Breast Cancer

How Common is Breast Cancer?

Breast cancer is the leading cause of cancer death in women today in Singapore. Almost 1 in 16 women in Singapore will be diagnosed with breast cancer in their lifetime. Chinese women have a higher chance of developing breast cancer compared to Malay and Indian women. The highest rate of breast cancer occurs in women between the ages of 40 and 69 years. Fortunately, with earlier detection and improved treatment, more women are surviving the disease.

Singapore Cancer Registry Interim Annual Report, Trends in Cancer Incidence in Singapore, 2010 – 2014, National Registry of Diseases Office (released 26 May 2015)

What Causes Breast Cancer?

The causes of breast cancer are unknown, but there are many known risk factors such as a family history of breast cancer. Any woman can be at risk, especially for those who are 40 and above. Effective treatment is available for breast cancer if it is detected early, making regular screening a very important factor in increasing the success rates of treatment and recovery.

Symptoms of Breast Cancer may Include the Following: 

• Painless lump in the breast
• Persistent itch and rash around the nipple
• Bleeding or unusual discharge from the nipple
• Skin over the breast is swollen and thickened
• Skin over the breast is dimpled or puckered
• Nipple becomes pulled in or retracted

 

Guidelines on Breast Screening for Normal Risk Women without Symptoms:

39 years and below	Monthly breast self-examination
40 – 49 Years	Monthly breast self-examination Consider mammography screening once a year – discuss this with your doctor
50 – 69 years	Monthly breast self-examination Mammography screening once every 2 years

Patients with family history and other risk factors may need a different screening schedule – do consult your doctor.

How is Breast Cancer Diagnosed?

• Clinical examination – especially if there is a lump or nipple discharge, or an unusual breast change is detected.
• Mammogram – a special x-ray imaging tool that can detect abnormal masses in the breast like calcium deposits, cysts and tumours.
• Ultrasound scan – to examine abnormalities found in the mammogram. It can tell the difference between a solid mass, which may be a cancer, or a fluid-filled cyst which is usually not cancer.
• Magnetic resonance imaging (MRI) – an MRI scan can better examine areas of concern in the breast. This is useful for younger women because they tend to have higher breast tissue density, which could reduce the effectiveness of standard imaging tests (eg. mammogram and ultrasound) in detecting breast cancer.

What is a Biopsy?

A biopsy has to be done to confirm the presence of breast cancer. This involves the removal of the abnormal tissue to be examined closely under a microscope.

Common biopsy techniques:

• Fine needle aspiration (FNA)
• Core needle or tru-cut biopsy
• Excision biopsy

How is Breast Cancer Assessed?

Stages / Extent of Spread

Stage	Extent of Spread	Average 5-year Survival Rate (%)*
0	Non-invasive cancer	99
I	Small invasive cancer (less than 2cm without spreading to the axillary lymph nodes)	90
II	Invasive cancer (between 2 – 5cm or/with lymph nodes invasion)	70
III	Large invasive cancer (more than 5cm with skin invasion or spread to multiple lymph nodes)	40
IV	Widespread or metastatic cancer	20

*Individual patients may have a different experience depending on the specific characteristics of their breast cancer, and will influence which therapies can be used to target their cancer.

These characteristics of breast cancer can affect the chances of relapse and the patient’s survival rate.

Tumour Grade / Histologic Grade

This refers to how much the tumour cells look like normal cells when examined under the microscope, rated from grade 1 – 3. Grade 3 tumours contain very abnormal and quick growing cancer cells. The higher the histologic grade, the greater the chance of the breast cancer returning.

Lymph Nodes

The number of invaded (positive) lymph nodes, that are in the armpit on the side of the affected breast, is an important indicator of the chances of a successful recovery rate. A higher number of positive nodes will often result in a less positive outcome and requiring more aggressive treatments.

Tumour Size

In general, the larger the size of the tumour, the greater the chance of the breast cancer returning.

Oestrogen/Progesterone Receptors

Close to 2 out of 3 breast cancers cases involve significant levels of oestrogen and/or progesterone receptors. They are also known as oestrogen receptor positive (ER+) tumours. These tumours tend to grow less aggressively and may respond well to treatment with hormones.

HER2

HER2 is a protein that helps the growth of cancer cells and can found on the surface of certain cancer cells. A HER2-positive tumour is a type of tumour with an excess of the HER2 protein on its cells. These tumours tend to grow more quickly than other types of breast cancer tumours, and 20-25% of all breast cancer cases have these HER2-positive tumours.

Knowing if a cancer is HER2-positive can affect the choice of treatment because women with such tumours can benefit from HER2-targeted therapies. These include therapies that use drugs like trastuzumab (Herceptin®), pertuzumab (Perjeta®) or TDM-1 (Kadcyla®).

Surgery

Surgery can be a direct way to remove cancer from the body. Forms of surgery include:

1)    Breast-conserving surgery

• Lumpectomy or wide local excision – Removal of the cancer and a small amount of the surrounding tissue
• Quadrantectomy – Removal of the quarter of the breast where the cancer is found

 

2)    Mastectomy – Removal of the whole breast

During breast surgery, some of the lymph nodes under the armpit may also be removed for examination.

Radiotherapy

Radiotherapy uses high-energy rays to target and kill cancer cells. It can be used with other treatment procedures to kill any remaining cancer cells in or around the breast, thus lowering the chances of the cancer returning in the breast.

Radiotherapy can be vital after a breast-conserving surgery like lumpectomy, since much of the breast tissue is left intact.

Most women who have a mastectomy do not need radiotherapy. However, it can be used to treat the chest wall and the lymph nodes in the armpit if the risk of the cancer returning is high.

Systemic Therapy

Systemic therapy involves the use of drugs to treat the cancer cells wherever they are in the body.

• Chemotherapy
• Hormonal therapy
• Targeted therapy, eg. trastuzumab (Herceptin®) or pertuzumab (Perjeta®)

Rehabilitation

Physical rehabilitation includes:

• Shoulder exercises after the surgery
• Arm care, to avoid the beginning of lymphoedema (swelling of the arm(s) due to fluid retention)
• Balanced nutrition and lifestyle changes to improve recovery

Mental rehabilitation involves:

• Close support from your spouse, family and friends, as well as support groups
• Reassurance through a better understanding of the chances of survival
• Regular reviews with the doctor