International Cancer Screening Network Research Articles

Comparing Colorectal Cancer Screening Outcomes in the International Cancer Screening Network: A Consortium Proposal

Randomized trials have shown that stool testing for occult blood and flexible sigmoidoscopy reduce colorectal cancer (CRC) incidence and mortality, and based on observational evidence of its effectiveness, colonoscopy is also frequently used as a screening modality.1 Opportunistic and organized CRC screenings are now available in many countries, presenting opportunities for knowledge exchange and data sharing that could improve the delivery of screening and further reduce CRC morbidity and mortality worldwide.

Abstract 65: Early Assessment of the Pandemic Effects on Cancer Screening Services: The International Cancer Screening Network COVID-19 Survey

Abstract Purpose: Screening, when effectively implemented, can decrease the burden of breast, cervical, colorectal and lung cancers. As COVID-19 became a pandemic in March 2020, cancer screening practitioners globally reported the suspension of cancer screening and diagnostic as part of the emergency response. The International Cancer Screening Network (ICSN) implemented a survey to capture the details and consequences of decisions to suspend cancer screening services and understand the global effects of the COVID-19 pandemic on cancer screening. Methods: A 33-question survey was sent out to 882 email addresses to gather general information about the settings and assess the decision-making process that led to cancer screening suspension (or not). Furthermore, information regarding communication with stakeholders and impact on resources and patient follow-up was collected. Quantitative data have been analyzed as general frequencies overall and by setting, while a comment section under each survey item captured more nuanced information. Results: Responses from the 98 participants that completed the full survey (12%) were categorized into 66 individual settings representing 35 countries. Most settings are organized screening programs (82%, n=54), and suspended cancer screening services (91%, n=60) around March 2020 (68%, n=45), guided by a government decision (77%, n=51). Few settings made their decision about whether to suspend services following a preparedness plan (26%, n=17). Professionals were reassigned (62%, n=41) and infrastructure repurposed (53%, n=35) in most places, and 39% (n=26) saw most follow up visits delayed. Conclusion: COVID-19 pandemic has had important effects on cancer screening services worldwide, including the suspension of cancer screening in most settings. Most cancer screening services were not prepared to deal with the scale of the pandemic but have shown great flexibility in supporting the response. This survey will inform the next steps for assessing the longer-term impact of COVID-19 on cancer screening. Funding statement: Funded by the NCI Contract No. HHSN261200800001E75N910D00024, Task Order No. 75N91019F00129 (D.M.P.P.). Citation Format: Douglas M. Puricelli Perin, K. Miriam Elfström, Mireille J. M. Broeders. Early Assessment of the Pandemic Effects on Cancer Screening Services: The International Cancer Screening Network COVID-19 Survey [abstract]. In: Proceedings of the 9th Annual Symposium on Global Cancer Research; Global Cancer Research and Control: Looking Back and Charting a Path Forward; 2021 Mar 10-11. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2021;30(7 Suppl):Abstract nr 65.

Early assessment of the first wave of the COVID-19 pandemic on cancer screening services: The International Cancer Screening Network COVID-19 survey

Screening can decrease the burden of breast, cervical, and colorectal cancers. The COVID-19 pandemic led many countries to suspend cancer screening services as part of their response to the pandemic. The International Cancer Screening Network (ICSN) carried out an online survey to assess the effects of the first wave of the COVID-19 pandemic on cancer screening. A 33-item survey was distributed to 834 email addresses to gather information about settings and assess decision-making processes that led to cancer screening suspension. Information about communication, impact on resources, and patient follow-up was collected. Quantitative data was analyzed as frequencies overall and by setting, while a comment section under each survey item captured nuanced details. Responses were recategorized into 66 settings, representing 35 countries. Most settings suspended cancer screening services (n = 60, 90.9%) in March 2020 (n = 45, 68.2%), guided by a government decision (n = 51, 77.3%). Few settings made the decision whether to suspend services based on a preparedness plan (n = 17, 25.8%). In most settings, professionals were reassigned (n = 41, 62.1%) and infrastructure repurposed (n = 35, 53.0%). The first wave of the COVID-19 pandemic has had profound effects on cancer screening worldwide, including the suspension of services in almost all settings. Most settings were unprepared to deal with the scale of the pandemic but demonstrated flexibility in the response. These results contribute to inform, through experiences and lessons learned, the next steps for the global cancer screening community to further evaluate the impact of COVID-19 and prepare for future disruptions.

Breast cancer screening and overdiagnosis.

Overdiagnosis is a harmful consequence of screening which is particularly challenging to estimate. An unbiased setting to measure overdiagnosis in breast cancer screening requires comparative data from a screened and an unscreened cohort for at least 30 years. Such randomised data will not become available, leaving us with observational data over shorter time periods and outcomes of modelling. This collaborative effort of the International Cancer Screening Network quantified the variation in estimated breast cancer overdiagnosis in organised programmes with evaluation of both observed and simulated data, and presented examples of how modelling can provide additional insights. Reliable observational data, analysed with study design accounting for methodological pitfalls, and modelling studies with different approaches, indicate that overdiagnosis accounts for less than 10% of invasive breast cancer cases in a screening target population of women aged 50 to 69. Estimates above this level are likely to derive from inaccuracies in study design. The widely discrepant estimates of overdiagnosis reported from observational data could substantially be reduced by use of a cohort study design with at least 10 years of follow-up after screening stops. In contexts where concomitant opportunistic screening or gradual implementation of screening occurs, and data on valid comparison groups are not readily available, modelling of screening intervention becomes an advantageous option to obtain reliable estimates of breast cancer overdiagnosis.

Understanding the Value of International Research Networks: An Evaluation of the International Cancer Screening Network of the US National Cancer Institute.

PURPOSEInternational research networks have the potential to accelerate scientific progress via knowledge sharing and collaboration. In 2018, the US National Cancer Institute evaluated the International Cancer Screening Network (ICSN), in operation since 1988.METHODSICSN hosts a biennial scientific meeting and scientific working groups. A survey was fielded to 665 ICSN participants, and a bibliometric analysis was conducted for ICSN publications.RESULTSA total of 243 individuals completed the survey (36.5%). They reported that participating in the ICSN helped advance their knowledge of cancer screening research (75.7%), policy development (56%), and implementation (47.7%). Approximately three-quarters agreed that ICSN facilitated knowledge sharing and networking among researchers and implementers (79.9%) and those working on different continents (74.0%) and cancer sites (73.7%). More than half reported that participating helped them form new collaborations in screening implementation (58.0%) or research (57.6%). Most agreed that ICSN helped to advance screening research and evaluation (75.4%), effective screening practices (71.2%), and screening policies (60.9%). Many reported that participating informed advances in their own research (68.7%) and screening implementation (50.2%) and policies (49.4%) in their settings. Approximately two-thirds agreed that ICSN helped advance career development among current experts (66.6%) and train the next generation (62.2%). Half (51.4%) reported that participating advanced their own careers. The 20 ICSN publications included 75 coauthors. They were cited in 589 publications with more than 2,000 coauthors.CONCLUSIONFindings provide evidence of the influence of ICSN on international knowledge dissemination, collaboration, and advances in cancer screening research, implementation, and policies and highlight the potential value of longstanding international research networks.

Assessing Knowledge Sharing in Cancer Screening Among High-, Middle-, and Low-Income Countries: Insights From the International Cancer Screening Network.

PURPOSEAs the global burden of cancer rises, global knowledge sharing of effective cancer control practices will be critical. The International Cancer Screening Network (ICSN) of the US National Cancer Institute facilitates knowledge sharing to advance cancer screening research and practice. Our analysis assessed perceptions of ICSN’s value and knowledge sharing in cancer screening among participants working in high-income countries (HICs) and low- and middle-income countries (LMICs).METHODSIn 2018, the National Cancer Institute fielded a self-administered, online survey to 665 ICSN participants from both HICs and LMICs.RESULTSTwo hundred forty-three individuals (36.5%) completed the full survey. LMIC participants engaged in more diverse screening activities and had fewer years of experience (13.5% with more than 20 years of experience v 31%; P = .048) in screening and were more interested in cervical cancer (76.9% v 52.6%; P = .002) than HIC participants. However, both groups spent most of their time on research (30.8% LMIC v 36.6% HIC; P = .518) and agreed that the ICSN biennial meeting enabled them to learn from the experiences of both higher-resource (88.2% v 75.7%; P = .122) and lower-resource (61.8% v 68.0%; P = .507) settings. ICSN helped them form new collaborations for research and implementation (55.1% v 58.2%; P = .063); informed advances in research/evaluation (71.4% v 68.0%; P = .695), implementation (59.2% v 47.9%; P = .259), and policies in their settings (55.1% v 48.0%; P = .425); and provided the opportunity to contribute their knowledge and expertise to assist others (67.3% v 71.1%; P = .695).CONCLUSIONFindings suggest that HIC and LMIC participants benefit from knowledge sharing at ICSN meetings although their interests, backgrounds, and needs differ. This points to the importance of international research networks that are inclusive of HIC and LMIC participants in cancer control to advance knowledge and effective practices globally.

Low-grade screen-detected ductal carcinoma in situ progresses more slowly than high-grade lesions: evidence from an international multi-centre study.

Nuclear grade is an important indicator of the biological behaviour of ductal carcinoma in situ (DCIS). De-escalation of treatment has been suggested for low-grade DCIS. Our aim is to estimate the relative rate of progression of DCIS by nuclear grade by analysing the distribution of nuclear grade by detection at initial or subsequent screening. We asked International Cancer Screening Network sites to complete, based on their screening and clinical databases, an aggregated data file on DCIS detection, diagnosis and treatment. Eleven screening programs reported 5068 screen-detected pure DCIS in nearly 7 million screening tests in women 50-69years of age. For all programs combined, low-grade DCIS were 20.1% (range 11.4-31.8%) of graded DCIS, intermediate grade 31.0% and high grade 48.9%. Detection rates decreased more steeply from initial to subsequent screening in low compared to high-grade DCIS: the ratios of subsequent to initial detection rates were 0.39 for low grade, 0.51 for intermediate grade, and 0.75 for high grade (p < 0.001). These results suggest that the duration of the preclinical detectable phase is longer for low than for high-grade DCIS. The findings from this large multi-centre, international study emphasize that the management of low-grade DCIS should be carefully scrutinized in order to minimize overtreatment of screen-detected slow-growing or indolent lesions. The high variation by site in the proportion of low grade suggests that further pathology standardization and training would be beneficial.

Imagining the Future of the International Cancer Screening Network: Responding to Needs and Engagement in Cancer Screening Globally

Background: Over the past three decades, much evidence has been generated in high-income countries (HIC) for effective implementation of cervical, breast and colorectal cancer screening programs and their contribution to reducing mortality. However, translation of cancer screening programs to low- and middle-income countries (LMIC) continues to be a challenge. For 30 years, the US National Cancer Institute's International Cancer Screening Network (ICSN) has gathered cancer screening researchers, implementers and evaluators at the ICSN biennial scientific meeting, provided expert assistance and facilitated working groups that advance research on cancer screening, via standardization of definitions, metrics, and measures, and cross-national comparative studies. For many years, this group has been comprised largely of participants from HICs, with limited participation by individuals from LMICs. However, in recent years, cancer screening has been adopted in an increasing number of LMICs. There is now a critical need to understand how to translate cancer screening delivery, program implementation, documentation, and research to LMICs. Aim: To gather insights from ICSN participants on the translatability of cancer screening knowledge between high and low-resource settings to advance the field of cancer screening globally. Methods: In 2018, ICSN conducted an evaluation research study to assess the outcomes and impacts of the ICSN to date and inform future ICSN activities, including engagement of individuals working in LMICs. Data collection consisted of a survey to our listserv, which has 666 subscribers. Results: There were 266 network members who responded to the survey, including 244 advanced who completed the full survey. The majority (58.7%) have been working in the field of cancer screening for 15 or fewer years, although 27.8% have 20 or more years of experience. Most respondents work in government agencies (32.7%) and academic institutions (37.2%), and dedicate most of their time to conducting cancer screening research. ICSN members predominantly work in organized cancer screening programs (72.6%). In addition, 80.5% work primarily in HICs and 10.9% in upper middle-income countries. Of those who attended the 2017 ICSN biennial meeting (56.1%), 78.8% agreed that it enabled them to learn from cancer screening in higher resource settings while 66.4% agreed that it enabled them to learn from cancer screening in lower resource settings. Conclusion: With 30 years of experience facilitating the advancement of cancer screening research, implementation and evaluation in HICs, the ICSN has many lessons to offer to countries that are considering establishing cancer screening programs. Findings suggest the relevance of ICSN activities to advancing cancer screening in both HICs and LMICs. ICSN is currently engaged in and developing additional approaches to advance cancer screening in LMICs, including technical assistance, workshops, and regional meetings.

43: DESIGNING EVIDENCE BASED RISK ASSESSMENT SYSTEM FOR CANCER SCREENING AS AN APPLICABLE APPROACH FOR THE ESTIMATING OF TREATMENT ROADMAP

Background and aims:Prevention of cancer and risk assessment activity is highly information – intensively task, yet health care providers don't have appropriate technologies available to access, manage and interpret varied...

Designing clinical and genetic guidelines of colorectal cancer screening as an effective roadmap for risk management.

We aimed to present clinical and genetic guidelines of colorectal cancer screening for risk assessment of populations at risk. National guidelines can be used as a guide for choosing the method of screening for each individual. These guidelines facilitate decision making and support the delivery of cancer screening service. In the first step, a comparative study was performed by using secondary data extracted from the literature review. Three countries (Canada, Australia and United States) were selected from 25 countries that are member in the International Cancer Screening Network (ICSN). The second step of study was qualitative survey. The study was based on the grounded theory approach. Study tool was semi-structured interview. Interviewing involves asking questions and getting answers from participants. 22 expert's perspectives about guidelines of colorectal cancer screening were surveyed. Screening program of selected countries was compared. Countries were surveyed by number of risk groups and subgroups, criteria for risk assessment, beginning age, recommendations, screening approaches and intervals. Australia and United States have three risk groups and Canada has two risk groups. Four risk groups were defined in the national guideline, including high risk, increased risk, average and low risk group. The high risk group comprises of 8 subgroups, increased risk group comprises of 3 subgroups and average risk group contain 4 subgroups. Approved clinical criteria for hereditary syndromes and the roadmap of genetic and pathologic survey were designed. Guidelines and pathways have a vital role in the quality improvement of CRC screening program. National guidelines were refined according to the environmental and genetic criteria of colorectal cancer in Iran. These guidelines provide evidence-based recommendations by risk groups. National pathways as a risk assessment tool can evaluate and improve the processes and outcomes of cancer screening in practice. One of the suggestions for future research is the designing expert system for real-time decision making during a clinical interaction.

International variation in management of screen-detected ductal carcinoma in situ of the breast

BackgroundDuctal carcinoma in situ (DCIS) incidence has grown with the implementation of screening and its detection varies across International Cancer Screening Network (ICSN) countries. The aim of this survey is to describe the management of screen-detected DCIS in ICSN countries and to evaluate the potential for treatment related morbidity. MethodsWe sought screen-detected DCIS data from the ICSN countries identified during 2004–2008. We adopted standardised data collection forms and analysis and explored DCIS diagnosis and treatment processes ranging from pre-operative diagnosis to type of surgery and radiotherapy. ResultsTwelve countries contributed data from a total of 15 screening programmes, all from Europe except the United States of America and Japan. Among women aged 50–69years, 7,176,050 screening tests and 5324 screen-detected DCIS were reported. From 21% to 93% of DCIS had a pre-operative diagnosis (PO); 67–90% of DCIS received breast conservation surgery (BCS), and in 41–100% of the cases this was followed by radiotherapy; 6.4–59% received sentinel lymph node biopsy (SLNB) only and 0.8–49% axillary dissection (ALND) with 0.6% (range by programmes 0–8.1%) being node positive. Among BCS patients 35% received SLNB only and 4.8% received ALND. Starting in 2006, PO and SLNB use increased while ALND remained stable. SLNB and ALND were associated with larger size and higher grade DCIS lesions. ConclusionsVariation in DCIS management among screened women is wide and includes lymph node surgery beyond what is currently recommended. This indicates the presence of varying levels of overtreatment and the potential for its reduction.

Variation in detection of ductal carcinoma in situ during screening mammography: A survey within the International Cancer Screening Network

BackgroundThere is concern about detection of ductal carcinoma in situ (DCIS) in screening mammography. DCIS accounts for a substantial proportion of screen-detected lesions but its effect on breast cancer mortality is debated. The International Cancer Screening Network conducted a comparative analysis to determine variation in DCIS detection. Patients and MethodsData were collected during 2004–2008 on number of screening examinations, detected breast cancers, DCIS cases and Globocan 2008 breast cancer incidence rates derived from national or regional cancer registers. We calculated screen-detection rates for breast cancers and DCIS. ResultsData were obtained from 15 screening settings in 12 countries; 7,176,050 screening examinations; 29,605 breast cancers and 5324 DCIS cases. The ratio between highest and lowest breast cancer incidence was 2.88 (95% confidence interval (CI) 2.76–3.00); 2.97 (95% CI 2.51–3.51) for detection of breast cancer; and 3.49 (95% CI 2.70–4.51) for detection of DCIS. ConclusionsConsiderable international variation was found in DCIS detection. This variation could not be fully explained by variation in incidence nor in breast cancer detection rates. It suggests the potential for wide discrepancies in management of DCIS resulting in overtreatment of indolent DCIS or undertreatment of potentially curable disease. Comprehensive cancer registration is needed to monitor DCIS detection. Efforts to understand discrepancies and standardise management may improve care.

Report from the International Cancer Screening Network Biennial Meeting, October 2012

Report from the International Cancer Screening Network Biennial Meeting, October 2012

Toward standardizing and reporting colorectal cancer screening indicators on an international level: The international colorectal cancer screening network

The International Colorectal Cancer Screening Network was established in 2003 to promote best practice in the delivery of organized colorectal cancer screening programs. To facilitate evaluation of such programs, we defined a set of universally applicable colorectal cancer screening measures and indicators. To test the feasibility of data collection, we requested data on these variables and basic program characteristics from 26 organized full programs and 9 pilot programs in 24 countries. The size of the target population for each program varied considerably from a few thousand to 36 million. The majority of programs used fecal occult blood tests for primary screening, with more using guaiac than immunochemical tests. There was wide variation in the ability of screening programs to report the requested measures and in the values reported. In general, pilot programs were more likely to provide screening measure values than were full programs. As expected, detection rates for polyps and neoplasia were substantially higher in programs screening with endoscopy than in those using fecal occult blood tests. It is hoped that the screening measures and indicators, once revised in the light of this survey, will be adopted and used by existing programs and those in the early planning stages, allowing international comparison with the goal of improved colorectal cancer screening quality.

Breast and cervical cancer screening programme implementation in 16 countries

There is a continuing need to monitor and evaluate the impact of organized screening programmes on cancer incidence and mortality. We report results from a programme assessment conducted within the International Cancer Screening Network (ICSN) to understand the characteristics of cervical screening programmes within countries that have established population-based breast cancer screening programmes. In 2007-2008, we asked 26 ICSN country representatives to complete a web-based survey that included questions on breast and cervical cancer screening programmes. We summarized information from 16 countries with both types of organized programmes. In 63% of these countries, the organization of the cervical cancer screening programme was similar to that of the breast cancer screening programme in the same country. There were differences in programme characteristics, including year established (1962-2003 cervical; 1986-2002 breast) and ages covered (15-70+ cervical; 40-75+ breast). Adoption of new screening technologies was evident (44% liquid-based Pap tests; 13% human papillomavirus (HPV)-triage tests cervical; 56% digital mammography breast). There was wide variation in participation rates for both programme types (<4-80% cervical; 12-88% breast), and participation rates tended to be higher for cervical (70-80%) than for breast (60-70%) cancer screening programmes. Eleven ICSN member countries had approved the HPV vaccine and five more were considering its use in their organized programmes. Overall, there were similarities and differences in the organization of breast and cervical cancer screening programmes among ICSN countries. This assessment can assist established and new screening programmes in understanding the organization and structure of cancer screening programmes.

Erratum to: Recording of hormone therapy and breast density in breast screening programs: summary and recommendations of the International Cancer Screening Network

Erratum to: Recording of hormone therapy and breast density in breast screening programs: summary and recommendations of the International Cancer Screening Network

Recording of hormone therapy and breast density in breast screening programs: summary and recommendations of the International Cancer Screening Network

Breast density and the use of hormone therapy (HT) for menopausal symptoms alter the risk of breast cancer and both factors influence screening mammography performance. The International Cancer Screening Network (ICSN) surveyed its 29 member countries and found that few programs record breast density or the use of HT among screening participants. This may affect the ability of programs to assess their effectiveness in reducing breast cancer mortality. Seven countries recorded the use of HT at screening, and some were able to link screening records to individual prescribing records of HT. Eight countries reported recording breast density at screening mammography for some or all women screened. The recommendations of the ICSN for recording information about breast density and HT are presented.