Five-year Relative Survival Estimates Research Articles

Ovarian cancer survival population differences: a "high resolution study" comparing Philippine residents, and Filipino-Americans and Caucasians living in the US

BackgroundIn contrast to most other forms of cancer, data from some developing and developed countries show surprisingly similar survival rates for ovarian cancer. We aimed to compare ovarian cancer survival in Philippine residents, Filipino-Americans and Caucasians living in the US, using a high resolution approach, taking potential differences in prognostic factors into account.MethodsUsing databases from the SEER 13 and from the Manila and Rizal Cancer Registries, age-adjusted five-year absolute and relative survival estimates were computed using the period analysis method and compared between Filipino-American ovarian cancer patients with cancer patients from the Philippines and Caucasians in the US. Cox proportional hazards modelling was used to determine factors affecting survival differences.ResultsDespite more favorable distribution of age and cancer morphology and similar stage distribution, 5-year absolute and relative survival were lower in Philippine residents (Absolute survival, AS, 44%, Standard Error, SE, 2.9 and Relative survival, RS, 49.7%, SE, 3.7) than in Filipino-Americans (AS, 51.3%, SE, 3.1 and RS, 54.1%, SE, 3.4). After adjustment for these and additional covariates, strong excess risk of death for Philippine residents was found (Relative Risk, RR, 2.45, 95% confidence interval, 95% CI, 1.99-3.01). In contrast, no significant differences were found between Filipino-Americans and Caucasians living in the US.ConclusionMultivariate analyses disclosed strong survival disadvantages of Philippine residents compared to Filipino-American patients, for which differences in access to health care might have played an important role. Survival is no worse among Filipino-Americans than among Caucasians living in the US.

Trends in the Incidence and Survival of Cancer in Teenagers and Young Adults: Regional Analysis for South East England 1960–2002

Aims This study aimed to describe trends in the incidence and survival of cancer in teenagers and young adults in South East England between 1960 and 2002, and the influence of socioeconomic status upon survival. Materials and methods Data on 1788 patients aged 15–24 years were extracted from the Thames Cancer Registry, assigning each to a diagnostic group using the Birch and Marsden classification. Age-specific incidence rates in 5-year periods for the age groups 15–19 and 20–24 years were calculated for each diagnosis. Five-year relative survival estimates by diagnostic group were calculated for both age groups using 5-year periods of follow-up and non-overlapping years of diagnosis. To calculate overall survival estimates by socioeconomic group, the 10-year follow-up period 1993–2002 was used. Results Overall incidence rates were 162 per million person-years in 15–19 year olds and 261 in 20–24 year olds. We found a higher overall incidence in males, in 20–24 year olds and an increasing incidence over the last four decades, particularly in this age group. In both the 15–19 and 20–24 years age groups lymphomas were most common. The 5-year relative survival improved for all diagnostic groups, except bone tumours in the older age group, particularly for leukaemia and slightly more for the 20–24 than 15–19 years age group. Teenagers aged 15–19 years and living in more deprived areas had a significantly lower survival than those in more affluent areas. Conclusions These findings confirm the increased incidence and improved outcome of cancer in teenagers and young adults. Future analyses should investigate trends in bone tumour survival across regions, survival by socioeconomic status and the influence of specialised care on further improvements in survival.

Trends in cancer survival in Spearhead Primary Care Trusts in England,1998–2004

The Spearhead Primary Care Trusts (PCTs) are designated as those areas that face the greatest health challenges in England. They are intended to be the focus of interventions designed to reduce health inequalities, including those for cancer. One- and five-year relative survival estimates for cancer patients diagnosed between 1998 and 2004, and resident in a Spearhead PCT area, have been compared with those in the rest of England to assess the baseline trends in inequalities in cancer survival. Survival is consistently lower for patients resident in Spearhead PCT areas than for those resident in the rest of England, although trends in the difference between Spearhead PCTs and the rest of England suggest that the gap in survival has narrowed for most cancers.

Interpreting international comparisons of cancer survival: The effects of incomplete registration and the presence of death certificate only cases on survival estimates

We have assessed the impact on survival estimates based on cancer registry data of incomplete ascertainment of cancer cases and the presence of cases registered purely from death certificate information (DCO cases). Using data from the Thames and Finnish Cancer Registries we obtained five-year relative survival estimates for 12 cancer sites, excluding DCOs as usual. We then made adjustments to allow for the effects of both the known proportion of DCOs and the estimated proportion of missing cases for each site. In general, adjusting for DCOs led to lower survival estimates, whilst adjusting for incompleteness had the opposite effect. The Finnish data were largely complete and had small proportions of DCOs, and hence the adjustments had little effect on estimated survival. The changes in the Thames estimates were more marked. When performing cohort survival analysis (based on diagnoses between 1990 and 1994), the increases in the survival estimates gained from adjusting for incompleteness were for the most part offset by the decrease produced when adjusting for DCOs. However, when performing period survival analysis based on the period 1997–2001 (when the DCO rate at Thames had fallen by around a half relative to the earlier period), the final estimates (adjusted for both effects) were generally higher than the unadjusted values – thus reducing the apparent difference between the two countries. It is important to take variations in DCO proportion and/or completeness into consideration when comparing survival estimates between different populations.

Cancer survival in a southern African urban population.

This paper provides the first comprehensive population based cancer survival estimates from the African continent. Five-year absolute and relative survival estimates are presented for black and white Zimbabwean patients diagnosed with cancer in Harare, Zimbabwe between the years 1993 and 1997. The survival of black Zimbabwean cancer patients are among the lowest ever reported from population based cancer registries. For most cancer sites, white Zimbabwean patients have much higher survival than black Zimbabweans, except for lung and colorectal cancer, for which the estimates are similarly poor. Race specific comparisons to cancer patients in the United States show that Zimbabwean patients have much lower survival than American cancer patients and that the gap between black Zimbabwean patients and black American patients is broader than between white Zimbabwean and white American patients. Access to and the ability to pay for medical care may be a very important barrier to better survival for the majority of black Zimbabwean patients and the most important cause for the very low cancer survival in this population.

Trends in breast cancer mortality, incidence, and survival, and mammographic screening in Tuscany, Italy.

The study describes breast cancer mortality trends in Tuscany (period 1970-97), comparing Florence with the rest of Tuscany (Florence excluded), and, for Florence, incidence (period 1985-94) and survival (1985-86 versus 1991-92) trends, taking into account the diffusion of screening. Mortality and incidence rates, age-adjusted on the European population, and 95% confidence intervals (95% CI). Five-year relative survival rates and estimates of risk of dying provided by the Cox model. Mammographic screening, started at the beginning of the 1970s in some municipalities, largely involved the Florence area after 1990 (mammograms/years: from 8,000-9,000 to 28,000-29,000, respectively, before and after 1990). In the same period no population-based screenings were ongoing in the rest of Tuscany. A significant mortality drop was observed in Tuscany (-3.7%/year), starting at the beginning of the 1990s and observed for ages < or = 74 (especially ages 40-49: -11.2%/year). The drop was similar in Florence and in the rest of Tuscany. In ages 50-69, incidence, increasing between 1985-87 and 1988-90 (+6.5%), rose sharply in 1991-94 (+17.0%); it was stable in other ages. Local disease increased more markedly in ages 50-69 (globally: +88.3%), but also in other ages (+20-30%). Regional and metastatic cancers decreased. A significantly better 5-year survival was observed among cases diagnosed in 1991-92, persisting after adjustment by extent of disease. Even if the causes of breast cancer mortality trends are not easy to clarify in an observational study. our data suggest that the drop in mortality observed in Tuscany at the beginning of the 1990s could be largely explained by both earlier detection, outside of an organized screening program, and by better treatments. The increase in incidence and the shift in stage distribution that occurred before the enlargement of the screening area and in age groups not involved in the program, supports the role of a 'spontaneous' widespread earlier detection. The better survival of the period 1991-92, only partly explained by the shift in stage at diagnosis, indirectly supports the role of improvement in therapy.