The groundbreaking blood test could save thousands of patients a grueling chemo each year

A blood test that detects traces of cancer cells could save thousands of patients a year from grueling chemotherapy.

Researchers at a leading NHS hospital are studying whether it can be used to show if surgery has removed gut tumours.

They say that half of patients with stage three colorectal cancer are cured by surgery alone and are unnecessarily overtreated with intravenous chemotherapy after their surgery.

About 1,600 colorectal cancer patients are being recruited for the UK study, which is being led by the Royal Marsden Hospital in London.

The blood tests look for microscopic traces of cancer in the bloodstream, called circulating tumor DNA.

The presence of these marks, which are invisible on scans, indicate whether or not the patient was cured by their surgery.

dr Naureen Starling, the study’s lead investigator, said the study’s outcome could impact the way thousands of colorectal cancer patients are treated each year.

“Half of the patients with stage 3 colorectal cancer are cured with surgery alone, so we overtreat a large proportion of patients,” she told the BBC.

The hope is that this particular technology could spare many cancer patients unnecessary chemotherapy.

“It’s good for the patient, it’s good for healthcare, it’s good for cost savings within the NHS. That would be a win-win situation,” added Dr. Starlings added.

The study, called TRACC, uses a test developed by US company Guardant Health.

Samples are sent to their labs in California for analysis, with results coming back within two weeks.

The study will examine whether there is a difference in three-year survival rates between the patients treated with the blood test as compared to the standard-of-care chemotherapy group.

Trials are also underway in the UK to monitor patients with lung and breast cancer in the same way.

dr Starling said the potential for this new test across cancer care is “immense,” not just when it comes to detecting residual disease after surgery, but also for early detection.

Ben Cooke, 52, who runs a hair salon in Chelsea, London and also works as a stylist for fashion shoots, is attending the process.

In early March last year, he noticed dark blood in his stool. He called NHS 111 and was sent to A&E.

He was diagnosed with stage three colon cancer, which was successfully treated with surgery.

The gold standard treatment is to undergo intravenous chemotherapy afterwards to remove any remaining tumor cells and reduce the risk of the cancer coming back.

But the chemotherapy used for colon cancer, oxaliplatin, can cause painful tingling and numbness in the hands and feet, called peripheral neuropathy.

This nerve damage can be long-term, and Ben was concerned it might affect his ability to do the work he loves.

He told the BBC: “I wouldn’t be able to cope with that. I have to work – it’s my therapy.”

His test showed he was cancer-free, so he avoided intravenous chemotherapy.

Instead, like all study participants, he took an oral chemo tablet twice a day.

This had minimal side effects and allowed him to continue working.

“The fact that I didn’t have any tingling in my hands was just an absolute blessing,” he added.

A study of 455 colorectal cancer patients presented at a major cancer conference last year found that using blood tests to guide treatment could halve the number of patients who need post-operative chemotherapy without the risk of recurrence.

But dr Starling says her much larger randomized study is essential to calibrating exactly how much reliance can be placed on liquid biopsies.