The singer was told he has stage four glioblastoma after he had two seizures over the summer.
The 32 year old opened up about his diagnosis in a joint OK magazine interview with his wife Kelsey, who is currently 36 weeks pregnant with their second child.
Tom was told the news after being admitted to hospital following a second seizure during a family holiday in Norwich in August.
“They pulled the curtain around my bed and said, ‘It’s a brain tumour.’ All I could think was, ‘F*****g hell!’ I was in shock,” he said.
“It’s stage four glioblastoma and they’ve said its terminal. It was a lot to deal with by myself. I still haven’t processed it.”
Kelsey, who was unable to be with Tom in hospital due to the coronavirus pandemic, said: “It was horrendous. They rang me and told me over the phone. They said, ‘It’s a tumour and it’s worst-case scenario’.
“They also told us it was inoperable and what the treatment would be. I was in a complete state.
“It was like everything stopped. Obviously being told you have any tumour is bad, but to be told you have the worst one is a lot to take in. All I could think was, ‘What’s going to happen and what is our life now?’”
Tom has declined to know his prognosis, and is currently undergoing back-to-back chemotherapy and radiotherapy treatment for six weeks, with the weekends off.
He has vowed that he is “going to fight this all the way”, explaining he and Kelsey, who are also parents to 15-month-old daughter Aurelia, are “already exploring alternative treatments and looking at clinical trials both here and abroad”.
He said: “There are so many stories of people who were given a bad prognosis and are still here five, 10, even 15 years later. We’re going to fight this all the way.”
The full interview with Tom and Kelsey appears in this week’s OK magazine.