By Dr Alan Smith, Specialist in Public Health Medicine, National Screening Service
Before COVID
BreastCheck – The National Breast Screening Programme invites 600,000 women to participate in screening bi-annually where the screening test is a mammogram. As with any population screening programme, the target population, women aged between 50-69 in this case, are presumed well and do not have any symptoms. The term ‘asymptomatic’ is often used to describe such a population.
BreastCheck typically screens about 185,000 women annually and detects approximately 1,100-1,200 screen-detected cancers each year, accounting for approximately 34% of the total number of breast cancers diagnosed in Ireland. The vast majority, two-thirds (66%+) of breast cancers in Ireland are diagnosed in the symptomatic service - that is, women have symptoms that lead them to seek medical attention from either their GP and/or consultant.
Cancers detected through a breast screening programme are usually at an earlier stage at the time of detection and so would generally have a better outcome in terms of mortality and morbidity [1].
During COVID
- In 2020, when the health services came under huge pressure from COVID-19, achieving the balance between the benefits and harms in screening well women - that is, women without any symptoms, became much more complex. Suddenly we were faced with a new infection risk in COVID-19 – particularly in relation to the breast screening demographic, a portion of whom were in the at-risk population category for COVID-19 infection. We also faced a reduction in overall health service capacity and a requirement to meet the needs of urgent and sick patients continuing to present to the health service.
- In Ireland and many other European health systems, decisions were based on assessing who had the greatest medical need and where the health service could have the greatest impact from what were scarce health service resources during COVID-19.
- In the HSE, breast cancer assessments - that is, for women presenting with symptoms, was a priority service at a time when most other services had been either reduced or stopped. Recognising that health services were severely but necessarily constrained, the National Screening Service (NSS) implemented the ethical decision to provide BreastCheck screening radiographers and consultant radiologists to support those women with known symptoms and therefore most at-risk, rather than providing screening mammograms to well and healthy women.
- A temporary redeployment of BreastCheck staff to the symptomatic breast services took place and enabled high-risk patients with symptoms to be seen quickly, with the aim of improving the outcome of any diagnosis during a time when breast health resources were severely constrained. The redeployment also meant that the BreastCheck Units in Dublin, Cork and Galway could be utilised for the assessment of these women rather than having to compete for space in hospitals dominated by COVID-19 infection/patients.
— This cohort of symptomatic women has been shown to have a significantly higher rate of cancer, and more time-dependent diagnosis, than the screened cohort. For example, if mammography is provided to 1,000 healthy women, seven cancers will be detected. If mammography is provided to 1,000 symptomatic women (i.e. they have breast symptoms), 100 cancers will be detected.
— Urgent breast attendances to the HSE Rapid Access Clinics (RACs) fell by 35% in March 2020 and took a further two months to recover. Efforts to increase clinic capacity saw the number of attendances increase above 2019 numbers for the last four months of 2020. By year end, the number of attendees at urgent breast clinics was 98% of 2019 numbers. It would be reasonable to infer from this data that the redeployment of BreastCheck staff contributed to minimising the adverse impact of COVID-19 on referrals to the symptomatic service. - As a result of the COVID-19 pandemic BreastCheck was paused on March 16 until October 31 2020, and again from January to March 2021, resulting in women’s invitations for routine screening being delayed.
— However, women who had already commenced on their BreastCheck screening pathway were prioritised and continued through their assessment and surgery (if required) stages. All other potential participants in BreastCheck were informed about the pause, the likely delay, symptom awareness and the importance of seeking medical advice in such an instance.
After COVID: screening resumes
- With the pauses in the programme, BreastCheck, had lost nearly a year of screening time. This meant that appointments in the screening round (where we invite women for screening once every 2 years) have been delayed by up to a year. This was compounded by the additional infection control measures around COVID-19 in 2021 and 2022. This in effect means Ireland has been screening women every 3 years, temporarily. A 3-yearly screening interval is not unusual. The NHS Breast Screening Programme for example, uses a 3-year interval between screening rounds across England, Wales, Scotland and Northern Ireland.
- To achieve the maximum population benefit from breast screening requires getting back to a 2-yearly invitation and maximising uptake amongst eligible women i.e. not letting any appointment go to waste. There is no single right strategy for achieving programme recovery after COVID-19. BreastCheck set out to return to screening women every 2 years as soon as possible and is on target to achieve this by Q4 2023 with the initial priority focus on maximising uptake, on those waiting longest and on those most likely to come for screening, on the basis that research has indicated that this approach would be best to maximise cancer detection rates [2].
— In addressing programme capacity and maximising uptake the programme is actively recruiting staff, in particular radiography and consultant radiologists - although this is proving to be extremely difficulty given the worldwide shortage of radiographers; it has purchased three new mobile units/vans which are now operational; refitted mobile units to ensure the provision of a safe space for women to be screened; implemented a new text messaging appointment service to ensure every appointment slot is filled; and has been running information campaigns to inform women about breast screening and breast cancer risks.
The need for comprehensive personal protective equipment (PPE), social distancing and other infection-control measures has limited the capacity of the programme to screen women, safely, within the same timeframe as before COVID-19. However, over time BreastCheck has achieved what it now believes to be the maximum invitation rate that is efficient and compatible with a safe and controlled follow-up assessment, and available treatment capacity within the health service. The programme has returned to near normal daily screening numbers. - Our communications activity gives valuable information to women in our target age range to help them understand when they will be called for screening. Through this, BreastCheck aims to empower women to be active participants in their own health; and work together with us to make sure those who have been waiting longest can be seen first. Women in Ireland have listened and supported the programme in this work.
— Information campaigns to let women know when they can expect their next invitation for screening across TV, digital, social and print media
— Informing women when they are due to be invited and what they can do to help us make sure we maximise appointment uptake
— Letting women know key things they can do to help prevent breast cancer, how to be breast aware, and what to do if they have symptoms
— Production of new information for women on breast cancer risks, prevention and early detection, in conjunction with the National Cancer Control Programme.
The consequences
- It is clear that COVID-19 has caused major disruptions to breast cancer screening programmes globally. However, the long-term impact of the COVID-19 pandemic on breast cancer incidence and mortality has yet to be fully realised. It will take some years to measure the actual impact.
- As in other countries, BreastCheck is undertaking a study that over the course of the next few years will start to provide answers to questions in assessing the real-world impact of COVID-19, including:
— Did our strategy through the redeployment of screening staff to the symptomatic service have the effect of saving lives, offsetting any negative effect of the pause in screening?
— Did keeping pathways open for those already on the screening pathway prior to lockdown, help to ensure there were fewer delays for screening patients entering hospital care?
— Do disruptions to organised screening lead to changes in the stage at which cancer is diagnosed and/or excess mortality?
— Do changes (if any) in the stage cancer is diagnosed have any significant effect in outcomes?
[1] Massat NJ, Sasieni PD, Tataru D, et al. Explaining the better prognosis of screening-exposed breast cancers: influence of tumor characteristics and treatment. Cancer Epidemiol Biomarkers Prev 2016; 25: 479–487
[2] Duffy SW, Hudson S, Vulkan D, Duffy TE, Binysh K. Recovery of the breast screening programme following pandemic-related delays: Should we focus on round length or uptake. J Med Screen 1-5;2022