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 25% of all cancers diagnosed in women are breast cancers. Between 2011 and 2015, about 1,927 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 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:
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.
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:
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.
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.
Large Core Needle Breast Biopsy (Mammotome®)
Mammotome® Breast 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.
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.
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
Sentinel Lymph Node Biopsy (SLNB)
X-ray Guided or Ultrasound Guided Hookwire Localisation for Surgery
Mammoplasty (Breast lift / Breast reduction)
Partial breast reconstruction (volume replacement) with a perforator flap
Mastectomy with Breast Reconstruction
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.
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.
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 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
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.
1. Can an injury to the breast cause cancer?
An injury to the breast cannot cause cancer. When the body tries to heal the bruise, it can develop scar tissue. This scar tissue can be mistaken as cancer on mammogram. However, symptoms of injury should subside within a month. If you are worried, seek confirmation from your doctor.
2. Are most breast lumps caused by cancer?
No. Only one lump out of every 10 will be cancerous. This means that 90% of all breast lumps are not cancer. However, the chance of a lump being cancerous increases as you get older. Some women do not have a definite lump, but can feel areas of general ‘lumpiness’ in their breasts. Often, your doctor will be able to reassure you that this is normal but it is important that you ask your doctor to check thoroughly for any change.
3. Can a benign (non-cancerous) lump turn into cancer?
The chances of cancer developing in a benign lump may be no different than in any other part of the breast. However, it is very important for you to make sure that the lump is non-cancerous in the first place.
4. If I have a benign breast problem, am I more likely to get breast cancer?
Occasionally, the risk is slightly higher in some women with particular benign breast problems. However, you will need to talk this over with your doctor.
5. Do benign problems come back?
Generally, no. However, a small number of women will develop new benign lumps in the future.
6. I felt a lump in my breast, but it didn’t show up in the mammogram. Does that mean I don’t have cancer?
A lot of women who find lumps in their breasts get frightened and they go for a mammogram. When nothing shows up, they’re very happy because they assume it’s not cancer. No test is perfect. Ask your doctor to conduct more tests and find out the cause of the lumps. Even though many breast lumps are not cancerous, you should still bring it to your doctor’s attention.
7. What if the lump turns out to be cancer?
If breast cancer is detected early, it has a better chance of being cured. You will need to discuss the diagnosis and the best treatment options with your treating doctor.
8. What should I do if my doctor says my breast problem is nothing to worry about but I still feel concerned?
If your doctor has suggested your problem is hormonal, you may wish to wait until after your next period to see if the problem is still there. If it persists or if you are still concerned, you may wish to go back to your doctor or seek a second opinion.
9. What if there is a history of breast cancer in my family?
Women who have a strong family history of breast cancer, such as a mother and/or sister who developed breast cancer before menopause, may be at increased risk of getting breast cancer. If you are concerned about a family history of breast cancer, talk with your doctor. You may also wish to consult a breast specialist.
10. Will I still have my menstrual periods after breast cancer treatment?
Treatment with chemotherapy and hormonal therapy may cause changes in your menstrual cycle, resulting in irregular menstruation or early menopause. If you are already reaching menopause, your menstrual periods may not return.
11. Can I become pregnant when I have breast cancer?
The belief is that changing levels of female hormones during pregnancy could encourage the recurrence of breast cancer. However, there is no data to show that this is so. Some doctors will advise you to wait one or two years after completion of treatment before attempting to conceive. Nevertheless, do discuss with your doctor before planning to conceive.
12. When is a mastectomy recommended?
Some women do better cosmetically with a mastectomy than with the removal of just the lump, since breast reconstruction is now available using tissue expanders or skin flaps. Your surgeon will be able to advise if you are suitable for breast reconstruction.
The Singapore Cancer Society has a Reach to Recovery Programme that provides physical, cosmetic, post-operative and psychological support. The volunteer is usually a female who has undergone a mastectomy.
Early Detection & Prevention
1. If I go for mammogram screening regularly, will I be exposed to dangerous levels of radiation?
Radiation exposure from modern mammogram equipment is believed to be safe.
2. I have a lump in my breast. I am frightened to see the doctor in case it is cancer.
Although your worry is understandable, you should see your family doctor as soon as possible. The great majority of breast lumps are not cancerous.
3. My mother / aunt died of breast cancer. Am I likely to get breast cancer too?
A small proportion of breast cancer is linked to factors that can be inherited from one generation to the next. Depending upon the number of close relatives affected, you may have a greater chance than a woman who does not have a family history of breast cancer. Most family doctors or hospitals will provide information on breast self-examination and mammogram screenings.
1. I have been diagnosed to have breast cancer. Will I get better?
Many women who have had breast cancer live a normal lifespan. Feel free to discuss your own prognosis with your doctor.
2. Will I need to undergo mastectomy?
This depends on the size, position and type of your breast cancer as well as the size of your breast.
3. Does radiotherapy or chemotherapy cause disfigurement and long-term damage?
It is uncommon for women to experience lasting damage from modern radiotherapy techniques. Most chemotherapy side-effects are short-term. Nausea and vomiting are controlled in most patients. Hair loss is still common, and you may require a temporary wig. Your periods may disappear during chemotherapy but may return when you complete chemotherapy. However, for women in their late 30s and 40s, menopause may occur early, perhaps increasing the risk of osteoporosis and heart disease. If a fever occurs while you are on chemotherapy, see your doctor immediately in case antibiotics are needed.
Hormone therapy for Breast Cancer
1. Why do I need hormone therapy?
Normal female hormones like oestrogen may promote growth of normal healthy breast tissue, but may also accelerate the growth and recurrence of certain breast cancers. Drugs that slow breast cancer growth by interfering with normal female hormone action are generically called hormone therapy. Some breast cancers need the hormone, oestrogen, to grow. Hormone therapy can prevent your body’s natural hormones from activating growth or spread of cancer cells.
2. What drug will I be given? What does it do?
The most common drug used for hormone therapy for breast cancer is the oral tablet, tamoxifen, which stops the action of oestrogen.
3. Will I have any side effects? What can I do about them?
You may experience any of the following common side effects:
Hot flushes/sweats. Wear a thin layer of clothing to keep cool when hot flushes occur.Vaginal irritation. Some women experience vaginal dryness or discharge. Notify your doctor who can recommend a non-oestrogen cream or lubricant.Irregular menstrual periodsSome pre-menopausal women experience irregular periods. Some women may find that once they stop taking tamoxifen, their menstrual cycle becomes regular again.
Other less common side-effects are depression, mood swings and a slightly increased chance of developing cancer of the uterus and deep vein thrombosis. Regular gynaecological checkups are recommended.
4. How long will I be on hormonal treatment?
When used to treat early breast cancer, tamoxifen is most often prescribed for 5 years. Patients with advanced disease may take it for varying lengths of time depending on their response to treatment.
5. Why do some women need hormonal treatment while others do not?
Many breast cancers have ‘receptors’ for oestrogen and progesterone. Receptors are proteins on the surface of the cancer cells to which specific hormones (e.g. oestrogen or progesterone) attach themselves. If the cancer has oestrogen or progesterone receptors, it is likely that hormonal treatment would benefit this group of women.
1. What choice of prosthesis (breast forms) do I have?
There is a wide range available. The type of breast form you require will depend on your needs. It should closely simulate the weight and shape of a natural breast and your other breast. If you need advice, speak with your Breast Care Nurse.
2. Can the prosthesis be washed? How do I take care of it?
Yes, the prosthesis can be washed. Instructions on the care of the prosthesis can be found in the box when you purchase one. You should also place the prosthesis in the box when you are not using it.
1. What is a Breast Reconstruction?
Breast reconstruction is an operation to create a new breast to replace the breast which has been removed. Breast reconstruction does not affect breast cancer survival or treatment. The procedure can be performed at the same time as the mastectomy or at a later date. The breast can be reconstructed using an implant such as silicone, normal saline or tissue from your own body. This procedure requires further discussion with your surgeon.
2. When can breast reconstruction be done?
There are differing opinions on this. It can be done at the time of mastectomy, some months afterwards or even years later. The timing may depend on the type of breast cancer you have, whether you need further treatment (e.g. chemotherapy), how you feel about the loss of your breast or breasts, your general health, and other concerns such as costs. Talk over these issues with your breast surgeon and plastic surgeon. You may wish to ask for a second opinion if you would like one.
3. Can I exercise after breast reconstruction?
It will be helpful to stay active and to exercise regularly if you can. Light exercise, such as walking after surgery, can assist in the recovery process. The amount and type of exercise will depend on what you are used to and how well you feel. It is best to discuss your concerns with your doctor.
4. Do I need to go for regular breast screening after a reconstruction?
It is important to have regular scheduled mammograms on the opposite breast. Breast self examination should continue. Check both the remaining and the reconstructed breast at the same time each month. You will learn what is normal for you since the breast reconstruction. The reconstructed breast will feel different and the other breast may have changed too.
1. After being diagnosed with breast cancer, can I still breastfeed my baby?
You can still breastfeed your baby from the unaffected breast. It is not advisable to breastfeed your baby on the breast that is affected by cancer, as it will not be able to produce adequate milk.
2. Can I breastfeed after lumpectomy and radiation therapy?
Yes, you can. Lumpectomy is not so extensive that it will affect your breastfeeding capacity, but radiation therapy will. The breast treated with radiation may go through the same changes as the normal one during pregnancy, but it will produce little or no milk. You can, however, breastfeed your baby with the other breast.
3. Can I breastfeed after mastectomy?
Yes, you can still breastfeed your baby with the other breast. Frequent nursing will be necessary at first so as to build up a good supply of milk.
4. Will I be able to breastfeed after a biopsy?
Yes. A biopsy will not interfere with your ability to breastfeed. Even if you need a biopsy while you are breastfeeding, you can still continue to breast-feed. However, you will need to discuss this with your doctor.
1. Why do I need to exercise?
You are encouraged to exercise your affected arm soon after your operation to prevent stiffness of the shoulder joint.
2. When can I start doing arm exercises?
It is normal to feel tired for a few days after an operation. You can start the exercises as soon as you feel strong enough. This can be as early as the first day after your operation. The sooner you start, the faster you regain your shoulder movements.
For more information on Breast Cancer FAQs, please click here.
The information provided on this page does not replace information from your healthcare professional. Please consult your healthcare professional for more information.
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