Robson has been battling a fifth bout of the illness and has accepted doctors' prognosis that he is unlikely to beat it.
Robson said: 'I have accepted what they have told me and I am determined to make the most of what time I have left.
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'I am going to die sooner rather than later. But then everyone has to go some time, and I have enjoyed every minute.
'I have been fortunate to survive this long. It is thanks to the doctors and their dedication,' Robson told The Sun.
Sir Bobby, who took England to the brink of a World Cup final in Italy in 1990, has enjoyed a football career spanning six decades - from playing days with Fulham and England, to managerial triumphs first with Ipswich and then as national coach at two World Cups, to continental coaching appointments.