In low- and middle-income countries (LMIC), BCa disproportionately affects young women (23% versus 10% in high-income countries). This is due to misconceptions about the disease, delayed detection, poverty, cultural and religious beliefs, and fear of breast removal.
The goal of screening is to detect preclinical disease in healthy, asymptomatic patients to prevent adverse outcomes, improve survival, and avoid the need for more intensive treatments.
Women in Africa present with BCa at a mean age of around 35- to 45 years, compared to their counterparts living in high-income countries (mean of 45- to 60-years) and present with more advanced disease (in South Africa, 50%-55% of women present with advanced BCa).3
Although mammogram screening from the age of 40 has been shown to save countless lives by reducing the incidence of advanced and inoperable disease with metastases, the uptake in LMICs is low with less than 2.2% of women between the ages of 40- to 69-years having undergone screening.2,3
According to Prof Jennifer Moodley, Director Cancer Research Initiative at the Faculty of Health Sciences at the University of Cape Town, studies have shown that time to a cancer diagnosis may be influenced by several factors including women’s knowledge and awareness of cancer symptoms, whether women see themselves as being at risk for BCa, barriers in the health system, knowledge and attitude of health providers, and psychological, and socio-cultural barriers to healthcare.2
The downside of screening, writes Dr Shirley Lipschitz, considered one of South Africa’s most well- regarded and experienced breast-imaging specialists, is that it can result in overdiagnosis and overtreatment. The American Cancer Society (ACS) and the United States Preventive Services Task Force (USPSTF) consider mortality reduction as the only benefit of screening.4
Some studies show that BCa mortality can be reduced by between 30%–40%, while others show a reduction of 25% decrease in those invited to screening and a 38% reduction in those actually exposed to screening.4
Yet another study showed that mortality decreased by 44% in women aged between 40- to 49-years, 40% in those in the 50–to 59-year age group, 42% in women between 60– to 69-years and 35% in those in the 70–79 age group.4
According to Dr Lipschitz, overdiagnosis and overtreatment of a cancer are perceived as harms of screening.4
The American College of Obstetricians and Gynecologists (ACOG) states that reported rates of overdiagnosis range from 1% to 10% and expose women to unnecessary call backs and biopsies, which incurs great costs, and stress. The USPSTF found that one in eight women diagnosed with BCa with biennial screening from ages 50- to 75-years will be overdiagnosed.5
Furthermore, state the body, for every woman who avoids a death from BCa through screening, two to three women will be treated unnecessarily. Overtreatment, are in part, related to the management of ductal carcinoma in situ.5
According to Dr Lipschitz, improved technology, especially with digital breast tomosynthesis, will enable more screening detected cancers with less call backs and biopsies.3
Guideline screening recommendations
The goal of screening is to detect preclinical disease in healthy, asymptomatic patients to prevent adverse outcomes, improve survival, and avoid the need for more intensive treatments.5
Breast self-examination, breast self-awareness, clinical breast examination, and mammography all have been used alone or in combination to screen for BCa.5
The ACOG recommends regular screening mammography annually or biennially, starting at age 40 years in women at ‘average’ (see box 1) risk of BCa. The USPSTF recommends biennial screening from the age of 50.5
The ACS recommends screening from the age of 40- to 45-years and stopping if life expectancy is >10-years. The ACS recommends yearly screening for women between the ages of 40- and 54-years, and as an ‘option’ for women >55-years.5
The European Commission Initiative on Breast Cancer recommends mammography for women aged 50- to 69-years and with conditional recommendations for women in younger and older age groups.6
The European Society of Medical Oncology (ESMO) recommends regular (annual or biennial) mammography in women aged 50- to 69-years. Regular mammography may also be done for women aged 40- to 49-years and 70- to 74-years, although the evidence for benefit is less well established.6
In women with a strong familial history of BCa, with or without proven BRCA mutations, annual magnetic resonance imaging and annual mammography (concomitant or alternating) are recommended.6
The main focus of the South African clinical guidelines for BCa control and management, is to promote early detection and treatment. The guidelines state that all women irrespective of the reason for the visit to a public healthcare facility should receive provider initiated screening clinical breast examination.7
The examination should be done systematically, followed by the recording of the results. If any abnormality is detected irrespective of the severity, that woman should immediately be given a referral letter detailing the findings to the regional breast unit.7
The guidelines recommends annual mammography in women at high risk (>30%+ lifetime risk [see box 2]) of BCa from the age of 40 (or five years before the age at which a close relative was diagnosed if this calculated age is earlier than 40 years). Ultrasonography can be used for diagnostic follow-up of an abnormality seen on screening mammography. Furthermore, the guidelines recommend that screening should stop at age 70.7
The Radiological Society of South Africa and Breast Imaging Society of South Africa recommend annual screening from 40 to 70 and regular self- and clinical breast examination (CBE).4
How can we improve BCa detection?
Although BCa survival rates have increased in most developed countries, sub-Saharan Africa has the worst mortality-to-incidence ratios globally. This is partly due to the fact that 80% of women in the region present with advanced BCa as mentioned above.8
IN DEVELOPED COUNTRIES
Systemic mammography is accepted as the gold standard for effective screening, but in resource-limited setting, mammography is not considered cost effected and it is recommended that early detection focus on downstaging through improved BCa awareness.8
According to Lince-Deroche et al, lower-cost methods of breast disease detection, which are easily available, include breast self-examination, and a CBE performed by a healthcare provider [see box 3]).9
Lince-Deroche et al recommend the following to improve BCa detection in South Africa:9
- Incorporate breast-health education and awareness-raising, the early signs of BCa, and breast self-examination into existing health-education and outreach activities
- Increase the number of specialist breast centres nationwide and ensure that they are staffed with multi-disciplinary teams
- As a first step towards population-level screening, re-train primary healthcare nurses on how to perform CBE and begin screening of asymptomatic women above 35 years of age (in addition to offering screening for all symptomatic women)
- Strengthen existing referral systems, including through facilitated patient-transport systems
- Maximise the use of mammography and ultrasound for diagnosis by ensuring that the machines are placed in specialist breast centres with trained personnel
- Increase support for and links to patient advocates and counsellors in communities and within specialist breast centres to ensure comprehensive, full-spectrum care
- Establish strong monitoring and evaluation systems to track access to and utilisation of screening, diagnostic and treatment services nationwide
- Support and lead clinical, social, and economic research on BCa and breast-disease management in the country in order to address the current dearth of available information.
Conclusion
Finestone et al developed a model that forecasts the incidence of five of the most commonly diagnosed cancers in South Africa. The aim of the model is to estimate the true underlying burden of cancer, as opposed to diagnosed cases only.10
The team found that the incidence of all cancers has been increasing over time. In South Africa, the total number of cases almost doubled between 2019 and 2030 (about 62 000 to 121 000 incident cases). This is a result of increases in the age specific incidence rate of cancer, as well as the growth and ageing of the South African population.10
This highlights the need for increases in resources available for cancer services, as well as rapid implementation of cancer prevention strategies, to reduce the number of future cancer cases, and thereby reduce the burden on the health system, concluded Finestone et al.10
