Cancer incidence and outcomes registries in an Australian context: a systematic review

BACKGROUND

Multiple cancer registries in Australia are used to track the incidence of cancer and the outcomes of their treatment. These registries can be broadly classed into a few types with an increasing number of registries comes a greater potential for collaboration and linkage. This article aims to critically review cancer registry types in Australia and evaluate the Australian Cancer registry landscape to identify these areas.

METHODS

A systematic review was performed through MEDLINE, EMBASE and Cochrane Library, updated to September 2022 using a predefined search strategy. Inclusion criteria were those that only analysed Australian and/or New Zealand based cancer registries, appraised the utility of cancer outcomes and/or incidence registries, and explored the utility of linked databases using cancer outcomes and/or incidence registries. The grey literature was searched for all operating cancer registries in Australia. Details of registry infrastructure was extracted for analysis and comparison.

RESULTS

Three thousand two hundred and sixteen articles identified from the three databases. Twelve met the inclusion criteria. Twenty-eight registries were identified using the grey literature. Strengths and weaknesses of Cancer Outcome Registries(COR) and Cancer Incidence Registries(CIR) were compared. Data linkage between registries or with other healthcare databases show great benefits in improving evidence for cancer research but are challenging to implement. Both registry types utilize differing modes of administration, influencing their accuracy and completeness.

CONCLUSION

Outcome registries provide detailed data but their weakness lies in incomplete data coverage. Incidence registries record a large dataset which contain inaccuracies. Improving coverage of quality outcome registries, and quality assurance of data in incidence registries is required to ensure collection of accurate, meaningful data. Areas for collaboration identified included establishment of defined definitions and outcomes, data linkage between registry types or with healthcare databases, and collaboration in logistical planning to improve clinical utility of cancer registries.

Opportunities and barriers for the use of Australian cancer registries as platforms for randomized clinical trials

It is well recognized that randomized controlled trials (RCTs) are a powerful tool to investigate causal relationships, and are considered the gold standard level of research evidence. However, RCTs can be expensive and time-consuming, and when they employ strict eligibility criteria, it results in an unrepresentative population and limited external validity. Recently, the registry-based randomized clinical trial (RRCT) has emerged as an alternative trial design. Utilizing registries to underpin such studies, RRCTs can have advantages including rapid recruitment, and enhanced generalizability. In Australia, legislated mandatory reporting of cancer diagnoses means that jurisdictional cancer registries are a rich source of systematically collected patient details, representing sound platforms for comprehensive data capture that can serve as a key tool for further research. We review the roles of cancer registries in Australia, discuss important considerations relevant to the design of RRCTs, and outline the opportunities provided by cancer registries to strengthen cancer research.

Design and establishment of a cancer registry: a literature review

BACKGROUND

Establishment of a cancer registry is a complex process that requires substantial resources and careful planning. There are numerous resources available to provide guidance for this, which include guidelines and frameworks of varying quality. It is the authors' goal to identify evidence-based recommendations within the literature to help guide the process of designing a new registry with optimal efficiency, workability and data use. The objective of this study is to examine the primary literature for evidence-based recommendations on how to design and establish a cancer registry, with a focus on literature which analyses the performance and usefulness of already established registries or guidelines.

METHODS

An electronic search was completed in MEDLINE, CINAHL, EMCARE, SCOPUS and the Cochrane Database of Systematic Reviews. Recommendations were extracted from the identified articles and collated as themes.

RESULTS

Nine articles of varying quality were included in the review. Recommendations obtained from the literature included broad themes of the importance of clinician involvement, establishment of clear data definitions, number of variables used, inbuilt strategies to improve quality and completeness of data, considerations of costs, an 'opt-out' strategy for ethics and privacy and flexibility of the system.

CONCLUSION

This review concluded that there is a large gap in the primary literature for evidence-based recommendations on the design and establishment of cancer registries. The included articles established a small scope of relevant themes, which were largely non-specific. This area of deficiency provides an opportunity for future research, which would further strengthen the quality of current or new guidelines in cancer registry establishment.

Cancer staging at diagnosis data comparisons in South Australia

Cancer stage at diagnosis is an important gap for Australian population based cancer registries. The study aims to understand the quality and completeness of three different collections of cancer staging data. The South Australian Cancer Registry data collection for breast and colorectal cancer (CRC) cases diagnosed in 2011, was linked to Registry Derived Stage (RDS) data, pathology plus hospital metastasis codes (pathology stage), and the South Australian Clinical Cancer Registry Stage (SACCR stage). The agreement between staging systems was examined using kappa statistics. Kaplan-Meier curves and Cox regression were used to examine the difference in survival by staging methods. Among 2,530 breast and CRC cases 98.8% were stageable (n = 2,500) according to histology. Among stageable cases, 84.6% had RDS, 51.2% had pathology stage and 29.5% had SACCR stage. The kappa statistic for RDS and pathology stage was 0.930 for breast cancer and 0.973 for CRC, and 0.574 for RDS and SACCR stage for breast cancer and 0.632 for CRC. The agreement between pathology stage and SACCR stage was 0.430 for breast cancer and 0.528 for CRC. The distribution of stage was similar across staging methods, although more stage four cancers by pathology stage, and survival patterns were similar but not the same. The agreement was high between different staging systems. Pathology stage had a higher than expected stage 4 proportion. This study highlights an opportunity to collect stage information in a cost-effective manner, while collecting data that usefully represent stage at diagnosis across the population, for population based epidemiological analyses.

Is the risk of cancer in Australia overstated? The importance of competing mortality for estimating lifetime risk

OBJECTIVES

To calculate lifetime risks of cancer diagnosis and cancer-specific death, adjusted for competing mortality, and to compare these estimates with the corresponding risks published by the Australian Institute of Health and Welfare (AIHW).

DESIGN, SETTING

Analysis of publicly available annual AIHW data on age-specific cancer incidence and mortality - for breast cancer, colorectal cancer, prostate cancer, melanoma of the skin, and lung cancer - and all-cause mortality in Australia, 1982-2013.

OUTCOME MEASURES

Lifetime risks of cancer diagnosis and mortality (to age 85), adjusted for competing mortality.

RESULTS

During 1982-2013, AIHW estimates were consistently higher than our competing mortality-adjusted estimates of lifetime risks of diagnosis and death for all five cancers. Differences between AIHW and adjusted estimates declined with time for breast cancer, prostate cancer, colorectal cancer, and lung cancer (for men only), but remained steady for lung cancer (women only) and melanoma of the skin. In 2013, the respective estimated lifetime risks of diagnosis (AIHW and adjusted) were 12.7% and 12.1% for breast cancer, 18.7% and 16.2% for prostate cancer, 9.0% and 7.0% (men) and 6.4% and 5.5% (women) for colorectal cancer, 7.5% and 6.0% (men) and 4.4% and 4.0% (women) for melanoma of the skin, and 7.6% and 5.8% (men) and 4.5% and 3.9% (women) for lung cancer.

CONCLUSION

The method employed in Australia to calculate the lifetime risks of cancer diagnosis and mortality overestimates these risks, especially for men.

Comparison of cause of death between Australian and New Zealand Dialysis and Transplant Registry and the Australian National Death Index

AIM

The aim of the present study was to understand the differences in how cause of death for patients receiving renal replacement therapy in Australia is recorded in The Australian and New Zealand Dialysis and Transplant Registry (ANZDATA) compared to the National Death Index (NDI).

METHODS

Data linkage was performed between ANZDATA and NDI for all deaths in the period 1980-2013. Cause of death was classified according to ICD-10 chapter. Overall and chapter specific agreement were assessed using the Kappa statistic. Descriptive analysis was used to explore differences where there was disagreement on primary cause of death.

RESULTS

The analysis cohort included 28 675 patients. Ninety five percent of ANZDATA reported deaths fell within +/- 3 days of the date recorded by NDI. Circulatory death was the most common cause of death in both databases (ANZDATA 48%, NDI 32%). Overall agreement at ICD chapter level of primary cause was poor (36%, kappa 0.22). Agreement was best for malignancy (kappa 0.71). When there was disagreement on primary cause of death these were most commonly coded as genitourinary (35%) and endocrine (25.0%) in NDI, and circulatory (39%) and withdrawal (24%) in ANZDATA. Sixty-nine percent of patients had a renal related cause documented as either primary or a contributing cause of death in the NDI.

CONCLUSION

There is poor agreement in primary cause of death between ANZDATA and NDI which is in part explained by the absence of diabetes and renal failure as causes of death in ANZDATA and the absence of 'withdrawal' in NDI. These differences should be appreciated when interpreting epidemiological data on cause of death in the Australian end stage kidney disease population.

Development of a tool for comprehensive evaluation of population-based cancer registries

OBJECTIVE

Several methods have been suggested for evaluation of population-based cancer registries (PBCR) worldwide. However, most of these methods evaluate the data and outputs of the cancer registries. This study aimed to develop a comprehensive tool and protocol for evaluation of inputs, processes and outputs of a PBCR.

METHODS

The standards of the North American Association of Central Cancer Registries (NAACCR) were used to draft a comprehensive checklist. In addition, the national guidelines of PBCR were used to develop a questionnaire for evaluation of knowledge and practice of the PBCR personnel. Furthermore, a protocol for evaluation of the completeness and validity of the PBCR data was developed according to the International Agency for Research on Cancer (IARC) and the NAACCR guidelines. A 0-4 Likert based score and expert opinions (10 experts) were used to assess validity of the eight questionnaires/checklists. A modified Delphi method was applied to validate the checklists and questionnaires. Questions with a score higher than 3 remained in the final tools.

RESULTS

The final package consists of 546 questions including 108 (19.8%) for evaluation of guidelines, 54 (9.9%) for analysis and reports, 87 (15.9%) for governance and infrastructure, 155 (28.4%) for information technology, 21 (3.8%) for personnel knowledge and 121 (22.2%) for their practice. Additionally, data quality indicators were also considered for evaluation of PBCRs.

CONCLUSION

This comprehensive tool can be used to show the gaps and limitations of the PBCR programs and provide informative clues for their improvement.

A national study of the unmet needs of support persons of haematological cancer survivors in rural and urban areas of Australia

Purpose

This study aimed to compare support persons of haematological cancer survivors living in rural and urban areas in regard to the type, prevalence and factors associated with reporting unmet needs.

Methods

One thousand and four (792 urban and 193 rural) support persons of adults diagnosed with haematological cancer were recruited from five Australian state population-based cancer registries. Participants completed the Support Person Unmet Needs Survey (SPUNS) that assessed the level of unmet needs experienced over the past month across six domains.

Results

Overall, 66% of support persons had at least one ‘moderate, high or very high’ unmet need and 24% (n = 182) reported having multiple (i.e. 6 or more) ‘high/very high’ unmet needs in the past month. There were no significant differences between rural and urban support persons in the prevalence of multiple unmet needs or mean total unmet needs scores. There were however significant differences in the types of ‘high/very high’ unmet needs with support persons living in rural areas more likely to report finance-related unmet needs. Support persons who indicated they had difficulty paying bills had significantly higher odds of reporting multiple ‘high/very high’ unmet needs.

Conclusions

This is the first large, population-based study to compare the unmet needs of support persons of haematological cancer survivors living in rural and urban areas. Findings confirm previous evidence that supporting a person diagnosed with haematological cancer correlates with a high level of unmet needs and highlight the importance of developing systemic strategies for assisting support persons, especially in regard to making financial assistance and travel subsidies known and readily accessible to those living in rural areas.

Administrative data provide vital research evidence for maximizing health-system performance and outcomes

Although the quality of administrative data is frequently questioned, these data are vital for health-services evaluation and complement data from trials, other research studies and registries for research. Trials generally provide the strongest evidence of outcomes in research settings but results may not apply in many service environments. High-quality observational research has a complementary role where trials are not applicable and for assessing whether trial results apply to groups excluded from trials. Administrative data have a broader system-wide reach, enabling system-wide health-services research and monitoring of performance markers. Where administrative data raise questions about service outcomes, follow-up enquiry may be required to investigate validity and service implications. Greater use should be made of administrative data for system-wide monitoring and for research on service effectiveness and equity.

Melhora na qualidade e completitude da base de dados do Registro de Câncer de Base Populacional do município de São Paulo: uso das técnicas de linkage

RESUMO: A disponibilidade de grandes bases de dados informatizadas em saúde tornou a técnica de linkage uma alternativa para diferentes tipos de estudos, proporcionando a geração de uma base de dados mais completa e de baixo custo operacional. Objetivo: Melhorar a qualidade e a completitude dos casos incidentes de câncer por meio dos linkages probabilístico e determinístico entre o Registro de Câncer de Base Populacional de São Paulo (RCBP-SP), o banco de dados de óbitos e de Autorização e Procedimentos de Alta Complexidade. Método: Foi utilizado o banco de dados do RCBP-SP, composto de 343.306 casos de câncer incidentes no município de São Paulo entre 1997 e 2005, com idades entre 1 e 106 anos, de ambos os sexos. Para o linkage foram utilizadas três bases de dados, a saber: do Programa de Aprimoramento de Mortalidade no Município de São Paulo (PRO-AIM), da Fundação SEADE e da Autorização e Procedimentos de Alta Complexidade/Custo do Sistema de Informação Ambulatorial do Sistema Único de Saúde (APAC-SIA/SUS). Foram analisadas os coeficientes brutos de incidência (CBI) e mortalidade (CBM) e a sobrevida global pela técnica de Kaplan-Meier. Resultados: Após o linkage, verificou-se um ganho de 4,3% para a CBI e 25,8% para a CBM. Na análise de sobrevida global antes do linkage havia uma subestimação da probabilidade de estar vivo para todas as variáveis analisadas (p < 0,001). Conclusão: As técnicas de linkage contribuíram para a melhora da qualidade da informação do RCBP-SP tanto na completitude das variáveis quanto na definição do status vital do paciente, refletindo a capacidade das bases de dados, quando trabalhadas de maneira conjunta, de fornecerem subsídios para diversos tipos de estudos e informações para o planejamento de ações políticas e estratégicas.