New testing method can catch cancer very early

By Mark Waghorn via SWNS

Simple blood tests developed in New York can detect more than 50 types of cancer before any clinical signs or symptoms of the disease emerge.

They open the door to identifying previously hard-to-find tumors for removal before they spread.

It offers hope of beating 'silent killers' such as those of the head and neck, ovaries, pancreas, gullet, prostate and cervix.

The technique called MCED (multi-cancer early detection) looks for DNA fragments that leak into vessels and arteries.

They carry chemical changes that differ from normal cells - indicating disease. It offers hope to screening programs for older people - and other vulnerable individuals.

One trial, called PATHFINDER, picked up a signal in 1.4 percent of 6,621 over 50s who were believed to be healthy - and where it had come from in the body.

A resolution was achieved within three months for almost three-quarters of those who tested positive. Cancer was confirmed in 38 percent of cases.

It took an average of 79 days to diagnose - or decide there was no evidence of malignancy requiring further investigation.

Of 6,290 individuals who were cancer-free, over 99 percent received a negative test result.

Senior author Dr. Deb Schrag, of Memorial Sloan Kettering Cancer Centre, New York, said: "The results are an important first step for early cancer detection tests because they showed a good detection rate for people who had cancer and an excellent specificity rate for those who did not have cancer.

"In people with a positive test, it took less than two months to confirm the diagnosis if they had cancer and it took a bit longer if they did not have cancer primarily because physicians opted to perform imaging studies and then repeat them a second-time several months later to investigate the possibility of a cancer diagnosis."

She added: "An important finding was that few participants with a false positive screening test required multiple invasive procedures such as endoscopies and biopsies.

"This finding should help to allay concerns that these tests could cause harm by generating unnecessary procedures in people who are well."

The study reported at a European Society for Medical Oncology meeting in Paris (ESMO) is the first to show an MCED test can detect cancer in undiagnosed patients.

England's National Health Service is currently piloting a blood test for more than 50 cancers after enrolling 140,000 asymptomatic people to investigate its clinical effectiveness.

ESMO co-chair Professor Fabrice Andre, of Gustave Roussy Cancer Cancer, Villejuif, France, said the technology is set to revolutionize therapy.

He said: "It is a duty of professional societies like ESMO to raise awareness of the fact that within the next five years, we will need more doctors, surgeons and nurses, together with more diagnostic and treatment infrastructure, to care for the rising number of people who will be identified by multi-cancer early detection tests.

"We need to agree on who will be tested and when and where tests will be carried out, and to anticipate the changes that will happen as a result of these tests, for example in the diagnosis and treatment of people with pancreatic and other cancers that are usually diagnosed at a much later stage."

Dr. Schrag stressed the importance of continued standard screening for breast and colorectal cancer while MCED tests are being refined and validated.

Currently, there are no such options for pancreatic, small bowel and stomach tumors - which often migrate to other organs before diagnosis.

Dr. Shrag said: "This study indicates hope is on the horizon for detecting cancers that are currently unscreenable, but of course, much more work is needed and, with experience and larger samples, these assays (tests) will improve.

"The tests need to be refined so they are better at distinguishing tumor DNA from all the other DNA that is circulating in the blood.

"It is also critical to note that the purpose of cancer screening is not to decrease the incidence of cancer, but rather to decrease cancer mortality.

"It is premature to reach any conclusions about how MCED testing affects mortality which was not measured in the PATHFINDER study and requires lengthy follow-up."

Prof Andre added: "We need comparative trials across all types of cancer to find out if having an early detection test affects morbidity and mortality.

"We also need to know how the tests benefit patients, and how to discuss the results with them.

"In addition, we need to know more about the small proportion of false positive tests - MCED results that indicate cancer is present but this is not confirmed by standard diagnostic procedures.

"We need some of these answers before we can calculate the cost impact of introducing MCED tests in routine clinical practice."