Queen guitarist Brian May underwent a scan on Monday as part of a series of urgent tests sparked by fears he could have cancer, the rock star revealed on his website.
The 66-year-old suffered agonising back and hip pain earlier in December which left him barely able to stand, and MRI scans revealed "some abnormalities in the bones -- things that the report said needed urgent attention", he wrote.
"So around Christmas I've been having a succession of blood tests, ultrasounds, and various kinds of scans, to see if they could rule out various kinds of cancer," he wrote.
One of the scans was due on Monday, he said in the blog posting on brianmay.com dated December 28.
May said he was trying to be optimistic, as his doctors had told him that any cancer they might find would likely be treatable with success.
"Now, on hearing the 'C' word something happens inside you... of course. I've seen so many of my dear friends fighting it... and my dad lost his battle at age 66, exactly the age I am now," he wrote.
"So over the last few days I've been in various states of unrest."
But in a blog update on Monday, May said he was "overwhelmed by the amazing messages" of support from fans, adding: "I thank you all from the bottom of my heart."
May was a founder member of Queen, the world-famous rock group fronted by Freddie Mercury until the singer died as a result of AIDS in 1991. May penned the hit single "We Will Rock You".