Page URL:

Cancer blood-test launch raises eyebrows

14 September 2015
Appeared in BioNews 819

A US startup called Pathway Genomics has launched the first commercial 'liquid biopsy' to identify cancerous mutations via a blood test.

Pathway will market directly to healthy people who have a high risk of developing cancer and claim that they can help people achieve an early cancer diagnosis – for $699 (£450).

For that money, the CancerIntercept test will look for 96 mutations in nine major cancer-driver genes whose presence could come from circulating tumour DNA, released from dying cancer cells.

'It's like a cancer stethoscope,' explains the promotional video on Pathway's website.

However, while the graphics may be flashy, the data are less eye-catching. In fact, there are none because Pathway has not yet published evidence in any peer-reviewed journals, nor is the test approved by the FDA.

Consequently, some health professionals are cautious about the test. Professor Keith Stewart, head of the Mayo Clinic's Center for Individualized Medicine, voiced his concerns to Bloomberg Business.

'It's fair to say it's a little premature,' said Professor Stewart, noting that 'there could be a significant risk for false-negatives or false-positives.'

False-positives could result in a user being given an incorrect and worrying diagnosis of cancer and seeking out unnecessary medical intervention; a false negative could result in someone being wrongly told they are cancer-free.

Dr Isaac Garcia-Murillas, an oncologist at the Institute of Cancer Research in London who has been working on a blood test that may predict breast-cancer relapse (see BioNews 817) told The Verge: 'I am very reticent to believe a privately funded personal genomics company's claims when there is no peer-reviewed data to support their tests or technical approaches.'

To calculate the validity of a new diagnostic test typically requires thousands of people, millions of dollars, and many years of study. Pathway's research has not yet reached this large scale.

The company's CEO, Jim Plante, admitted to The Verge that their test pool numbered only 'hundreds of samples' – and these were mostly from patients with advanced cancer, not undiagnosed people – and they have yet to complete a long-term study.

If validated, a reliable and affordable 'liquid biopsy' for cancer would represent a major breakthrough in biotechnology research. A noninvasive, low-cost test could also be used to screen large groups of people.

Ultimately, until Pathway publishes its data, it is impossible to evaluate the effectiveness of this particular test. Its chief medical officer, Glenn Braunstein, insists it has internal studies that 'will be submitted for peer review in the future'.

Consumer Blood Test to Detect Cancer Hits Market Amid Skepticism
Bloomberg |  10 September 2015
Pathway Genomics Launches First Liquid Biopsy Test To Detect Cancer-Associated Mutations In High-Risk Patients
Pathway Genomics |  10 September 2015
Pathway launches 'liquid biopsy' to find cancer in healthy people
Reuters |  10 September 2015
Startup claims its test finds cancer early, but where’s the evidence?
The Verge |  10 September 2015
Why You Shouldn’t Bother with a $699 Cancer Test
MIT Technology Review |  10 September 2015
13 March 2017 - by Dr Loredana Guglielmi 
Researchers have developed a new blood test that can not only detect cancer at an early stage, but can also indicate where the tumour is located in the body...
19 December 2016 - by Isobel Steer 
A study has cast doubts on the reliability of 'liquid biopsies' – blood tests that detect tumour mutations and are increasingly used to guide treatment...
12 September 2016 - by Meetal Solanki 
A blood test costing only £35 could help in the early diagnosis of oesophageal cancer and could be available in five years' time...
21 March 2016 - by Dr Hannah Somers 
Scientists say they have been able to detect multiple diseases, including pancreatic cancer, multiple sclerosis and type 1 diabetes, by analysing fragments of DNA in the bloodstream...
14 March 2016 - by Dr Lucy Freem 
Scientists have developed a blood test that captures tumour DNA from stray cancer cells circulating in the blood and allows them to monitor genetic changes in skin cancer...
1 September 2015 - by Dr Hannah Somers 
Scientists have developed a blood test that can predict several months in advance which breast cancer patients will relapse.
13 April 2015 - by Dr Ainsley Newson and Associate Professor Stacy Carter 
In March, Sequenom revealed that its MaterniT21 non-invasive prenatal test has detected potential cancer in some pregnant women. This is a good thing, right? Women in the prime of their lives receiving information that may catch a cancer early. But, we suggest, it is not this simple. ...
9 March 2015 - by Kirsty Oswald 
US company Sequenom has revealed that its prenatal blood test - MaterniT21 PLUS - has detected potential cancer in at least 40 expectant mothers since its launch three years ago...
15 July 2013 - by Julianna Photopoulos 
Scientists have developed a 'barcode' blood test that reads genetic changes to pick out the most aggressive prostate cancers...
18 March 2013 - by Dr Nicola Davis 
A blood test is being developed that could help doctors monitor how breast cancer tumours respond to therapy...
to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions

Syndicate this story - click here to enquire about using this story.