The presenter of BBC Radio 4's World at One programme, Nick Clarke, has been diagnosed with cancer.
Nick Clarke has won awards for his broadcasting
Clarke, who has presented the show since 1989, will need surgery involving the loss of a leg but is expected to make a full recovery from the cancer.
Helen Boaden, head of BBC News, said in a statement: "We're very sorry indeed to hear this news and send him - and his family - our very best wishes."
Clarke said he hoped to be back at work in the summer.
As well as presenting the World at One, Clarke also chairs Any Questions and Any Answers when Jonathan Dimbleby is away, the Round Britain Quiz and the debate series Straw Poll.
After a career in newspapers, he joined BBC in 1973 as Northern Industrial Correspondent before moving on to the Money Programme and eventually joining Newsnight in 1984.
Clarke won the Broadcasting Press Guild broadcaster of the year award in 2001 and has recently published a biography of the veteran writer and journalist Alistair Cooke.