Hui You

Global surveillance of cancer survival 1995–2009: analysis of individual data for 25 676 887 patients from 279 population-based registries in 67 countries (CONCORD-2)

BACKGROUND Worldwide data for cancer survival are scarce. We aimed to initiate worldwide surveillance of cancer survival by central analysis of population-based registry data, as a metric of the effectiveness of health systems, and to inform global policy on cancer control. METHODS Individual tumour records were submitted by 279 population-based cancer registries in 67 countries for 25·7 million adults (age 15-99 years) and 75,000 children (age 0-14 years) diagnosed with cancer during 1995-2009 and followed up to Dec 31, 2009, or later. We looked at cancers of the stomach, colon, rectum, liver, lung, breast (women), cervix, ovary, and prostate in adults, and adult and childhood leukaemia. Standardised quality control procedures were applied; errors were corrected by the registry concerned. We estimated 5-year net survival, adjusted for background mortality in every country or region by age (single year), sex, and calendar year, and by race or ethnic origin in some countries. Estimates were age-standardised with the International Cancer Survival Standard weights. FINDINGS 5-year survival from colon, rectal, and breast cancers has increased steadily in most developed countries. For patients diagnosed during 2005-09, survival for colon and rectal cancer reached 60% or more in 22 countries around the world; for breast cancer, 5-year survival rose to 85% or higher in 17 countries worldwide. Liver and lung cancer remain lethal in all nations: for both cancers, 5-year survival is below 20% everywhere in Europe, in the range 15-19% in North America, and as low as 7-9% in Mongolia and Thailand. Striking rises in 5-year survival from prostate cancer have occurred in many countries: survival rose by 10-20% between 1995-99 and 2005-09 in 22 countries in South America, Asia, and Europe, but survival still varies widely around the world, from less than 60% in Bulgaria and Thailand to 95% or more in Brazil, Puerto Rico, and the USA. For cervical cancer, national estimates of 5-year survival range from less than 50% to more than 70%; regional variations are much wider, and improvements between 1995-99 and 2005-09 have generally been slight. For women diagnosed with ovarian cancer in 2005-09, 5-year survival was 40% or higher only in Ecuador, the USA, and 17 countries in Asia and Europe. 5-year survival for stomach cancer in 2005-09 was high (54-58%) in Japan and South Korea, compared with less than 40% in other countries. By contrast, 5-year survival from adult leukaemia in Japan and South Korea (18-23%) is lower than in most other countries. 5-year survival from childhood acute lymphoblastic leukaemia is less than 60% in several countries, but as high as 90% in Canada and four European countries, which suggests major deficiencies in the management of a largely curable disease. INTERPRETATION International comparison of survival trends reveals very wide differences that are likely to be attributable to differences in access to early diagnosis and optimum treatment. Continuous worldwide surveillance of cancer survival should become an indispensable source of information for cancer patients and researchers and a stimulus for politicians to improve health policy and health-care systems. FUNDING Canadian Partnership Against Cancer (Toronto, Canada), Cancer Focus Northern Ireland (Belfast, UK), Cancer Institute New South Wales (Sydney, Australia), Cancer Research UK (London, UK), Centers for Disease Control and Prevention (Atlanta, GA, USA), Swiss Re (London, UK), Swiss Cancer Research foundation (Bern, Switzerland), Swiss Cancer League (Bern, Switzerland), and University of Kentucky (Lexington, KY, USA).

Estimates of cancer incidence, mortality and survival in aboriginal people from NSW, Australia

BackgroundAboriginal status has been unreliably and incompletely recorded in health and vital registration data collections for the most populous areas of Australia, including NSW where 29% of Australian Aboriginal people reside. This paper reports an assessment of Aboriginal status recording in NSW cancer registrations and estimates incidence, mortality and survival from cancer in NSW Aboriginal people using multiple imputation of missing Aboriginal status in NSW Central Cancer Registry (CCR) records.MethodsLogistic regression modelling and multiple imputation were used to assign Aboriginal status to those records of cancer diagnosed from 1999 to 2008 with missing Aboriginality (affecting 12-18% of NSW cancers registered in this period). Estimates of incidence, mortality and survival from cancer in NSW Aboriginal people were compared with the NSW total population, as standardised incidence and mortality ratios, and with the non-Aboriginal population.ResultsFollowing imputation, 146 (12.2%) extra cancers in Aboriginal males and 140 (12.5%) in Aboriginal females were found for 1999-2007. Mean annual cancer incidence in NSW Aboriginal people was estimated to be 660 per 100,000 and 462 per 100,000, 9% and 6% higher than all NSW males and females respectively. Mean annual cancer mortality in NSW Aboriginal people was estimated to be 373 per 100,000 in males and 240 per 100,000 in females, 68% and 73% higher than for all NSW males and females respectively. Despite similar incidence of localised cancer, mortality from localised cancer in Aboriginal people is significantly higher than in non-Aboriginal people, as is mortality from cancers with regional, distant and unknown degree of spread at diagnosis. Cancer survival in Aboriginal people is significantly lower: 51% of males and 43% of females had died of the cancer by 5 years following diagnosis, compared to 36% and 33% of non-Aboriginal males and females respectively.ConclusionThe present study is the first to produce valid and reliable estimates of cancer incidence, survival and mortality in Australian Aboriginal people from NSW. Despite somewhat higher cancer incidence in Aboriginal than in non-Aboriginal people, substantially higher mortality and lower survival in Aboriginal people is only partly explained by more advanced cancer at diagnosis.

What factors are predictive of surgical resection and survival from localised non- small cell lung cancer?

Objective: To investigate opportunities to reduce lung cancer mortality after diagnosis of localised non‐small cell lung cancer (NSCLC) in New South Wales through surgical resection.

Socio-demographic disadvantage and distant summary stage of cancer at diagnosis--A population-based study in New South Wales.

BACKGROUND Past studies generally indicate that socio-demographic disadvantage is associated with lower cancer survival but evidence of an association with stage of cancer at diagnosis has been less consistent. This study examines the associations between distant summary stage and remoteness, socio-economic status and country of birth in New South Wales for invasive cancers overall and by cancer site. METHODS The population-based New South Wales Central Cancer Registry was used to obtain data on all cases diagnosed in 1980-2009 (n=699,382). Logistic regression models were used to compute odds ratios (ORs) with 95% confidence intervals (CIs) for odds of distant summary stage at diagnosis. RESULTS A higher likelihood of being diagnosed with distant cancer was detected for those living in the most socio-economically disadvantaged areas compared with the least disadvantaged areas (OR 1.27, 95% CI 1.24-1.30) and for those born in other English and non-English speaking countries compared with Australian-born (OR 1.10, 95% CI 1.07-1.12 and OR 1.12, 95% CI 1.10-1.14, respectively) after adjusting for age, sex, diagnostic period, remoteness, socio-economic status and country of birth. Cases living in inner (OR 0.90, 95% CI 0.88-0.91) and outer regional (OR 0.92, 95% CI 0.89-0.94) areas were less likely to be diagnosed with distant stage than cases living in major cities. Odds of distant stage increased over time for those living in socio-economically disadvantaged areas. In cancer site-specific analyses, living in socio-economically disadvantaged areas was generally a stronger predictor of distant stage than remoteness or country of birth. CONCLUSION Our results highlight the importance of lower socio-economic status as a predictor of distant stage at diagnosis. Socio-demographic disadvantage patterns varied for specific cancers, but in general, policy actions are recommended that emphasize earlier detection of cancers in people from lower socio-economic areas.

After accounting for competing causes of death and more advanced stage, do Aboriginal and Torres Strait Islander peoples with cancer still have worse survival? A population-based cohort study in New South Wales

BackgroundAboriginal and Torres Strait Islander peoples in Australia have been found to have poorer cancer survival than non-Aboriginal people. However, use of conventional relative survival analyses is limited due to a lack of life tables. This cohort study examined whether poorer survival persist after accounting for competing risks of death from other causes and disparities in cancer stage at diagnosis, for all cancers collectively and by cancer site.MethodsPeople diagnosed in 2000–2008 were extracted from the population-based New South Wales Cancer Registry. Aboriginal status was multiply imputed for people with missing information (12.9%). Logistic regression models were used to compute odds ratios (ORs) with 95% confidence intervals (CIs) for ‘advanced stage’ at diagnosis (separately for distant and distant/regional stage). Survival was examined using competing risk regression to compute subhazard ratios (SHRs) with 95%CIs.ResultsOf the 301,356 cases, 2517 (0.84%) identified as Aboriginal (0.94% after imputation). After adjusting for age, sex, year of diagnosis, socio-economic status, remoteness, and cancer site Aboriginal peoples were more likely to be diagnosed with distant (OR 1.30, 95%CI 1.17–1.44) or distant/regional stage (OR 1.29, 95%CI 1.18–1.40) for all cancers collectively. This applied to cancers of the female breast, uterus, prostate, kidney, others (those not included in other categories) and cervix (when analyses were restricted to cases with known stages/known Aboriginal status). Aboriginal peoples had a higher hazard of death than non-Aboriginal people after accounting for competing risks from other causes of death, socio-demographic factors, stage and cancer site (SHR 1.40, 95%CI 1.31–1.50 for all cancers collectively). Consistent results applied to colorectal, lung, breast, prostate and other cancers.ConclusionsAboriginal peoples with cancer have an elevated hazard of cancer death compared with non-Aboriginal people, after accounting for more advanced stage and competing causes of death. Further research is needed to determine reasons, including any contribution of co-morbidity, lifestyle factors and differentials in service access to help explain disparities.

Has cancer survival improved for older people as for younger people? New South Wales, 1980–2012

BACKGROUND Cancer survival has improved markedly in Australia for all ages but it is still lower in older patients. We hypothesize that the survival gap by age has increased. Our rationale is that treatment constraints in older people and potentially their limited participation in trials may have limited opportunities for survival gain. METHODS Post-diagnostic five-year cancer-specific mortality rates were analysed by age group for cancers recorded on the NSW Cancer Registry. Live cases were censored on December 31st, 2012. Hazards ratios (HRs) were obtained from proportional hazards regression for 1990-99 and 2000-12 diagnostic periods, using 1980-89 as the reference, adjusting for socio-demographic factors, degree of cancer spread, and for all cancers combined, for cancer sites. RESULTS Five-year mortality reduced by diagnostic period for all cancers collectively from 53% in 1980-89 to 33% in 2000-12, with decreases for separate cancer sites. Adjusted HRs (95% confidence intervals) were 0.78 (0.77, 0.80) for 1990-99 and 0.61 (0.58, 0.63) for 2000-12 for all cancers combined. The downward trend in HRs was smaller for the 80+ year age group, leading to significantly higher HRs of 0.83 (0.81, 0.87) and 0.73 (0.70, 0.76) for 1990-99 and 2000-12 respectively. Results were similar using competing risk regression and 5-year rather than 10-year age strata. CONCLUSION The reduction in cancer mortality was smaller in older people, as seen in the USA. Research is needed to achieve the best trade-offs between cancer control and harm avoidance in older people. Multidisciplinary teams have an important contribution to make.

Does exclusion of cancers registered only from death-certificate information diminish socio-demographic disparities in recorded survival?

BACKGROUND Death Certificate Only (DCO) cancer cases are commonly excluded from survival analyses due to unknown survival time. This study examines whether socio-demographic factors are associated with DCO diagnosis, and the potential effects of excluding DCO cases on socio-demographic cancer survival disparities in NSW, Australia. METHODS NSW Cancer Registry data for cases diagnosed in 2000-2008 were used in this study. Logistic regression was used to estimate the odds of DCO registration by socio-demographic sub-group (socio-economic disadvantage, residential remoteness, country of birth, age at diagnosis). Cox proportional hazard regression was used to estimate the probability of death from cancer by socio-demographic subgroup when DCO cases were included and excluded from analyses. RESULTS DCO cases consisted of 1.5% (n=4336) of all cases (n=299,651). DCO diagnosis was associated with living in socio-economically disadvantaged areas (most disadvantaged compared with least disadvantaged quintile: odds ratio OR 1.25, 95%CI 1.12-1.40), living in inner regional (OR 1.16, 95%CI 1.08-1.25) or remote areas (OR 1.48, 95%CI 1.01-2.19), having an unknown country of birth (OR 1.63, 95%CI 1.47-1.81) and older age. Including or excluding DCO cases had no significant impact on hazard ratios for cancer death by socio-economic disadvantage quintile or remoteness category, and only a minor impact on hazard ratios by age. CONCLUSION Socio-demographic factors were associated with DCO diagnosis in NSW. However, socio-demographic cancer survival disparities remained unchanged or varied only slightly irrespective of including/excluding DCO cases. Further research could examine the upper limits of DCO proportions that significantly alter estimated cancer survival differentials if DCOs are excluded.

The impact of geographic unit of analysis on socioeconomic inequalities in cancer survival and distant summary stage - a population-based study

Objective: When using area‐level disadvantage measures, size of geographic unit can have major effects on recorded socioeconomic cancer disparities. This study examined the extent of changes in recorded socioeconomic inequalities in cancer survival and distant stage when the measure of socioeconomic disadvantage was based on smaller Census Collection Districts (CDs) instead of Statistical Local Areas (SLAs).