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Breast cancer

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Surgery for breast cancer

Surgery is the primary treatment for breast cancer. Most women with breast cancer will have some type of breast surgery.

Surgery is used to:

  • potentially cure the cancer by completely removing the tumour
  • determine if the cancer has spread to the lymph nodes
  • treat a local recurrence of breast cancer

The type of surgery done depends mainly on:

  • the size and location of the breast tumour
  • the size of the breast itself
  • how many areas of cancer there are in the same breast (multifocal disease)
  • whether the cancer has spread to the lymph nodes, and the number of lymph nodes involved
  • the woman’s overall health
  • factors like the woman’s choice of surgery or her ability to travel for treatment
  • prior treatments for breast cancer

The types of surgery for breast cancer are:

  • breast-conserving surgery (BCS)
    • This type of surgery may also be called lumpectomy.
  • mastectomy
  • sentinel lymph node biopsy
  • axillary lymph node dissection

The surgeon will discuss possible surgical options and the risks and benefits of each type of procedure. In most cases, a woman will be given the choice between breast-conserving surgery and mastectomy.

Breast-conserving surgery

Breast-conserving surgery (BCS) is an operation that removes the tumour and some of the healthy tissue around it. This type of surgery allows a woman to keep, or conserve, as much of her breast as possible. Often the breast is a little different after BCS, but the changes are often not very noticeable. After surgery, the breast is smaller, slightly different in shape and slightly firmer. In most cases, BCS will be followed by radiation therapy.

BCS is considered an option if:

  • Compared to the size of the breast, the tumour is small enough that the surgeon can safely remove all the cancer and a margin of healthy tissue around it.
    • In some very select situations, chemotherapy is given before surgery to shrink a large breast tumour enough to allow BCS to be done instead of a mastectomy.
  • The woman wants to keep as much of her breast as possible.

Procedure for breast-conserving surgery

BCS is most frequently done using general anaesthetic. A cut (incision) is made over or near the breast tumour and the lump or abnormality is removed, along with a margin of healthy tissue.

The skin is closed with stitches (sutures) or special staples and a bandage or dressing covers the wound. Stitches or staples are removed once the incision has healed. Some stitches dissolve on their own.

The removed breast tissue is sent to a laboratory. A pathologist (a doctor who specializes in the causes and nature of disease) examines the edges of the tissue sample for cancer cells.

  • If no cancer cells are found in the edges of the removed tissue, it is reported as clear or negative margins.
  • If cancer cells are found, it is reported as positive margins.
    • With positive margins, another operation will need to be done. It will either be another BCS to remove more breast tissue from the same surgical site or a mastectomy. This second operation is needed because cancer left behind after BCS can lead to a recurrence.

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A mastectomy is an operation that removes the entire breast. Reconstructive surgery may be done at the same time as a mastectomy or later as a separate surgery.

Mastectomy may be recommended as a treatment option in some cases if:

  • The woman prefers to have a mastectomy.
  • The area of cancer is large compared to the size of the breast.
  • The tumour has a shape or is in a location that would leave little breast tissue or a deformed breast if BCS was done.
  • The cancer is in more than one area of the breast.
  • BCS has been done and the tissue removed has cancer cells (positive margins).
  • The woman has inflammatory breast cancer.
  • The woman has already had radiation therapy to the breast.
  • The woman cannot or does not want to have radiation therapy after BCS because:
    • A disability or condition (such as arthritis) prevents her from lying flat or stretching out the arm during radiation treatment.
    • She has a connective tissue disease called systemic lupus erythematosus (the immune system attacks the body’s own tissue and organs) or scleroderma (thickening and hardening of the skin). These diseases make radiation treatment unsuitable because there is an increased chance of side effects.
    • Some women may find it too difficult to go for daily radiation treatments that are needed after BCS or do not want to have to deal with the possible side effects from radiation therapy.
    • A pregnant woman may be advised to have a mastectomy because they cannot have radiation therapy to treat breast cancer during pregnancy.

Types of mastectomy

The 3 different types of mastectomy are:

Total mastectomy

A total mastectomy (simple mastectomy) removes the entire breast, the nipple and the lining over the chest muscles (pectoral fascia). The lymph nodes, nerves and muscle in the chest are left in place.

A total mastectomy may be done if:

  • The breast cancer is very early stage (non-invasive, in situ, stage 0) and has not spread to the surrounding lymph nodes.
  • The woman has a high risk of developing breast cancer and wishes to reduce her risk by removing her breasts (prophylactic mastectomy).

If breast reconstruction is being considered at the same time as the surgery to remove the cancer, a skin-sparing mastectomy may be an option for some women. A skin-sparing mastectomy is like a total mastectomy except that it preserves the skin overlying the breast. This allows for breast reconstruction to take place with minimal visible scarring.

Modified radical mastectomy

A modified radical mastectomy removes the entire breast, the nipple, most or all of the lymph nodes in the armpit and the lining over the chest muscles (pectoral fascia). Nerves and muscles are usually left in place.

Radical mastectomy

A radical mastectomy removes the entire breast, the nipple, all of the lymph nodes in the armpit and the muscles in the chest. This type of mastectomy is seldom done anymore. It may be done if a woman has a recurrence of breast cancer in the chest muscles.

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Procedure for mastectomy

Mastectomy is done under general anesthetic. One or more drains (plastic or rubber tubes) may be put into the area where the breast was or under the arm to remove blood and lymph fluid that collects during healing. The skin is closed with stitches (sutures) or special staples and a bandage or dressing covers the wound (incision).

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Sentinel lymph node biopsy (SLNB)

Sentinel lymph node biopsy (SLNB) is the removal of the sentinel node to see if it contains cancer. The sentinel lymph node is the first lymph nodelymph nodeA small, bean-shaped mass of lymphatic tissue along lymph vessels (tubes through which lymph fluid travels in the body). Lymph nodes store lymphocytes (a type of white blood cell that fights germs, foreign substances or cancer cells) and filters bacteria and foreign substances (including cancer cell in a chain or cluster of lymph nodes that receives lymph fluid from the area around a tumour. Cancer cells will most likely spread to these lymph nodes. There may be more than one sentinel node, depending on the drainage route of the lymph vessels around the tumour.

SLNB may be an alternative procedure to axillary lymph node dissection (ALND) for women with early stage breast cancer. If the sentinel lymph node contains cancer, in most cases the surgeon will do an ALND procedure. In some women, an ALND may not be offered, but this decision is made depending on a woman’s individual situation.

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Axillary lymph node dissection (ALND)

Axillary lymph node dissection (ALND) is a surgical procedure to remove the lymph nodes from under the arm (the axilla). It is used to diagnose and stage breast cancer.

ALND is done at the same time as a mastectomy. With BCS, it may be done at the same time through a separate incision under the arm, or as a separate operation at a later time.

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After breast cancer surgery

Breast cancer surgery may be done as an outpatient procedure, or a hospital stay may be needed. The length of stay in the hospital depends on the type of surgery and other factors, such as the woman’s general health and how she feels after the surgery.

Women may be sent home with the drains that were put in during surgery. The healthcare team will give instructions on how to care for the incision and the drains at home.

Drains are removed when there is little drainage from them. Stitches or staples are removed once the incision has healed. Some stitches dissolve on their own.

See a list of questions to ask your doctor about surgery.

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