Cancer survival for Aboriginal and Torres Strait Islander Australians: a national study of survival rates and excess mortality

BackgroundNational cancer survival statistics are available for the total Australian population but not Indigenous Australians, although their cancer mortality rates are known to be higher than those of other Australians. We aimed to validate analysis methods and report cancer survival rates for Indigenous Australians as the basis for regular national reporting.MethodsWe used national cancer registrations data to calculate all-cancer and site-specific relative survival for Indigenous Australians (compared with non-Indigenous Australians) diagnosed in 2001-2005. Because of limited availability of Indigenous life tables, we validated and used cause-specific survival (rather than relative survival) for proportional hazards regression to analyze time trends and regional variation in all-cancer survival between 1991 and 2005.ResultsSurvival was lower for Indigenous than non-Indigenous Australians for all cancers combined and for many cancer sites. The excess mortality of Indigenous people with cancer was restricted to the first three years after diagnosis, and greatest in the first year. Survival was lower for rural and remote than urban residents; this disparity was much greater for Indigenous people. Survival improved between 1991 and 2005 for non-Indigenous people (mortality decreased by 28%), but to a much lesser extent for Indigenous people (11%) and only for those in remote areas; cancer survival did not improve for urban Indigenous residents.ConclusionsCancer survival is lower for Indigenous than other Australians, for all cancers combined and many individual cancer sites, although more accurate recording of Indigenous status by cancer registers is required before the extent of this disadvantage can be known with certainty. Cancer care for Indigenous Australians needs to be considerably improved; cancer diagnosis, treatment, and support services need to be redesigned specifically to be accessible and acceptable to Indigenous people

A case-control study of the protective benefit of cervical screening against invasive cervical cancer in NSW women

Objective: To examine the effects of different Pap screening patterns in preventing invasive cervical cancer among women in New South Wales, Australia. Methods: A total of 877 women aged 20–69 years diagnosed with invasive cervical cancer during 2000–2003 were matched with 2,614 controls by month and year of birth. Screening behavior patterns in 4 years preceding the time of cancer diagnosis in the cases were classified into none (no Pap test in the 4 years), ‘irregular’ (1 of the 4 years with Pap test(s)), and ‘regular’ (2 or more of the 4 years with a Pap test), and compared with those in the matched non-cases over the same period. Conditional logistic regression modeling was used to estimate the relative risk, approximated by the odds ratio, of invasive cervical cancer for regular and irregular cervical screening compared with no screening in the previous 4 years, before and after controlling for potential confounders including the first recorded Pap test result in the preceding 6-year reference period. Results Compared with no screening, irregular Pap screening in the 4 years preceding the cancer diagnosis is estimated to reduce the risk of invasive cervical cancer by about 85% (RR = 0.15, 95% CI: 0.120–0.19); regular Pap screening reduces the risk by about 96% (RR = 0.04, 95% CI: 0.03–0.05). After adjusting for the index Pap test result, the relative risks for invasive cervical cancer were 0.19 (95% CI: 0.13–0.27) for irregular screening and 0.07 (95% CI: 0.04–0.10) for regular Pap screening. Conclusions Regular and irregular Pap tests among women aged 20–69 years were highly effective in preventing invasive cancer. At-risk women with no Pap test history should be encouraged to undergo a Pap test every 2 years, but any Pap screening over a 4-year period remains highly protective against future invasive cervical cancer.Baohui Yang, Stephen Morrell, Yeqin Zuo, David Roder, Elizabeth Tracey and Paul Jelf