Crude probability of death for cancer patients by spread of disease in New South Wales, Australia 1985 to 2014

Prevalence of comorbidities and their impact on survival among older adults with the five most common cancers in Taiwan: a population study

Because of the cancer incidence increase and population aging in Taiwan, we aimed to assess the cancer prevalence, to summarize the comorbidities of older patients with the five most common cancers (i.e., breast, colorectal, liver, lung, and oral), and to develop a Taiwan cancer comorbidity index (TCCI) for studying their actual prognosis. The linkage of the Taiwan Cancer Registry, Cause of Death Database, and National Health Insurance Research Database was used. We followed the standard statistical learning steps to obtain a survival model with good discriminatory accuracy in predicting death due to noncancer causes, from which we obtained the TCCI and defined comorbidity levels. We reported the actual prognosis by age, stage, and comorbidity level. In Taiwan, cancer prevalence nearly doubled in 2004-2014, and comorbidities were common among older patients. Stage was the major predictor of patients' actual prognoses. For localized and regional breast, colorectal, and oral cancers, comorbidities correlated with noncancer-related deaths. Compared with the US, the chances of dying from comorbidities in Taiwan were lower and the chances of dying from cancer were higher for breast, colorectal, and male lung cancers. These actual prognoses could help clinicians and patients in treatment decision-making and help policymakers in resource planning.

Quantifying the number of deaths among Aboriginal and Torres Strait Islander cancer patients that could be avoided by removing survival inequalities, Australia 2005–2016

Background

While Aboriginal and Torres Strait Islander peoples have poorer cancer survival than other Australians, absolute measures of survival disparities are lacking. This study quantified crude probabilities of deaths from cancer and other causes and estimated the number of avoidable deaths for Aboriginal and Torres Strait Islanders if these survival disparities were removed.

Methods

Flexible parametric relative survival models were used to estimate reported measures for a population-based cohort of 709,239 Australians (12,830 Aboriginal and Torres Strait Islander peoples), 2005–2016.

Results

Among Aboriginal and Torres Strait Islander peoples, the 5-year crude probability of cancer death was 0.44, while it was 0.07 for other causes of death. These probabilities were 0.07 and 0.03 higher than among other Australians, respectively. Magnitude of these disparities varied by cancer type and ranged for cancer deaths from <0.05 for pancreatic, prostate and uterine cancers to 0.20 for cervical and head and neck cancers. Values for disparity in other causes of death were generally lower. Among an average cohort of Aboriginal and Torres Strait Islander peoples diagnosed per year over the most recent five-year diagnosis period (2012–2016, n = 1,269), approximately 133 deaths within 5 years of diagnosis were potentially avoidable if they had the same overall survival as other Australians, with 94 of these deaths due to cancer. The total number of avoided deaths over the entire study period (2005–2016) was 1,348, with 947 of these deaths due to cancer.

Conclusions

Study findings suggest the need to reduce the prevalence of risk factors prevalence, increase screening participation, and improve early detection, diagnosis and treatment rates to achieve more equitable outcomes for a range of cancer types. Reported measures provide unique insights into the impact of a cancer diagnosis among Aboriginal and Torres Strait Islander peoples from a different perspective to standard relative survival measures.

Quantifying the absolute number of cancer deaths that would be avoided if cancers were diagnosed prior to progressing to distant metastasis, New South Wales, Australia 1985-2014

This study measures the impact of diagnosing cancers early before they metastasise on reducing the burden of cancer death. A cohort of 716,501 people aged 15-89 years diagnosed with a solid cancer in New South Wales, Australia, during 1985-2014 were followed-up to December 2015. Crude probabilities of cancer death by stage at diagnosis were calculated for all solid cancers combined and five individual cancers using flexible parametric relative survival models. These probabilities were used to estimate the number of avoided cancer deaths within 10 years of diagnosis in three 10-year diagnostic periods if all cases with known distant stage were instead diagnosed at an earlier stage. Cancers known to be diagnosed at distant stage comprised ~16% of all solid cancers diagnosed during 2005-2014. Assuming all these cases were instead diagnosed at regional stage, an annual average of 2,064 cancer deaths would have been potentially avoided within 10 years of diagnosis. This equated to ~21% of modelled observed deaths. Alternatively, if half of all known distant cases diagnosed during 2005-2014 were diagnosed as regional and half as localised, the average number of deaths avoided per year would increase to 2,677 (~28%). Estimates varied by diagnostic period, sex, and cancer type, reflecting both the different stage distributions for the cancer types, and the respective survival differences between cancer stages. While prevention is the most effective pillar of cancer control, these findings quantify the potential benefits of diagnosing all cancer types when they are less advanced to reduce the burden of cancer mortality.