Sir Bobby Robson has been diagnosed with cancer for the fifth time.
Robson has undergone cancer surgery four times over 15 years
Doctors have discovered that the 74-year-old former England manager has small cancerous nodules in his lungs.
"My last operation in August was a success but this time the doctors can't operate," said Robson, who has started a six-week course of chemotherapy.
"The good news is that they are measuring the nodules in my lungs in millimetres rather than centimetres," Robson told the Mail on Sunday.
Robson has battled the disease on and off for the last 15 years, having undergone cancer surgery four times.
Currently acting as a consultant to Republic of Ireland coach Steve Staunton, Robson added: "We're hopeful the treatment will keep it under control."
The son of a Durham miner, Robson was knighted in 2001.
He won 20 England caps, playing in the 1958 and 1962 World Cups, before taking the team to the semi-finals of the 1990 World Cup in an eight-year spell as the national manager.
He made his name as a manager at Ipswich, winning the FA Cup in 1978 and the Uefa Cup in 1981.
After leaving the England job in 1990, Robson then managed a string of top European clubs including PSV Eindhoven and Barcelona.