Large differences in patterns of breast cancer survival between Australia and England: A comparative study using cancer registry data

Survival from breast cancer in the UK is lower than in other countries in Western Europe, the USA and Australia. However, these international differences have not yet been examined in relation to tumor characteristics, treatment, screening history or other prognostic factors. We calculated relative survival by age, period of diagnosis, category of unemployment and extent of disease for women diagnosed with breast cancer during the period 1980–2002 in New South Wales (Australia) and West Midlands (England). National cancer registry data for each country for the period 1990–1994 were also examined. The excess hazard ratio was modeled as a function of prognostic covariables. Survival in Australia and New South Wales was higher than in England and West Midlands, respectively. In both regions, survival was lower for more deprived women and for the elderly. These differences were greater in West Midlands. Survival from localized and regional disease in New South Wales was higher than in West Midlands, but survival from metastatic disease was similar. Differences in breast cancer survival are unlikely to be entirely due to differences in data quality or to limitations of the analyses, although the measure of extent of disease used may not have been adequate to elucidate the effect of stage fully. One possible causal explanation is that the management of breast cancer differs between these regions. Further research should acquire better data on stage and investigate the effect of comorbidity and of patterns of care upon the difference in breast cancer survival between England and Australia. © 2008 Wiley‐Liss, Inc.     

Trends and socioeconomic inequalities in cancer survival in England and Wales up to 2001

We examined national trends and socioeconomic inequalities in cancer survival in England and Wales during the 1990s, using population-based data on 2.2 million patients who were diagnosed with one of the 20 most common cancers between 1986 and 1999 and followed up to 2001. Patients were assigned to one of five deprivation categories (from 'affluent' to 'deprived') using characteristics of their electoral ward of residence at diagnosis. We estimated relative survival up to 5 years after diagnosis, adjusting separately in each deprivation category for background mortality by age, sex and calendar period. We estimated trends in survival and in the difference in survival between deprivation categories ('deprivation gap') over the periods 1986-90, 1991-95 and 1996-99. We used period analysis to examine likely survival rates in the near future. Survival improved for most cancers in both sexes during the 1990s, and appears likely to continue improving for most cancers in the near future. The deprivation gap in survival between rich and poor was wider for patients diagnosed in the late 1990s than in the late 1980s. Increases in cancer survival in England and Wales during the 1990s are shown to be significantly associated with a widening deprivation gap in survival.     

Predicted trends in long-term breast cancer survival in England and Wales

Trends in long-term relative survival from breast cancer are examined for women diagnosed in England and Wales up to 2001, using both period and hybrid approaches. Large improvements in long-term survival are predicted. Women with breast cancer still experience persistent excess mortality up to at least 20 years after diagnosis.     

Socioeconomic inequalities in cancer survival in Scotland 1986-2000

We analysed trends in 5-year survival of the 18 commonest cancers in Scotland diagnosed between 1986 and 2000 and followed up to 2004 in each of five deprivation groups based on patients postcode of residence at diagnosis. We estimated relative survival up to 5 years after diagnosis, adjusting for the different background mortality in each deprivation group by age, sex and calendar period. We estimated trends in overall survival and in the deprivation gap in survival up to 2004. Five-year survival improved for all malignancies except bladder cancer and was associated with a widening in the deprivation gap in survival. For 25 of 30 cancer-sex combinations examined, 5-year survival was lower among more deprived patients diagnosed during 1996-2000, and the deprivation gap in survival had widened since 1986-1990 for 15 of these 25 cancers, similar to the trends seen in England and Wales.     

Up-to-date survival curves of children with cancer by period analysis

Survival rates of children with cancer have strongly improved during the past decades, but much of this improvement has been disclosed with substantial delay by traditional methods of survival analysis, which reflect survival experience of patients diagnosed many years ago. In this paper, the use of a new method of survival analysis, denoted period analysis, for providing more up-to-date estimates of 10-year survival curves of children with cancer is empirically evaluated using data of the Surveillance, Epidemiology, and End Results Program of the United States National Cancer Institute. It is shown that period analysis provides much more up-to-date estimates of survival curves than traditional cohort-based survival analysis indeed, at least as long as there is ongoing improvement in survival rates over time, as it seems to be the case for many forms of childhood cancer. The most recent 10-year period survival estimates indicate that survival rates of children with cancer achieved by the end of the 20th century are substantially higher than previously available survival statistics have suggested. Application of period analysis may be particularly useful in the field of childhood cancer as it may help to prevent patients, their families and clinicians from being burdened by outdated, often too pessimistic survival expectations.     

Period versus cohort modeling of up-to-date cancer survival

Recently, 2 modeling strategies have been proposed and shown to be useful to increase precision of up-to-date cancer survival estimates and to predict cancer patient survival: modeled period analysis and modeled cohort analysis. We aimed to compare the performance of both types of modeling for providing up-to-date and precise cancer survival estimates. Data from the nationwide Finnish Cancer Registry were used to assess how well both approaches would have been able to predict 5-year relative survival of concurrently diagnosed patients if they had been applied for that purpose throughout the past decades. Analyses were carried out for 20 common forms of cancer. For each cancer, 5-year relative survival was modeled with either approach for each single calendar year from 1962 to 1997. Mean differences and mean squared differences from 5-year relative survival later observed for patients diagnosed in the 5-year period around those calendar years were calculated. Survival estimates obtained by period modeling had much lower standard errors than those obtained by cohort modeling. Furthermore, for a clear majority of cancers, period modeling on average also provided better prediction of 5-year relative survival than cohort modeling. We conclude that, although both modeling strategies have their merits and specific indications, period modeling of survival has distinct advantages for up-to-date and precise estimation of cancer survival in population-based cancer survival studies.     

Up‐to‐date cancer survival: Period analysis and beyond

Since its introduction in 1996, period analysis has been shown to be useful for deriving more up‐to‐date cancer survival estimates, and the method is now increasingly used for that purpose in national and international cancer survival studies. However, period analysis, like other commonly employed methods, is just a special case from a broad class of design options in the analysis of cancer survival data. Here, we explore a broader range of design options, including 2 model‐based approaches, for deriving up‐to‐date estimates of 5‐ and 10‐year relative survival for patients diagnosed in the most recent 5‐year interval for which data are available. The performance of the various designs is evaluated empirically for 20 common forms of cancer using more than 50‐year long time series of data from the Finnish Cancer Registry. Period analysis as well as the 2 model‐based approaches, one using a “cohort‐type model” and another using a “period‐type model”, all performed better than traditional cohort or complete analysis. Compared with “standard period analysis”, the cohort‐type model further increased up‐to‐dateness of survival estimates, whereas the period‐type model increased their precision. While our analysis confirms advantages of period analysis over traditional methods in terms of up‐to‐dateness of cancer survival data, further improvements are possible by flexible use of model‐based approaches. © 2008 Wiley‐Liss, Inc.     

Estimating relative survival among people registered with cancer in England and Wales.

Because routinely collected survival data for cancer patients in England and Wales do not typically specify cause of death, conventional estimates of survival in cancer patients based on such data are a measure of their mortality from all causes rather than their mortality due to cancer. As a result, trends in survival over time are difficult to interpret because changes in overall survival may well reflect changes in the risk of death from other causes, rather than from the cancer of interest. One way of overcoming this problem is to use some form of 'relative survival' defined as a measure of survival corrected for the effect of other independent causes of death. Since this concept was first introduced, various methods for calculating relative survival have been proposed and this had led to some confusion as to the most appropriate choice of estimate. This paper aims to provide an introduction to the concept of relative survival and reviews some of the suggested methods of estimation. In addition, a particularly simple, but robust approach, is highlighted based on expected and observed mortality. This method is illustrated using preliminary data from the Office for National Statistics on cancer survival in patients born after 1939 and diagnosed with cancer during 1972-84. The examples presented, although limited to analyses on a small number of selected sites, highlight some encouraging trends in survival in people aged under 35 diagnosed with leukaemia, Hodgkin's disease and testicular cancer during this period.     

Disclosing progress in cancer survival with less delay

Cancer registration plays a key role in monitoring the burden of cancer. However, cancer registry (CR) data are usually made available with substantial delay to ensure best possible completeness of case ascertainment. Here, we investigate empirically with routinely available data whether such a delay is mandatory for survival analyses or whether data can be used earlier to provide more up-to-date survival estimates. We compared distributions of prognostic factors and period relative survival estimates for three population-based CRs in Germany (Schleswig-Holstein (SH), Rhineland-Palatinate (RP), Saarland (SA)) computed on datasets extracted one (DY+1) to 5 years after the year of diagnosis (DY+5; reference). Analyses were conducted for seven cancer sites and various survival analyses scenarios. The proportion of patients registered in the datasets at a given time varied strongly across registries with 57% (SH), 2% (RP) and 26% (SA) registered in DY+1 and >93% in all registries in DY+3. Five-year survival estimates for the most recent three-year period were comparable to estimates from the reference dataset already in DY+1 (mean absolute deviations = 0.2–0.6% units). Deviations >1% units were only observed for pancreatic and lung cancer in RP and leukemia in SA (all ≤1.5% units). For estimates of 1-year survival based on the most recent 1-year period only, slightly longer delays were required, but reasonable estimates were still obtained after 1–2 years, depending on the CR and cancer site. Thus, progress in cancer survival could be disclosed in a more timely manner than commonly practiced despite delays in completeness of registration.     

Study populations for period analyses of cancer survival

Background:

Period analysis is increasingly used to compute long-term cancer survival, as it provides better prediction of survival of newly diagnosed patients than traditional cohort analysis. However, the patient population to which period survival estimates best pertain to and which should be described in a study is less obvious.

Methods:

Using Finnish Cancer Registry data on 23 common cancer sites, age-standardized period estimates of 5-, 10-, 15-, and 20-year relative survival were computed for each 2-, 5-, and 10-year calendar period in 1954–2003 and compared with survival estimates for two cohorts by means of mean, mean absolute and mean squared differences: a full cohort of all patients potentially contributing some data to the survival analysis and a restricted cohort of patients diagnosed in the period of interest.

Results:

In most computations, survival estimates for the full cohorts were on average closer to the period estimates for the majority of cancer sites. For 10-year survival, results were less obvious with respect to the mean difference. However, mean squared and mean absolute differences were smaller for the majority of cancers when using the full cohort.

Conclusion:

Our results suggest that the full cohort should be described in reports of period survival analysis.     

Long-term survival of cancer patients in Germany achieved by the beginning of the third millenium.

BACKGROUND: Over the last decades, long-term survival rates have substantially increased for many forms of cancer. However, these improvements have often been detected with substantial delay by traditional methods of survival analyses. PATIENTS AND METHODS: Using data of the population-based Saarland Cancer Registry, 5- and 10-year relative survival rates were derived for patients with 24 common forms of cancer in Saarland/Germany for the years 2000-2002 by period analysis and compared with conventional cohort estimates of 5- and 10-year relative survival rates pertaining to patients diagnosed in 1990-1992. RESULTS: For many forms of cancer, the 2000-2002 period survival estimates were substantially higher than the corresponding estimates for the cohorts of patients diagnosed in 1990-1992. For example, 10-year relative survival rates achieved in 2000-2002 were close to 100% for patients with testis and thyroid cancer, >85% for patients with melanomas of the skin, approximately 80% for patients with endometrial cancer and prostate cancer, close to 70% for patients with breast cancer and kidney cancer, and close to 60% for patients with colon cancer and lymphomas. CONCLUSIONS: Survival expectations of patients diagnosed with cancer at the beginning of the third millenium are substantially higher than previously available survival statistics have suggested.     

Survival trends for small intestinal cancer in England and Wales, 1971-1990: national population-based study

This population-based study examines prognostic factors and survival trends among adults (15-99 years) diagnosed with small intestinal cancer in England and Wales during 1971-1990 and followed up to 1995. During this period, the 1- and 5-year age-standardised relative survival rates for small intestinal cancers combined were 42% and 23%, respectively. Duodenal tumours, adenocarcinomas, men, patients with advanced age and the most deprived patients had the poorest prognosis. For all small bowel tumours combined, the excess risk of death fell significantly by 6-9% every 4 years over the 20-year period (adjusted excess hazard ratio (EHR) 0.91 at 1 year after diagnosis, 0.94 at 5 years). For duodenal tumours, the EHR fell by about 14% (95% CI 5-22%) every 4 years between 1979 and 1990, and a similar trend for jejunal tumours was of borderline significance. Further population-based investigations linking survival data to individual data on diagnostic methods and types of treatment are needed.     

Geographical and temporal distribution of cancer survival in teenagers and young adults in England

Background:

Between 1979 and 2001, an analysis of cancer survival in young people in England, aged 13 to 24 years, showed overall improvements. However, for some diagnostic groups, little or no increases were observed. The aim of this study was to analyse the regional distribution of cancer survival in teenagers and young adults in England in order to identify patterns and potential for improvements at a regional scale.

Methods:

We examined geographical and temporal patterns in relative survival in cancer patients aged 13–24 years in England during the time period 1979–2001. Cancer cases were grouped according to an internationally recognised morphology-based diagnostic scheme.

Results:

For most diagnostic groups, there was little variation in survival between regions, except for testicular germ cell tumours (P=0.006) and colorectal carcinoma (P=0.002). For certain diagnostic groups, the temporal pattern in survival differed between regions. However, in regions that showed poor survival during the early part of the study period, greatest improvements were observed in groups such as acute lymphoid leukaemia, acute myeloid leukaemia, testicular tumours and melanoma.

Conclusion:

In conclusion, there was a reduction in the differences in survival between regions during the study period.     

Is cancer survival associated with cancer symptom awareness and barriers to seeking medical help in England? An ecological study

Background:

Campaigns aimed at raising cancer awareness and encouraging early presentation have been implemented in England. However, little is known about whether people with low cancer awareness and increased barriers to seeking medical help have worse cancer survival, and whether there is a geographical variation in cancer awareness and barriers in England.

Methods:

From population-based surveys (n=35 308), using the Cancer Research UK Cancer Awareness Measure, we calculated the age- and sex-standardised symptom awareness and barriers scores for 52 primary care trusts (PCTs). These measures were evaluated in relation to the sex-, age-, and type of cancer-standardised cancer survival index of the corresponding PCT, from the National Cancer Registry, using linear regression. Breast, lung, and bowel cancer survival were analysed separately.

Results:

Cancer symptom awareness and barriers scores varied greatly between geographical regions in England, with the worst scores observed in socioeconomically deprived parts of East London. Low cancer awareness score was associated with poor cancer survival at PCT level (estimated slope=1.56, 95% CI: 0.56; 2.57). The barriers score was not associated with overall cancer survival, but it was associated with breast cancer survival (estimated slope=−0.66, 95% CI: −1.20; −0.11). Specific barriers, such as embarrassment and difficulties in arranging transport to the doctor''s surgery, were associated with worse breast cancer survival.

Conclusions:

Cancer symptom awareness and cancer survival are associated. Campaigns should focus on improving awareness about cancer symptoms, especially in socioeconomically deprived areas. Efforts should be made to alleviate barriers to seeking medical help in women with symptoms of breast cancer.     

Current trends in colorectal cancer: site, incidence, mortality and survival in England and Wales

The objective was to examine trends in colorectal cancer (CRC) incidence and mortality in England and Wales over the last 30 years. Age-standardized incidence, mortality and survival rates for CRC, based on data from the National Cancer Intelligence Centre at the Office for National Statistics, were calculated and trends assessed.Between 1971 and 1997 the total number of cases of CRC increased by 42%, from 20 400 to 28 900. The site distribution of CRC between 1971 and 1994 was: rectum 38%, sigmoid 29%, caecum 15%, transverse colon and flexures 10%, ascending colon 5%, and descending colon 3%. Between 1971 and 1997 the direct age- standardized incidence increased by 20% in males and by 5% in females. The direct age-standardized mortality fell by 24% in males and by 37% in females. Age-standardized relative 5–year survival in adults improved from 22%–27% for patients diagnosed during 1971–1975 to over 40% for those diagnosed during the period 1991–1993.In conclusion, the incidence of CRC in England and Wales has been steadily rising. It is more common in males and has increased more rapidly in males than in females. The reasons for these trends remain unclear. Five-year survival has improved substantially, but rates are still below those in comparable countries elsewhere in Europe and in the USA.     

Up-to-date monitoring of childhood cancer long-term survival in Europe: tumours of the sympathetic nervous system, retinoblastoma, renal and bone tumours, and soft tissue sarcomas.

BACKGROUND: Prognosis for most types of childhood tumours has improved during the last few decades. In this article we estimate up-to-date period survival for less common, but important childhood malignancies in Europe. METHODS: Using the database of the Automated Childhood Cancer Information System we calculated period estimates of 10-year survival for the 1995-1999 period for children aged 0-14 years diagnosed during 1985-1999 with tumours of the sympathetic nervous system (NS), retinoblastoma, renal tumours, bone tumours and soft tissue sarcomas in four European regions. RESULTS: Ten-year period survival for 1995-1999 was 66% in children with tumours of the sympathetic NS, 96% for retinoblastoma, 87% for renal tumours, 58% for bone tumours and 61% for soft tissue sarcomas. The higher period estimates, as compared with cohort and complete estimates indicate recent improvement in survival for tumours of the sympathetic NS and to a lesser extent for retinoblastoma and renal tumours. Region-specific period survival estimates were lowest for Eastern Europe for renal, bone and soft tissue tumours, but not for the other two tumour groups. CONCLUSION: There have been further improvements in the 1990s in long-term survival of children diagnosed with several malignancies, albeit to a different extent in different European regions.     

No socioeconomic inequalities in colorectal cancer survival within a randomised clinical trial

There is strong evidence that colorectal cancer survival differs between socioeconomic groups. We analysed data on 2481 patients diagnosed during 1989–1997 and recruited to a randomised controlled clinical trial (AXIS, ISRCTN32414363) of chemotherapy and radiotherapy for colorectal cancer. Crude and relative survival at 1 and 5 years was estimated in five categories of socioeconomic deprivation. Multiple imputation was used to account for missing data on tumour stage. A multivariable fractional polynomial model was fitted to estimate the excess hazard of death in each deprivation category, adjusting for the confounding effects of age, stage, cancer site (colon, rectum) and sex, using generalised linear models. Relative survival in the trial patients was higher than in the general population of England and Wales. The socioeconomic gradient in survival was much smaller than that seen for colorectal cancer patients in the general population, both at 1 year −3.2% (95% CI −7.3 to 1.0%, P=0.14) and at 5 years −1.7% (95% CI −8.3 to 4.9%, P=0.61). Given equal treatment, colorectal cancer survival in England and Wales does not appear to depend on socioeconomic status, suggesting that the socioeconomic gradient in survival in the general population could well be due to health-care system factors.     

Estimating breast cancer‐specific and other‐cause mortality in clinical trial and population‐based cancer registry cohorts

BACKGROUND:

To compute net cancer‐specific survival rates using population data sources (eg, the National Cancer Institute's Surveillance, Epidemiology, and End Results [SEER] Program), 2 approaches primarily are used: relative survival (observed survival adjusted for life expectancy) and cause‐specific survival based on death certificates. The authors of this report evaluated the performance of these estimates relative to a third approach based on detailed clinical follow‐up history.

METHODS:

By using data from Cancer Cooperative Group clinical trials in breast cancer, the authors estimated 1) relative survival, 2) breast cancer‐specific survival (BCSS) determined from death certificates, and 3) BCSS obtained by attributing cause according to clinical events after diagnosis, which, for this analysis was considered the benchmark “true” estimate. Noncancer life expectancy also was compared between trial participants, SEER registry patients, and the general population.

RESULTS:

Among trial patients, relative survival overestimated true BCSS in patients with lymph node‐negative breast cancer; whereas, in patients with lymph node‐positive breast cancer, the 2 estimates were similar. For higher risk patients (younger age, larger tumors), relative survival accurately estimated true BCSS. In lower risk patients, death certificate BCSS was more accurate than relative survival. Noncancer life expectancy was more favorable among trial participants than in the general population and among SEER patients. Tumor size at diagnosis, which is a potential surrogate for screening use, partially accounted for this difference.

CONCLUSIONS:

In the clinical trials, relative survival accurately estimated BCSS in patients who had higher risk disease despite more favorable other‐cause mortality than the population at large. In patients with lower risk disease, the estimate using death certificate information was more accurate. For SEER data and other data sources where detailed postdiagnosis clinical history was unavailable, death certificate‐based estimates of cause‐specific survival may be a superior choice. Cancer 2009. © 2009 American Cancer Society.     

Age adjustment of cancer survival rates: methods, point estimates and standard errors

We empirically evaluated the performance of a new method for age adjustment of cancer survival compared to traditional age adjustment using data from the Finnish Cancer Registry. We find that both methods provide almost identical results for absolute survival but the new method generally provides more meaningful estimates of relative survival with often a smaller standard error.     

Trends in eye cancer mortality among adults in the USA and England and Wales.

Trends in eye cancer mortality are presented for the USA and England and Wales during the period 1955-89. Mortality rates have fallen by 58% in the USA during this period. The fall in mortality is paralleled by an equal fall in incidence rates in the USA. In England and Wales, mortality rates and incidence rates have remained relatively constant during the last three decades. The explanation for these differences between the USA and England and Wales is unknown.