Blood test for lung cancer
A test which could mean many more people get early treatment for lung cancer is being developed by scientists.
More than nine out of ten people diagnosed with lung cancer die, and it kills more people in the UK than any other type.
There are chemotherapy treatments available, but delays in diagnosis often reduce the already slim chances of a cure.
German researchers believe they have found a molecule which is found in high concentrations in the blood of people with advanced lung cancer.
This potentially opens the door for a blood test which could spot cases much earlier than at present.
This would give treatments the best chance of success.
The molecule, called pleiotrophin, was found at 11 times greater concentrations in the blood of lung cancer patients than in healthy people.
Four out of five lung cancer patients had noticeably raised levels of the chemical.
The team looked at 85 patients with two different types of lung cancer, comparing their pleiotrophin levels wtih 41 apparently healthy volunteers.
Only one out of the 41 had elevated levels - compared to 87% of patients with small cell lung cancer patients and 63% of those with non-small cell lung cancer.
Higher levels of the molecule seemed to correspond with how advanced the disease was.
Compared to early lung cancer patients, levels were 62% higher in the "advanced" group.
Dr Gerhard Zugmaier, who led the research, said: "Lung cancer is often diagnosed too late - and a blood test that could detect early signs of the disease would be a real step forward.
"If large-scale research confirms our results, then testing for the molecule could help in diagnosing the disease."
The molecule could also one day be a guide to how well the patient has responded to treatment.
In patients whose lung cancer responded to treatment, levels of the molecule dipped, but in those whose cancer appeared to respond, then returned, the levels rose again accordingly.
Professor Gordon McVie, the joint director general of Cancer Research UK, said: "Lung cancer has to be detected early to increase the chance of successful treatment.
"This research, while at an early stage, could be an important step towards a future diagnostic test."