A cancer sufferer has told how he almost died due to delays in diagnosing his illness when he was a teenager.

Anthony Whitehead, from Blewbury, near Didcot, explained that as an 18-year-old it took repeated visits to doctors before they realised he was suffering from non-Hodgkins lymphoma. The diagnosis took three months.

After receiving treatment at the John Radcliffe Hospital in Oxford, he recovered and is now in remission.

Mr Whitehead, now 21, is backing a campaign by the Teenage Cancer Trust to highlight delays in treatment for teenage cancer sufferers.

He said: "I was showing all the classic signs of the disease - I had a rash, I started getting fevers and I was losing a lot of weight - but I had to go to the doctor countless times.

"The GP thought I was not eating properly and at one point thought I had glandular fever.

"When I could no longer get out of bed my dad said 'this is ridiculous' and drove me to hospital and I stayed there for about three weeks.

"If I had not started chemotherapy when I did I might have died - I was quite close to the edge.

"If GPs are in any doubt, they need to refer teenagers to hospital for treatment as soon as possible."

In April, Mr Whitehead, a psychology student at Brighton University, appeared on stage with rapper Prince Aidoo at a Royal Albert Hall concert for the Teenage Cancer Trust.

Three studies presented at Teenage Cancer Trust's Fifth International Conference on Teenage and Young Adult Cancer Medicine focused on the extent of delays teenagers and young adults can face before being diagnosed with cancer.

Tim Eden, Teenage Cancer Trust Professor of TYA Cancer at Manchester University, told the conference on Monday that in a study of 115 patients with bone tumours, the time between the first symptom and a diagnosis ranged from four to 184 weeks, with the average time being 15.2 weeks.

A second study looked at 95 patients with a variety of tumours and found that the symptom interval ranged from two to 192 weeks, with the average length being 9.5 weeks.

A third study by Sam Smith, a TYA nurse consultant in the Teenage Cancer Trust Unit at Manchester's Christie Hospital, showed that out of 207 young people, four out five sought medical help very quickly and only seven per cent delayed for a matter of months.

About half of the patients with Hodgkins lymphoma, brain and bone cancers had to visit their GP four or more times before being referred to a specialist.

Prof Eden said: "It would seem to be important to raise awareness among professionals to recognise worrying signs and to trigger them to be more rapid in their response."

Cancer is the most common disease causing death in the 15-24 age range, accounting for 11 per cent of all deaths.

Tracey Rees, head of specialist commissioning for Oxfordshire Primary Care Trust, said: "Fortunately, GPs see few young people with cancer but this can make it hard for them to recognise signs and symptoms when they do.

"The 'Referral Guidelines for Suspected Cancers' was a start. It should be helping GPs identify those patients who are most likely to have cancer and therefore require urgent assessment by a specialist. In Oxfordshire the local focus is via the county cancer steering group of GPs, consultants and other NHS professionals."