Breast cancer is the abnormal growth of cells in the breast. These cells grow and develop into a cancerous growth that can have the potential to spread to other parts of the body.
Is breast cancer hereditary?
In 5-10% of cases, breast cancer is hereditary. The cancer is caused by specific gene mutations (changes) in the BRCA1 (BReast CAncer gene one) and BRCA2 (BReast CAncer gene two) genes.2 There are several other genes other than BRCA1 and BRCA2 that also help make up this percentage.
These genes can develop abnormally which may then be passed down through family generations, increasing the chance of breast (and ovarian) cancers.2
Stages of breast cancer
Breast cancer is typically classified into stages from 0 – IV based on:
- tumour size (T)
- if the cancer has involved any lymph nodes (N)
- whether the cancer has metastasised (spread) to other parts of the body (M).3
Stage 0 is the earliest stage of breast cancer and Stage IV is the most serious, meaning the cancer has spread to other parts of the body.4
Signs and symptoms of breast cancer
Normal breast tissue often feels lumpy, so it can be difficult to know the difference between what is normal and what could be a cancerous lump.
Some common symptoms of breast cancer to keep an eye out for include: 5
Any new lumps
Discharge of fluid
Dimpling or a ‘pulling’
Breast pain or swelling
Dry, flaky red skin
Breast cancer diagnosis involves a number of tests. You may undergo a mammogram, which takes an x-ray of your breast to check for signs of cancer; an ultrasound of the breast to identify tumorous masses and differentiate between benign and malignant tumours; an MRI, which determines the size and extent of the cancer; a blood test, to examine the breast cancer index; or a breast biopsy, which involves removing tissue from the tumour to examine.
Further tests may also be required, often to see if the cancer has spread beyond the breast, including a PET scan.
There is no single cause of breast cancer, however there are are a number of risk factors that can increase your chance of developing breast cancer including genetic, lifestyle and environmental factors.
These can include:
- Gender – being female increases your risk
- Having a family history of, or close relative who has had, breast cancer
- Aging – women who are 50-years-old are 10 times more at risk to develop breast cancer than women who are 30-years-old 11
- Drinking alcohol 11
- Being overweight
- Periods that start very young or stop later than usual
- Long-term use of oestrogen (including contraceptive pills)
- A history of fibroadenoma and/or ductal hyperplasia, especially atypical ductal hyperplasia (ADH)
There is convincing evidence that combined (oestrogen-progesterone) replacement therapy increases the risk of breast cancer.11
Risk increases the longer that HRT is used, and is higher in women who start replacement therapy close to menopause.11
There are several lifestyle factors you can control to help reduce your risk of developing breast cancer, including:
- Getting regular exercise – At least 30 minutes of moderate-intensity exercise each day12
- Eating a healthy, balanced diet – Eat a fibre-rich diet from grain and legume sources, as well as enjoy a variety of fruit (2 serves) and vegetables (5 serves) per day, limit your intake of salt, saturated fats, and avoid all processed meat13
- Reducing alcohol intake – If you choose to drink, limit your alcohol intake to no more than two standard drinks a day. 11
- Maintaining a healthy weight – Maintain a healthy weight within the normal BMI (Body Mass Index)* range of 18.5 – 24.9kg/m2.14
*To calculate your BMI = (weight (kg))/(height(m))2
The Breast Cancer Foundation can provide you with more information about the different stages of breast cancer.
Breast cancer in men is rare and only makes up approximately 1% of all breast cancer cases.
Like women, there are a number of factors that can increase male breast cancer risk. These include: 20
- Age – the average age of breast cancer diagnosis is 69 years
- Family history of breast cancer, or a known BRCA gene mutation
- Hormonal imbalances – such as increased levels of oestrogens
- Previous radiotherapy treatment
For more information, click here.
- Breast cancer. (2019). Health Hub. Retrieved on 29 May 2019
- Breast Cancer – What it is. (n.d). Sing Health. Retrieved on 29 May 2019
- Stages, types and treatment of breast cancer. (n.d). National Breast Cancer Foundation. Retrieved on 18 December 2018
- Breast Cancer Stages. (2017). American Cancer Society. Retrieved on 19 December 2018
- What are the symptoms of breast cancer. (2018). Centre for Disease Control and Prevention (CDC). Retrieved on 18 December 2018
- Breast Self Examination. (n.d). Breast Cancer Foundation. Retrieved on 30 May 2019
- Surgery for breast cancer. (2016). American Cancer Society. Retrieved on 18 December 2018
- Radiation for breast cancer. (2017). American Cancer Society. Retrieved on 18 December 2018
- Chemotherapy for breast cancer. (2017). American Cancer Society. Retrieved on 18th December 2018
- Hormone therapy for breast cancer. (2017). American Cancer Society. Retrieved on 18 December 2018
- Risk factors for breast cancer: A review of the Evidence. (2018). Cancer Australia. Retrieved on 18 December 2018
- Physical Activity and sedentary behaviour. (n.d). Cancer Australia. Australian Government. Retrieved on 18 December 2018
- (n.d) Cancer Australia. Australian Government. Retrieved on 18 December 2018
- Overweight and obesity. (n.d). Cancer Australia. Australian Government. Retrieved on 18 December 2018
- Stage 0 – pre-breast cancer. (n.d) National Breast Cancer Foundation. Retrieved on 13 January 2019
- Stage 1 or 2 – Early breast cancer. (n.d). National Breast Cancer Foundation. Retrieved on 13 January 2019
- Stage 2 or 3 – Locally advanced breast cancer. (n.d). National Breast Cancer Foundation. Retrieved on 13 January 2019
- Stage 4 – Metastatic breast cancer. (n.d). National Breast Cancer Foundation. Retrieved on 13 January 2019
- Targeted Therapies. (n.d). Icon Cancer Centre. Retrieved on 13 January 2019
- Men get breast cancer too. (2016). Breast Cancer Network Australia (BCNA). Retrieved on 14 January 2019