Cancer Treatments

Cancer occurs when cells in a part of the body start to grow out of control. (Read about "Cancer: What It Is") In treating cancer, the ultimate goal is often to cure the disease or send it into remission, in which all the cancer cells disappear. If the cancer has spread to the point that a cure is not possible, treatment can still help relieve symptoms and extend life, both in terms of time and quality.

Staging

In determining a course of treatment, a doctor must first stage the cancer, in other words, determine how much cancer is present, where it is, and whether it has spread to either nearby regions, to lymph nodes, or if it has metastasized or spread to distant areas of the body. Staging is the term used to describe the extent or severity of an individual's cancer. A cancer's stage depends on different factors, including its location, its size, whether lymph nodes have been affected and whether or not the cancer has spread. (Read about "The Lymph System")

The National Cancer Institute (NCI) says different tests can be used to help determine a cancer's stage. These include blood and urine tests; imaging tests such as x-rays, CT scan, MRI, PET and ultrasound (Read about "X-rays" "CT Scan - Computerized Tomography" "MRI - Magnetic Resonance Imaging" "PET - Positron Emission Tomography" "Ultrasound Imaging"); pathology reports from the biopsy; and surgical reports. Knowing a cancer's stage helps to determine the best way to treat it. For example, the treatment for very early stage cervical cancer (Read about "Cervical Cancer") may be surgery alone, while a more advanced stage of cervical cancer may require radiation therapy or a combination of radiation therapy and chemotherapy. (Read about "Radiation Therapy")

Tumor grade is another factor that doctors consider when they develop a treatment plan, especially for certain types of cancers, such as breast and prostate cancer. (Read about "Breast Cancer" "The Prostate") Tumor grade refers to the degree of abnormality of cancer cells compared with normal cells. Generally, speaking, according to NCI, lower grade tumors are considered less aggressive than higher grade tumors.

NCI says that depending on the stage, grade and other factors, treatment options can include any of the following, alone or in combination:

Surgery

Surgery can be used in the diagnosis and staging of cancer. Surgery can also be preventive, for example, when it's used to remove an organ or tissue that may be pre-cancerous or likely to develop cancer at a later time. And surgery is also used as primary treatment for cancerous tumors. The success of surgery, as with other treatments, can depend on how early the cancer is caught, which is why cancer screenings and early detection have such life-saving potential.

The American Cancer Society (ACS) says different types of surgery can be used in the treatment of cancer:

• Conventional surgery involves the use of scalpels and other surgical instruments to remove, repair or replace the parts of the body affected by the cancer.
• Laparoscopic surgery uses a long, flexible tube that is placed through a small incision, or inserted through an opening in the body, to view the inside of the body. (Read about "Endoscopy")
• Cryosurgery is a process in which abnormal cells are killed by freezing. Originally used to treat external tumors, such as those on the skin, NCI says cryosurgery is now also being used as a treatment for tumors that occur inside the body.
• Electrosurgery uses high-frequency electrical current.
• Laser surgery involves the use of high-intensity light. NCI says this technique is often used to relieve symptoms of cancer such as bleeding or obstruction, and it may also be used to treat cancer by shrinking or destroying tumors.
• Mohs surgery is a process in which cancerous tissue is shaved off one layer at a time.

Depending on the type of surgery, and the extent of the cancer, there can be a number of side effects, including pain and tenderness in the area of the operation. Other side effects depend on the type of surgery and the type of cancer, for example, surgery for colorectal cancer may also cause temporary constipation or diarrhea. (Read about "Constipation" "Diarrhea") Surgery that involves removal of lymph nodes in the underarm, groin or pelvic regions can result in a swelling in specific areas of the body, usually an arm or leg. This swelling is called lymphedema, and NCI calls it a common complication of cancer and cancer treatment. (Read about lymphedema in "The Lymph System") Patients who anticipate cancer surgery can ask their doctors how the surgery will specifically affect them. (Read about "Learn About Your Procedure" "At the Hospital: For Patients" "Anesthesia")

Chemotherapy

Chemotherapy is the use of anti-cancer drugs to kill cancer cells. Chemotherapy may also be used to destroy any cancerous cells that remain in the body after surgery, as well as to relieve symptoms or control tumor growth.

In chemotherapy, the anti-cancer drugs are often given either by injection directly into a vein (IV) or by means of a catheter, which is a thin tube that is placed into a large vein and remains there as long as it is needed. Infusion therapy is the term often used to describe the administration of medication - such as chemotherapy drugs - through a needle or catheter. Some anti-cancer drugs are given in the form of a pill. (Read about "Infusion Therapy")

In whatever way the drugs are administered, chemotherapy is considered a systemic approach, which means that once the drugs enter the bloodstream, they can affect cells throughout the body, not just in the area where the cancer is located.

Since chemotherapy drugs target rapidly growing cells such as cancer cells, ACS says they also damage other fast growing cells. The cells lining the mouth and intestines grow rapidly and are likely to be affected by chemotherapy. As a result, common side effects of chemotherapy can include nausea and vomiting, mouth sores, diarrhea and fatigue. (Read about "Oral Health" "Diarrhea") Hair loss (alopecia) is another common side effect of chemotherapy, but NCI says not all drugs cause hair loss. Your doctor can tell you if hair loss might occur with the drug or drugs you are taking.

ACS says people being treated with chemotherapy may also have a higher risk of infection (from low white blood cell counts), may bruise or bleed easily (from low blood platelets), and tire easily (from low red blood cell counts). Chemotherapy can reduce the bone marrow's ability to make red blood cells, which carry oxygen to all parts of your body. When there are too few red blood cells, body tissues do not get enough oxygen to do their work. This is called anemia, and can lead to fatigue, weakness and shortness of breath. (Read about "Anemia")

Radiation therapy

Whereas chemotherapy affects the entire body, radiation therapy is a local therapy (Read about "Radiation Therapy"), meaning that it affects cells primarily in the treated area. Radiation therapy, also called radiotherapy, involves the use of penetrating beams of particles - such as x-rays, gamma rays or charged particles - to kill cells that divide rapidly. Radiation can destroy tumors and cancerous cells, but can also affect non-cancerous cells nearby. New techniques let physicians more accurately pinpoint the location of a tumor, and thus deliver greater amounts of radiation to the tumor while minimizing the dose to the healthy tissue that surrounds it. Imaging techniques such as CT scans are employed prior to and sometimes during the radiation treatment to more precisely target the tumor. (Read about "CT Scan - Computerized Tomography") A radiation oncologist may also use magnetic resonance imaging (MRI), positron emission tomography (PET), or ultrasound to plan treatment. (Read about "MRI - Magnetic Resonance Imaging" "PET - Positron Emission Tomography" "Ultrasound Imaging")

Radiation may be used before surgery to shrink a tumor so that it is easier to remove. Radiation can also be used after surgery to destroy any cancer cells that remain in the treated area. Radiation may also be administered in combination with chemotherapy. In addition, it can be used to relieve symptoms.

NCI says some of the different types of radiation include:

• External-beam radiation therapy - This is radiation that comes from a machine outside the body. Patients can receive external-beam radiation therapy in daily treatment sessions over the course of several weeks. Different types of external-beam radiation include:
  • 3-dimensional conformal radiation therapy (3D-CRT) - 3D-CRT uses computer software to deliver radiation to precisely shaped target areas.
  • Intensity-modulated radiation therapy (IMRT) - IMRT uses tiny radiation beam-shaping devices to deliver radiation, allowing different areas of a tumor or nearby tissues to receive different doses of radiation.
  • Image-guided radiation therapy (IGRT) - In IGRT, repeated imaging scans are performed during treatment, to identify changes in a tumor's size and location.
  • Tomotherapy - This is a type of image-guided IMRT.
  • Stereotactic radiosurgery - Stereotactic radiosurgery (SRS) can deliver one or more high doses of radiation to a small tumor, in the brain or spinal cord. It uses image-guided tumor targeting and patient positioning to deliver as high a dose of radiation as can be given. It is not uncommon for hospitals to refer to their SRS system by brand name.
  • Stereotactic body radiation therapy - SBRT uses image-guided tumor targeting to deliver high-dose radiation to a tumor in the body. It is not uncommon for hospitals to refer to their SBRT system by brand name.
  • Proton therapy - External-beam radiation therapy can be delivered by proton beams. Protons are a type of charged particle. Proton beams differ from x-rays or gamma rays in that they deliver much of their energy at the end of their path, depositing less energy along the way.
• Internal radiation therapy / brachytherapy - In brachytherapy, the radioactive material is sealed in tiny pellets or "seeds." These seeds are placed inside the patient. In interstitial brachytherapy, the radiation source is placed within the tumor. In intracavitary brachytherapy, the radiation source is placed within a surgical cavity or a body cavity, such as the chest cavity, near to the tumor. The placement of the radioactive material can be temporary or permanent.
• Systemic radiation therapy - This involves a radioactive substance, given by mouth or into a vein, that travels in the blood to tissues throughout the body.
• Intraoperative radiotherapy (IORT) - This is the use of a single high dose of radiation at the time of surgery. The radiation is delivered to the targeted area, such as a tumor, while that area is exposed during surgery.

Side effects of radiation therapy depend mainly on the treatment dose and the part of the body that is treated. Common side effects can include fatigue, skin changes at the site where the treatment is given, lymphedema or swelling in an arm or leg (Read about lymphedema in "The Lymph System"), inflammation of the mucous membranes, loss of appetite, nausea and diarrhea. (Read about "Diarrhea")

Biological therapy

Biological therapy, also called immunotherapy, uses the body's immune system (Read about "The Immune System") to fight cancer. (For specific terms, read "Immune System Glossary") In a healthy body, the immune system can be capable of finding and fighting cancer cells. NCI says biological therapies are used to repair, stimulate or enhance the immune system's natural anticancer function.

NCI says examples of different classes of agents that can be used in this type of therapy include:

• Nonspecific immunomodulating agents, which are substances that stimulate or indirectly augment the immune system.
• Biological response modifiers (BRMs), which alter the interaction between the body's immune defenses and cancer cells to boost, direct, or restore the body's ability to fight the disease.
• Interferons, which can improve the way a cancer patient's immune system acts against cancer cells.
• Monoclonal antibodies, which are antibodies produced by a single type of cell and are specific for a particular antigen.

Biological therapy may be given after surgery, either alone or in combination with chemotherapy or radiation treatment. Most biological treatments are given by injection into a vein (IV). Biological therapy may cause side effects that vary with the specific type of treatment. Often, treatments cause flu-like symptoms, such as chills, fever, weakness and nausea.

Hormonal therapy

Hormonal therapy can also be used for certain cancers. For example, estrogen promotes the growth of about two thirds of breast cancers, according to ACS. Because of this, blocking the effect of estrogen or lowering estrogen levels is used to treat some types of breast cancer. Drugs - such as anti-estrogen drugs or aromatase inhibitors - are one option for this; another is surgical removal of the ovaries.

Hormonal or androgen deprivation therapy is also used in some cases of prostate cancer. NCI says the advantages of certain hormonal therapies can include immediacy and ease of the procedure; disadvantages can include loss of libido and an increased risk of osteoporosis. (Read about "Osteoporosis")

Targeted therapy

Targeted cancer therapies use drugs that block the growth and spread of cancer. NCI says targeted cancer therapies interfere with cancer cell growth and division in different ways and at different points during the development, growth and spread of cancer. Many of these therapies focus on proteins that are involved in the signals cells use to communicate with each other. By blocking the signals that tell cancer cells to grow and divide uncontrollably, targeted cancer therapies can help to stop the growth and division of cancer cells. Because they focus on targeted molecules, NCI says targeted cancer therapies may be more effective, as well as less harmful to normal cells.

Lasers and photodynamic therapy

Photodynamic therapy (PDT) combines a drug with a certain type of light. When the drug, called a photosensitizer, is exposed to a specific wavelength of light, it produces a form of oxygen that kills nearby cancer cells. NCI says PDT is usually used to treat tumors on or just under the skin or on the lining of internal organs or cavities. The light used for PDT can come from a laser or other sources of light. Lasers can also be used alone. NCI says laser light is a light of such high intensity and narrow beam that it can be used to do precise surgery to remove cancer or precancerous growths or to relieve symptoms of cancer. Laser therapy is used most often to treat cancers on the surface of the body or the lining of internal organs. In the latter cases, it is often directed through a thin tube called an endoscope. (Read about "Endoscopy")

For many cancer patients, a combination of treatments may be used. In all forms of cancer treatment, it's important for patients to report any severe side effects to their doctor. It's also important to maintain regular follow-up care and check-ups.

More Cancer Information:

    Cancer Check-ups

    Cancer Support

    Reduce Cancer Risks

    Cancer Glossary

For a list of individual types of cancer, see Cancer: What It Is

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