Health Systems and Health Economics, School of Public Health, Faculty of Health Sciences, GPO Box U1987, Curtin University, Perth, Western Australia, 6845 Australia; School of Medicine, College of Health & Medicine, University of Tasmania, Churchill Avenue, Hobart, 7005, Tasmania, Australia; Centre for Health Services Research, School of Population and Global Health, Faculty of Medicine, Dentistry and Health Sciences, University of Western Australia, 35 Stirling Highway, Crawley, 6009, Western Australia, Australia.
School of Medicine, College of Health & Medicine, University of Tasmania, Churchill Avenue, Hobart, 7005, Tasmania, Australia; Centre for Health Services Research, School of Population and Global Health, Faculty of Medicine, Dentistry and Health Sciences, University of Western Australia, 35 Stirling Highway, Crawley, 6009, Western Australia, Australia.
Cancer Epidemiol. 2020 Jun;66:101705. doi: 10.1016/j.canep.2020.101705. Epub 2020 Mar 27.
Cancer survival has improved in Western Australia (WA) over recent decades. Loss of life expectancy (LOLE) is a useful measure for assessing cancer survival at a population-level. Some previous studies estimating LOLE have required a minimum follow-up beyond diagnosis to reduce the impact of modelled extrapolation, while others have not. The first aim of this study was to assess the impact of minimum length of follow-up on LOLE estimates for people diagnosed in 2006 with female breast, colorectal, prostate, lung, cervical, combined oesophageal and stomach cancers, and melanoma. Based on these results, the second aim was to assess temporal changes in LOLE for these cancer types for diagnoses between 1982 and 2016.
Person-level linked cancer registry and mortality data were used for invasive primary cancer diagnoses for WA residents aged 15-89 years. The analysis for aim one included cases diagnosed from 1982 to the end of 2006, followed to the end of 2006 (i.e. no minimum follow-up), 2011 (i.e. five years minimum follow-up, assuming survival) or 2016 (i.e. 10 years minimum follow-up). To achieve the second study aim, the diagnostic period was extended to the end of 2016. Life expectancy estimates were obtained after fitting flexible parametric relative survival models. Single-year age and sex-specific death rates were used as a reference to estimate LOLE and proportionate loss of life expectancy.
Temporal changes were not reported for prostate, cervical, oesophageal and stomach cancers or melanoma, due to differences in LOLE estimates by minimum follow-up time, or estimate imprecision. Marked reductions in LOLE were observed for female breast and colorectal cancer. There was minimal absolute reduction for lung cancer, where LOLE remained high.
This study considered the appropriateness of including recent cancer diagnoses when assessing temporal changes in LOLE, finding variation in estimates with differing minimum follow-up or high parameter uncertainty for most included cancer types. Temporal changes in LOLE in-turn reflected changes in the life expectancy of the general population, cancer detection and management. These factors must be considered when estimating and interpreting LOLE estimates.
在过去几十年中，西澳大利亚州（WA）的癌症生存率有所提高。预期寿命损失（LOLE）是评估人群水平癌症生存率的有用指标。一些先前的研究估计 LOLE 需要在诊断后进行至少一段时间的随访，以减少模型外推的影响，而其他研究则没有。本研究的首要目的是评估最小随访时间对 2006 年诊断为女性乳腺癌、结直肠癌、前列腺癌、肺癌、宫颈癌、食管癌和胃癌以及黑色素瘤的人群 LOLE 估计的影响。基于这些结果，第二个目的是评估 1982 年至 2016 年期间这些癌症类型的 LOLE 随时间的变化。
使用 15-89 岁 WA 居民的个体癌症登记和死亡率数据进行侵袭性原发性癌症诊断。第一项研究的分析包括 1982 年至 2006 年底诊断的病例，随访至 2006 年底（即无最小随访）、2011 年（即假设生存五年最小随访）或 2016 年（即 10 年最小随访）。为了实现第二个研究目的，诊断期延长至 2016 年底。在拟合灵活参数相对生存模型后获得预期寿命估计。单一年龄和性别特定死亡率用作参考，以估计 LOLE 和预期寿命的比例损失。
由于最小随访时间的 LOLE 估计值差异或估计值不精确，前列腺癌、宫颈癌、食管癌和胃癌或黑色素瘤未报告时间变化。女性乳腺癌和结直肠癌的 LOLE 明显降低。肺癌的绝对减少最小，LOLE 仍然很高。
本研究考虑了在评估 LOLE 的时间变化时纳入最近的癌症诊断是否合适，发现大多数纳入的癌症类型的估计值随最小随访时间的不同或参数不确定性高而有所不同。LOLE 的时间变化反过来反映了一般人群预期寿命、癌症检测和管理的变化。在估计和解释 LOLE 估计值时，必须考虑这些因素。
