Mortality due to cancer treatment delay: systematic review and meta-analysis.

OBJECTIVE: To quantify the association of cancer treatment delay and mortality for each four week increase in delay to inform cancer treatment pathways. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Published studies in Medline from 1 January 2000 to 10 April 2020. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Curative, neoadjuvant, and adjuvant indications for surgery, systemic treatment, or radiotherapy for cancers of the bladder, breast, colon, rectum, lung, cervix, and head and neck were included. The main outcome measure was the hazard ratio for overall survival for each four week delay for each indication. Delay was measured from diagnosis to first treatment, or from the completion of one treatment to the start of the next. The primary analysis only included high validity studies controlling for major prognostic factors. Hazard ratios were assumed to be log linear in relation to overall survival and were converted to an effect for each four week delay. Pooled effects were estimated using DerSimonian and Laird random effect models. RESULTS: The review included 34 studies for 17 indications (n=1 272 681 patients). No high validity data were found for five of the radiotherapy indications or for cervical cancer surgery. The association between delay and increased mortality was significant (P<0.05) for 13 of 17 indications. Surgery findings were consistent, with a mortality risk for each four week delay of 1.06-1.08 (eg, colectomy 1.06, 95% confidence interval 1.01 to 1.12; breast surgery 1.08, 1.03 to 1.13). Estimates for systemic treatment varied (hazard ratio range 1.01-1.28). Radiotherapy estimates were for radical radiotherapy for head and neck cancer (hazard ratio 1.09, 95% confidence interval 1.05 to 1.14), adjuvant radiotherapy after breast conserving surgery (0.98, 0.88 to 1.09), and cervix cancer adjuvant radiotherapy (1.23, 1.00 to 1.50). A sensitivity analysis of studies that had been excluded because of lack of information on comorbidities or functional status did not change the findings. CONCLUSIONS: Cancer treatment delay is a problem in health systems worldwide. The impact of delay on mortality can now be quantified for prioritisation and modelling. Even a four week delay of cancer treatment is associated with increased mortality across surgical, systemic treatment, and radiotherapy indications for seven cancers. Policies focused on minimising system level delays to cancer treatment initiation could improve population level survival outcomes

Estimating the current and future cancer burden in Canada: Methodological framework of the Canadian population attributable risk of cancer (ComPARe) study

Introduction The Canadian Population Attributable Risk of Cancer project aims to quantify the number and proportion of cancer cases incident in Canada, now and projected to 2042, that could be prevented through changes in the prevalence of modifiable exposures associated with cancer. The broad risk factor categories of interest include tobacco, diet, energy imbalance, infectious diseases, hormonal therapies and environmental factors such as air pollution and res

Indoor tanning and skin cancer in Canada: A meta-analysis and attributable burden estimation

Background: Consistent epidemiologic and experimental studies have demonstrated that UV-emitting tanning devices cause melanoma and non-melanoma skin cancer. The purpose of this study was to estimate the relative risk of skin cancer associated with the use of indoor tanning devices relevant to Canada, to estimate the proportion and number of skin cancers in Canada in 2015 that were attributable to indoor tanning, and to explore differences by age and sex. Methods: Skin cancer cases attributable to the use of an indoor tanning devices were estimated using Levin's population attributable risk (PAR) formula. Relative risks for skin cancer subtypes that were relevant to Canada were estimated through meta-analyses and prevalence of indoor tanning was estimated from the 2006 National Sun Survey. Age- and sex-specific melanoma data for 2015 were obtained from the Canadian Cancer Registry, while estimated NMSC incidence data were obtained from the 2015 Canadian Cancer Statistics report. Results: Ever use of indoor tanning devices was associated with relative risks of 1.38 (95% CI 1.22–1.58) for melanoma, 1.39 (1.10–1.76) for basal cell carcinoma (BCC), and 1.49 (1.23–1.80) for squamous cell carcinoma (SCC). Overall, 7.0% of melanomas, 5.2% of BCCs, and 7.5% of SCCs in 2015 were attributable to ever of indoor tanning devices. PARs were higher for women and decreased with age. Conclusion: Indoor tanning contributes to a considerable burden of skin cancer in Canada. Strategies aimed at reducing use should be increased and a total ban or restrictions on use and UV-int

Corrigendum to “Estimates of the current and future burden of melanoma attributable to ultraviolet radiation in Canada” (Preventive Medicine (2019) 122 (81–90), (S009174351930088X), (10.1016/j.ypmed.2019.03.012))

The authors regret that in the third paragraph on page 87, the text should read ‘By reducing the prevalence of indoor tanning, adulthood sunburn, and intentional sunbathing by 50%, 11,980 cases of melanoma could be prevented by 2042.’ The original text erroneously states 12,089. The authors would like to apologise for any inconvenience caused

Corrigendum to “The current and future burden of cancer attributable to modifiable risk factors in Canada: Summary of results” (Preventive Medicine (2019) 122 (140–147), (S0091743519301318), (10.1016/j.ypmed.2019.04.007))

The authors regret that in Table 1 (page 142), footnote ‘a’ should be removed and in Table 2 (page 144), footnote ‘b’ should be removed. In Table 2 on page 144, in the cell corresponding to Human papillomavirus (row) and Cervix (column), the figure 100% should be presented (the cell is currently blank). In Table 3 on page 145, under the column heading ‘Exposure,’ the cells ‘Fruit’ and ‘Vegetable’ should be switched. The authors would like to apologise for any inconvenience caused

The current and future burden of cancer attributable to modifiable risk factors in Canada: Summary of results

Nearly one in two Canadians are expected to be diagnosed with cancer in their lifetime. However, there are opportunities to reduce the impact of modifiable cancer risk factors through well-informed interventions and policies. Since no comprehensive Canadian estimates have been available previously, we estimated the proportion of cancer diagnosed in 2015 and the future burden in 2042 attributable to lifestyle and environmental factors, and infections. Population-based historical estimates of exposure prevalence and their associated risks for each exposure-cancer site pair were obtained to estimate population attributable risks, assuming the exposures were distributed independently and that the risk estimates were multiplicative. We estimated that between 33 and 37% (up to 70,000 cases) of incident cancer cases among adults aged 30 years and over in 2015 were attributable to preventable risk factors. Similar proportions of cancer cases in males (34%) and females (33%) were attributable to these risk factors. Tobacco smoking and a lack of physical activity were associated with the highest proportions of cancer cases. Cancers with the highest number of preventable cases were lung (20,100), colorectal (9800) and female breast (5300) cancer. If current trends in the prevalence of preventable risk factors continue into the future, we project that by 2042 approximately 102,000 incident cancer cases are expected to be attributable to these risk factors per year, which would account for roughly one-third of all incident cancers. Through various risk reduction interventions, policies and public health campaigns, an estimated 10,600 to 39,700 cancer cases per year could be prevented by 2042

Age-standardized cancer-incidence trends in Canada, 1971-2015

BACKGROUND: Although cancer incidence over time is well documented in Canada, trends by birth cohort and age group are less well known. We analyzed age- and sex-standardized incidence trends in Canada for 16 major cancer sites and all cancers combined. METHODS: We obtained nationally representative population-based cancer incidence data in Canada between 1971 and 2015 from the National Cancer Incidence Reporting System (1969-1992) and the Canadian Cancer Registry (1992-2015). We analyzed cancer-incidence trends, reported as annual percent change (APC) for each 10-year group from age 20 to 89 years. We also estimated age-adjusted incidence rate ratios from fitted birth cohort models. RESULTS: Across most age categories, the most recent trends show significant decreases in the incidence of cervical (APC -8.8% to -0.33%), lung (men: -7.42% to -0.36%; women: -6.27% to 1.07%), bladder (women: -4.12% to -0.07%; men: -5.13% to -0.38%) and prostate cancer (-11.11% to -1.11%). Significant increasing trends were observed for kidney, thyroid and uterine cancers. Overall incidence has increased among both sexes younger than 50 years of age, with recent increases in pancreatic cancer among men, breast cancer among women and colorectal cancer among both sexes. From the birth cohort analysis, we observed increasing trends in colorectal, liver and prostate cancers among men; kidney cancer and melanoma among women; and thyroid cancer among both sexes. We observed decreasing trends in cervical and ovarian cancers, and in bladder and lung cancers among men. INTERPRETATION: Cancer incidence is decreasing at many sites targeted by primary-prevention efforts, such as smoking cessation and screening programs. Substanti

Estimates of the current and future burden of lung cancer attributable to PM 2.5 in Canada

The International Agency for Research on Cancer has classified PM 2.

Corrigendum to “Estimates of the current and future burden of lung cancer attributable to residential radon in Canada” [Prev. Med. 122 (2019)100–108](S009174351930129X)(10.1016/j.ypmed.2019.04.005)

The authors regret to inform on three corrections to the relevant paper: 1. In Table 1, there is missing information for Tomasek, 2012. The “Exposure basis” column should have read “Dosimete