A simple blood test can accurately detect the beginning stages of two common cancers long before symptoms appear, scientists claim.
An initial study found the test had a 95 per cent success rate in detecting cancer in participants, including those with breast cancer in stages 0 and 1 and those with lung cancer in stages 1 and 2. Stage 2 is when patients typically begin to display symptoms and are most often diagnosed.
Mammograms: Regular breast screenings are used to detect cancer early in women deemed at high risk. Now scientists think a blood test could help
The researchers, from Kansas State University, said they were close to testing for pancreatic cancer as well.
The test works by detecting increased enzyme activity in the body, which indicates illness. When enzymes from the patient's blood or urine are mixed with certain amino acids along with a dye, cancers produce a specific pattern or signature.
Test developer Professor Deryl Troyer, said: 'We see this as the first step into a new arena of investigation that could eventually lead to improved early detection of human cancers.
'Right now the people who could benefit the most are those classified as at-risk for cancer, such as heavy smokers and people who have a family history of cancer.
'The idea is these at-risk groups could go to their physician's office quarterly or once a year, take an easy-to-do, noninvasive test, and be told early on whether cancer has possibly developed.'
The researchers say the test would be repeated a short time later. If cancer is confirmed, diagnostic imaging could begin that would otherwise not be routinely pursued.
According to the American Cancer Society, an estimated 39,920 breast cancer deaths and 160,340 lung cancer deaths are expected in the U.S. in 2012.
With the exception of breast cancer, most types of cancer can be categorized in four stages based on tumor growth and the spread of cancer cells throughout the body.
Breast and lung cancer are typically found and diagnosed in stage 2, the stage when people often begin exhibiting symptoms such as pain, fatigue and coughing. Numerous studies show that the earlier cancer is detected, the greater chance a person has against the disease.
'The problem, though, is that nobody knows they're in stage 1,' said co-developer Professor Stefan Bossmann said.
'There is often not a red flag to warn that something is wrong. Meanwhile, the person is losing critical time.'
The test developed by Kansas State University's Bossmann and Troyer works by interpreting enzyme patterns or signatures, found in a patient's blood or urine.
'These enzyme patterns can also help distinguish between cancer and an infection or other diseases that commonly occur in the human body,' Prof Bossmann said.
'For example, a person who smokes a lot of cigars may develop an inflammation in their lungs. That will drive up some of the markers in the test but not all of them.
'Doctors will be able to see whether there was too much smoke inhalation or if there is something more serious going on. False-positives are something that we really want to avoid.'
A breast scan using thermography is another way of detecting cancer
In addition to early detection, researchers say the test can be tweaked to monitor cancer. For example, patients being treated with drugs can be observed for drug effectiveness. Similarly, doctors can use the dye in the test to determine if the entirety of a tumor has been successfully removed from a patient after surgery.
Researchers evaluated the test's accuracy on 32 separate participants in various stages of breast or lung cancer. Data was collected from 20 people with breast cancer - ranging in age from 36 to 81 years old - and 12 people with lung cancer - ranging in age from 27 to 63 years old.
Twelve people without cancer were also tested as a control group. This group ranged in age from 26 to 62 years old.
A blood sample from each participant was tested three times. Analysis of the data showed a 95 percent success rate in detecting cancer in participants.
Bossmann and Troyer have designed a second testing method that is anticipated to produce the same results in about five minutes. The team recently received £189,000 in funding for the project.
Tests detecting for pancreatic cancer and triple-negative breast cancer are anticipated to begin in October.