Beyonce’s dad has said it was “tough” telling her he had been diagnosed with breast cancer.
The talent manager, 67, revealed last month that he had undergone surgery this year after discovering he had the disease.
Opening up about his diagnosis on Good Morning Britain, Mathews said he had found out he had a BRCA2 mutation, which he said means he has a higher risk of prostate cancer, pancreatic cancer and melanoma.
Asked what it was like having to tell his daughters Beyonce and Solange, he said: “It was tough to have to tell them that.
“But genetically it’s all my family members.
“I had to talk to my sister, I had to talk to my nieces, my grandson.
“Everyone is affected by this."
He went on: “My daughters love their father obviously and I love my daughters.
“The love there and the care and family, it’s always good to have family in these tough times.”
Knowles, who was the manager of Beyonce’s group Destiny’s Child, said his children know that he is “a fighter”.
“I’m also very cautious - it’s a lifestyle change,” he added.
“I stopped drinking, I’m working out more, losing weight. All of those things.”
Knowles said his first symptom was discharge from the nipple so he went to the doctor to have a mammogram and a biopsy.
He told hosts Ben Shephard and Kate Garraway: “We found out that it was cancerous at an early, early stage, stage 1A and had surgery and hopefully will have a full recovery.”
According to Cancer Research UK, there are about 390 men diagnosed with breast cancer each year in the UK. This compares to around 54,800 cases in women.