.

“You’re reaching into your resources and your resolve in a way that you never would have thought,” Bolton said. “Succumbing to the challenge is not an option. You’re really quickly drawn into a duel. I guess that’s the way you find out what you’re made of.”

Since beginning treatment, he has experienced issues with his short-term memory, speech and mobility.

Bolton had a tumor removed in January 2024, then had a second surgery the next month due for an infection. He had radiation and chemotherapy treatments until October 2024.

He said he has a “heightened sense of appreciation” for life.

“It’s unthinkable for it to be OK not to make the most of your life,” he said. “I think we develop capabilities and problem management, and we learn how to make the best out of a bad situation. You have to be a cheerleader for yourself.”

Bolton, who has three daughters — Isa, 49, Holly, 47, and Taryn, 45, reflected on family and legacy in light of his fight.

“How do I give things that they can take forward?” he asked. “Life lessons, love, any kind of validation that I can give (them) — I want to be on the right side of that so they feel great about who they are. It’s a reality of mortality. Suddenly a new light has gone on that raises questions, including ‘Am I doing the best that I can do with my time?’”

Bolton continued to lean on his music.

“I want to keep going,” he said. “I feel there’s still a lot to do on the fight side,” he said. “I got a title for a song: ‘Ain’t Going Down Without a Fight.’”

Glioblastoma is a type of cancer that grows in the brain and spinal cord, per the Mayo Clinic.

Check out the full interview at PEOPLE.

Mark Heim is a reporter for The Alabama Media Group. Follow him on Twitter @Mark_Heim. He can be heard on “The Opening Kickoff” on WNSP-FM 105.5 FM in Mobile or on the free Sound of Mobile App from 6 to 9 a.m. daily.