Ellen Phiddian
Cosmos science journalist
Cancer is becoming less deadly in Australia, according to the most recent biennial large-scale analysis.
The Australian Institute for Health and Welfare (AIHW) has released its biennial report on cancer in Australia, synthesising data on Australian cancers up to the year 2017.
It finds that survival rates from cancer are continuing to improve, as they have done since the 1980s, and that the number of cancer diagnoses per 100,000 people has continued to fall from its peak in 2008.
Nevertheless, the report also predicts that in 2021 alone, roughly 150,000 Australians will be diagnosed with some form of cancer and 49,000 will die. The authors also estimate that, due to our ageing and growing population, there is likely to be 185,000 cancer diagnoses per year in Australia by 2031.
“The estimates for 2021 presented in the report are based on actual data up to the end of 2017. They don’t take into account potential health service disruptions due to COVID-19, but are still useful for identifying trends in cancer cases in Australia,” says AIHW spokesperson Justin Harvey.
Cancer diagnosis peaked at 508 cases per 100,000 Australians in 2008, and is now at 486 cases per 100,000 (excluding non-melanoma skin cancers, which are more common and typically much less serious than other forms of cancer). This decline is mostly due to improvements in prostate cancer diagnosis, with other forms of cancer diagnosis remaining stable.
The death rate from cancer, however, has continued to fall, with overall five-year mortality rates dropping from 49% in 1988-1992, to 30% in 2013-2017. According to the report, there is a number of reasons for this – including a population-wide decrease in smoking, improved early detection methods, and the availability of better treatments.
Read more: Chronic disease mapped across Australia
“Changes in survival rates over time varied by cancer type, with the largest survival improvements seen in prostate cancer, kidney cancer, multiple myeloma, non-Hodgkin lymphoma and tongue cancer,” says Harvey.
“While many cancers have high rates of survival, people diagnosed with cancers such as pancreatic cancer, lung cancer and mesothelioma have a less than one-in-five chance, on average, of surviving at least five years after diagnosis.”
Rare and less common cancers (including cancer of the stomach, liver, bladder and brain) are also deadlier, accounting for 30% of diagnoses in 2017 but 42% of deaths.
Cancer is still more deadly for men than it is for women, but this is beginning to equalise, with the male mortality rate falling faster than the female mortality rate.
While it’s good news that the death and diagnosis rates are falling, the AIHW report stresses that there is still much work to be done on cancer prevention and treatment. Just under half (42%) of the cancer burden can be attributed to behavioural factors like smoking, and the cancer burden does not fall evenly among Australians.
Indigenous Australians are 14% more likely to be diagnosed with cancer and 20% less likely to survive at least five years after diagnosis. People living in the regions are more likely to be diagnosed with cancer, with increasing remoteness tied to decreasing survival chances. And people in the most socioeconomically disadvantaged areas are 5% less likely to be diagnosed with cancer than those in areas with the highest socioeconomic status, but 40% more likely to die from it.
Read more: Breast cancer focus
The AIHW also stresses that COVID-19 and its associated effects may have undone some of the progress of the past decades.
“After increasing by an average of 1% per year over the previous 20 years, the rate of cancer-related hospitalisations decreased by 1% between 2018-19 and 2019-20 – noting that COVID-19 restrictions were in place only during the last quarter of 2019-20,” says Harvey.
“COVID-19 restrictions also appear to have affected uptake of breast ultrasound, mammography, breast MRI and colonoscopy.”
The report doesn’t cover population-wide data for 2020 and 2021, and this won’t be collated and examined in full for another few years.
“The full impact of the COVID-19 pandemic on cancer diagnosis and treatment will not be known for some time,” says Harvey.