Lung Cancer 101
Understanding the Different Types of Treatment
After a person receives a lung cancer diagnosis, the physician and the individual will choose the most appropriate treatment option, based on the type and stage of that person’s cancer and his or her overall health. The oncologist will also consider what symptoms the person is having, his or her ability to carry on normal daily activities and need for bed rest, and the individual’s opinion about quality of life. All of these are important considerations in choosing the best treatments. The main treatment options for lung cancer are surgery, radiation, and chemotherapy. New treatments are also showing promise.
Surgery Because surgery actually removes a tumor and nearby lymph nodes, it offers the greatest chance for significant survival for some types of lung cancer. This is especially true for early stage cancers that have not spread to other parts of the body. Some people may undergo surgery during the course of their diagnosis and treatment. Surgery may be the first step in treating lung cancer, or it may be considered after chemotherapy and radiation.
A thoracic surgeon is specially trained to perform lung cancer surgery. During surgery, the surgeon will remove the tumor and a surrounding margin of tissue. This margin will be evaluated under a microscope to see if it contains any cancer cells. A negative margin means that no cancer is found in the tissue surrounding the tumor. A positive margin may require the surgeon to remove more of the lung tissue until a clear margin can be identified.
Surgery may be the first step in treating lung cancer, or it may be considered after chemotherapy and radiation.
There are two types of surgery for lung cancer:
- Curative surgery This is the removal of a tumor when it appears to be confined to one area, which means an early-stage cancer. This type of surgery aims to completely remove the cancerous tumor, and may include removal of a wedge, a lobe, or an entire lung.
- Palliative surgery The goal of this surgery is to make the person more comfortable, for example, the opening of an airway or laser surgery to remove an obstruction.
As with any type of treatment, there are certain side effects associated with surgery. These side effects may occur during or after the procedure and will vary depending on the type of surgery. After surgery, potential side effects include pain and infections.
Chemotherapy uses strong chemicals or drugs to kill cancer cells, stop their reproduction, or slow their growth. There are many types of chemotherapy drugs, and they may be given in combination with each other and in combination with surgery and radiation. A medical oncologist prescribes chemotherapy, but it may be given by an oncology nurse.
Even though some chemotherapy drugs may be taken orally in tablet, capsule, or liquid form, most chemotherapy for lung cancer is given intravenously. Chemotherapy is called systemic therapy because it treats the entire body, or system. Chemotherapy can kill cancer cells that have metastasized from the original tumor because it travels through the blood system to all parts of the body.
The amount of chemotherapy a person receives depends on the type of cancer, the specific drugs, and the person’s overall response to treatment. This therapy may be given daily, weekly, or monthly, and it can continue for months or possibly years. Some drugs may be given in cycles, with rest periods between treatments to allow the body to recover.
Chemotherapy may be referred to as adjuvant therapy because it is given in addition to surgery or radiation. When it is used as adjuvant therapy, it is intended to reduce the risk of a recurrence by traveling throughout the body and killing whatever cancer cells remain after surgery. Neoadjuvant therapy is chemotherapy that is given prior to any surgery. The goal of neoadjuvant therapy is to shrink the lung tumor so that it can more successfully be removed.
Chemotherapy may be given daily, weekly, or monthly, and it can continue for months or possibly years.
Chemotherapeutic drugs affect normal cells, too. Particularly, cells that are rapidly dividing will take up chemotherapy and die. Examples of these include cells lining the gastrointestinal tract, those in the bone marrow, and those making up hair follicles. The most common side effects from chemotherapy, such as nausea and vomiting, a weakened immune system, and hair loss, are due to these normal cells being damaged during chemotherapy. Fortunately, almost all side effects from chemotherapy are temporary and gradually disappear after treatment is finished.
Side effects of chemotherapy vary depending on the type of chemotherapy used and how the individual responds to it. Some drugs are known to have more side effects than others do. Your doctor will be able to explain the different drugs, their side effects, and why different drugs are recommended for different uses. You should discuss any side effects with your doctor because there are many medicines available to help alleviate them. Some common side effects of chemotherapy include nausea and vomiting, hair loss, fatigue, infections, bleeding, mouth sores, loss of appetite, and diarrhea.
Radiation therapy (also called radiotherapy) may be effective for the treatment of lung cancer. It uses high-energy rays, similar to X-rays but stronger, to kill or shrink cancer cells. Usually, lung cancers are treated from an external source of energy. However, research is under way to study the use of implanted radioactive seeds into or near the lung cancer. This type of radiotherapy, called brachytherapy, has been successfully used in the treatment of prostate cancer.
Radiation oncologists are the physicians who administer radiation. Radiation-delivery machines are designed to focus the radiation in precise locations in the body for exact periods. This precision reduces the risk of damage to normal tissue surrounding the tumor. However, even with such advances and the use of shields to protect the parts of the body that do not require treatment, some healthy cells will be damaged by the radiation.
Radiation therapy is usually spaced over a number of weeks or months because the doses needed to kill cancer cells cannot be given all at once. The number of treatments a person receives depends on the type and extent of the tumor, as well as the radiation dosage and how the person is affected by the treatment.
External beam radiation (given from a source that is external, or outside of the body) may be used as the main treatment for lung cancer for some people. For other people, radiation may be used after surgery to kill remaining cancer cells or to treat metastases.
Depending on the specific regimen, side effects from radiation therapy may vary. However, a few common side effects include fatigue, hair loss, and skin reactions.
As scientists learn more about how the genetic changes in cancer cells occur, they are working to design ways to correct those changes.
New Treatments Recently, there has been an increase in new treatment advances for lung cancer. Some of these advances are still undergoing research in clinical trials, while others have been approved and are being used for treatment of people with cancer. The following are some of these new treatments:
- Chemotherapy regimens Different combinations of existing chemotherapy drugs are being explored. Oncologists are constantly refining the way lung cancer is treated. Clinical trials often test new combinations of drugs to see if they will work better than what is currently the standard of care.
- Targeted therapies These therapies, which include monoclonal antibodies, anti-angiogenesis drugs, and growth factor inhibitors, are designed to treat only the cancer cells, thus sparing normal cells from damage. Many targeted therapies are being researched, and some are in active use.
- Monoclonal antibodies These bioengineered molecules contain one part that can home in on the cancer cells coupled with another part that may contain a drug or radiation. Therefore, when the monoclonal antibodies are administered, they travel to the site of the cancer and release their drug or radiation. Monoclonal antibodies are designed to target only cancer cells, thus reducing side effects.
- Anti-angiogenesis agents Angiogenesis is the process that tumors use to make new blood supplies, which enable the tumors to grow. Drugs that counteract this ability are called antiangiogenesis agents. They are a very promising area of cancer therapy.
- Growth factor inhibitors Cancer cells can grow so quickly because they often manufacture substances (called growth factors) that encourage their own growth. Specially designed drugs have been created that block the effects of the growth factors, which means the cancer cells can no longer grow.
- Photodynamic therapy The use of light (photo) to shine on cancer tissue and activate drugs is another promising area of research.
- Lung cancer vaccines Vaccines use the body’s immune system to fight diseases by engineering cancer cells so that they are no longer cancerous but still contain components that the immune system will recognize as foreign. The theory is that by introducing small amounts of the vaccine, the body’s immune system will mount a defense against it. Unlike childhood vaccinations, cancer vaccines are promising not to prevent the primary occurrence of cancer, but to treat cancer that already exists.
- Gene therapy As scientists learn more about how the genetic changes in cancer cells occur, they are working to design ways to correct those changes. The area of gene therapy, in which normal copies of damaged genes are inserted into cells, has much promise but is still largely experimental.
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Excerpted with permission from lungcancer.org, copyright © 2009 by CancerCare.
For more information about lung cancer and free support services for anyone affected by cancer, call CancerCare at (800) 813-HOPE or visit LungCancer.org.
This article was published in Coping® with Cancer magazine, November/December 2009.