Influential American billionaire Warren Buffett has been diagnosed with early-stage prostate cancer, it has been revealed.
The 81-year-old financial guru has tried to reassure his company's shareholders that the condition is "not remotely life-threatening".
In a letter, the boss of Omaha-based investment firm Berkshire Hathaway said that a two-month radiation treatment he and his doctors plan to start in mid-July will restrict his travel but not his routine.
"I feel great - as if I were in my normal excellent health," Mr Buffett, dubbed the Wizard of Omaha, said.
"And my energy level is 100%. I discovered the cancer because my PSA level (an indicator my doctors had regularly checked for many years) recently jumped beyond its normal elevation and a biopsy seemed warranted."
He said the tests showed no indication of cancer elsewhere in his body.
"The chance of dying of prostate cancer for Mr. Buffett in the next 10 years is probably 2% or 3%, so the prognosis is great," Dr Ralph deVere White, director of the Comprehensive Cancer Centre at the University of California, said.
A number of innovative approaches to prostate cancer are now employed, including ultrasonic beam treatment.
A self-made billionaire, Mr Buffett is known for a no-nonsense approach to investing and as one of the world's richest men has become one of its most generous philanthropists.
His personal stake in Berkshire Hathaway was valued at $44.6bn (£28bn), before the cancer announcement was made after markets closed on Tuesday.
Famously frugal, Forbes magazine ranks him as the second richest American.
Mr Buffett has developed a succession plan for when he finally departs from the firm which has weathered the global financial crisis.
He told shareholders in February that the board has chosen someone to succeed him as boss - someday - and he said there are two backup candidates.
None of the three has been publicly identified and Mr Buffett has said Berkshire Hathaway has not even told the successor and backups who they are.