Radiation

What is it?

Almost everyone has had some experience with surgery or knows someone who has and just about everyone has had to take medications such as antibiotics to fight an infection, but very few people have had any experience personally or by someone close to them with radiation therapy. This guide to radiation therapy should help in understanding this form of treatment, which is widely used to treat cancer. Well over 50% of all cancer patients will require radiation treatments sometime in the course of their illness. It can be the only treatment or it can be combined with surgery and/or chemotherapy in a variety of ways. Radiation is also extremely effective to relieve pain or a blockage to swallowing and many other difficult problems associated with advanced cancer. It is one of the most important treatments to improve the quality of life of cancer patients.

It is the Radiation Oncologist who is the physician specialist who safely prescribes the use of therapeutic x-ray treatments to patients who have been diagnosed with a particular type of cancerous tumor or disease. Patients do not start their treatment of cancer by going directly to a Radiation Oncologist, but are referred by either a primary care physician or another physician specialist, such as a Medical Oncologist, a physician who delivers chemotherapy drugs, or a Surgeon, who has performed a biopsy or other surgery for the cancerous condition.

Radiation treatments can take a number of different forms. Most frequently, radiation is delivered by an x-ray machine called a linear accelerator or a machine which has a source of radioactive cobalt. A course of treatment usually requires a number of weeks. Radiation is delivered Monday through Friday, usually on a daily basis. A second way to use radiation is to insert radioactive material directly into a cancerous growth. This is called brachytherapy. The radioactive material may be removed after a period of time to deliver a specified dose of radiation. Sometimes, radioactive sources can be inserted into the tumor and left there permanently. Permanent implants are frequently used in the treatment of prostate cancer and removable radioactive source treatment is frequently used for cancers of the uterus or cervix.

How is the treatment administered?

The Radiation Therapist administers the daily treatments. S/he is board certified, licensed, and registered in the field of radiation therapy. The therapist walks the patient into the treatment room and helps the patient to assume the treatment position on the treatment table. The therapist lines up the treatment beams with the use of laser beams, which shine on the patient's skin and are lined up with the tattoo to guarantee that the exact same location will be irradiated in each treatment session. Once the treatment beams are set, the patient is asked to hold still, relax, and breathe normally. The therapist leaves the treatment room to deliver the treatment. The therapist will watch the patients on a monitor during treatment. The patient can be seen and heard at all times. The treatment can be interrupted at any time to allow the therapist to check the patient and resume the treatment if necessary.

Verification films are taken regularly during the course of treatment for quality assurance purposes. Since the complex treatment program requires computer assistance for the movement of the treatment machine, it is important that this is verified during the course of treatment. Modern radiotherapy equipment is highly sophisticated but small problems can occur, which the Radiation Therapist and the Radiation Oncologist will constantly look for and correct. The Radiation Therapist is responsible for the safe delivery of radiation treatments. (S)he records the daily doses of radiation as prescribed by the Radiation Oncologist. The therapist monitors the side effects and reports any changes or problems to the physicians, nurses, or physics staff. Due to the significant amount of time that the patient and the therapist spend together, a special bond often forms between them.

Do the treatments hurt?

No. Treatments are painless. The patient does not see or feel anything. The patient may hear a hum or other mechanical noises when the therapy machine is in operation. The x-ray treatment itself is not difficult. Some patients do experience side effects. Different courses of treatment to different parts of the body have different side effects in some but not all of the patients. In fact, most patients will proceed through an entire course of treatment with no side effects whatsoever. However, patients are given instructions and medications to help ease any discomfort, which may occur.

Glossary:

• Brachytherapy - In this procedure, the doctor surgically implants radioactive sources into the site of the cancer. Over a period of time, these sources slowly release radiation killing only the cancerous cells.
  
  
• Biopsy - A biopsy is a procedure in which a doctor surgically removes a piece of a tumor. Once the section is removed, it is analyzed in a laboratory to determine if the tissue contains cancer.
  
  
• Carcinoma of the Cervix - Cervical cancer is cancer of the end of the uterus that comes into the vaginal canal in a woman.
  
  
• Cobalt Apparatus - A cobalt apparatus is a type of machine used to administer radiation treatment. This machine uses gamma rays emitted by cobalt, a radioactive material. The gamma rays are then aimed at the site of the tumor.
  
  
• Computer Tomography (CT) Scan - CT scans use computer imaging to create a three dimensional image of the area being viewed. This procedure is helpful in locating and diagnosing tumors and other abnormalities.
  
  
• External Beam Therapy (EBT) - EBT is a method of applying radiation to a tumor from the outside of the body. X-rays are aimed at the site of the tumor, and the concentration of radiation works to kill cancer cells. It is most often done through the use of a linear accelerator or cobalt apparatus.
  
  
• High Dose Radiation Therapy (HDR) - Using special catheters inserted into a tumor a source of radiation is moved into the area. The radioactive source contains a highly radioactive material and delivers a high dose of radiation in a short period of time under computer control. The source and the tubes are then removed.
  
  
• Intensity-Modulated Radiation Therapy (IMRT) - IMRT uses computer-imaging technology to guide a very concentrated stream of radiation directly to a tumor or to part of a tumor. Because IMRT directs the radiation directly to the tumor, a higher dose of radiation can often be used without risk of exposure to the surrounding healthy tissue. This procedure uses a linear accelerator specially adapted for this purpose.
  
  
• Linear Accelerator - A linear accelerator speeds up electrons in a special wave guide and directs them to hit a metal target which produces high energy X-rays. This machine requires the patient to lie still while a portion of the machine rotates around the patient. The procedure is painless, but it does require patience on the part of the patient.
  
  
• Ortho Voltage X-Ray Equipment - This device is a machine that produces low energy X-rays which can be focused to irradiate a tumor.
  
  
• Permanent Implant - During brachytherapy the implanted radioactive sources can sometimes remain in the body after the radiation has worn out with no other effects. After the radiation oncologist implants the radioactive sources, the patient will not have to have them removed. This is often used in treatment of prostate cancer.
  
  
• Radiation Oncologist - A radiation oncologist is a doctor who specializes in treating cancer and oversees the care of patients going through radiation therapy. These doctors are trained in many specialized treatment methods and they ensure that the proper treatment is provided in a safe manner.
  
  
• Radiation Oncology Nurse - Radiation oncology nurses play an important role in caring for patients before, during, and after treatment. These nurses are responsible for preparing the patient for the treatment, discussing the patient's concerns, and providing education about after care, they may prescribe medications to alleviate symptoms, which can arise during radiation treatment.
  
  
• Radiation Physicist - Radiation physicists are responsible for calculating and monitoring the amount of radiation given off by the various types of treatment machines. These individuals ensure the accuracy and dosage of the treatment, using highly sophisticated computer programs, they are responsible for calibrating the radiation equipment so that the exact dose will be delivered.
  
  
• Radiation Therapist - Radiation therapists are specially trained to deliver the treatment as directed by the radiation oncologist. They are responsible for keeping accurate records of the dose of radiation the patient has received at each session of radiation treatments.
  
  
• Removable Implant - Removable implants are placed in the body during brachytherapy and need to be taken out once the pre-calculated dose of radiation has been delivered. For this procedure, the patient will need to remain in the hospital or other protected area and can then go home.
  
  
• Simulation - Simulation is another term for "Treatment Planning." Before simulation, the patient will sit down with the radiation oncologist and discuss the course of action that will be used to treat the diagnosed cancer. Then the patient will be placed in the position of treatment and X-rays will be taken to ensure that the appropriate area requiring radiation will be entirely included in the fields of treatment. Permanent tattoo marks (the size of a freckle) will than be made to direct the position of treatment each and every time treatment is done.
  
  
• Therapeutic X-Ray - Therapeutic X-rays are given to treat a patient's disease, as opposed to diagnostic X-rays that are used to identify or diagnose a disease.
  
  
• Treatment Plan - One of the main goals of radiation therapy is to remove as much as the tumor as possible while keeping the surrounding tissue healthy. A treatment plan seeks to attain both of these goals. Using highly sophisticated computer technology, the distribution of energy in the tumor is calculated and displayed on the screen and also printed for a permanent record. Adjustments to maximize the radiation on the tumor and spare the normal surrounding tissue is done before any treatment is given.
  
  
• Verification Films - Verification films are taken during treatment to provide a clear picture of exactly where the planned X-ray are going so that the tumor will get the dose required and the normal tissue will be out of the high dose volume. These are used by the staff for quality assurance throughout the course of treatment.
  

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