Overview live

Cancer is the term given to a number of related diseases [33599]. It is a genetic disease, arising from changes to the genes (DNA) that control the way cells behave. In all cancers, some of the cells of the body divide in an uncontrolled manner (cells normally grow and divide as the body needs them). When cancer cells spread into surrounding tissues, or to different parts of the body (metastasise) they are known as malignant [24363]. Cancer can start almost anywhere in the body [33599].

There is limited evidence or data available on cancer to inform initiatives to improve outcomes for Aboriginal and Torres Strait Islander people [30100]. Inconsistent Indigenous identification in cancer notifications in several jurisdictions is an issue [25330]. The National Aboriginal and Torres Strait Islander Cancer Framework highlights the need for improved Indigenous identification, including on pathology requests and reports [30100]. It also expresses a need for routine national data collection, access and linkage to allow national monitoring and reporting, and inform strategies to improve cancer care and outcomes.

Extent of cancer among Aboriginal and Torres Strait Islander people

Incidence

For 2009-2013, there were 6,397 new cases of cancer diagnosed in Aboriginal and Torres Strait Islander people living in NSW, Vic, Qld, WA and the NT (an average of 1,279 new cases per year) [31288]. Aboriginal and Torres Strait Islander people were 1.1 times more likely to be diagnosed with cancer as non-Indigenous people. After age-adjustment, the cancer incidence rate for all cancers combined was higher for Aboriginal and Torres Strait Islander people than for non-Indigenous people (501 per 100,000 and 439 per 100,000 respectively) [31288]. Age-adjusted cancer incidence rates were higher for Aboriginal and Torres Strait Islander people than non-Indigenous people for: liver cancer (rate ratio: 2.4); lung cancer (rate ratio: 2.1); cancers of unknown primary site (rate ratio: 2.1); head and neck cancer (rate ratio 1.9); cancer of the uterus (rate ratio: 1.8), and pancreatic cancer (rate ratio 1.6) (Table 1). Cancer incidence rates were the same or lower for: colorectal (bowel) cancer (rate ratio: 1.0); breast cancer (rate ratio: 0.9); non-Hodgkin lymphoma (rate ratio: 0.9); and prostate cancer (rate ratio: 0.7).

Table1. Age-standardised incidence rates for the 10 most common cancers, by Indigenous status, and Indigenous:non-Indigenous rate ratios, NSW, Qld, Vic, WA and the NT, 2009-2013

Primary site	Aboriginal and Torres Strait Islander age-standardised rates	Non-Indigenous age-standardised rates	Rate ratio
Lung	85	41	2.1
Breast (females)	99	112	0.9
Colorectal (bowel)	53	56	1.0
Prostate (males)	108	151	0.7
Head and neck	28	15	1.9
Uterus (females)	30	17	1.8
Liver	16	6.4	2.4
Unknown primary site	19	9.1	2.1
Pancreatic cancer	17	11	1.6
non-Hodgkin lymphoma	15	17	0.9
All cancers	501	439	1.1

Notes:     1   Rates per 100,000 population, age-standardised to the Australian population at 30 June 2001.

2   Cancers are ordered by numbers among Aboriginal and Torres Strait Islander people (not shown in table).

3   Rate ratio is the Aboriginal and Torres Strait Islander rate divided by the non-Indigenous rate.

4   Due to the incomplete identification of Aboriginal and Torres Strait Islander status, these figures probably underestimate the true difference between Aboriginal and Torres Strait Islander and non-Indigenous rates.

5   Rounding may result in inconsistencies in calculated ratios.

Source: AIHW, 2017 [31288]

Detailed information[1] is available for the incidence of cervical and breast cancers for Aboriginal and Torres Strait Islander females. For 2009-2013, after age-adjustment, the rate for cervical cancer for Aboriginal and Torres Strait Islander females aged 20-69 living in NSW, Vic, Qld, WA and NT was 2.2 times higher than for non-Indigenous females of the same age (19 per 100,000 and 8.5 per 100,000 respectively) [34826]. For 2009-2013, the age-adjusted rates for breast cancer were lower for Aboriginal and Torres Strait Islander women compared with non-Indigenous females aged 50-74 living in NSW, Vic, Qld, WA and NT (251 per 100,000 and 285 per 100,000 respectively) [35586].

For 2009-2013, detailed information for cancer incidence is available for Aboriginal and Torres Strait Islander males and females living in NSW, Vic, Qld, WA and the NT. For all cancers combined, the number of new cases were higher for females (3,300 new cases) than for males (3,097 new cases) [31288]. After age-adjustment, the rates for both Aboriginal and Torres Strait Islander males and females were higher than those for non-Indigenous males and females; males: 561 per 100,000 and 520 per 100,000 respectively, and females: 460 per 100,000 and 371 per 100,000 respectively.

Survival
Information on survival from cancer for Aboriginal and Torres Strait Islander people is based on crude survival rates (observed survival) and is provided for states and territories where the data are considered of sufficient completeness for reporting [31288]. Survival rates indicate that of the Aboriginal and Torres Strait Islander people living in NSW, Vic, Qld, WA, and the NT who were diagnosed with cancer between 2007 and 2014, 50% had a chance of surviving five years after diagnosis. This compared with a relative survival rate of 65% for non-Indigenous people. The five year relative survival rates for Aboriginal and Torres Strait Islander males and females were considerably lower compared with non-Indigenous males and females (males: 46% compared with 64%, and females: 54% compared with 67%, respectively). The five-year survival for all cancers combined was highest for Aboriginal and Torres Strait Islander people 0–14 years and for non-Indigenous people 15–24 years and decreased with age for both populations (Table 2).

Table 2. Five year relative survival for all cancers combined by Indigenous status and age, NSW, Vic, Qld, WA and the NT, 2007–2014

Age group (years)	Aboriginal and Torres Strait Islander relative survival (%)	Non-Indigenous relative survival (%)
0–14	82	84
15–24	78	87
25–44	66	84
45–64	50	74
65+	40	56

Source: AIHW, 2018 [31288]

 

Hospitalisation

In 2016–17, there were 7,931 hospital separations for neoplasms^[2] for Aboriginal and Torres Strait Islander people in Australia, representing 3.0% of all separations (excluding dialysis) among Aboriginal and Torres Strait Islander people (Derived from [34922]). After age-adjustment, Aboriginal and Torres Strait Islander people were less likely to be hospitalised for neoplasms than non-Indigenous people (19 per 1,000 and 25 per 1,000 respectively).

For specific cancers where details are available in 2014–15, the age-standardised hospitalisation rates for lung and cervical cancers for Aboriginal and Torres Strait Islander people were 2.0 and 3.0 times higher respectively than for non-Indigenous people [32347]. Hospitalisation rates for lung cancer were slightly higher for Aboriginal and Torres Strait Islander males than females (1.4 per 1,000 and 1.3 per 1,000 respectively), and also higher for non-Indigenous males than females (0.8 per 1,000 and 0.5 per 1,000 respectively). Mortality

In 2017, cancers of the trachea, bronchus and lung  combined were the fourth leading cause of death for Aboriginal and Torres Strait Islander people (184 deaths: 101 males and 83 females) living in NSW, Qld, WA, SA and the NT, with the overall age-adjusted death rate 2.2 times higher than for non-Indigenous people [35563].

For 2011-2015 cancer was responsible for the deaths of 2,754 Aboriginal and Torres Strait Islander people living in NSW, Qld, WA, SA and the NT (an average of 551 deaths per year) [31288]. Lung cancer was the leading cause of cancer death for Aboriginal and Torres Strait Islander people and non-Indigenous people.

After age-adjustment, the mortality rate for all cancers combined for Aboriginal and Torres Strait Islander people was 1.4 times higher than for non-Indigenous people (230 per 100,000 and 166 deaths per 100,000 respectively). The mortality rates were higher for Aboriginal and Torres Strait Islander people than non-Indigenous people for cancers of the head and neck (rate ratio: 3.4); liver cancer (rate ratio: 2.4); cancer of the oesophagus (rate ratio: 1.9); cancer of the unknown primary site (rate ratio: 1.9); cancer of the lung (rate ratio: 1.8); and stomach (rate ratio: 1.8); pancreas (rate ratio: 1.2) and breast (rate ratio: 1.2) (Table 3). Rates were lower for prostate cancer (rate ratio: 0.9 times) and bowel cancer (rate ratio: 0.9).

Table 3. Age-standardised death rates for the 10 most common cancers, by Indigenous status, and Indigenous: non-Indigenous rate ratios, NSW, Qld, WA, SA and the NT, 2011-2015

Primary cancer	Aboriginal and Torres Strait Islander age-standardised rates	Non-Indigenous age-standardised rates	Rate ratio
Lung	57	31	1.8
Liver	15	6.1	2.4
Head and neck	13	4.0	3.4
Unknown primary site	18	9.8	1.9
Breast (females)	24	20	1.2
Bowel (colorectal)	14	15	0.9
Pancreas	12	9.6	1.2
Oesophagus	8.6	4.6	1.9
Stomach	7.4	4.1	1.8
Prostate (males)	25	27	0.9
All cancers	230	166	1.4

Notes:

1   Rates per 100,000 population, age-standardised to the Australian population at 30 June 2001.

2   Cancers are ordered by numbers among Aboriginal and Torres Strait Islander people (not shown in table).

3   Rate ratio is the Aboriginal and Torres Strait Islander rate divided by the non-Indigenous rate.

4   Due to the incomplete identification of Aboriginal and Torres Strait Islander status, these figures probably underestimate the true difference between Aboriginal and Torres Strait Islander and non-Indigenous rates.

5   Rounding may result in inconsistencies in calculated ratios.

6   Rate ratios less than one indicate that non-Indigenous people experience higher rates of the disease.

Source: AIHW, 2016 [31288]

For 2011-2015, the age-standardised Aboriginal and Torres Strait Islander cancer mortality rates: non-Indigenous cancer mortality rates were 1.5 times higher for females (202 per 100,000 and 132 per 100,000 respectively) and 1.3 higher for males (269 per 100,000 and 209 per 100,000 respectively) [31288].

For 2011-2015, the age-specific cancer mortality rates were higher for Aboriginal and Torres Strait Islander people in all age-groups 20-29 years and 35-74 years to 85+, compared with non-Indigenous people [31288]. The biggest disparity in the mortality rates between the populations occurred in the 50-54 years age-group (rate ratio: 2.0). Aboriginal and Torres Strait Islander children and adolescents 0-19 years (excluding 10-14 years) had age-specific mortality rates the same or lower than those for non-Indigenous people with rate ratios ranging from 0.7(15-19 and 5-9 years) to 1.0 (0-4 years).

The patterns of Aboriginal and Torres Strait Islander cancer incidence and mortality can be partly explained by the higher level of risk factors, most notably tobacco use [26088]. High rates of smoking are the likely cause of a high incidence of cancer of the lung. High incidence rates of liver cancer are consistent with risky levels of alcohol consumption and a higher prevalence of Hepatitis B infection. Other contributing factors include:

• Aboriginal and Torres Strait Islander people being more likely to have cancers that have a poor prognosis
• being diagnosed with cancer at a later stage
• being more likely to present with co-morbidities (that may lead to poorer outcomes)
• being less likely to receive any treatment or adequate treatment [363][1254][27997].

Burden of disease

Cancer and other neoplasms[3] were responsible for 9.4% of the total burden of disease among Aboriginal and Torres Strait Islander people in 2011, comprising 17% of all fatal burden and 0.5% of all non-fatal burden [32052]. Cancer burden was almost entirely due to premature death. It was the fourth leading disease group causing burden for Aboriginal and Torres Strait Islander people (cancer was the leading disease for the total population) [33221]. Lung (24%), bowel (8%), liver (7%), breast (7%) and mouth and pharyngeal (throat) (6%) cancers contributed to over half (51%) of this cancer burden [32052].

[1] This information is from the national screening programs for cervical and breast cancer and presents data for specific age groups.

[2] Neoplasms C00-D48 also includes benign neoplasms D10-D36 ICD-10-AM.

[3] Cancer and other neoplasms include malignant neoplasms (cancer) and benign and uncertain neoplasms [32052].

[1] This information is from the national screening programs for cervical and breast cancer and presents data for specific age groups.

[2] Neoplasms C00-D48 also includes benign neoplasms D10-D36 ICD-10-AM.

[3] Cancer and other neoplasms include malignant neoplasms (cancer) and benign and uncertain neoplasms [32052].

[4]  Cancer and other neoplasms include malignant neoplasms (cancer) and benign and uncertain neoplasms [32052].