Cancer of unknown primary site in Australia statistics
The following material has been sourced from the Australian Institute of Health and Welfare
Cancer of unknown primary site incorporates ICD-10 cancer codes: Incidence C80 (Malignant neoplasm without specification of site); mortality C77–C80 (C77: Secondary and unspecified malignant neoplasm of lymph nodes, C78: Secondary malignant neoplasm of respiratory and digestive organs, C79: Secondary malignant neoplasm of other and unspecified sites; C80: Malignant neoplasm without specification of site), C97 (Malignant neoplasms of independent primary multiple sites).
Estimated number of new cases of cancer of unknown primary site diagnosed in 2020
2,317 = 
1,289 males + 
1,028 females
Estimated % of all new cancer cases diagnosed in 2020
1.6%
Estimated number of deaths from cancer of unknown primary site in 2020
2,358 = 
1,255 males + 1,103 females
Estimated % of all deaths from cancer in 2020
4.9%
Chance of surviving at least 5 years (2012–2016)
13%
People living with cancer of unknown primary site at the end of 2015 (diagnosed in the 5 year period 2011 to 2015)
2,812
New cases
In 2016, there were 2,482 new cases of cancer of unknown primary site diagnosed in Australia (1,357 males and 1,126 females). In 2020, it is estimated that 2,317 new cases of cancer of unknown primary site will be diagnosed in Australia (1,289 males and 1,028 females).
Figure 1. Estimated most common cancers diagnosed, 2020
Notes
- Data sourced from AIHW Cancer Data in Australia 2020 web report and supplementary data tables
- More information about incidence rates for the most common cancers diagnosed can be found on the NCCI website in the ‘Cancer incidence’ section (https://ncci.canceraustralia.gov.au/diagnosis/cancer-incidence/cancer-incidence)
In 2016, the age-standardised incidence rate was 8.6 cases per 100,000 persons (11 for males and 6.8 for females). In 2020, it is estimated that the age-standardised incidence rate will decrease slightly to 7.1 cases per 100,000 persons (8.8 for males and 5.6 for females). The incidence rate for cancer of unknown primary site is expected to increase with age.
Figure 2. Age-standardised incidence rates for cancer of unknown primary site, 1982 to 2016, by sex
Notes
- Data sourced from AIHW Cancer Data in Australia 2020 web report and supplementary data tables
- More information about incidence rates for cancer of unknown primary site over time, by age, sex, Indigenous status, remoteness, and socioeconomic status (SES) can be found on the NCCI website in the ‘Cancer incidence’ section (https://ncci.canceraustralia.gov.au/diagnosis/cancer-incidence/cancer-incidence)
The number of new cases of cancer of unknown primary site diagnosed increased from 2,141 (1,119 males and 1,022 females) in 1982 to 2,482 in 2016. Over the same period, the age-standardised incidence rate decreased from 18 cases per 100,000 persons (21 for males and 15 for females) in 1982 to 8.6 cases per 100,000 in 2016.
Deaths
In 2016, cancer of unknown primary site was the sixth most common cause of cancer death in Australia. It is estimated that it will remain the sixth most common cause of death from cancer in 2019.
In 2016, there were 2,554 deaths from cancer of unknown primary site in Australia (1,373 males and 1,181 females). In 2019, it is estimated that this will decrease to 2,431 deaths (1,258 males and 1,173 females). In 2019, it is estimated that the risk of an individual dying from cancer of unknown primary site by their 85th birthday will be 1 in 108 (1 in 88 males and 1 in 135 females).
Figure 3. Estimated most common causes of cancer death, 2020
Notes
- Data sourced from AIHW Cancer Data in Australia 2020 web report and supplementary data tables
- More information about mortality rates for the most common causes of cancer death can be found on the NCCI website in the ‘Cancer mortality’ section (https://ncci.canceraustralia.gov.au/outcomes/cancer-mortality/cancer-mortality)
In 2018, the age-standardised mortality rate was 8.8 deaths per 100,000 persons (11 for males and 7 for females). In 2020, it is estimated that the age-standardised mortality rate will be 7.2 deaths per 100,000 persons (8.5 for males and 5.9 for females). The mortality rate for cancer of unknown primary site is expected to increase with age.
Figure 4. Age-standardised mortality rates for cancer of unknown primary site, 1982 to 2018, by sex
Notes
- Data sourced from AIHW Cancer Data in Australia 2020 web report and supplementary data tables
- More information about mortality rates for cancer of unknown primary site over time, by age, sex, Indigenous status, remoteness, and socioeconomic status (SES) can be found on the NCCI website in the ‘Cancer mortality’ section (https://ncci.canceraustralia.gov.au/outcomes/cancer-mortality/cancer-mortality)
The number of deaths from cancer of unknown primary site increased from 1,202 (609 males and 593 females) in 1982 to 2,734 in 2018. Over the same period, the age-standardised mortality rate decreased slightly from 10 deaths per 100,000 persons (12 for males and 8.9 for females) in 1982 to 8.8 deaths per 100,000 in 2018.
Survival
In 2012–2016, individuals diagnosed with cancer of unknown primary site had a 13% chance (17% for males and 9.6% for females) of surviving for five years compared to their counterparts in the general Australian population. Between 1987–1991 and 2012–2016, five-year relative survival for cancer of unknown primary site improved from 6.4% to 13%.
Figure 5. 5-year relative survival for cancer of unknown primary site, 1987–1991 to 2012–2016, by sex
Notes
- Data sourced from AIHW Cancer Data in Australia 2020 web report and supplementary data tables
- More information about 5-year relative survival rates for cancer of unknown primary site over time, by age, sex, Indigenous status, remoteness, and socioeconomic status (SES) can be found on the NCCI website in the ‘Relative survival rate’ section (https://ncci.canceraustralia.gov.au/outcomes/relative-survival-rate/5-year-relative-survival)
Prevalence
At the end of 2015, there were 983 people living who had been diagnosed with cancer of unknown primary site that year, 2,812 people living who had been diagnosed with cancer of unknown primary site in the previous 5 years (from 2011 to 2015) and 6,949 people living who had been diagnosed with cancer of unknown primary site in the previous 34 years (from 1982 to 2015).
For more information on cancer data, see the NCCI website
The National Cancer Control Indicators (NCCI) are a set of indicators across the continuum of cancer care, from Prevention and Screening through to Diagnosis, Treatment, Psychosocial care, Research and Outcomes. The NCCI website allows users to see visual representations of data on each indicator through interactive charts.
