Blood test could help screen for colon cancer

Research shows that discovery of ‘telltale’ antibodies could indicate need for further tests and treatment

PATIENTS WITH colorectal cancer have telltale signatures of antibodies in their blood, according to new research from Beaumont Hospital and the Royal College of Surgeons in Ireland and Dublin City University.

The findings, which were published in Gut, the international journal of gastroenterology and hepatology, could pave the way towards a blood test to help identify when a patient has the disease.

The study looked at patients whose symptoms warranted a colonoscopy, where a camera is used to check the inside of the intestine for cancerous growths.

Consenting patients also gave blood samples, which the researchers then ran over large “protein arrays” to pick out antibodies present in the blood serum.

Then they related those signatures to the patient’s ultimate diagnosis, explained Dermot Kenny, professor of cellular and molecular therapeutics at RCSI.

“These were people who were all going for a colonoscopy because of a suspicion of significant disease,” he said.

Of the patients selected to take part in the study, the colonoscopy showed that 43 had colorectal cancer and 40 did not.

“We compared the antibody profiles between the two groups and we found there were certain antibodies that occurred commonly in the patients who turned out to have cancer, but those antibodies didn’t occur in the normal controls,” said Prof Kenny.

“Interestingly, there were also antibodies in the normal that disappeared in the patients with cancer.”

Those differences could help identify patients in need of further investigation for tumours, he added.

“As a clinician there’s no indicator as to whether a patient should have a colonoscopy.

“So with this you could take a blood test that would say the probability that someone has cancer is very low or it’s very high, and then you can stratify patients.”

Patients showing high levels of cancer-associated antibodies could be put forward for appropriate assessment and treatment, and it would help patients showing low risk in the blood test to avoid undergoing an unnecessary colonoscopy.

“If your profile showed that you had these antibodies that indicate wellness and no antibodies that indicate cancer, the doctor could say come back and see me in a few months,” he said.

The research was funded by Science Foundation Ireland and through the Higher Education Authority and the team is currently seeking additional funding to move towards a version of the test that could be used clinically, added Prof Kenny.

“The original research was a very complex, long study that involved a lot of people and technology. Now we have to get that test down into a readily usable form.”