Radiation Oncology
Radiation is a vital part of the comprehensive cancer treatment that people receive at Methodist. Patients have access to some of the latest advances in treatment, including a new therapy for cancer of the lungs, cervix, vagina and uterus called high dose rate brachytherapy.
Basic services include:
- Treatment that uses advanced linear accelerators to direct x-rays and electron beams into cancerous cells.
- Procedures that precisely target cancer cells with radiation, using a state-of-the-art multi-leaf collimator. This computer-controlled device contains 120 mechanical "leaves" that move and shape a beam of radiation to match the three-dimensional shape of a patient's tumor. This technology is especially effective for small, irregularly shaped cancers in locations that are difficult to reach, otherwise.
- Radioiodine therapy (131I) that treats people with thyroid cancer. The thyroid gland concentrates iodine from food and uses it for normal functioning. Consequently, patients can be treated with iodine combined with a radioactive isotope, which they take by mouth. The gland absorbs most of the radiation, and the remainder leaves the body. Special precautions to prevent exposure to people in close contact with patients are necessary for a short time.
High dose rate brachytherapy
- Greater patient comfort
- Shorter recovery time
- Reduced side effects
What is high dose rate brachytherapy?
Traditional X-ray treatments and high dose rate (HDR) brachytherapy are two types of radiation treatment. They are similar in that they both use radiation to treat cancerous growths. However, they differ in the type of radiation used and in the method of administering the radiation to the tumor.
X-ray treatments direct radiation into the tumor from outside the body. A device called a linear accelerator generates X-rays that have enough energy to penetrate and treat cancer deep inside a person's body.
HDR brachytherapy is possible when medical personnel can directly access a tumor and place a catheter in contact with it. The source of radiation is a very small pellet of radioactive material called an isotope. This pellet continually produces radiation as it undergoes radioactive decay. The staff at Thompson Cancer Survival Center at Methodist uses HDR brachytherapy to treat people who have cancer of the lungs, uterus, cervix or vagina.
What should a person undergoing HDR brachytherapy expect?
A team that includes physicians, therapists, a physicist, and a dosimetrist plans each patient's treatment on an individual basis. Patients may generally expect the following:
- Outpatient care: People undergo treatment on an outpatient basis while family or friends wait in the cancer center reception area.
- Medications: Patients with lung cancer receive the same medications they would receive for a bronchoscopy, and they generally require the same recovery time for the sedating effects to diminish. Women with cervical, uterine or vaginal cancer who have had a hysterectomy do not receive any medication prior to the treatment. Women who have not had a hysterectomy receive a mild sedative, which they take by mouth, before treatment.
- Preparation: For lung treatments, a pulmonary physician performs a bronchoscopy to visually localize the tumor in the lung airways. The physician or other medical professional marks the position and places a thin hollow tube applicator, called a catheter, alongside and/or through the visible cancer. After removing the bronchoscope, a radiation therapist takes X-rays to record the applicator's location. Women with cervical, uterine or vaginal cancer who have had a hysterectomy do not have any preparation before treatment. Those who have not had a hysterectomy have a minor surgical procedure before treatment.
- Radiation Dosage: A radiation oncologist prescribes the radiation dose for each treatment, and a physicist and a dosimetrist use computers to determine the details of each treatment and deliver the radiation dose accurately and safely.
- Treatment: After dosage calculations are complete, medical personnel move the patient by stretcher to the treatment room, where the HDR brachytherapy device is attached to the applicator. From outside the room, the treatment team monitors the patient via closed-circuit television with audio contact. As the patient rests quietly, a computer-controlled radioactive pellet moves to the calculated position. After a few minutes, the pellet is withdrawn and placed in a shielded storage unit.
- Recovery: Medical personnel disconnect the device and remove the applicator. The patient remains in a resting position until the sedative medication wears off and then goes home with no special radiation precautions required.
While the actual HDR brachytherapy treatment time is only a few minutes, patients should allow up to four hours for preparation, treatment and recovery. The number and timing of treatments vary according to each patient's situation, but most people typically receive three to five treatments every seven to fourteen days. Some patients receive HDR brachytherapy in addition to chemotherapy, external X-ray radiation, and/or surgery.
Patients interested in receiving an evaluation for HDR brachytherapy should ask their physician to call Thompson Cancer Survival Center at Methodist at (865) 835-4500.
What are the advantages of HDR brachytherapy?
- More radiation to the cancer: Patients receive a higher dose of radiation, which has a greater effect on the cancer.
- Reduced side effects: Patients experience reduced side effects because of less radiation exposure to normal tissue.
- Shorter actual treatment time: HDR brachytherapy takes only a few minutes, although the entire procedure, including preparation and recovery, may take up to four hours. In comparison, the older form of treatment, low dose rate brachytherapy, required a one-to-three day stay in a hospital to accomplish the same results.
- Greater accuracy: The radiation source is a very short distance from the tumor, which increases the precision.
- Shorter recovery time: Patients undergoing HDR brachytherapy in the lung airway, for example, recover in about the same time they would recover from a typical bronchoscopy procedure.
- Less likelihood of pneumonia: HDR brachytherapy often prevents airway obstruction from a tumor growing in the lung airway. This reduces the likelihood that the patient will develop pneumonia.
- Greater patient comfort: Faster treatment means that catheters are removed sooner.
- Increased safety: Unlike low dose brachytherapy, this treatment results in absolutely no radiation exposure to the patient's family.
Radiation oncologists
All of the radiation oncologists on Methodist's medical staff are board certified, which means they have completed several years of additional training in their field after earning their medical degrees.
The radiation oncologists who treat patients at Thompson Cancer Survival Center at Methodist are as follows:
Kenneth Strike, M.D., is board certified in radiation oncology. He graduated from Wake Forest University and completed an internship in surgery and internal medicine at the University of Tennessee Medical Center. He also completed a residency in radiation oncology at the University of Cincinnati. Dr. Strike is a member of the American Society of Therapeutic Oncology and the South Carolina Medical Society.
Lee Carder, M.D., is a graduate of the University of Florida College of Medicine in Gainesville. She also completed a general surgery internship, a radiation oncology residency and a radiation oncology fellowship at the University of Florida. She is board certified in radiation oncology and is a member of the American Society of Therapeutic Radiology and Oncology.
William McDonald, M.D., is a board-certified radiation oncologist on the staff of Methodist Medical Center of Oak Ridge and Thompson Cancer Survival Center in Knoxville. He is a graduate of Emory University School of Medicine in Atlanta and received his specialty training in radiation oncology at the University of Virginia in Charlottesville. Dr. McDonald is a member of the American Society of Therapeutic Radiation Oncology and the American Medical Association.
