This article is an abridged version of a longer, more technical, article written by A/Prof Warrier in association with Dr Grace Tapia, Dr David Goltsman and A/Prof Jane Beith and published on several international websites in 2016. It covers some of the many questions patients have asked us about research on breast cancer and related issues.
First the bad news: breast cancer is the most frequent cancer amongst women in the world with 1.7 million new cancer cases diagnosed in 2012 (25% of all cancers in women).
And breast cancer is the most common cause of cancer death among women and the second most common cancer death in developed counties after lung cancer.
But now to some good news: early detection and improving treatments have been associated with a reduction in breast cancer mortality rate.
It seems that breast cancer comes in many varieties and so does effective treatment.
Recent studies have shown that breast cancer consists of varying groups with distinct molecular features, risk factors, clinical presentation and response to therapies. The advent of new screening methods, advances in surgery, radiotherapy and chemotherapy, has allowed a more individualised treatment for breast cancer patients.
There are still many issues where clear cut answers are difficult to obtain and one size does not fit all. Some colleagues and I recently wrote a paper on these topics this is a brief summary; please contact my office if you would like the full paper.
Early breast cancer can be more effectively treated than advanced stages, when clinical signs and symptoms are present. Breast cancer screening allows detection of breast cancer in an asymptomatic phase and at an early stage. Different types of imaging and image-guided needle biopsies are used for breast screening.
Mammography represents the mainstay of breast cancer screening and this screening is associated with a reduction in breast cancer mortality, but it is not a uniform finding.
Screening recommendations vary by country and institution, some recommend mammographies starting at 40, others at 50 and the regularity recommendations also vary.
Even though mammography screening has increased the detection of ductal carcinoma in situ (DCIS) and early invasive cancers, the rates of advanced cancer have not changed dramatically in the last three decades.
While early detection is clearly a very good development, there is a continuing debate on overdiagnosis.
Although there is no single definition for overdiagnosis, it can be understood as the diagnosis of a condition in an asymptomatic person that does not produce a net benefit for that patient.
Overdiagnosis is not misdiagnosis, but rather the concept of a cancer being diagnosed during a patient’s lifetime that would not impact their life if not detected.
The existence of overdiagnosis due to mammographic screening is now widely accepted, however the estimated rates of its occurrence are conflicting. A number of breast working groups have looked at and many are continuing to investigate this topic.
Providing information about overdiagnosis and overtreatment to women who participate in breast screening programs will help them to make an informed decision about the time and frequency of their breast screening.
Bilateral prophylactic mastectomy (BPM) is an option in high-risk women who desire to reduce their risk of developing breast cancer. Likewise, women who have unilateral breast cancer may consider contralateral prophylactic mastectomy (CPM) to prevent a second breast cancer. However, as a preventive measure, prophylactic mastectomy remains controversial.
For women who have been diagnosed with a primary breast cancer, several studies have demonstrated that CPM is effective in reducing the risk of contralateral breast cancer.
Although prophylactic mastectomy (PM) can reduce the risk of breast cancer, it does not completely eliminate the risk as not all breast tissue can be removed. One potential benefit from risk reducing surgery is the potential of preventing sequelae (a condition which is the consequence of a previous disease or injury) of a cancer diagnosis for the patient. This includes the potential of having to have chemotherapy if a high-risk breast cancer is diagnosed in the future. Although not eliminated, this risk is reduced in high risk patients. It is essential that women who wish to undertake this procedure consider both the benefits and limitations of it, and weigh the risks and benefits of other alternatives such as chemoprevention, close surveillance or oophorectomy.
When considering a mastectomy, there have been a number of significant breakthroughs in operative technique. These can be subdivided into approaches to the skin and replacement of the gland.
Skin sparing and nipple sparing mastectomy: Maintaining the skin envelop and potentially the nipple areolar complex has allowed revolutionary outcomes in overall cosmetic results for patients undergoing these procedures. It is important to consider the technical challenges with these skin-preserving procedures based on the size of the breast, ptosis and co-morbidities (diabetes, smoking, BMI).
Glandular replacement: After removing all visible breast tissue, replacement of the gland is either by using an implant or autologous techniques. Implant techniques are either one or two stage techniques (expander first and then later a definitive implant is placed). The use of acellular dermal matrix materials (cadaveric and animal derived) has enabled the placement of immediate subpectoral implants with inferior border coverage. The increasing use of lipomodelling techniques has also allowed for revision of any minor deformities associated with these procedures.
Autologous tissue reconstruction is taken from the back (lattisimus dorsi flap) or the abdomen (Deep Inferior Epigatric Perforator flap).
The choice between prosthetic or autologous techniques reflects patient factors (such as the size of glandular replacement required and the amount of autologous tissue available) and patient choice, weighing up morbidity and durability of the different procedures. Ultimately, the decision about the choice of reconstruction should involve an informed discussion of the available options together with a discussion of the pros and cons of each.
The understanding of the complex nature and biology of breast cancer is allowing multidisciplinary teams to make better decisions regarding treatment. The detection of breast cancer in an early stage has improved survival outcomes. However, evidence about overdiagnosis and overtreatment are challenging breast cancer screening programs. The recognition of early breast cancer, detected by screening, which will not progress to an advance disease, is key to patients and their practitioners making informed decisions as to whether they would benefit from surveillance instead of surgery.