Laurence Ball, who lives in Shetland, had surgery at Aberdeen Royal Infirmary to remove a tumour on his lung.
But Mr Ball, 58, was later told there had never been cancer in the organ. He is now planning legal action.
NHS Grampian said the case was in the hands of the Central Legal Office and the board considered it inappropriate to comment further.
The problems started when Mr Ball suffered a chest infection in May 2005 and was sent for tests at Aberdeen Royal Infirmary.
He was told he had cancer in his left lung and underwent surgery in August 2005 to have a tumour removed.
But after the operation he was told by surgeons that he did not need chemotherapy as there had been no cancer in his lung.
"For the next few days I was really traumatised and in deep shock," he told BBC Radio's Good Morning Scotland programme.
Mr Ball said his solicitor had been told by NHS Grampian that an investigation had found no individual blame, incompetence or negligence.
However, Mr Ball said he had "lost everything" - his job as a firefighter, his health and the years of happy retirement ahead.
He said: "I was given a misdiagnosis, I've lost my lung and I lost my job.
"For those reasons I feel that at the very least an explanation should be given to me by the Grampian health board who should sit down and discuss financial compensation for my loss of earnings."