Impact

Bowel cancer is the second most commonly diagnosed cancer in Australia. One in 22 Australian men and one in 30 women will develop bowel cancer before the age of 75.^[1] In 2015, 15,604 new cases of bowel cancer were reported – 8573 in men and 7031 in women – representing around one in every 13 new cases of cancer diagnosed in Australia (excluding non-melanoma skin cancer).^[1]

Although the rate of bowel cancer diagnoses is projected to decrease in men and remain stable in women, the expected increase and ageing of the population mean the projected number of cases will continue to rise.^[2]

Bowel cancer is the second most commonly diagnosed cancer overall, as well as the third most common cause of death from cancer in men (after lung and prostate cancers) and the third most common in women (after lung and breast cancers).^[3] In 2016, there were 5375 deaths in Australia from bowel cancer: 2936 in men and 2439 in women.^[1] However, this does not include deaths due to malignant neoplasm of intestinal tract (part unspecified) and may be an underestimation of bowel cancer deaths.^[4] The rate of bowel cancer deaths declined steadily over the 20-year period from 1989–2012.^[1] Despite the trend towards improved survival, bowel cancer remains an important cause of premature death in Australia.

In Indigenous communities, where incidence rates are believed to be under-recorded, bowel cancer is the third most common cancer affecting both men and women.^[5] The survival rate from bowel cancer is lower for Indigenous than non-Indigenous Australians.^[6] It is also recognised that Indigenous Australians often have co-morbidities that may hinder the effectiveness of cancer treatments.^[7]

Economic costs

Australian Institute of Health and Welfare data on bowel cancer expenditure in Australia estimated that bowel cancer cost the Australian health system $460 million in 2008-09 – making it the nation’s most expensive cancer.^[8] Of this, $388 million was spent on hospital inpatient services, compared with $33 million on bowel cancer screening.^[8]

Since then, the emergence of new high-cost drugs for treating bowel cancer, along with an increase in incidence in line with population ageing, has led to substantial growth in bowel cancer treatment costs in Australia. A modelling study on health expenditure on treatment for bowel cancer has estimated the overall costs to reach $2 billion by 2040 in the absence of a population screening program,^[9] which is double the cost estimate of $1 billion by 2013.^[10] This is expected to make bowel cancer the nation’s most expensive cancer to treat.

The introduction of the National Bowel Cancer Screening Program using a phased roll out from 2008 to 2012, at a cost of around $30 million per annum,^[11] has also increased overall bowel cancer expenditure in Australia. However, the increase in expenditure is predicted to be transient until 2028. From 2029, annual expenditure is expected to decrease by $1.7 billion between 2030- 2040 if participation rates remain at 40%.^[9] Further reductions are expected if higher participation rates are achieved ($2.0 billion at 50% participation and $2.1 billion at 60% participation).^[9]