What is Radiation Therapy?

High-energy X-rays, electrons or other sources of ionizing radiation are a cornerstone of cancer treatment. The goal of radiation therapy is to deliver a precise dose of radiation to a tumor while sparing healthy tissue. Radiation therapy may be combined with surgery, hormone therapy and chemotherapy to control or cure the disease. Linear accelerators, a treatment simulator and three-dimensional treatment planning make state-of the-art treatment available to patients.

When is Radiation Therapy used?

When a patient is first diagnosed with cancer, a "work-up" is done. The Medical Oncologist may order several tests to determine the extent or the stage of the disease. Some of these tests might include lab work, a CT scan, an MRI scan, Nuclear Medicine scans and X-Rays. The doctor can then use the results to determine the best course of treatment.

Cancer can be treated with Surgery, Chemotherapy, or Radiation Therapy. Many cancers, however, are successfully treated with a combination of two or all three modalities. Medical, surgical and radiation oncologists may consult with one another to determine the best treatment. Sometimes there may be several approaches for a particular cancer and a patient's physician may seek the input of a team of cancer specialists. The team is on a panel called "Tumor Board". The patient's records are presented, together with all the diagnostic studies and the team determines the best combination of treatments for that patient

How does Radiation Therapy work?

Radiation damages and kills cancer cells. Because cancer cells divide more rapidly than normal tissue, they are more sensitive to radiation. Normal cells, however, are more resistant and most will survive high doses of radiation. (The amount of radiation given is referred to as "dose" and the doctor prescribes the dose in units called Centigrays. Until recently, the dose unit was also called a "Rad").

Over the past fifty years' experience with treating patients and thirty years of clinical studies, the doctor knows how exactly much dose each specific cancer type should receive. This dose is given in small doses each day - over a period of 3-5 weeks, depending on the total dose the doctor wants to give. When a cancer cell has been damaged with radiation, it cannot repair itself, but normal cells can. This is why the radiation is given in small doses each day, over a period of several weeks. The normal cells get a chance to recover overnight while the cancer cells continue to get irradiated and eventually die.

What are the risks of Radiation Therapy?

At the time of consultation, the Radiation Oncologist explains the benefits and risks of treatment. The doctor will also discuss the possible side effects you might expect.

What are some side effects a patient can expect?

Each patient will respond differently to their treatments. The side effects can be general and/or site specific. Some patients have little or no side effects from their treatments.

Before your treatments start, you and your family or significant others who support you will be scheduled to meet with our Oncology Resource Nurse to offer you support and education about your radiation experience. She will discuss what you might expect from your treatments. She will also be available to you as a resource and support while you are on treatment. She helps the physician to monitor your course of treatment.

Fatigue is a common general side effect and it is usually not severe enough to disturb your daily routine. Site specific means that the body tissue the beam passes through will be affected. For instance, if we are treating your pelvis for a prostate cancer then the bladder and the bowel may have side effects.

Radiation side effects are cumulative, meaning it may take several weeks of treatment for symptoms to appear. Most side effects are temporary and you will be provided with symptom control when you need it from the doctor or nurse. Before you start treatment your doctor will discuss any possible long term side effects.

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