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Breast cancer

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Potential side effects of surgery for breast cancer

Side effects can occur with any type of treatment for breast cancer, but not everyone has them or experiences them in the same way. Side effects of surgery will depend mainly on the:

  • type of surgery
  • woman’s overall health
  • effect of other cancer treatments, such as radiation therapy

Side effects can happen any time during surgery. Some may happen during, immediately after, or a few days or weeks after surgery. Most side effects go away after surgery. Late side effects can occur months or years after surgery. Some side effects may last a long time or be permanent.

It is important to report side effects to the healthcare team.


A woman may experience pain, discomfort or tenderness around the incision and under the arm after breast surgery because of trauma to the tissue during surgery. It may take time for pain to go away after surgery. The intensity of the pain will depend on the procedure and how the woman heals and tolerates pain. Pain-relieving medications are used to control pain. Check with the doctor if pain does not go away or pain medicines do not relieve the pain.

Some women with breast cancer may have post-mastectomy pain syndrome as a long-term side effect of surgery.

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Wound infection

Some women may develop an infection in the wound after breast cancer surgery. This is not a common side effect, but it can potentially occur after any type of surgery. Sometimes tubes are placed into the wound to drain excess fluid. Antibiotics may be used to help prevent or treat an infection. Wound infections are a temporary side effect of surgery.

Tell your doctor or the healthcare team about signs of infection, such as redness, pus, foul-smelling drainage, fever and increased swelling or tenderness at the incision site.

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Bleeding or hemorrhage can occur if a blood vessel is not sealed off during surgery, or if the person has a blood clotting disorder. Nursing staff frequently check bandages and drains for heavy bleeding right after surgery. If bleeding occurs and is severe enough, the surgeon may have to take the person back to the operating room to find where bleeding is coming from and to stop it.

A small amount of bloody drainage may be expected after surgery. Report heavy bleeding to your doctor or the healthcare team.

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A seroma is a soft, puffy area of swelling caused by a collection of lymph fluid under the skin in the area of the surgical incision. Normally the lymph fluid flows through small tubes (lymph vessels) that connect the lymph nodes. During surgery, when the lymph vessels are cut or removed, the lymph fluid collects in the area. Seroma is a common potential side effect of breast surgery, especially mastectomy, and often happens after the surgical drains have been removed.

Treatment for a seroma may include draining the fluid with a needle and syringe. Some women may need to have the seroma drained several times. In rare situations, surgery may be necessary to remove a seroma.

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A hematoma is an abnormal collection of blood outside of the blood vessels. It is caused by blood leaking from the blood vessels that were cut during surgery. It is an uncommon side effect of breast cancer surgery.

A hematoma may cause pain, redness, skin discolouration and swelling in the area around the incision. Most hematomas will slowly disappear with time, but large hematomas may take several weeks or months to go away. Treatment may include compression applied to the area, or draining the collected blood with a needle and syringe. Pain-relieving medications may be used to control pain.

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Women will have fatigue for a period of time after breast surgery as the body recovers from surgery and the effects of general anaesthesia. Fatigue may last up to 2 months after surgery.

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Changes to arm and shoulder movement

Mastectomy can affect a woman’s ability to freely move her arm or shoulder through its complete range of motion. This can be caused by damage to the nerves and muscles in the chest and arm on the side of the surgery. Symptoms may include:

  • stiffness of the arm or shoulder
    • Weakness may also occur, but it is very rare.
  • limited arm movement
  • a feeling of tightness under the armpit and upper arm, and the sensation of a “cord” pulling in the muscles
    • This feeling often goes away 2–3 months after a mastectomy.

Rehabilitation exercises after breast surgery may help improve a woman’s range of motion after surgery and prevent long-term problems with movement.

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Breast cancer surgery will leave a scar on the breast or on the chest where the breast was removed during a mastectomy. These scars may be red and very noticeable in the months after surgery, but most will fade with time.

After the surgical incision has healed, the scar may be massaged to help prevent the tissue from attaching to the muscles of the chest. A physiotherapist or massage therapist can show a woman how to massage her mastectomy scar.

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Lymphedema is the swelling that occurs when lymph fluid builds up in the soft tissues of the limbs. It is caused by a problem in the movement of waste products (lymph fluidlymph fluidA clear, yellowish fluid that contains nutrients, lymphocytes (a type of white blood cell that fights germs, foreign substances or cancer cells) and antibodies. Lymph fluid circulates throughout the body in lymph vessels and bathes body tissues.) away from a limb (arm or leg). Lymphedema usually occurs in the arm or armpit (axilla) area after breast cancer surgery.

Lymphedema can occur right after surgery, or it may develop months or even years later. About 7% of people develop temporary lymphedema after axillary lymph node dissection (ALND) which goes away within a few months. About 5%–20% of women will develop permanent lymphedema. This usually occurs within 2 years after breast cancer treatment.

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Nerve damage

Nerves may be damaged or removed during breast cancer surgery. This can cause a loss of feeling (numbness) or changes in sensation in the upper arm, armpit, shoulder or chest. Nerve damage can appear long after surgery is over and may last a long time.

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Changes to sense of balance

A woman’s sense of balance may change after a mastectomy due to the uneven weight on her chest. Wearing a breast prosthesis may help a woman adjust to the change in her sense of balance.

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Changes to body image and self-esteem

Body image is a person’s perception of their own body. How people feel about or see themselves is called self-esteem. Breast cancer and its treatments can affect a woman’s body image and self-esteem.

Women may feel differently about their bodies and themselves as women after having breast cancer surgery. They may feel less like a woman or less feminine because they no longer have a breast or their body is scarred. These feelings may be a concern or cause of distress for some women.

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