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Breast Cancer

Breast cancer: Symptoms, causes and risk factors

Breast Cancer - What it is

Breast cancer: What it is

Breast cancer arises from a malignant tumour. It occurs when breast cells become abnormal and divide without control or order. Normal cells divide and produce in an orderly manner. Sometimes this orderly process is disrupted and cells grow and divide out of control, producing extra tissue to form a mass or lump called a tumour. A tumour can be benign (non-cancerous) or malignant (cancerous). The breasts are made up mainly of fat cells and gland cells. Milk-producing glands in the breast are made up of individual cells which normally reproduce under the control of hormones. Sometimes this process of reproduction goes out of control and an abnormal glandular structure develops. This is the beginning of cancer. The majority of breast cancers starts in the milk ducts. A small number start in the milk sacs or lobules.

How Common is Breast Cancer?

More than 29% of all cancers diagnosed in women are breast cancers. Between 2014 and 2018, about 2,246 women were diagnosed to have breast cancer in Singapore each year.

Nine out of 10 women who go to their doctors with breast lumps have a benign disorder, not cancer. Normal changes associated with the menstrual cycle can make breasts feel lumpy.

Age of onset

The risk of breast cancer increases with age. Most women who are diagnosed to have breast cancer are older than 40 years old, but younger women may also be affected.

Breast Cancer - Symptoms

Breast cancer is painless especially during the early stage. In fact, there may be no symptoms at all when breast cancer first develops, so watch out for changes in the breast. These are often the first signs that cancer is present:

  • A persistent lump or thickening in the breast or in the axilla.
  • A change in the size or shape of the breast.
  • A change in the colour or appearance of the skin of the breast such as redness, puckering or dimpling.
  • Bloody discharge from the nipple.
  • A change in the nipple or areola, such as scaliness, persistent rash or nipple retraction (nipple pulled into the breast).

If you notice any of these changes, you should see a doctor immediately. Most often, they are not due to cancer, but only a doctor can tell for sure.

Breast Cancer - How to prevent?

Breast Cancer - Causes and Risk Factors

Being a woman puts you at risk of getting breast cancer. This risk increases as you grow older. Several factors further increase your risk. A woman is at a higher than average risk for breast cancer if one or more of the following applies to her:

  • Family history of breast cancer, especially in a first-degree relative (mother, sister or daughter), or two or more close relatives such as cousins
  • Genetic alterations in certain genes such as BRCA1 and BRCA2
  • Benign conditions such as atypical ductal hyperplasia, atypical lobular hyperplasia or lobular carcinoma in-situ diagnosed on breast biopsy
  • Early menarche (onset of menstruation) before the age of 12
  • Late menopause (after the age of 55)
  • Never had children
  • Late childbearing (after the age of 30)
  • Personal history of breast cancer
  • Obesity
  • Excessive weight gain in post-menopausal women
  • Lack of exercise
  • Excessive alcohol consumption over a long period of time
  • Use of combined hormonal replacement therapy (HRT) for a long period of time

However, most women who have breast cancer have none of the above risk factors. Likewise, not possessing any of these risk factors does not mean that you will not get breast cancer. There are ongoing researches to learn more about these factors, as well as, ways to prevent breast cancer.

Breast Cancer - Diagnosis

If you notice any lumps or unusual changes in your breasts, you should see a doctor. Try to pinpoint the area accurately as this will assist your doctor with the examination. Your doctor may advise you to undergo some tests so that a definite diagnosis can be made. These tests may include one or more of the following:


If you have breast symptoms, you may need to have a mammogram to help with the diagnosis. The mammogram checks for the presence and position of the abnormality. To do this, more detailed x-rays may be needed as compared to those taken for a mammogram screening. Sometimes a lump that can be felt is not seen on a mammogram. Other tests are often necessary to determine whether the lump is cancerous or not. If you have recently had a mammogram, remember to bring with you the x-rays (and report if available) when you see the specialist.


Breast ultrasound is the use of high frequency sound waves to produce an image of breast tissue. Ultrasound does not use radiation. The doctor or radiographer does the scanning. This test can differentiate a fluid-filled cyst from a solid lump.

Magnetic Resonance lmaging (MRI)

A diagnostic test that uses magnetic fields to capture multiple images of the breast tissues. These images are combined to create a picture of the inside of the breast. This test does not use radiation and is completely painless.

Fine Needle Aspiration (FNA)

For this test, your doctor uses a syringe with a very fine needle to withdraw fluid or cells from a breast lump. This can be uncomfortable but is usually not painful. If the lump is just a cyst, withdrawing fluid in this manner will usually make the cyst disappear. However, if the lump is solid, your doctor may use this procedure to withdraw some cells from it. The cells will then be sent to a laboratory for examination.

Core Needle Biopsy

This method obtains a few slivers of tissue from an area of abnormality with a wide bore needle. Local anaesthetic is used to numb the breast area first, followed by a small incision in the skin to allow easy insertion of the needle. If the abnormality cannot be felt easily, the procedure can be performed with ultrasound or x-ray guidance.

Vacuum Assisted Breast (VAB) Biopsy

Vacuum Assisted Breast (VAB) Biopsy uses a vacuum-assisted device to obtain tissue samples from non-palpable lesions. Small samples of tissue are removed from the breast using a large bore needle which is guided precisely to the suspicious lesion via x-ray or ultrasound.

A small titanium clip (microclip) may be placed at the biopsy site to act as a location marker for future treatment. An x-ray is taken during post-biopsy to ensure proper clip placement.

This procedure is minimally invasive as compared to an open surgical biopsy. It is performed as a day surgery procedure. It has the ability to sample tiny abnormalities called microcalcifications, making early diagnosis of breast cancer possible. It is done under local anaesthetic and takes about 30 to 45 minutes to complete. The procedure is usually not painful but you may experience some discomfort.

Excision Biopsy

An excision biopsy involves the surgical removal of a lump or sample of suspicious tissue for examination under a microscope to give a definite diagnosis. Sometimes, ultrasound or x-ray pictures are taken to insert a small thin wire to the abnormal spot in the breast. This wire is used to guide the surgeon to the right spot of abnormal lesion for removal. The technique is known as hook wire localisation biopsy.

Biopsies can be performed either under local or general anaesthetic, depending on the size and position of the lump. You can leave the hospital on the same day. If you are unsure of how the biopsy will be done, you may want to ask the surgeon to explain how the procedure is done before you undergo it.

Breast Cancer - Treatments

Treatment of breast cancer may include various methods, such as surgery with or without breast reconstruction, chemotherapy, radiation therapy, hormonal therapy and targeted therapy. Treatment options offered depend on a number of factors, such as the stage of cancer and likelihood of cure, your general health and your preference. Being diagnosed with breast cancer and having to decide on the treatment option is one of the most difficult decisions you will ever have to make. Have someone close to accompany you when visiting the doctor to discuss the result of your tests and treatment options.


A lumpectomy or mastectomy is one of the most common treatments for breast cancer. The type of surgical treatment depends on the stage of the cancer, size of the tumour, in relation to the breast size, whether breast preservation is desired and your feelings about the options.

Breast Conserving Surgery (BCS) Wide Excision/ Lumpectomy

  • Your surgeon will remove only the breast cancer and a rim of normal surrounding breast tissue.
  • Your breast will remain. A scar and some changes in shape and size are expected.
  • You can go home the next day.
  • You may require a second operation if cancer cells are noted at the edge of the removed portion. This occurs in 10-15% of patients.
  • You will need to have radiation therapy to the breast (Mon to Fri) for 4-6 weeks. This helps to destroy any remaining cancer cells.

Sentinel Lymph Node Biopsy (SLNB)

  • If you have early stage breast cancer, and the lymph nodes in your underarm do not appear to have cancer, SLNB will be carried out.
  • The first few lymph nodes (sentinel lymph nodes, SLN) in your underarm where the lymphatic vessels from the breast drain to, will be removed and examined during surgery under the microscope (frozen section).
  • This is done under General Anaesthesia GA (asleep) and it is to determine if cancer has spread to these SLN.
  • A blue dye or a radioactive substance is injected around the cancer site or at the nipple prior to surgery to locate the SLN.
    - The radioactive substance will be injected before the operation in the Department of Nuclear Medicine.
    - The blue dye will be injected during the operation.
  • If cancer is detected in the SLN, lymph nodes in the axilla are removed. If no cancer is detected in the SLN, no further surgery is needed.
  • The final histology will be reviewed about 1 week after surgery.
  • In 2 - 3% of cases, the final assessment of the SLN may be different from the initial frozen section result and a second operation may be required.
  • If the dye or radioactive substance is not able to identify the SLN, we will have to proceed to perform an axillary clearance.

Axillary Clearance

  • Involves the removal of all lymph nodes from the underarm.
  • This is needed because the lymph nodes are found to have cancer cells.
  • Side Effects:
    1. Shoulder stiffness.
    2. Swelling of the arm (lymphedema) 15-20%.
    3. Numbness of the inner part of your upper arm.

X-ray Guided or Ultrasound Guided Hookwire Localisation for Surgery

  • This procedure is performed under local anaesthesia, before you go for surgery.
  • Mammogram or ultrasound guidance is used to place a fine wire within the breast in close proximity to the lesion of interest.
  • This wire marks the lesion to be removed.
  • The wire and lesion of interest will be removed during the surgery.

Oncoplastic Breast Conserving Surgery

Mammoplasty (Breast lift / Breast reduction)

  • All the points for Breast Conserving Surgery mentioned earlier are applicable.
  • In addition, you will benefit from the re-shaping of the breast after cancer removal.
  • This is performed to reduce breast deformity and improve the final appearance of the breast after cancer removal.
  • If your cancer is large, the final breast volume may be smaller. Surgery to the opposite breast for better symmetry may be performed at the same time, or at a later date.
  • Speak to your surgeon for specific details of this surgery.

Partial breast reconstruction (volume replacement) with a perforator flap

  • All the points for Breast Conserving Surgery mentioned earlier are applicable.
  • You are suitable for partial breast reconstruction (volume replacement) with breast conserving surgery.
  • Fatty tissue next to your breast will be used to fill the space in the breast that results from cancer removal.
  • This maintains breast volume and contour, reducing breast deformity.
  • Speak to your surgeon for specific details on this surgery.

Simple Mastectomy

  • The entire breast, including the nipple-areola complex is removed. After surgery, a neat and flat chest wound is expected.
  • A soft tubing known as a drain is placed during surgery with the accompanying bottle to remove blood and fluid accumulated at the operated site.
  • The drain is removed when the drainage is less than 30ml/ 24h after 1-2 weeks. You will be taught how to care for the drain.
  • You can go home the next day.

Mastectomy with Breast Reconstruction

  • Immediate: You have chosen to have breast reconstruction at the time of mastectomy.
    - Skin sparing mastectomy: where most of the skin of your breast will be preserved.
    - Nipple sparing mastectomy: In suitable cases, the nipple may be preserved if tissue from the base of the nipple shows no cancer cells when tested at the time of surgery. However, if the final histology results show cancer cells behind the nipple, you will be recommended a simple surgery to remove it.
  • Delayed: Breast reconstruction may also be done at a later stage, separate from the initial breast surgery.

Types of Breast Reconstruction

Flap reconstruction

  • Skin, fat and sometimes muscle (a flap) from another part of your body may be used to make it into a breast shape.
  • The operation duration is about 6 - 8 hours.
  • Hospital stay is between 1 - 2 weeks.
  • Several drains are used and removed after 1 - 2 weeks.
  • Flaps may be from the:
    - Back (latissimus dorsi)
    - Abdomen
    - Trans-rectus Abdominis Muscle (Tram) Flap Reconstruction
    - DIEP (deep inferior epigastric perforator) flap, taking skin and fat only Buttock/Thigh

Flap reconstruction

Breast Implants

  • Silicone implants may be used to create a new breast.
  • The operation duration is about 4 - 5 hours.
  • Usually there are 2 - 3 drainage bottles inserted.
  • Hospital stay is 3 - 5 days.
  • 1-stage: The permanent implant is inserted at the time of mastectomy.
  • 2-stage: A temporary expander may be placed at time of mastectomy, and gradually expanded to stretch the skin and the expander is exchanged for a permanent implant at a later surgery.

Breast implants


This treatment method uses anti-cancer drugs to kill cancer cells. They stop cancer cells from growing and reproducing themselves. These drugs can be given orally (by mouth) or by injection where it enters the blood stream and travels throughout the body. It may be used alone, before (neoadjuvant) or after (adjuvant) surgery, or together with radiation therapy to increase the effectiveness of treatment, depending on the stage of cancer.

Chemotherapy is given in cycles. Each cycle consists of a treatment period followed by a resting (recovery) period. As cancer drugs also affect normal cells, the resting period is to allow the body to recover before the next treatment cycle starts. There are side effects associated with chemotherapy such as hair loss, nausea and vomiting, loss of appetite, mouth ulcers and risk for infection. However, these are temporary and steps can be taken to prevent or reduce them.

Radiation Therapy

High-energy rays are used to kill cancer cells or stop them from growing further. Although radiation therapy can affect both cancer cells as well as normal cells, the aim of radiation is to destroy more cancer cells and spare as many normal cells as possible. Radiation therapy is given to the affected breast after a lumpectomy. In some circumstances, it may be given to the chest wall after a mastectomy. It is given 5 days a week on weekdays, over a period of 5 or 6 weeks. Radiation therapy can cause some side effects which vary among individuals.

The most common side effect is redness and dryness of the skin. Skin texture also becomes darker and thicker. The breast may swell, and increase or decrease in sensitivity. Usually, these effects start to get better when your treatment is completed.

Intraoperative Radiation Therapy (IORT) involves the use of the Intrabeam® device to irradiate the tumour site during the surgery. The administration is done immediately after lumpectomy, also known as breast-conserving surgery. This procedure takes about 20 to 40 minutes. This radiotherapy regime is suitable for some early-stage patients. This treatment may be proposed to patients in the early stage of the disease who opt to keep their breasts.

Hormone Therapy

Some breast cancers grow with the influence of hormones. Patients with both oestrogen receptor (ER) and progesterone receptor (PR) positivity have the best chance of responding to hormonal therapy. Hormone therapy in breast cancer is aimed at affecting oestrogen, a hormone that is required for the cancer to grow. For some women with early breast cancer, anti-cancer hormone treatment may be used as an additional treatment to reduce the chances of breast cancer recurrence. Hormone therapy can cause some side effects. These are dependent on the type of drugs taken and can vary from one patient to another.

Tamoxifen is the most common drug used in this treatment. This drug blocks the action of oestrogen on the body but does not stop oestrogen from being produced. Tamoxifen may cause hot flashes, depression or mood swings, vaginal discharge or irritation, irregular menstrual periods and sometimes menopause. Any unusual bleeding should be reported to the doctor.

Serious side effects from Tamoxifen are rare but Tamoxifen can cause the formation of blood clots in the veins, especially in the legs. In a very small number of women, Tamoxifen can cause cancer in the lining of the uterus. You may be referred to a gynaecologist to evaluate any unusual bleeding.

Aromatase Inhibitors (AI)

For post-menopausal women, another group of drugs called aromatase inhibitors (AIs) is also used in breast cancer hormonal treatment. Aromatase inhibitors work by blocking an enzyme called aromatase that the body uses to produce oestrogen. The current AIs such as anastrozole, letrozole and exemastane, are well tolerated and are used in the treatment of early stage and advanced breast cancer. Side effects of AI include hot flashes, mood changes, nausea, vagina dryness, joint pain/stiffness, tiredness, lethargy and osteoporosis (including a higher risk of fractures compared to Tamoxifen).

You can discuss with your doctor, Breast Care Nurse or pharmacist on what to expect and how to care for yourself during treatment. If there are more concerns, you can also contact the Cancer Helpline at tel: 6225 5655.

Targeted Therapy

Targeted therapy is a form of cancer treatment that involves the use of antibodies or small molecules to bind to specific sites on cancer cells in order to prevent cell growth and division. The aim of the treatment is to reduce or eliminate existing cancer cells in the human body while minimizing side effects on normal cells.

An example of targeted therapy for breast cancer is Trastuzumab (Herceptin®). It is an antibody which targets the HER2 (Human Epidermal Growth Factor Receptor). This receptor is over expressed in about 25% of all breast cancers, the presence of which can be confirmed by laboratory tests performed on the biopsy specimen and which is required for the drug to be effective.

Herceptin® has been shown to prolong survival in patients with HER2 positive advanced breast cancer (Stage 4) and reduce the risk of relapse in patients with early stage HER2 positive breast cancer, when used in combination with chemotherapy.

An increasing number of targeted therapies are becoming available for the treatment of breast cancer, including:

  • Pertuzumab (Perjeta® targets HER2)
  • Lapatinib (Tykerb®targets HER2 and EGFR)
  • Palbociclib (Ibrance® targets cell cycle pathway in hormone positive breast cancers)
  • Ribociclib (Kisqali® targets cell cycle pathway in hormone positive breast cancers in hormone positive breast cancers)
  • Everolimus (Afinitor® targets mTOR pathway in hormone positive breast cancers)

Patients who receive targeted therapies may still experience side effects but these are generally milder and less common compared to chemotherapy.

Breast Cancer - Preparing for surgery

Breast Cancer - Post-surgery care

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