Australian researchers have made a breakthrough in detecting bowel cancer without a stool test.
In research published on Wednesday, a team from the South Australian Health and Medical Research Institute, University of Adelaide and Columbia University in the United States discovered that a probiotic bacteria already used to treat gut disorders can be engineered to find early bowel cancer tumors.
Currently, bowel cancer can only be diagnosed with a fecal occult blood test (FOBT), which looks for invisible traces of blood in a stool sample.
The Australian-led research team found that the bacteria Escherichia coli Nissle, a probiotic first described by German physician Alfred Nissle during World War I, prefers to live in the precursor lesions to bowel cancer and bowel cancer tumors when they are present in the gut.
They then engineered the bacteria to release molecules that illuminate early cancers.
Susan Woods, a leading researcher, said the breakthrough could help diagnose bowel cancer earlier and non-invasively.
"Once the bacteria locates the tumor it releases a marker that we can then detect in urine, which shows cancer is present," she said in a media release.
"In the future, we're aiming to be able to detect this marker in a blood test."
According to the Cancer Council, bowel cancer is the fourth-most commonly diagnosed cancer in Australia, with an estimated 15,300 diagnoses in 2023.
The average age at diagnosis is 69 years. Every Australian aged 50-74 is sent a free FOBT done at home every two years under the National Bowel Cancer Screening Program.