Melanoma: deaths by LHD and year

NSW Central Cancer Registry

The NSW Central Cancer Registry (CCR) was established by the NSW Ministry of Health in 1971 under the NSW Public Health Act. It was administered by the Cancer Council NSW, under contract, from 1986 until June 2004. The Registry has been managed by the Cancer Institute NSW since June 2004.

Cancer incidence and cancer deaths datasets

Notification of newly diagnosed cases of, and deaths due to, malignant neoplasm is a statutory requirement for public and private hospitals, pathology laboratories, day procedure centres, departments of radiation oncology, outpatient departments and nursing homes. Death certificates are provided by the NSW Registry of Births, Deaths and Marriages. Data collected on notification forms include identifying and demographic information, brief medical details describing the cancer and a record of at least one episode of care from each notifier. These data are supplemented by pathology reports and death certificates. For breast cancer and cutaneous melanoma additional prognostic factors are coded from pathology reports and in situ lesions are registered. Notification has traditionally been via a printed notification form, although in recent years electronic notification by hospitals (but not pathology laboratories) has been introduced.

Multiple primary cancers

Multiple primary cancers in the same person are counted according to rules set out by the International Association of Cancer Registries. The term 'cases' refers to ether newly diagnosed cancers or deaths. Cases are the basis for reporting in this report and in the reports by the NSW Cancer Institute. Only cancer prevalence is reported as a number of individuals living with cancer as well as a number of cases of cancers in living persons in this report. Deaths of individuals from cancer refer to a one primary cancer listed as the cause of death (an underlying cause of death).

The span of ICD-10-AM codes

The cancers for which notification is required fall within the following ICD-10-AM codes: C00-C76 and C80-C96. Codes C77-C79 refer to secondary malignant neoplasms from primary sites which have been already a subject of notification. Notification of basal and squamous cell carcinoma of the skin is not required (C44 topography code applies where morphology code is between M805-M811). Squamous cell carcionomas of the lip, vulva, penis, scrotum and anus are registered when notified but data are not routinely reported by the CCR.

ICD-9, ICD-10 and ICD-O classifications

Incident cases and deaths registered before July 1999 were classified according to the 9th revision of the International Classification of Diseases (ICD-9, World Health Organization, 1977). Cases registered from July 1999 onwards have been classified according to the 3rd edition of the International Classification of Diseases for Oncology (ICD-O-3, World Health Organization, 1990). ICD-O-3 codes were mapped to ICD-10-AM codes by the Registry.

Classifications and datasets  used in this report

This report uses ICD-9 and ICD-10 topography codes, except in two indicators. Leading cancers by type were analysed using ICD-O-3 morphology codes and mesothelioma trend uses ICD-O-3 and its predecessors (that is, values from the 'topotab' variable, Cancer Library, SAPHaRI). Morphology coding was used in these two analyses to ensure that counts of cancers in a group Ill-defined and unknown primary site and Mesothelioma were the same as those reported by the Cancer Institute NSW. Detailed discussion of coding decisions can be found in publications by the Cancer Institute NSW.

For this report, cancer incidence data were supplied by the NSW Central Cancer Registry and accessed via SAPHaRI. The cancer deaths data presented here are from the Australian Bureau of Statistics mortality collection. The ABS death data were used to maintain consistency with other chapters of the report. The CCR figures for death from cancer differ slightly from the ABS cancer data, because the CCR data are verified against cases’ histopathological reports while the ABS data are sourced only from the information on death certificates.

Local Health Districts (LHDs) are health administrative areas constituted under Section 17 of the NSW Health Services Act, 1997 which became effective from January 2011 and were initially called Local Health Networks.

There are 15 geographically-based LHDs (8 covering the Sydney metropolitan region and 7 rural and regional NSW) and two specialist networks focussing on Children's and Paediatric Services and Forensic Mental Health. A third network operates across the public health services provided by three Sydney facilities operated by St Vincent's Health: these include St Vincent's Hospital and the Sacred Heart Hospice at Darlinghurst and St Joseph’s at Auburn.

LHDs replaced the former Area Health Services and have their own budgets, management and accountabilities. Geographically-based LHDs are overseen by Governing Boards. Please refer to the NSW Health website for a list of Local Health Districts and the membership of Boards.  

Local Health Districts are:

Metropolitan NSW: Central Coast, Illawarra Shoalhaven, Nepean Blue Mountains, Northern Sydney, South Eastern Sydney, South Western Sydney, Sydney, Western Sydney.

Rural & regional NSW:  Far West, Hunter New England, Mid North Coast, Murrumbidgee, Northern NSW, Southern NSW, Western NSW

Smoothing of estimates for rare conditions analysed by Local Health District in this report

The term ‘small area’ refers to a small geographical area and a small population. Data from a small area are characterised by considerable variability. Smoothing is a general term for statistical methods used to reduce the random variability of data. Examples include rounding, moving averages, extending the period of time in which cases are counted or increasing the size of the areas. In addition, Bayesian statistical smoothing can be used to adjust raw estimates in small areas by taking into account information from adjacent areas (local or spatial variability) and from the whole state (global or non-spatial variability).

In this report, extending the period of time, in which cases in the Local Health Districts are counted, was the most frequently used smoothing technique. Results for some Local Health Districts were completely suppressed in few indicators due to very low numbers and privacy concerns.  Refer to Notes under the graphs or Methods tabs for confirmation of suppression and the smoothing technique used.

References

NSW Health. Home page. Last updated 1 July 2011. Available at http://www.health.nsw.gov.au/services/pages/default.aspx

Cancer registration in Australia and in NSW

Cancer registration is a fundamental tool of cancer monitoring. Australian states and territories are required by legislation to maintain a cancer registry. This requirement has resulted in cancer being the only major disease for which almost complete coverage of incidence data (that is, data on new cases) is available (AIHW Cat. no. AUS 122 2010). In NSW, notification of cancer is a statutory requirement for all public and private hospitals, and pathology laboratories (Parliamentary Counsel's Office ).

The NSW Central Cancer Registry has been operating since 1972 and is based at the Cancer Institute NSW. The Registry collects and reports annually on cancer cases and deaths in NSW on behalf of the NSW Ministry of Health. The registry reports on notifiable cases of invasive cancer. Basal and squamous cell carcinoma of skin (non-melanocytic skin cancers), the most common types of cancer, are not notifiable and are not included in the Registry reports.

Source of incidence data and classifications used in this report

Cancer incidence data were supplied by the NSW Central Cancer Registry and accessed via SAPHaRI.

This report uses ICD-9 and ICD-10 topography codes, except in two indicators. Leading cancers by type were analysed using ICD-O-3 morphology codes and mesothelioma trend uses ICD-O-3 and its predecessors (that is, values from the 'topotab' variable, Cancer Library, SAPHaRI). Morphology coding was used in these two analyses to ensure that counts of cancers in a group Ill-defined and unknown primary site and Mesothelioma were the same as those reported by the Cancer Institute NSW. Detailed discussion of coding decisions can be found in publications by the Cancer Institute NSW.

Source of death from cancer data in this report

Deaths data presented here are from the Australian Bureau of Statistics (ABS) mortality collection. The ABS deaths data is used here to maintain consistency with other chapters, however, the Cancer Institute NSW's (CI) cancer death figures may differ slightly as the CI case data are verified against histopathology reports while the ABS data are sourced only from death certificates.

Projections of cancer incidence and mortality

Projections of cancer incidence and mortality provide a valuable indication of the current and near future expected burden on the NSW health system, which can be used to better inform planning and decision-making, and assist in the efficient allocation of resources to meet the short-term needs of the health system for the prevention, detection, and treatment of cancer.

Cancer incidence and mortality projections, however, are subject to uncertainty. They are influenced by a large number of risk factors that are difficult or impossible to measure, or are yet to be discovered. The projections contained in this report should be interpreted as best estimates of future incidence and mortality based on historical trends. In particular, the introduction of new population screening programs, such as the National Bowel Screening Program, developments in treatment, or discovery of new cancer-specific risk factors may cause future incidence and mortality to differ substantially from the estimates provided in this report (Aitken R et al. 2008). Projections further into the future should be treated with increased caution due to increasing uncertainty.

Survival after diagnosis of cancer

The '5-year survival rate' is the proportion of cancer patients who have not died from their cancer five years after being diagnosed with cancer. It is an important indicator of the burden of cancer, and in particular, the variation in prognosis that exists between different cancer types (Tracey et al. 2007).

Interdependence between incidence, mortality and survival from cancer

Cancers that are the most common cause of cancer death are usually also the most commonly diagnosed cancers, however not in the same order.  For example, prostate cancer, which is ranked first among new cancer cases (32.2% of new cases in males), is ranked third among causes of cancer death (13.0%). This is because the survival after diagnosis is very high with 88% of men surviving at least 5 years after diagnosis and majority of prostate cancer sufferers dying of other causes.

Monitoring success of screening programs

The aim of screening for cancer is to reduce mortality and disability from the disease. Reduced mortality rates, and not 5-year survival, are the appropriate measure of success of screening, because short-term survival may be extended purely as a consequence of the cancer being diagnosed earlier in the course of the disease, for example before symptoms are apparent, but without any real benefit to the sufferer’s life span.

Improvements in long term survival, after introducing screening for a particular cancer, are evident through the increase in death rates from other causes among people once diagnosed with that particular cancer.

References

Aitken R, Morrell S, Barraclough H, Baker D, Clements M, Jelfs P, Bishop J. Cancer incidence and mortality projections in New South Wales, 2007 to 2011. Sydney: 2008. Available at http://www.cancerinstitute.org.au/cancer_inst/publications/pdfs/em-2007-04_cancer-incidence-and-mortality-projections-2007-2011.pdf

Australian Institute of Health and Welfare. Australia’s health 2010. Australia’s health series no. 12. Cat. no. AUS 122. Canberra: AIHW, 2010. Available at http://www.aihw.gov.au/publication-detail/?id=6442468376

New South Wales Government. Public Health Act 1991 and Public Health Act 2010. Parliamentary Counsel's Office. Available at http://www.legislation.nsw.gov.au

Tracey E, Barraclough H, Chen W, Baker D, Roder D, Jelfs P, Bishop J. Survival from Cancer in NSW: 1980 to 2003. Sydney: Cancer Institute NSW, 2007. Available at http://www.cancerinstitute.org.au/cancer_inst/publications/pdfs/em-2007-01_survival_from_cancer_in_NSW.pdf

Death (or mortality) statistics

Death or mortality statistics are based on the information contained in death certificates. Most administrative jurisdictions in all nations produce tables of mortality statistics. They are published at regular intervals and usually show numbers and rates of deaths by sex, age and other variables (Last 2001).

Death rates from all causes and several specific causes, such as cardiovascular causes, cancer, motor vehicle accidents, together with life expectancy, infant mortality, self-reported health status and disability adjusted life years are among the most useful indicators of the status of health in a community (OECD 2010)(WHO 2010).

Death rates definition

A death rate is an estimate of the proportion of population that dies during a specified period. It is usually expressed as a number of deaths per 10ⁿ population (person-years) (Last 2001). Age and sex standardisation is performed to make rates comparable between different sub-populations, for example between different States and Territories or Local Health Districts and over time to take into account changes in the age and sex structure of populations. Death rates in this report are standardised to the Australian population 2001 and expressed as a number of deaths per 100,000 population.

Death certification in Australia

In order to complete a death registration in Australia, the death must be certified by either a doctor using the Medical Certificate of Cause of Death, or by a coroner. Natural causes are predominantly certified by doctors, whereas External and Unknown causes or unaccompanied deaths are usually certified by a coroner. Approximately 85-90% of deaths each year are certified by a doctor and the remainder is reported to a Coroner (ABS 3302.0 2010).

Death registration in Australia

The registration of deaths is the responsibility of the eight individual state and territory Registrars of Births, Deaths and Marriages. As part of the registration process, information about the cause of death is supplied by the medical practitioner certifying the death or by a coroner. Other information about the deceased is supplied by a relative or other person acquainted with the deceased, or by an official of the institution where the death occurred. The information is subsequently provided to the Australian Bureau of Statistics by individual Registrars for coding and compilation into aggregate statistics. In addition, the ABS supplements these data with information from the National Coroners Information System (NCIS) (ABS 3302.0 2010).

Death certificate

The Medical Certificate of Cause of Death includes cause of death, personal identifying data (including in Australia whether the deceased person was of Aboriginal or Torres Strait Islander origin) and whether the deceased had been medically attended before death.

The part of the death certificate that refers to the cause of death follows the international form of medical certificate of death, published by the WHO in the International Statistical Classification of Diseases and Related Health Problems, 10 revision (ICD-10) (WHO 1992).  Immediate causes of death, conditions giving rise to the immediate cause of death, the underlying cause of death and causes contributing to death are recorded (Last 2001).

 Underlying cause of death

The underlying cause of death is the cause recorded in official publications of cause specific mortality. The underlying cause of death is (1) the disease or injury that initiated the train of events leading to death or (2) the circumstances of the accident or violence that produced the fatal injury.

All causes of death listed on a death certificate other than the underlying cause are called associated causes of death (ABS 3302.0 2010).

The term ‘contributing causes of death’ is also used in relation to death certificates. This terms refers to ‘other significant conditions contributing to the death but not related to disease of condition causing it’ on the death certificate itself (Part II of the certificate, ‘below the line’ causes of death) and consequently to a subset of associated causes according to the ABS nomenclature. The ABS analysis of multiple causes of death is based mostly on the contributing causes of death (ABS 3302.0 2010) (ABS 3319.0.55.001 2003). The Secure Analytics for Population Health Research and Intelligence (SAPHaRI), the NSW Ministry of Health data warehouse, refers to all associated causes as contributing causes and the SAPHaRI datasets containing data on underlying and other causes of death contain the ‘cc’ abbreviation in their names, for example deaths.nswres97_07cc.

The causes of death should be distinguished from mode of dying (that is heart failure, respiratory failure, asthenia) which is not recorded (Last 2001). 

Coroner certified deaths

In Australia, approximately 10-15% of deaths each year are certified by a coroner. Although there is variation across jurisdictions in Australia in what constitutes a death that is reportable to a coroner, they are generally reported in circumstances such as: where the person died unexpectedly and the cause of death is unknown; where the person died in a violent or unnatural manner; where the person died during or as a result of an anaesthetic; where the person was 'held in care' or in custody immediately before they died; and where the identity of the person who has died is unknown (ABS 3302.0 2010).

Coroner cases remain 'open' while investigations of the cause of death are undertaken, and cases are closed when coronial investigations are complete. Following completion, causes of death information is passed to the Registrar of Births, Deaths and Marriages, as well as to the National Coroners Information System (NCIS). Coronial cases and the process of certification have a considerable impact on enumeration of some causes of death, such as suicides. Further discussion can be found in the topic Suicide in this report and in the ABS publications on Causes of death 3303.0 (Technical note 2 and 3) (ABS 3302.0 2010).

Coding of causes of death data for statistical purposes

The ABS coding process classifies the text describing causes of death on the death certificate and from Coroners’ files into codes for statistical purposes. The data are processed using specialised software. The coding system used is the International Statistical Classification of Diseases and Related Health Problems (ICD) published by the World Health Organisation (WHO).

The ICD is periodically revised, these revisions have been co-ordinated by the WHO since the Sixth revision of the ICD in 1948. The Ninth revision (ICD-9) came into force in Australia on 1 January 1979. There are no data coded to ICD revisions earlier than the ICD-9 revision in this report.  The current tenth revision of the ICD (ICD-10) came into use in Australia on 1 January 1999. The ABS coded death data to ICD-10 prospectively as well as back coded death data from 1997 and 1998. Consequently, in this report death data from 1997 onwards are described using exclusively ICD-10 codes.

Causes of death in NSW

The Australian Bureau of Statistics publishes two publications every year: Deaths, Australia (Catalogue Number 3302.0) in November, eleven months after the end of the concerned year and Causes of death, Australia (Catalogue Number 3303.0), in March, fifteen months after the end of the concerned year. 

The State and Territory Health Departments or Ministries obtain death datasets relevant to their jurisdictions from the ABS and perform their own detailed analysis. Delays, due to privacy issues, in releasing cause of death datasets to State and Territories by the ABS are responsible for the delay in publication of detailed analyses of NSW causes of death by the NSW Health Department in this publication.  For example, the latest NSW death data analysis in this publication still concerned 2007 in the second quarter of 2013, which was sixty four months after the end of the concerned year. 

Difference between figures published by the ABS and the NSW Ministry of Health

Number of deaths by the year of registration and by the year of occurrence.

The difference between the ABS published figure (5.9 per 1,000 in NSW in 2007) and the NSW Ministry of Health figure for the same year (5.7 per 1,000 in NSW in 2007) mainly stems from the fact that the ABS figures are calculated from the number of deaths by the year of registration of death while the NSW figures concern the actual year of death.

There is usually an interval between the occurrence and registration of a death. Deaths which occur in November and December are likely to be registered in the following year. Out of all deaths of NSW registered in 2009, 4% occurred in 2008 (ABS 3302.0 2010). Full registration of deaths reportable to a coroner is often more difficult to achieve (see Methods tab associated with the topic of Suicide for more discussion of coronial deaths).

Delay in making the data available to agencies

Since 2007, the ABS has been publishing the number of deaths by the year of occurrence (by sex, age and state or territory) in an easily accessible format, but the rates are not calculated. Also from 2007, the ABS has been publishing revised numbers of death for all the years in the series (ABS 3302.0 2010). Because the ABS publishes death data well before the same data are made available to the state agencies, the numbers published by the NSW Ministry of Health and by the ABS seldom match exactly at the same time. For example, the ABS published in 2008 that 44,986 NSW residents died in 2007 (ABS 3302.0 2008) and in 2010 that 47,314 NSW residents died in 2007 (ABS 3302.0 2010), which was an increase of over 5%.  

Imputation of deaths

A further discrepancy in reported figures from these two sources is due to the fact that, at the time when the NSW Ministry of  Health obtains the death data file from the ABS, the last year of death is ‘imputed’ for this report. This means that an estimate of the number of deaths occurring in the report year but registered in the next year is made for each cause of death and this number is added in to the statistics and calculations for the report year. This is particularly important for deaths which result in a coronial inquest, where there can be long delays in registering a cause of death. In general, an imputed number is closer to the actual number of deaths however it is not the same as the actual number when it becomes known. All deaths figures are updated historically (eg in trends) in this report when new data beomes available.

Different projected Estimated Residential Populations

For the calculation of rates, the NSW Ministry of Health uses population projection data estimates based on the NSW Health Population Projection Series 1, 2009, prepared by the Statewide Services Development Branch of the NSW Ministry of Health in collaboration with the NSW Department of Planning. The estimated residential populations which are not projected are the same as those published by the ABS and are currently based on the 2006 Census. See Methods associated with indicators in topics Demography (or Population) for further discussion of population estimates.

References

Australian Bureau of Statistics. Deaths, Australia 2009. 3302.0. Canberra: ABS, 2010. Available at http://www.abs.gov.au/AUSSTATS/abs@.nsf/DetailsPage/3302.02009?OpenDocument

Australian Bureau of Statistics. Multiple causes of death analysis, 1997-2001. 3319.0.55.001. Canberra: ABS, 2003. Available at http://www.abs.gov.au/AUSSTATS/abs@.nsf/Lookup/3319.0.55.001Main Features11997-2001?OpenDocument

Last JM (eds). A dictionary of epidemiology. Fourth edition. New York: Oxford University Press. Inc, 2001.

Organisation for Economic Cooperation and Development. OECD Health data 2010 October. OECD. (Last updated 21 October 2010. Cited on November/26, 2010). Available at URL password protected

World Health Organisation. World health statistics 2010. Geneva: WHO, 2010. Available at http://www.who.int/whosis/whostat/en/index.html

World Health Organization. International Statistical Classification of Diseases and Related Health Problems, 10th revision (ICD-10). Geneva: WHO, 1992.