With 1 in 8 women estimated to be diagnosed with breast cancer during their lifetime, I would be very surprised if you or someone you know has not been affected by breast cancer (1). Thankfully, the mortality rate of breast cancer is declining worldwide, partly due to early detection (2). This blog aims to raise awareness of the importance of early detection of breast cancer.
What is breast cancer?
Breast cancer refers to the uncontrolled growth and division of abnormal cells within breast tissue (2,3). Over time, a large mass of cells forms, commonly known as a tumour (3). Breast cancer normally begins in the milk ducts of the breast (3). About 15% of all people with breast cancer will have invasive lobular carcinoma, whereby cancer starts in the lobules of the breast before spreading to the surrounding tissue (3). Key mechanisms that contribute to disease are increased expression of hormone receptors, impaired suppression of tumour genes, and immune cell tolerance to cancer cells (2).
Understandably, when we think about cancer, we are often quite pessimistic. However, around 76% of people with breast cancer will survive for 10 or more years (4). What is the key to an increased chance of survival? The earlier the breast cancer is detected the more treatable it is (5). This is why breast cancer screening is free for all women aged 50–70 years in the UK (6). Mammograms are an extremely useful tool for early diagnosis of breast cancer, and only require 30 minutes (7). Did you know mammograms have reduced mortality from breast cancer by 20% (2)? This is because treatments are most effective in the early stages of cancer (2).
Diagnosis is confirmed by a positive mammogram, clinical examination, and a needle biopsy (2,8). The biopsy helps to determine the levels of three hormone receptors: oestrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) (2). The results are used to determine which of the four subtypes (ER-positive, PR-positive, triple-positive, triple-negative) of breast cancer is present (2). It is important to know the subtype of cancer as this affects treatment and prognosis. For example, triple-negative breast cancer (TNBC) is extremely fast-growing and invasive, resulting in a poor prognosis (9).
What are the risk factors of breast cancer?
About 10% of breast cancers are inherited and have a strong family history (9). Examples include faulty copies of the BRCA1 or BRCA2 genes (9). If BRCA1 is familiar, it may be because Angelina Jolie bravely told her story about having a double mastectomy to reduce her risk of this aggressive form of breast cancer (10). Another 20% of cases can be prevented by maintaining a healthy weight, being physically active, and reducing alcohol intake (9). Arguably, the largest risk of breast cancer is age; post-menopausal women, normally over 50 years of age, account for 8 out of 10 breast cancer diagnoses (11).
What are the symptoms of breast cancer?
Regardless of age, all women should regularly check their breasts for signs of breast cancer. What are the most common signs you should look out for (12)?
- Lumps or swelling of the breast, upper chest, or armpit
- Changes in breast colour, especially any red or inflamed areas
- Puckering or dimpling of the breast skin
- Inversion or changes to the nipple
- Nipple crusting or discharge
- Any changes in the size or shape of the breast
If you have any new or unusual changes in the breast, it is important to seek medical advice sooner rather than later (5,12).
What treatments are available for breast cancer?
What treatments come to mind when you think of cancer? Most people will think of chemotherapy and radiotherapy. Today, the standard of care for early-stage breast cancer is neoadjuvant therapy (2). What is neoadjuvant therapy? It is a combination of chemotherapy and targeted therapy. Neoadjuvant therapy is favoured for triple-negative and HER2-positive breast cancer due to its highly invasive nature and poor prognosis (2,8). How effective is neoadjuvant therapy in these subtypes of patients? Neoadjuvant therapy can reduce breast cancer recurrence by 30% in TNBC (2). HER2+ breast cancer neoadjuvant therapy, comprising of chemotherapy and an anti‑HER2 targeted inhibitor (trastuzumab), can increase the treatment response rate by 65–70% and increase disease-free survival (2). Immunotherapy is a form of targeted therapy that harnesses the body’s immune system to attack the cancer cells (2,8). It is reserved for those patients who have metastatic cancer or TNBC due to high treatment costs (2,8). For example, pembrolizumab with chemotherapy was found to induce the disappearance of TNBC in 63% of patients (13).
Whilst most of us are familiar with the side effects of chemotherapy and radiation, mainly nausea, fatigue, and hair loss, the side effects of immunotherapy are less well-known (14). Immunotherapy most commonly causes mild flu-like symptoms, nausea, and fatigue (14). However, in rare cases, it can cause severe illnesses such as hepatitis, colitis, and pancreatitis (14).
What effect has COVID-19 had on breast cancer?
It is estimated that 1.5 million fewer women have had breast cancer screening since the COVID-19 pandemic began (5). This is due to the temporary suspension of breast cancer screening in March 2020, and a general apprehension about using healthcare services during the pandemic (5). There is an urgent need for campaigns to reassure eligible women that breast cancer screening is safe during the pandemic (5). A clear action plan is also needed to address the backlog of eligible patients who had appointments delayed or cancelled due to the pandemic (5). These actions are imperative for the early diagnosis, treatment, and survival of millions of women.
What does the future of breast cancer treatment look like?
Cancer Research UK alone provides £24.8 million per year for research into breast cancer. Despite this, the prognosis for advanced-stage breast cancer and for TNBC remains poor (2). African and African American women are more likely to receive a diagnosis of TNBC or metastatic cancer (8). Research for these types of cancer is focused on immunotherapies, targeted therapies, or neoadjuvant therapy (8). A combination of both immunotherapy and targeted therapy is becoming increasingly popular (7). The rationale behind this approach is two-fold. Firstly, immunotherapies will boost the immune system’s ability to kill the cancer cells (8,9). Secondly, the targeted therapies target proteins involved in the spread or metastasis of cancer cells (2,8). In combination, these therapies should be more effective at slowing down and/or killing cancer(8).
What does the National Health Service (NHS) long-term plan aim to do? The plan highlights the importance of early detection and aims to increase the uptake of breast cancer screening as well as introduce new screening technologies (16). To increase the number of patients diagnosed earlier with breast cancer, they aim to take a more personalised approach to diagnosis and to use risk−stratified screening (16). As we learned earlier target therapy is likely to offer the best treatment outcomes for patients (8). The NHS long-term plan recognises this and aims to give patients a more personalised treatment plan (16). Importantly, they want to increase support for all breast cancer patients by providing more Clinical Nurse Specialists (16). These steps will hopefully help to increase early diagnosis, quality of life, and survival of breast cancer patients (16).
Overall, breast cancer is the most common cancer worldwide and screening programmes have reduced the mortality rate by about 20% (2). However, there is an urgent and imperative need to increase the number of women taking part in breast cancer screening programmes (5). It is clear that an increase in research and a more personalised approach to therapy is needed to improve the prognosis in advanced breast cancer and TNBC (2,8). If you only take one thing away from this blog, please remember to regularly check your breasts for signs of breast cancer; it might just save your life!
- Breast cancer in women [Internet]. nhs.uk. 2019 [cited 2022 Jan 17]. Available from: https://www.nhs.uk/conditions/breast-cancer/
- Loibl S, Poortmans P, Morrow M, Denkert C, Curigliano G. Breast cancer. The Lancet. 2021 May 8;397(10286):1750–69.
- What is breast cancer? | Cancer Research UK [Internet]. [cited 2022 Jan 17]. Available from: https://www.cancerresearchuk.org/about-cancer/breast-cancer/about
- Breast cancer statistics [Internet]. Cancer Research UK. [cited 2022 Jan 17]. Available from: https://www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/breast-cancer
- Breast screening and coronavirus: up to 1.5 million fewer women seen by screening services since they restarted [Internet]. Breast Cancer Now. 2021 [cited 2022 Jan 17]. Available from: https://breastcancernow.org/about-us/news-personal-stories/breast-screening-coronavirus-15-million-fewer-women-seen-screening-services-they-restarted
- Breast screening | Breast cancer | Cancer Research UK [Internet]. [cited 2022 Jan 17]. Available from: https://www.cancerresearchuk.org/about-cancer/breast-cancer/getting-diagnosed/screening/breast-screening
- What happens at your breast screening appointment [Internet]. nhs.uk. 2021 [cited 2022 Jan 17]. Available from: https://www.nhs.uk/conditions/breast-screening-mammogram/what-happens-at-your-breast-screening-appointment/
- Harbeck N, Penault-Llorca F, Cortes J, Gnant M, Houssami N, Poortmans P, et al. Breast cancer. Nat Rev Dis Primer. 2019 Sep 23;5(1):1–31.
- Breast Cancer Hormone Receptor Status Estrogen Receptor [Internet]. [cited 2022 Jan 17]. Available from: https://www.cancer.org/cancer/breast-cancer/understanding-a-breast-cancer-diagnosis/breast-cancer-hormone-receptor-status.html
- Angelina Jolie, inherited breast cancer and the BRCA1 gene [Internet]. Cancer Research UK – Cancer News. 2013 [cited 2022 Jan 17]. Available from: https://news.cancerresearchuk.org/2013/05/14/angelina-jolie-inherited-breast-cancer-and-the-brca1-gene/
- Breast cancer in women – Causes [Internet]. nhs.uk. 2017 [cited 2022 Jan 17]. Available from: https://www.nhs.uk/conditions/breast-cancer/causes/
- Breast Cancer Symptoms & Signs [Internet]. Breast Cancer Now. 2015 [cited 2022 Jan 17]. Available from: https://breastcancernow.org/information-support/have-i-got-breast-cancer/signs-symptoms-breast-cancer
- Research C for DE and. FDA approves pembrolizumab for high-risk early-stage triple-negative breast cancer [Internet]. FDA. FDA; 2021 [cited 2022 Jan 20]. Available from: https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-pembrolizumab-high-risk-early-stage-triple-negative-breast-cancer
- Immunotherapy Side Effects [Internet]. Cancer Research Institute. [cited 2022 Jan 20]. Available from: https://www.cancerresearch.org/en-us/immunotherapy-side-effects
- Facts and figures about our research funding [Internet]. Cancer Research UK. 2017 [cited 2022 Jan 17]. Available from: https://www.cancerresearchuk.org/funding-for-researchers/facts-and-figures-about-our-research-funding-0
- What the NHS Long Term Plan means for breast cancer patients [Internet]. Breast Cancer Now. [cited 2022 April 13] Available from: https://breastcancernow.org/about-us/news-personal-stories/what-nhs-long-term-plan-means-breast-cancer-patients