Status Quo's Rick Parfitt has admitted he is struggling to give up smoking as he prepares for tests on a tumour in his right vocal cord.
Doctors have ordered a biopsy on Parfitt's throat
The band have had to cancel their UK tour after doctors ordered a biopsy to determine if the growth is malignant.
Parfitt, 57, told the Sunday Mirror he was "terrified" when he heard the news as he still smokes 20 cigarettes a day.
The singer and guitarist underwent a quadruple heart bypass operation in 1997 after doctors warned he could die.
Parfitt was warned off a hard-living lifestyle involving drugs and alcohol. He told the newspaper he had not given up drink, but had stopped taking drugs.
"It is really scary," he said. "I would be lying if I said it wasn't - but at the moment, we don't know anything.
"I've just got to see what happens this week before making any big decisions. It's a question of wait and see.
"When the doctor said there was a tumour, I was terrified. But then he said it doesn't necessarily mean it's cancer."
Parfitt said he gave up smoking for 10 months last year, but had only recently returned to the habit.
Status Quo joined the cast of Coronation Street as guest stars
He blamed it on the "stresses and strains of showbusiness", but has now said he will "knock it on the head - once and for all".
Parfitt is at home in Teddington, west London, preparing for the tests with his former wife Patty and son Harry, 15.
He and his band partner Francis Rossi are celebrating 40 years together and recently made two guest appearances on Coronation Street, playing themselves.
Status Quo have scored more hit singles than any other band in UK chart history, with 61 chart hits since their first smash, Pictures of Matchstick Men, was released in 1968.
Among their best-known songs are their British chart topper Down Down in 1974 and Rockin' All Over The World in 1977.