In 1989 the University of Wisconsin implemented a unique method of internal radiation called high dose rate (HDR) brachytherapy. Brachytherapy refers to radiation that is given from a short distance, in contrast to external beam radiation, or teletherapy, which is given from a longer distance. In the majority of these treatments radiation applicators are placed within a cavity of the body such as the bronchus (airway) in the lung, esophagus, vagina, cervix or uterus. The primary advantage of internal radiation is the ability to deliver a higher radiation dose while the normal tissues receive less radiation since the radiation sources are placed within the tumor.
Brachytherapy has been used to cure cervical cancer since the beginning of the century. This successful treatment for gynecologic malignancies was developed in Europe by a number of institutions. Both radium and cesium have been used as radioactive sources to give the internal radiation. Low dose rate (LDR) brachytherapy was implemented as the first internal radiation system. Low dose rate brachytherapy refers to radiation that is delivered slowly, or at a low dose rate. In order to prescribe a radiation dose that will eliminate the cancer, the instruments need to be in place for an extended period of time. Therefore, patients stay in the hospital with applicators in the gynecologic tract for 2 to 3 days. For cervical cancer patients, the procedure is repeated one week later.
While low dose rate brachytherapy had been successfully used for decades in the treatment of gynecololgic malignancies, there are disadvantages which include radiation exposure to hospital staff, potential movement of the placid instruments since the treatment time takes 2-3 days, costs incurred from hospitalization, patient discomfort and inconvenience. In the late 1960's many institutions in Europe and Japan began to develop high dose rate systems to overcome the above disadvantages of low dose rate brachytherapy.
High dose rate brachytherapy refers to radiation that is given very rapidly. In contrast to low dose rate brachytherapy where treatments require 2 to 3 days, HDR brachytherapy is delivered over minutes. In order to prevent potential complications from HDR brachytherapy, multiple insertions are required. For cervical cancer patients, 5 insertions has become the standard of care. Although 5 insertions in HDR brachytherapy may appear to be less convenient than 2 LDR insertions, the total time that applicators are in the gynecologic tract (vagina, cervix and/or uterus) for each insertions is on average 2 1/2 hours for the HDR approach in contrast to 50 hours for the LDR approach. For endometrial cancer patients that are receiving brachytherapy alone or in combination with external beam radiation after a hysterectomy, a total of 2 insertions are used in which each insertion lasts about 1 hour.
The University of Wisconsin has one of the largest HDR brachytherapy programs in the United States. We routinely perform over 400 insertions per year. The rationale, methodology and results of our system have been extensivley published in peer reviewed scientific journals. We have now treated over 200 patients with HDR brachytherapy alone after a hysterectomy with no patients suffering a recurrence of their tumor at the top of the vagina, nor has any patient experienced a significant complication. For endometrial cancer patients requiring both external and internal radiation, our results in approximately 60 patients have also been excellent in regards to cure and complications. About 200 cervical cancer patients have been treated with HDR brachytherapy. Compared to the previous LDR approach, the results are comparable. At this point the scientific literature indicates that LDR and HDR brachytherapy are comparable in regards to both cure and complication rates.
The advantages of HDR brachytherapy include outpatient treatment, patient convenience, economic savings, precise radiation delivery since there is essentially no applicator movement with the short treatment times, and the ability to tailor the radiation doses since multiple treatments are ultilized. It is important to recognize that the experience of the physician/institution performing the brachytherapy is more critical than the type of brachytherapy delivered.
Contents |
Details of the Procedure for Patients Undergoing HDR Brachytherapy
The internal radiation treatments are delivered in a dedicated surgical suite in the department of radiation oncology. Cervical cancer patients have 5 treatments once to twice per week, in conjunction with external beam radiotherapy the remaining days of the week. The total time in the brachytherapy suite is about 2.5 hours for patients with cervical cancer and 1 hour for patients with endometrial cancer. For patients with endometrial cancer who have had a hysterectomy 2 insertions are usually given. Intravenous medications are given to make you sleepy and comfortable. The amount of sedation required is less for endometrial patients since the total time in the brachytherapy suite is markedly shorter.
What do the applicators look like?
The applicators that are inserted into the vagina or uterus vary in size and shape to match different body types. Your doctor will chose the one that fits you best. Below are examples of the applicators used and where they are placed.
| First header | Second header | ||||
|---|---|---|---|---|---|
| upper left |
right side | ||||
| lower left | lower middle | ||||
| |||||
Applicators used in HDR brachytherapy. Tandem and cylinders used for cervical cancer.
Tandem and ovoids used for cervical cancer. Sideview of the instruments placed in a patient with cervical cancer.
View from within the vagina in a patient with cervical cancer. Ovoids used in patients with endometrial cancer after a hysterectomy.
Instructions for applicator placement for cervical cancer
Patients need to check in at the radiotherapy front desk and then have a seat in the main waiting room. Since the medications given for the procedure will make you sleepy, you will need to have someone bring you to the department and take you home. This person(s) can wait in the main waiting room during the treatment.
Do not eat or drink liquids 4 hours before the procedure. If you take prescription medications in the morning, you may do so with a sip of water. If you are diabetic, please discuss your medication requirements with your doctor or nurse prior to the procedure.
Prior to the procedure you will be asked to change into a gown. A small needle will be placed in your hand or arm to give you m edications. Your nurse will monitor your vital signs, give medications, and provide nursing care. Please let your nurse know if there is anything you need, or if you have any concerns.
It has been our experience that a small proportion of patients undergoing this procedure require a different type of sedation or anesthesia. Many of these patients have had a history of physical, emotional, and/or sexual trauma. If you have a history of any one of these traumas, or think that you may require more sedation, please discuss with your doctor or nurse. We do have resources to help you. By informing us ahead of time, you can prevent a delay in your treatment. It is very important that we complete your radiation in a timely fashion with minimal treatment interruptions.
Procedural Details
Exam and placement of the applicator
During the procedure you will lie on your back with your legs elevated in stirrups. You will remain in this position until the treatment is completed. Medications will be given to make you comfortable and they can make you feel drowsy. The doctors will do a pelvic exam to determine which size and shape of applicator to use.
The perineum is prepped with betadine (anti-bacterial soap). A foley catheter (small tube) will be placed into the bladder to drain any urine before the procedure. It will be removed when the treatment is completed.
A small metal seed is inserted into either the top of the vagina or cervix that assists in radiation treatment planning. One seed is placed during each insertion. This metal seed in not radioactive, but may someday work itself out of the tissues where you may notice it.
The proper applicator is then placed inside your vagina and/or uterus. This can cause some cramping (similar to menstrual cramps) and pressure. If this is uncomfortable, more medication will be given if you need it. Wet gauze is then packed inside the vagina to hold the applicator in place. This may cause some temporary pressure inside the vagina. The amount of discomfort associated with the procedure is similar to a pelvic exam.
A small flexible catheter will then be inserted into the rectum where a small amount of dilute barium (white substance) will be administered with subsequent removal of the cather.
This part of the procedure takes about 20-25 minutes.
X-Rays
X-rays will be taken to assure proper placement of the applicator. This part of the procedure takes about 15 minutes.
Computer Calculations
Calculating the dose of radiation for your treatment is very complex, so a computer must be used. Computer calculations take place to determine the amount of time needed to deliver the correct dose of radiation to the tumor site.
This part of the procedure takes about 45-60 minutes. You may still be a little sleepy during this time.
The Radiation Treatment
Before the treatment starts, cables from the treatment machine will be attached to the applicator. During the treatment the radioactive source will slide inside the applicator and stay there for the proper amount of time (about 5-15 minutes) determined during the computer planning. During this time, most patients are awake. You will not feel the treatment as it is given. You will hear a clicking or humming of the treatment machine. You will be alone in the room during the treatment but we will be able to see and hear you on a monitor. We can also talk to you through a speaker. After the treatment is completed, the applicator and foley catheter will be removed.
You will be able to go home after the treatment is completed. Your memory of the procedure may be "fuzzy." This is a short term side-effect of the medications. Since medication is given during the procedure, we advise that you avoid driving and abstain from alcohol for at least 12 hours.
What You Might Expect After the Procedure
Spotting and bleeding from your vagina is expected. It should not be more than a normal menstrual period. You may bring a sanitary pad from home or we will give you one to wear. We recommend that you not use tampons. Avoid douching during the course of treatment. Douching can disrupt the body's natural chemical balance. You may experience some vaginal or abdominal cramping (similar to menstrual cramps) after the procedure. This should stop by the end of the day. Ibuprofen (Advil, Motrin, or Nuprin) or naproxen (Naprosyn, or Aleve) may be helpful. Take it according to the directions on the bottle. A foley catheter was placed into your bladder during the procedure. You may have some irritation or burning when you first urinate after the procedure. You should drink 8-12 glasses of fluids each day for the next 1-2 days. A small amount of barium was inserted into your rectum. Your next bowel movement may look white or gray in color. You will be given a vaginal dilator to use if you do not already have one. The radiation causes the vagina to narrow and tighten. There will be an explanation and instructions given to you. It is safe to have sexual intercourse between treatments. Your memory of the procedure may be "fuzzy." This is a short term side-effect of the medications. After your treatment, you may resume your normal diet. You are not radioactive after the procedure. Notify Dr. Bradley or his resident at 608-263-8500 for any of the following symptoms: Fever above 101°F. Pain that is not relieved with medication. Bleeding more than a normal menstrual period. Burning with urination or blood in the urine lasting more than 24 hours.