Revisiting the Calculation for a Novel Measure of Average Lifespan Shortened: Real-World Examples From Cervical and Ovarian Cancers in Alberta, Canada, 2000 - 2020.

In this technical note, we primarily demonstrate the computation of confidence limits for a novel measure of average lifespan shortened (ALSS). We identified women who had died from cervical and ovarian cancer between 2000 and 2020 from the Alberta cancer registry. Years of life lost (YLL) was calculated using the national life tables of Canada. We estimated the ALSS as a ratio of YLL in relation to the expected lifespan. We computed the confidence limits of the measure using various approaches, including the normal distribution, gamma distribution, and bootstrap method. The new ALSS measure shows a modest gain in lifespan of women, particularly women with ovarian cancer, over the study period.

Premature deaths due to head and neck cancers in canada: A nationwide analysis from 1980 to 2010.

OBJECTIVES/HYPOTHESIS: To examine if there has been a reduction in premature mortality due to head and neck cancers and their subtypes in the Canadian population between 1980 and 2010. STUDY DESIGN: Retrospective database review. METHODS: Mortality data for head and neck cancers were obtained from the World Health Organization's mortality database. Years of life lost (YLL) was calculated according to Canadian life tables. A new measure, average lifespan shortened (ALSS), was calculated as a ratio of YLL over the expected lifespan. RESULTS: During the period of interest, decreases in age standardized rates of death adjusted to the World Standard Population were observed mainly among men. The adjusted YLL rates remained unchanged with respect to oral cancers in women, but slightly decreased for oral cancers in men and for laryngeal cancers in both sexes. Our new measure of ALSS showed that in 1980, patients with oral cancers lost an average of 20% of their lifespan, whereas in 2010, men and women still lost approximately 20% and 18%, respectively. Patients with laryngeal cancers lost 18% of their lifespan in both sexes in 1980 and 17% in 2010. The ALSS subanalysis showed that the largest gain of lifespan was observed for cancers of the hypopharynx in men and for cancers of the floor of mouth and nasopharynx in women. CONCLUSIONS: There appears to be modest improvements in premature mortality due to head and neck cancers in Canada over a 30-year period, with the exception of oral cancers in men. Changes in premature mortality varied slightly by cancer subtypes. LEVEL OF EVIDENCE: NA Laryngoscope, 130:911-917, 2020.