Surgery in cancer treatment
Surgery is a medical procedure to examine, remove or repair tissue. Surgery can be used in the following ways as part of a cancer treatment plan.
|Surgery for cancer|
Preventive, or prophylactic, surgery is used to prevent or lower the risk of developing certain types of cancer. It is done before cancer develops. The surgeon removes tissue that is not yet cancer but has a higher chance, or risk, of becoming cancer. For example, precancerous conditions are changes to cells that make them more likely to develop into cancer.
If you have an inherited condition that puts you at high risk for developing a certain type of cancer, your healthcare team may offer preventive surgery. The surgeon may remove large amounts of tissue or an entire organ to help lower your risk of developing that cancer. For example, some women who have a very high risk of developing breast cancer may choose to have one or both breasts removed before cancer develops (called a prophylactic mastectomy).
Doctors use different types of surgery to diagnose cancer. They can also use surgery to find out the stage of the cancer, which describes the amount of cancer in the body.
For example, surgery can be used to collect a sample of tissue from the body to be examined under a microscope (called a biopsy) to see if there are cancer cells. Also, when a tumour is removed with surgery, it can be examined to stage the cancer and help develop a treatment plan.
A pathologist will use a microscope to examine the biopsy sample or the tumour and surrounding tissues removed during surgery. A pathologist is a doctor who specializes in the causes and nature of disease. The pathologist will find out:
- the exact type of cancer
- the grade of the cancer
- if the cancer cells that are seen in any part of the tissue that is removed are also present in the edges of the tissue (called positive surgical margins)
- if any of the lymph nodes near the tumour have cancer in them
After getting the pathology report, doctors will decide if more treatment is needed and what type of treatments to offer.
The main goal of surgery to treat cancer is to completely remove the tumour or cancerous tissue from a specific place in the body. Surgery is most effective at completely removing cancer that is at an early stage, is only in the place where it started (localized) and hasn’t spread to other parts of the body.
Surgery may also be used to treat cancer that has spread from where it started (called the primary site, or primary tumour) to other parts of the body. The new tumour is called a metastasis, or secondary tumour.
During surgery to remove cancer, the surgeon will also remove a small amount of normal tissue all around the cancer (called the surgical margin). This is done to make sure that there are no cancer cells left behind. If cancer cells cannot be completely removed, they can cause the cancer to come back. The amount of normal tissue removed depends on the type and location of the tumour. Surgeons use normal vision and visual aids such as a microscope to make sure all the tissue affected by cancer along with a safety margin is removed.
Depending on the type of cancer, the surgeon may also remove lymph nodes close to the tumour. Surgery to remove lymph nodes is called a lymph node dissection. The lymph nodes are sent to a lab to be examined under a microscope to see if they have cancer cells in them. If the lymph nodes are not removed and they contain cancer cells, these cells may form new tumours or spread to other parts of the body.
Sometimes it may not be possible to remove all of the cancer because the:
- tumour is too big
- location of the cancer makes it difficult to remove without damaging nearby organs
- cancer is too small to be seen by the surgeon or found by tests
- person’s general health makes the surgery too risky
In some cases when all of the tumour can’t be removed, surgery is still done to remove as much of the cancerous tissue as possible (called debulking). Surgery to reduce the number of cancer cells in the body is called cytoreductive surgery. Cytoreductive surgery may make chemotherapy and radiation therapy more effective.
Surgeons try to avoid cutting into or across the tumour when they do surgery to remove a tumour or metastasis. This lowers the chance that the cancer cells will be scattered and spread to other structures. During a biopsy, surgeons also mark the track along which the biopsy was done. Then they remove the biopsy track during surgery to remove the cancer. Removing the biopsy track lowers the chance that any cancer cells are left behind.
Surgeons will try to do as little damage as possible during surgery to remove cancer. They will try to limit how much tissue they remove, or the extent of surgery, when possible. For example, they may use a biopsy to find the sentinel lymph node, which is the first lymph node that cancer is likely to spread to from the original, or primary, site. Finding no cancer cells in the sentinel lymph node means that surgeons can avoid removing all the lymph nodes in a certain area.
When possible, surgeons will use less invasive approaches that can be done through smaller incisions (cuts), such as laparoscopic surgery. They will also try to lessen or prevent side effects, or complications, of surgery by carefully repairing any tissue damaged during surgery. This includes sealing off blood vessels and avoiding injury to nearby organs.
Palliative surgery is surgery used to relieve symptoms and improve the quality of life. For example, surgery is sometimes used to create a bypass around a blocked, or obstructed, organ. It can also be used to relieve pain or pressure caused by a tumour.
The surgeon will discuss the risks and benefits of doing surgery, especially when the overall goal is to control symptoms and improve the quality of life rather than treat the disease.
In addition to removing the cancer with a small margin of normal tissue around it, surgeons may also remove other nearby normal structures. These structures can include muscles, nerves and lymph nodes. The surgeon may remove these structures even if there is no evidence that they contain cancer. The surgeon does this because research shows that removing nearby structures can lower the chance of many types of cancer coming back, or recurring.
The idea of removing nearby normal structures to lower the chance of recurrence is the basis for radical surgeries. A radical surgery removes the organ affected by cancer along with all the nearby tissues that could contain cancer. For example, a radical mastectomy removes all of the breast along with chest muscles and all of the lymph nodes under the arm. A radical neck dissection removes nearly all the lymph nodes on one side of the neck, as well as veins, muscles and nerves in the neck.
Reconstructive surgery may be used to repair tissue that is damaged by cancer or cancer treatments, including surgery to remove a tumour. It may be used to help part of the body work or look like it did before cancer or cancer treatments.
Surgeons can use different techniques to repair or rebuild structures in the body. These techniques include skin or tissue flaps and grafts, implants and prostheses.
Surgery may be used to provide direct access to a blood vessel so that you don’t have to feel the pain of needle sticks each time a drug or other treatment is given.
The surgeon may place an access, such as a central venous catheter, when they need to take blood samples or you need to get more than one dose of chemotherapy, antibiotics, blood products or intravenous (IV) nutrition. Find out more about central venous catheter.
Surgery may also be used to place a special pump that is used to deliver chemotherapy drugs.
Surgery may be used to help with body functions, such as breathing and getting enough nutrition.
A tracheostomy is surgery to make an opening into the trachea (windpipe) through the neck. It is used to place a breathing tube.
People who cannot eat or drink may have a surgical procedure called gastrostomy. This surgery makes an opening into the stomach through the abdominal wall so a tube can be placed directly into the stomach. The healthcare team can provide nutrition and liquids directly into the stomach through this tube.
As part of a cancer treatment plan, surgery may be used along with other cancer treatments, such as chemotherapy and radiation therapy.
Neoadjuvant therapy is treatment given to shrink a tumour before surgery. Chemotherapy, radiation therapy or both may be used as neoadjuvant therapy to shrink a tumour and make it easier to remove with surgery.
Adjuvant therapy is treatment given after surgery. Chemotherapy, radiation therapy or both may be used as adjuvant therapy to destroy cancer cells left behind after surgery and to lower the risk of cancer coming back, or recurring. These treatments may also be used to destroy any cancer cells that may have spread to other parts of the body. The timing of adjuvant therapy is based on your personal needs. Radiation therapy and chemotherapy are not used too soon after surgery because they can affect how a surgical wound heals.
Questions to ask about surgery
To make the decisions that are right for you, ask your healthcare team questions about surgery.
A description of a tumour that includes how different the cancer cells look from normal cells (differentiation), how quickly the cancer cells are growing and dividing, and how likely they are to spread.
Grades are based on different grading systems that are used for specific cancers. Some types of cancer do not have a specific grading system.
The process of examining and classifying tumours based on how cancer cells look and behave under the microscope is called grading.
I’m extremely grateful to the Canadian Cancer Society for funding my research with an Innovation Grant.
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