October marks breast cancer awareness month, an annual international health campaign organized by major charities to increase awareness of breast cancer and raise funds for research into the cause, prevention, diagnosis, treatment, and cure. Herein, I would like to discuss frequently asked questions about breast cancer.

What is breast cancer? Breast cancer develops from breast tissue, commonly from cells lining the milk ducts or the lobules that supply these ducts with milk, known as ductal carcinomas and lobular carcinomas, respectively. There are more than 18 sub-types, including ductal carcinoma in situ (DCIS), which develops from pre-invasive lesions. 

How is breast cancer diagnosed? A breast cancer diagnosis is confirmed by biopsy of the concerning tissue. Further tests establish if cancer has spread beyond the breast and which treatments are most likely to be effective. 

Who gets breast cancer? In Ontario, breast cancer is the most frequently diagnosed cancer in women, and 1 in 8 women will be diagnosed with breast cancer in her lifetime. The five-year survival rate is between 80 and 90%. Although the causes of breast cancer are unknown, many factors may increase the chances of getting breast cancer, including age, never giving birth, alcohol use, obesity, sedentary lifestyle, family history, and mutation of BRCA1 or BRCA2 genes.

Should I get screened for breast cancer? Although the balance of benefits to the harm of breast cancer screening is controversial, for women between the ages of 50-70, the Ontario breast screening program recommends a mammogram every two years. A doctor’s referral is not required, and it is covered by OHIP. Studies show that regular mammograms lower the risk of dying from breast cancer.

What is breast cancer staging? To understand and treat a breast cancer diagnosis, the stage of cancer is an important consideration. The information obtained from staging establishes the size and location of the primary tumour, the spread of cancer to nearby lymph nodes or other parts of the body, tumour grade, and whether certain biomarkers are present. Establishing the breast cancer stage combines information from the TNM system (tumour tissue, T; lymph nodes, N; metastasis, M), the grading system (low, intermediate, high) and detection of genetic markers.

What are the stages of breast cancer?  The stages of breast cancer range from 0 to 4 and may include letter designations. In stage 0 and stage 1, the cancer cells are contained to the breast tissue and are effectively treated. In stage 2, the breast cancer may be contained, or growth has extended to the sentinel lymph nodes located in the armpit. Chemotherapy is usually done, followed by surgery and radiation. In stage 3, the cancer has invaded nearby lymph nodes but has not spread to distant organs. Stage 3 is advanced, but there are several effective treatment options. In stage 4, the cancer has spread to other parts of the body, such as the brain, bones, lungs, and liver. Stage 4 is not curable, and treatments may focus on quality of life. 

Is stage 0 breast cancer considered cancer? In Stage 0 breast cancer, the atypical cells have not spread into the surrounding tissue. DCIS, for example, is a non-invasive cancer referred to as stage 0 and the most common type of breast cancer. DCIS does require treatment, typically surgery or radiation, or a combination of the two; if left untreated or undetected it can spread and progress to further stages.

What are the biomarkers associated with breast cancer? Biomarker testing identifies expression of the genetic markers estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor type 2 receptor (HER2/neu or HER2). Breast cancer is called positive for a given biomarker if they have receptor expression or negative if they do not. Some tumours are described as triple-negative or triple positive, referring to the presence or absence of all three markers. Knowing the biomarker status allows the oncologist to choose the best treatments. 

What can I do to help? Donate, fundraise, and support efforts raised by the Canadian Cancer Society and other organizations to fund ground-breaking research. 

We have all been impacted by breast cancer, hearing of friends or family members dealing with a personal or a loved one’s diagnosis, underscoring the importance of awareness to ameliorate the lives of those affected. Through the continued support of breast cancer awareness, we can strive to create a future without breast cancer.

Submitted by: Dr. Oliver Kent, Cancer researcher and Senior Scientist at adMare BioInnovations.  

Do you have an idea or question you would like to read about in the Cancer Chat? Email (kent.uhn@gmail.com) or text (438-874-6546) and let me know!