Brachytherapy for Cervical Cancer

Brachytherapy is a type of radiation therapy that is sometimes used to treat cervical cancer. Also known as internal radiation therapy, it involves the placement of a radioactive material inside or near a tumor. Due to its precise placement, the radiation must travel only a short distance to reach its target. In addition to minimizing any effects on the surrounding healthy tissues, such as the bladder and bowel, brachytherapy allows for a larger dose of radiation to be safely delivered at one time.

When radiation therapy is used as a primary treatment for cervical cancer, brachytherapy is usually administered in addition to external beam radiation therapy (EBRT). However, it may also be used as a standalone treatment for certain early-stage cervical tumors.

Types of brachytherapy

There are two main types of brachytherapy:

• Low-dose rate (LDR) brachytherapy - The patient is hospitalized and remains in bed while a low-dose treatment is delivered in a single, multi-day session. During treatment, special medical instruments are used to hold the radiation source in place.
• High-dose rate (HDR) brachytherapy - A high-dose treatment is delivered during several outpatient sessions scheduled at least one week apart. During each session, the radioactive material is inserted for a few minutes and then removed.

Where is the radiation source placed?

The type of brachytherapy most frequently used to treat cervical cancer is intracavitary brachytherapy. If the patient has had a hysterectomy, the radioactive material may be placed in a tube (applicator) in her vagina.

If the patient’s uterus is intact, the radioactive material may be placed in a two-part applicator. The first part is a small, thin metal tube (tandem), which will be passed through her cervix and into her uterus. The second part consists of several small circular capsules (ovoids) or a hollow metal ring, which will be placed in her vagina against her cervix. This type of brachytherapy is known as tandem and ovoid (T&O) or tandem and ring (T&R) treatment.

The brachytherapy applicator for T&O or T&R treatment will be placed during a surgical procedure. Afterward, imaging scans will be performed to confirm proper placement.

How is brachytherapy delivered?

Once proper applicator placement is confirmed, the patient will be taken to a lead-lined room to receive brachytherapy. The applicator will be connected to an external machine, which will automatically feed a radiation source into it. The radioactive material will remain in place for up to 25 minutes (dwell time) depending on the patient’s treatment plan. Once the dwell time is up, the machine will remove the radiation source from the applicator.

If the patient is receiving LDR brachytherapy over a few days, the applicator will remain in place—and the patient will remain hospitalized and in bed—until the treatment is completed. If the patient is receiving HDR brachytherapy in weekly sessions, the applicator will be removed after each session.

What are the possible side effects of brachytherapy?

Because the radiation travels only a short distance with brachytherapy, the side effects usually affect the cervix and vaginal walls. The most common side effect is vaginal irritation, which can cause the vagina to become red and tender. The vulva may become irritated as well. Some patients also experience vaginal bleeding or discharge and cramps. 

Additionally, brachytherapy can cause many of the same side effects as EBRT, such as:

• Weakness and fatigue
• Nausea
• Diarrhea
• Bladder irritation
• Low blood cell counts 

Benefit from world-class care at Moffitt Cancer Center

If you have questions about brachytherapy for cervical cancer, you can request an appointment with a specialist in the gynecological clinic at Moffitt by calling 1-888-663-3488 or submitting a new patient registration form online. We do not require referrals.