Canadian cancer screening disparities: a recent historical perspective

Current and Future Perspectives on Computed Tomography Screening for Lung Cancer: A Roadmap From 2023 to 2027 From the International Association for the Study of Lung Cancer

Low-dose computed tomography (LDCT) screening for lung cancer substantially reduces mortality from lung cancer, as revealed in randomized controlled trials and meta-analyses. This review is based on the ninth CT screening symposium of the International Association for the Study of Lung Cancer, which focuses on the major themes pertinent to the successful global implementation of LDCT screening and develops a strategy to further the implementation of lung cancer screening globally. These recommendations provide a 5-year roadmap to advance the implementation of LDCT screening globally, including the following: (1) establish universal screening program quality indicators; (2) establish evidence-based criteria to identify individuals who have never smoked but are at high-risk of developing lung cancer; (3) develop recommendations for incidentally detected lung nodule tracking and management protocols to complement programmatic lung cancer screening; (4) Integrate artificial intelligence and biomarkers to increase the prediction of malignancy in suspicious CT screen-detected lesions; and (5) standardize high-quality performance artificial intelligence protocols that lead to substantial reductions in costs, resource utilization and radiologist reporting time; (6) personalize CT screening intervals on the basis of an individual's lung cancer risk; (7) develop evidence to support clinical management and cost-effectiveness of other identified abnormalities on a lung cancer screening CT; (8) develop publicly accessible, easy-to-use geospatial tools to plan and monitor equitable access to screening services; and (9) establish a global shared education resource for lung cancer screening CT to ensure high-quality reading and reporting.

Why is the screening rate in lung cancer still low? A seven-country analysis of the factors affecting adoption

Strong evidence of lung cancer screening's effectiveness in mortality reduction, as demonstrated in the National Lung Screening Trial (NLST) in the US and the Dutch-Belgian Randomized Lung Cancer Screening Trial (NELSON), has prompted countries to implement formal lung cancer screening programs. However, adoption rates remain largely low. This study aims to understand how lung cancer screening programs are currently performing. It also identifies the barriers and enablers contributing to adoption of lung cancer screening across 10 case study countries: Canada, China, Croatia, Japan, Poland, South Korea and the United States. Adoption rates vary significantly across studied countries. We find five main factors impacting adoption: (1) political prioritization of lung cancer (2) financial incentives/cost sharing and hidden ancillary costs (3) infrastructure to support provision of screening services (4) awareness around lung cancer screening and risk factors and (5) cultural views and stigma around lung cancer. Although these factors have application across the countries, the weighting of each factor on driving or hindering adoption varies by country. The five areas set out by this research should be factored into policy making and implementation to maximize effectiveness and outreach of lung cancer screening programs.

Addressing Inequity in Spatial Access to Lung Cancer Screening

BACKGROUND

The successful implementation of an equitable lung cancer screening program requires consideration of factors that influence accessibility to screening services.

METHODS

Using lung cancer cases in British Columbia (BC), Canada, as a proxy for a screen-eligible population, spatial access to 36 screening sites was examined using geospatial mapping and vehicle travel time from residential postal code at diagnosis to the nearest site. The impact of urbanization and Statistics Canada's Canadian Index of Multiple Deprivation were examined.

RESULTS

Median travel time to the nearest screening site was 11.7 min (interquartile range 6.2-23.2 min). Urbanization was significantly associated with shorter drive time (p < 0.001). Ninety-nine percent of patients with ≥60 min drive times lived in rural areas. Drive times were associated with sex, ethnocultural composition, situational vulnerability, economic dependency, and residential instability. For example, the percentage of cases with drive times ≥60 min among the least deprived situational vulnerability group was 4.7% versus 44.4% in the most deprived group.

CONCLUSIONS

Populations at risk in rural and remote regions may face more challenges accessing screening services due to increased travel times. Drive times increased with increasing sociodemographic and economic deprivations highlighting groups that may require support to ensure equitable access to lung cancer screening.

Barriers to Screening At-risk Populations in Canada

Cancer screening is invaluable for early detection of disease, including for breast and lung cancer. Through early detection, cancer treatment can be commenced prior to the development of advanced stage disease, significantly reducing morbidity and mortality. However, eligible patients may face barriers when accessing screening services, and some groups may be more disproportionately affected than others. This review aims to describe some of the most prominent barriers that at-risk populations may face when accessing image-based cancer screening services in Canada. Characterizing these barriers would be helpful in determining the best strategies to increase uptake to these screening services and, consequently, improve health equity.

From the patient to the population: Use of genomics for population screening

Genomic medicine is expanding from a focus on diagnosis at the patient level to prevention at the population level given the ongoing under-ascertainment of high-risk and actionable genetic conditions using current strategies, particularly hereditary breast and ovarian cancer (HBOC), Lynch Syndrome (LS) and familial hypercholesterolemia (FH). The availability of large-scale next-generation sequencing strategies and preventive options for these conditions makes it increasingly feasible to screen pre-symptomatic individuals through public health-based approaches, rather than restricting testing to high-risk groups. This raises anew, and with urgency, questions about the limits of screening as well as the moral authority and capacity to screen for genetic conditions at a population level. We aimed to answer some of these critical questions by using the WHO Wilson and Jungner criteria to guide a synthesis of current evidence on population genomic screening for HBOC, LS, and FH.

Socioeconomic inequalities in colorectal cancer incidence in Canada: trends over two decades

PURPOSE

Colorectal cancer is the third most commonly diagnosed cancer in Canada. This study aimed to measure and examine trends in socioeconomic inequalities in the incidence of colorectal cancer in Canada.

METHODS

This study is a time trend ecological study based on Canadian Census Division level data constructed from the Canadian Cancer Registry, Canadian Census of Population, and National Household Survey. We assessed trends in income and education inequalities in colorectal cancer incidence in Canada from 1992 to 2010. The age-standardized Concentration index ([Formula: see text]), which measures inequality across all socioeconomic groups, was used to quantify socioeconomic inequalities in colorectal cancer incidence in Canada.

RESULTS

The average crude colorectal cancer incidence was found to be 61.52 per 100,000 population over the study period, with males having a higher incidence rate than females (males: 66.98; females: 56.25 per 100,000 population). The crude incidence increased over time and varied by province. The age-standardized C indicated a higher concentration of colorectal cancer incidence among lower income and less-educated neighborhoods in Canada. Income and education inequalities increased over time among males.

CONCLUSION

The concentration of colorectal cancer incidence in low socioeconomic neighborhoods in Canada has implications for primary prevention and screening.

Afrocentric screening program for breast, colorectal, and cervical cancer among immigrant patients in Ontario

PROBLEM ADDRESSED

Black and immigrant populations across Canada have lower screening rates than Canadian-born white populations, predisposing them to increased cancer morbidity and mortality. Effective interventions are required to increase cancer screening rates among these populations.

OBJECTIVE OF PROGRAM

To improve breast, colorectal, and cervical cancer screening rates at TAIBU Community Health Centre, which has a mandate to provide primary health care services to the Black and immigrant community in the greater Toronto area.

PROGRAM DESCRIPTION

An Afrocentric quality improvement program was developed and implemented, consisting of provider audits, cancer screening education programs, a patient call-back program, and a mammography promotion day.

CONCLUSION

TAIBU Community Health Centre's continuous quality improvement approach was successful in engaging health care providers and patients to increase cancer screening participation sustainably in a racially and socioeconomically diverse setting. Rates of breast, colorectal, and cervical cancer screening offered to eligible patients increased from 17% to 72%, 18% to 67%, and 59% to 70%, respectively, between 2011 and 2018.

Exploring the influence of rural residence on uptake of organized cancer screening - A systematic review of international literature

Lower screening uptake could impact cancer survival in rural areas. This systematic review sought studies comparing rural/urban uptake of colorectal, cervical and breast cancer screening in high income countries. Relevant studies (n = 50) were identified systematically by searching Medline, EMBASE and CINAHL. Narrative synthesis found that screening uptake for all three cancers was generally lower in rural areas. In meta-analysis, colorectal cancer screening uptake (OR 0.66, 95 % CI = 0.50-0.87, I² = 85 %) was significantly lower for rural dwellers than their urban counterparts. The meta-analysis found no relationship between uptake of breast cancer screening and rural versus urban residency (OR 0.93, 95 % CI = 0.80-1.09, I² = 86 %). However, it is important to note the limitation of the significant statistical heterogeneity found which demonstrates the lack of consistency between the few studies eligible for inclusion in the meta-analyses. Cancer screening uptake is apparently lower for rural dwellers which may contribute to poorer survival. National screening programmes should consider geography in planning.

Examination of Breast Cancer Screening Knowledge, Attitudes, and Beliefs among Syrian Refugee Women in a Western Canadian Province

Background

Women living in the Arab world present low breast cancer screening rates, delayed diagnosis, and higher mortality rates.

Purpose

To further explore the Muslim Syrian refugee women’s breast self-examination (BSE), utilization of clinical breast examination (CBE) and mammography.

Methods

A cross-sectional descriptive exploratory study design was used. The sample consisted of 75 refugee women. Data were collected using Champion’s Health Belief Model Scale, the Cancer Stigma Scale, and the Arab Culture-Specific Barriers to Breast Cancer Questionnaire. Descriptive, Pearson correlation and logistic regression analyses were used to analyze the data.

Results

A minority of women had BSE (32%), CBE (12%) and mammograms (6.7%) anytime during their lifetime. Women’s breast cancer screening (BCS) knowledge ranked at a medium level (M = 10.57, SD = 0.40). Low knowledge score, BSE information, policy opposition, responsibility, barriers to BSE, and seriousness were found to be statistically significant in women’s BSE practice. BSE benefits and religious beliefs significantly predict CBE Age, education, knowledge, responsibility, susceptibility, social barriers, and religious beliefs were statistically significant in women’s mammography use (p < .01).

Conclusions

Participants’ breast cancer screening practices were low. Health beliefs, Arab culture and stigma about cancer affected women’s BCS practices. Faith-based interventions may improve knowledge and practices.

Sociodemographic characteristics of women with invasive cervical cancer in British Columbia, 2004-2013: a descriptive study

BACKGROUND

Although cancer screening has led to reductions in the incidence of invasive cervical cancer (ICC) across Canada, benefits of prevention efforts are not equitably distributed. This study investigated the sociodemographic characteristics of women with ICC in British Columbia compared with the general female population in the province.

METHODS

In this descriptive study, data of individuals 18 years and older diagnosed with ICC between 2004 and 2013 were obtained from the BC Cancer Registry. Self-reported sociodemographic characteristics were derived from standardized health assessment forms (HAFs) completed upon admission in the BC Cancer Registry. Standardized ratios (SRs) were derived by dividing observed and age-adjusted expected counts by ethnicity or race, language, and marital, smoking and urban-rural status. Differences between observed and expected counts were tested using χ² goodness-of-fit tests. General population data were derived from the 2006 Census, 2011 National Household Survey and 2011/12 Canadian Community Health Survey.

RESULTS

Of 1705 total cases of ICC, 1315 were referred to BC Cancer (77.1%). Of those who were referred, 1215 (92.4%) completed HAFs. Among Indigenous women, more cases were observed (n = 85) than expected (n = 39; SR 2.16, 95% confidence interval [CI] 2.15-2.18). Among visible minorities, observed cases (n = 320) were higher than expected (n = 253; 95% CI 1.26-1.26). Elevated SRs were observed among women who self-identified as Korean (SR 1.78, 95% CI 1.76-1.80), Japanese (SR 1.77, 95% CI 1.74-1.79) and Filipino (SR 1.60, 95% CI 1.58-1.62); lower SRs were observed among South Asian women (SR 0.63, 95% CI 0.62-0.63). Elevated SRs were observed among current smokers (SR 1.34, 95% CI 1.33-1.34) and women living in rural-hub (SR 1.29, 95% CI 1.28-1.31) and rural or remote (SR 2.62, 95% CI 2.61-2.64) areas; the SR was lower among married women (SR 0.90, 95% CI 0.90-0.90).

INTERPRETATION

Women who self-identified as visible minorities, Indigenous, current smokers, nonmarried and from rural areas were overrepresented among women with ICC. Efforts are needed to address inequities to ensure all women benefit from cervical cancer prevention.

Screening for the prevention and early detection of cervical cancer: protocol for systematic reviews to inform Canadian recommendations

PURPOSE

To inform recommendations by the Canadian Task Force on Preventive Health Care on screening in primary care for the prevention and early detection of cervical cancer by systematically reviewing evidence of (a) effectiveness; (b) test accuracy; (c) individuals' values and preferences; and (d) strategies aimed at improving screening rates.

METHODS

De novo reviews will be conducted to evaluate effectiveness and to assess values and preferences. For test accuracy and strategies to improve screening rates, we will integrate studies from existing systematic reviews with search updates to the present. Two Cochrane reviews will provide evidence of adverse pregnancy outcomes from the conservative management of cervical intraepithelial neoplasia. We will search Medline, Embase, and Cochrane Central (except for individuals' values and preferences, where Medline, Scopus, and EconLit will be searched) via peer-reviewed search strategies and the reference lists of included studies and reviews. We will search ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. Two reviewers will screen potentially eligible studies and agree on those to include. Data will be extracted by one reviewer with verification by another. Two reviewers will independently assess risk of bias and reach consensus. Where possible and suitable, we will pool studies via meta-analysis. We will compare accuracy data per outcome and per comparison using the Rutter and Gatsonis hierarchical summary receiver operating characteristic model and report relative sensitivities and specificities. Findings on values and preferences will be synthesized using a narrative synthesis approach and thematic analysis, depending on study designs. Two reviewers will appraise the certainty of evidence for all outcomes using GRADE (Grading of Recommendations Assessment, Development and Evaluation) and come to consensus.

DISCUSSION

The publication of guidance on screening in primary care for the prevention and early detection of cervical cancer by the Task Force in 2013 focused on cytology. Since 2013, new studies using human papillomavirus tests for cervical screening have been published that will improve our understanding of screening in primary care settings. This review will inform updated recommendations based on currently available studies and address key evidence gaps noted in our previous review.

Cervical Screening Practices and Outcomes for Young Women in Response to Changed Guidelines in Calgary, Canada, 2007-2016

OBJECTIVE

The aim of the study was to describe temporal trends in screening and outcomes for women, after changes in guidelines in Alberta, Canada, that raised starting age to 21 years, then to 25 years of age, and reduced frequency to 3 yearly.

MATERIALS AND METHODS

Calgary Laboratory Information System data were used to examine screening rates, follow-up procedures, and cancer among women 10-29 years from 2007 to 2016 in the whole population of Calgary. Interrupted time-series analyses were used to assess changes in screening and subsequent diagnostic procedures over the 10-year period.

RESULTS

Annual screening rates dropped by approximately 10% at all ages older than 15 years after the 2009 Alberta cervical cancer screening guidelines, followed by a steady decrease. Further change continued subsequent to minimal apparent effect of the 2013 Canadian Task Force on Preventive Health Care guidelines. The rates of abnormal test results decreased in concert with decreased screening. No increases in cervical intraepithelial neoplasia 1, cervical intraepithelial neoplasia 2/3, or invasive cervical cancer rates were observed after reduced testing.

CONCLUSIONS

The largest decrease in screening and follow-up procedures occurred in the period immediately after implementation of 2009 Alberta screening guidelines. The number of consequent procedures also decreased in proportion to decreased screening, but there was no increase in cancer rates. Starting screening at the age of 25 years and reducing intervals seem to be safe.

Disparities in cervical cancer screening participation in Iran: a cross-sectional analysis of the 2016 nationwide STEPS survey

BACKGROUND

One of the most important concerns in every healthcare system is the elimination of disparities in health service utilization and achievement of health equity. This study aimed to investigate the disparities in cervical cancer screening participation in Iran.

METHODS

A cross-sectional study was conducted using data from the National Non-Communicable Risk Factors Survey in 2016 (STEPs 2016). Data on cervical cancer screening in addition to demographic and socio-economic factors from 15,975 women aged 18 and above were analyzed. The distribution of surveyed women with regard to cervical cancer screening practice was described. Chi square and logistic regression were used to assess the association of demographic and socio-economic factors with cervical cancer screening participation.

RESULTS

Overall, 52.1% of women aged 30-59 years, had undergone cervical cancer screening at least once in their lifetime. Participation rate in cervical cancer screening programs varied between provinces; ranging from 7.6% in Sistan and Baluchestan to 61.2% in Isfahan. Single marital status, illiteracy, being employed, and having no insurance coverage were associated with lower participation. Age and area of residence were insignificant predictors for participating in cervical cancer screening program. Analysis of the cervical cancer uptake rates across the socio-economic levels revealed that the service is less utilised by high income groups.

CONCLUSIONS

Participation in cervical cancer screening program in Iran is not optimal and could be improved. With regard to the distribution of cervical cancer screening practice, social and geographical disparities indicate the need for further research and more comprehensive strategies in order to reduce them.

Genetic testing in families with hereditary colorectal cancer in British Columbia and Yukon: a retrospective cross-sectional analysis

BACKGROUND

Genetic testing in families with hereditary cancer enables identification of people most likely to benefit from intensive screening and preventive measures; however, the uptake of testing in relatives (known as cascade carrier testing) for hereditary colorectal cancer syndromes has been shown to be low. Our objective was to report rates of familial testing for hereditary colorectal cancer syndromes in a publicly funded hereditary cancer clinic in Canada.

METHODS

A cross-sectional retrospective database review was used to determine testing uptake between 1997 and 2016 for families served by the provincial Hereditary Cancer Program for British Columbia and Yukon. Analyses were conducted for genes associated with syndromes with an increased risk for colorectal cancer, including Lynch syndrome (MLH1, MSH2, MSH6, PMS2 and EPCAM) and familial adenomatous polyposis (APC), and for additional moderate- to high-penetrance genes (STK11, TP53, SMAD4, MUTYH, PTEN and CHEK2). Descriptive statistics were used and all analyses were 2-tailed.

RESULTS

The study cohort included 245 index patients, with carrier testing performed in 382 relatives. The mean age at family member testing was 41.2 years, and most (61.0%) of the family members who underwent testing were women. The median time between disclosure of index cases and their family member's results was 8.3 months. Among eligible first-degree relatives, 32.6% (268/821) underwent testing in BC. Of 67 cancer diagnoses in family members, most (62.7%) occurred before genetic testing.

INTERPRETATION

A substantial proportion of people at risk for hereditary colorectal cancer do not undergo genetic testing. This gap highlights the need to explore barriers to testing and to consider interventions to promote uptake; more aggressive efforts by hereditary cancer programs are needed to reach this highest risk population.

Access to cancer care in northwestern Ontario-a population-based study using administrative data

Background

Despite universal access to health care in Canada, there are disparities relating to social determinants of health that contribute to discrepancies between rural and urban areas in cancer incidence and outcomes. Given that Canada has one of the highest-quality national population-based cancer registry systems in the world and that little information is available about cancer statistics specific to northwestern Ontario, the purpose of the present study was to estimate the percentage of cancer patients without documentation of a specialist consultation (medical or radiation oncology consultation) and to determine factors that affect access to specialist consultation in northwestern Ontario.

Methods

This population-based retrospective study used administrative data obtained through the Ontario Cancer Data Linkage Project. For each index case, a timeline was constructed of all Ontario Health Insurance Plan billing codes and associated service dates, starting with the primary cancer diagnosis and ending with death. Specific factors affecting access to specialist consultation were assessed.

Results

Within the 6-year study period (2010-2016), 2583 index cases were identified. Most (n = 2007, 78%) received a specialist consultation. Factors associated with not receiving a specialist consultation included older age [p < 0.0001; odds ratio (or): 0.29; 95% confidence interval (ci): 0.19 to 0.44] and rural residence (p < 0.0001; or: 0.48; 95% ci: 0.48 to 0.72). Factors associated with receiving a specialist consultation included a longer timeline (p < 0.0001; or: 1.32; 95% ci: 1.19 to 1.46), a diagnosis of breast cancer (p < 0.0001; or: 2.51; 95% ci: 1.43 to 4.42), and a diagnosis of lung cancer (p < 0.0001; or: 1.77; 95% ci: 1.38 to 2.26).

Conclusions

This study is the first to look at care access in northwestern Ontario. The complexity and multidisciplinary nature of cancer care makes the provision of appropriate care a challenge; a one-size-fits-all disease prevention and treatment strategy might not be appropriate.

Beyond Universal Health Care: Barriers to Breast Cancer Screening Participation in Canada

PURPOSE

Despite well-established preventive screening guidelines for breast cancer, screening rates do not meet targets in both the United States and Canada. Although access to preventive care is an important factor toward participation, breast cancer screening rates in Canada vary despite a universal health care system. The objective of this study is to understand features within the Canadian population that potentiate screening disparities through a systematic review of the literature.

METHODS

A search of MEDLINE and Embase was performed to identify relevant studies published from 2005 onward. Titles and abstracts were screened, followed by full-text screening. Inclusion criteria were defined as studies reporting on disparities in image-based screening for breast cancer.

RESULTS

Three hundred twenty-four studies were retrieved, from which 29 studies were selected on the basis of the predetermined inclusion criteria. Population groups identified at risk for low image-based screening participation included those of low socioeconomic status, individuals with comorbidities, new immigrants and refugees, those in remote geographic locations, individuals with intellectual or developmental disabilities, and ethnocultural minorities. Barriers to image-based screening can be improved by targeting measures specific to these at-risk groups at the individual, organization, and policy levels.

CONCLUSIONS

Multiple at-risk population groups exist for preventive cancer screening within a universal health care system. By understanding specific characteristics within these vulnerable populations, effective intervention strategies can be established to improve breast cancer preventive care.

Brain cancer survival in Canada 1996-2008: effects of sociodemographic characteristics

Background

Literature suggests that factors such as rural residence and low socioeconomic status (ses) might contribute to disparities in survival for Canadian cancer patients because of inequities in access to care. However, evidence specific to brain cancer is limited. The present research estimates the effects of rural or urban residence and ses on survival for Canadian patients diagnosed with brain cancer.

Methods

Adults diagnosed with primary malignant brain tumours during 1996-2008 were identified through the Canadian Cancer Registry. Brain tumours were classified using International Classification of Diseases for Oncology (3rd edition) site and histology codes. Hazard ratios (hrs) and 95% confidence intervals (cis) were estimated using Cox proportional hazards models. Events were restricted to individuals whose underlying cause of death was cancer-related. Postal codes were used to match patient records with Statistics Canada data for rural or urban residence and neighbourhood income as a surrogate measure of ses.

Results

Of 25,700 patients included in the analysis, 78% died during the study period, 21% lived in rural areas, and 19% were in the lowest income group. A modest variation in survival by rural compared with urban residence was observed for patients with glioblastoma (first 5 weeks after diagnosis hr: 0.86; 95% ci: 0.79 to 0.99) and oligoastrocytoma (first 3 years after diagnosis hr: 1.41; 95% ci: 1.03 to 1.93). Small effects of low compared with high income were seen for patients with glioblastoma (first 1.5 years after diagnosis hr: 1.15; 95% ci: 1.08 to 1.22) and diffuse astrocytoma (first 6 months after diagnosis hr: 1.17; 95% ci: 1.00 to 1.36).

Conclusions

Our analysis did not yield evidence of strong effects of rural compared with urban residence or ses strata on survival in brain cancer. However, some variation in survival for patients with specific histologies warrants further research into the mechanisms by which rural or urban residence and income stratum influences survival.

Testing e-mail content to encourage physicians to access an audit and feedback tool: a factorial randomized experiment

Background

In Ontario, an online audit and feedback tool that provides primary care physicians with detailed information about patients who are overdue for cancer screening is underused. In the present study, we aimed to examine the effect of messages operationalizing 3 behaviour change techniques on access to the audit and feedback tool and on cancer screening rates.

Methods

During May-September 2017, a pragmatic 2×2×2 factorial experiment tested 3 behaviour change techniques: anticipated regret, material incentive, and problem-solving. Outcomes were assessed using routinely collected administrative data. A qualitative process evaluation explored how and why the e-mail messages did or did not support Screening Activity Report access.

Results

Of 5449 primary care physicians randomly allocated to 1 of 8 e-mail messages, fewer than half opened the messages and fewer than 1 in 10 clicked through the messages. Messages with problem-solving content were associated with a 12.9% relative reduction in access to the tool (risk ratio: 0.871; 95% confidence interval: 0.791 to 0.958; p = 0.005), but a 0.3% increase in cervical cancer screening (rate ratio: 1.003; 95% confidence interval: 1.001 to 1.006; p = 0.003). If true, that association would represent 7568 more patients being screened. No other significant effects were observed.

Conclusions

For audit and feedback to work, recipients must engage with the data; for e-mail messages to prompt activity, recipients must open and review the message content. This large factorial experiment demonstrated that small changes in the content of such e-mail messages might influence clinical behaviour. Future research should focus on strategies to make cancer screening more user-centred.

Rural–urban disparities in colorectal cancer screening among military service members and Veterans

Introduction: Little is known about rural–urban disparities in colorectal cancer (CRC) screening rates among the military service member and Veteran (SMV) population in the United States. Given that health care access is a challenge in rural areas, we sought to determine whether rural-dwelling Veterans were less likely to be screened for CRC than urban-dwelling Veterans. Methods: Secondary data for this cross-sectional study were retrieved from the 2016 Behavioral Risk Factor Surveillance System for a national sample of non-institutionalized SMVs ( N = 63,919). The influence of rurality on CRC screening among SMVs was determined using maximum likelihood multiple logistic regression. Results: After controlling for relevant covariates, rurality was independently associated with decreased likelihood of meeting guidelines for CRC screening among SMVs (odds ratio = 0.83, 95% confidence interval, 0.76–0.90). Discussion: Innovative interventions for CRC screening should target SMVs in rural areas because doing so may lower mortality from CRC.

Differences in colorectal cancer screening rates across income strata by levels of urbanization: results from the Canadian Community Health Survey (2013/2014)

OBJECTIVE

Canadian colorectal cancer screening rates differ across income strata. In the United States, disparities across income strata worsen in rural areas. In Canada, differences in screening across income strata have not been explored by levels of urbanization. This project aimed to estimate up-to-date colorectal cancer (UTD-CRC) screening across income strata by levels of urbanization.

METHODS

Data from the Canadian Community Health Survey (2013/2014) were used to estimate the prevalence of UTD-CRC screening by income quintiles for Canadians aged 50-74 years. UTD-CRC screening was defined as fecal occult blood testing within 2 years or colonoscopy/sigmoidoscopy within 10 years before the survey. Levels of urbanization were defined per Statistics Canada Metropolitan Influenced Zone classifications. Weighted proportions of UTD-CRC screening were calculated and logistic regression was used to assess the effect of income by levels of urbanization.

RESULTS

Self-reported UTD-CRC screening prevalence among Canadians was 52.0%. UTD-CRC screening rates by income ranged from 47.8% (Q1-low) to 54.0% (Q5-high). Across all levels of urbanization, higher income was associated with increased odds of UTD-CRC screening compared to the lowest income quintile (Urban-OR_Q5 = 1.49, 95% CI 1.17-1.89; Rural-OR_Q5 = 1.42, 95% CI 1.02-1.99; Remote-OR_Q5 = 1.54, 95% CI 1.02-2.31). Higher education (OR_{post-secondary} = 1.30, 95% CI 1.14-1.49), increasing age (OR_70-74 = 2.88, 95% CI 2.39-3.47), and not identifying as an immigrant (OR = 1.45, 95% CI 1.19-1.75) were associated with an increased odds of UTD-CRC screening.

DISCUSSION

Half of Canadians report UTD-CRC screening but across levels of urbanization, higher income was associated with higher screening rates. Efforts are needed to understand and address inequities, particularly among low-income populations.

Predictors of non-adherence to colorectal cancer screening among immigrants to Ontario, Canada: a population-based study

Though colorectal cancer (CRC) screening rates have increased over time in Ontario, Canada, immigrants continue to have lower rates of screening. This study examines the association between non-adherence to CRC screening and immigration, socio-demographic, healthcare utilization, and primary care physician characteristics among immigrants to Ontario. This is a population-based retrospective cross-sectional study that uses healthcare administrative databases housed at the Institute for Clinical Evaluative Sciences. Our cohort comprised immigrants aged 60 to 74 years who lived in Ontario on March 31, 2015 and who had been eligible for the Ontario Health Insurance Plan for at least 10 years. The outcome was lack of adherence to CRC screening with any modality (fecal occult blood test, flexible sigmoidoscopy, colonoscopy) on March 31, 2015. Our cohort contained 182,949 immigrants. Overall 70,134 (38%) individuals were not adherent to screening. Risk of non-adherence to CRC screening was higher among immigrants who were from low (adjusted relative risk [ARR] 1.35, 95%CI 1.28-1.42) or low-middle (ARR 1.27, 95%CI 1.24-1.30, population-attributable risk [PAR] 9.8%) income countries and refugees (ARR 1.09, 95%CI 1.06-1.11). Compared to those from the United States, Australia, and New Zealand, immigrants from most other world regions, particularly Eastern Europe and Central Asia (ARR 1.28, 95%CI 1.21-1.37), had higher risks of non-adherence. Non-immigration factors such as low healthcare use and lack of primary care enrolment also increased the risk of non-adherence to screening. These findings can be used to inform future efforts to improve uptake of CRC screening among immigrant groups.

Inequities in genetic testing for hereditary breast cancer: implications for public health practice

The Ontario Breast Screening Program for women with a genetic predisposition to breast cancer is one of the first international models of a government-funded public health service that offers systematic genetic screening to women at a high risk of breast cancer. However, since the implementation of the program in 2011, enrolment rates have been lower than anticipated. Whilst there may be several reasons for this to happen, it does call into consideration the 'inverse equity law', whereby the more advantaged in society are the first to participate and benefit from universal health services. An outcome of this phenomenon is an increase in the health divide between those that are at a social advantage versus those that are not. Using an intersectionality lens, this paper explores the role of the social determinants of health and social identity in creating possible barriers in the access to genetic screening for hereditary breast cancer, and the implications for public health practice in recognising and ameliorating these differences.

Cancer mortality in Yukon 1999-2013: elevated mortality rates and a unique cancer profile

Background: Although cancer is the leading cause of death in Canada, cancer in the North has been incompletely described.

Objective: To determine cancer mortality rates in the Yukon Territory, compare them with Canadian rates, and identify major causes of cancer mortality.

Design: The Yukon Vital Statistics Registry provided all cancer deaths for Yukon residents between 1999-2013. Age-standardised mortality rates (ASMRs) were calculated using direct standardisation and compared with Canadian rates. Standardised mortality ratios (SMRs) were calculated using indirect standardisation relative to age-specific rates from Canada, British Columbia (BC), and three sub-provincial BC administrative health regions : Interior Health (IH), Northern Health (NH) and Vancouver Coastal Health (VCH). Trends in smoothed ASMRs were examined with graphical methods.

Results: Yukon’s all-cancer ASMRs were elevated compared with national and provincial rates for the entire period. Disparities were greatest compared with the urban VCH: prostate (SMR_VCH=246.3, 95% CI 140.9–351.6), female lung (SMR_VCH=221.2, 95% CI 154.3–288.1), female breast (SMR_VCH=169.0 95% CI, 101.4–236.7), and total colorectal (SMR_VCH=149.3, 95% CI 101.8–196.8) cancers were significantly elevated. Total stomach cancer mortality was significantly elevated compared with all comparators.

Conclusions: Yukon cancer mortality rates were elevated compared with national, provincial, urban, and southern-rural jurisdictions. More research is required to elucidate these differences.

Enhancing access to cervical and colorectal cancer screening for women in rural and remote northern Alberta: a pilot study

BACKGROUND

Women in rural and remote northern Alberta access breast cancer screening through a mobile mammogram program (Screen Test). The Enhanced Access to Cervical and Colorectal Cancer Screening (EACS) project was a 2-year pilot that aimed to integrate cervical and colorectal cancer screening with the Screen Test program. This study compares cervical and colorectal cancer screening uptake among women screened through the pilot (Screen Test-EACS) versus Screen Test.

METHODS

Screen Test-EACS was offered between 2013 and 2015 in selected rural and remote sites, with a focus on hard-to-reach women living in First Nations, Métis and Hutterite communities. Participation in cervical and colorectal cancer screening was analyzed for Screen Test and Screen Test-EACS participants 6 weeks before clients received their mammogram and then again 3 months after.

RESULTS

A total of 8390 and 1312 women participated in Screen Test and Screen Test-EACS, respectively. Screen Test-EACS significantly increased uptake of cervical (10.1% v. 27.5%) and colorectal (10.9% v. 22.5%) cancer screening, increasing the prevalence of women up to date with screening from 52.5% to 62.9% for cervical cancer screening and from 37.3% to 48.7% for colorectal cancer screening.

INTERPRETATION

Screen Test-EACS increased participation in and the overall prevalence of cervical and colorectal cancer screening among hard-to-reach clients in northern Alberta, probably through removal of barriers to access and increased awareness. Further research should focus on balancing the benefits of increased participation with the costs and potential risks of over-screening.

Introduction of molecular HPV testing as the primary technology in cervical cancer screening: Acting on evidence to change the current paradigm

Since being introduced in the 1940s, cervical cytology - despite its limitations - has had unequivocal success in reducing cervical cancer burden in many countries. However, we now know that infection with human papillomavirus (HPV) is a necessary cause of cervical cancer and there is overwhelming evidence from large-scale clinical trials, feasibility studies and real-world experience that supports the introduction of molecular testing for HPV as the primary technology in cervical cancer screening (i.e., "HPV primary screening"). While questions remain about the most appropriate age groups for screening, screening interval and triage approach, these should not be considered barriers to implementation. Many countries are in various stages of adopting HPV primary screening, whereas others have not taken any major steps towards introduction of this approach. As a group of clinical experts and researchers in cervical cancer prevention from across Canada, we have jointly authored this comprehensive examination of the evidence to implement HPV primary screening. Our intention is to create a common understanding among policy makers, agencies, clinicians, researchers and other stakeholders about the evidence concerning HPV primary screening to catalyze the adoption of this improved approach to cervical cancer prevention. With the first cohort of vaccinated girls now turning 21, the age when routine screening typically begins, there is increased urgency to introduce HPV primary screening, whose performance may be less adversely affected compared with cervical cytology as a consequence of reduced lesion prevalence post-vaccination.