There is a simple home test to detect bowel cancer, but new figures from Cancer Australia show only two in five of those eligible for free home screening are actually taking the test.
The chief executive of Cancer Australia, Helen Zorbas, says it is a growing concern.
"The results are disappointing, because we have a test that's potentially life-saving, in relation to bowel cancer, which is the second most common cancer in Australia and the second-highest cause of cancer death in Australia," she told SBS World News.
"But our latest figures from the Australian Institute of Health and Welfare tell us that only two of five people who are eligible and who are sent the test for screening actually take up that offer for screening."
Some specific groups are even less likely to be tested, including those from non-English speaking backgrounds.
Dr Zorbas says that is a real concern because bowel cancer survival is significantly improved when the disease is detected and treated early.
"What we can gleen from the data that we do have is that Aboriginal and Torres Strait Islander people and people from non-English speaking backgrounds are less likely to take up the offer of screening compared with other Australians," she said.
"The government is certainly looking at ways in which to meet the needs of those particular demographic groups and try and improve the communication around the importance of screening."
The incidence of bowel cancer is increasing in Australia, with almost 17,000 people expected to be diagnosed this year.
Men are more likely to be diagnosed and die from bowel cancer, but they are also less likely than women to participate in bowel cancer screening.
The National Bowel Cancer Screening Program urges people between ages 50 and 74, eligible for a free bowel cancer screening, to make use of it.
Sydney man, Colin Brown, who was diagnosed with bowel cancer in 2014, credits the test with saving his life.
"As I said to my surgeon, if it hadn't been for the test, I wouldn't have been placed in his very capable hands, and I do believe quite strongly that I would be dead today if I hadn't undertaken that test," he said.
He's urging others to do the same.
"I think men would be embarrassed by having to undertake the test. It can be an embarrassing process to undertake. Well, some men may think it's an embarrassing test to undertake," he said.
"In fact, it's not. It's quite simple, it's quite quick, and I'd rather be alive than dead and embarrassed."
There are risk factors for bowel cancer which can be addressed.
They include obesity, lack of physical activity, inadequate dietary fibre, a high intake of foods such as processed meat, high alcohol consumption and smoking.
Other risk factors include a personal history of bowel polyps and a family history of bowel cancer.
The Australian Medical Association (AMA) urges all people, not just those over age 50, to be alert to symptoms which may indicate a problem.
AMA Vice-President Dr Tony Bartone points to three signs in particular.
"It's important to realise that, even though this screening program is looking specifically at 50- to 74-year-olds, the symptoms of bleeding from the back passage and/or unexplained weight loss or a change in bowel habits need to be followed up and need to be discussed with your doctor."
Cancer Australia says if bowel cancer is detected at the earliest stage, the five-year survival rate is 93 per cent.