Targeting Cancer with Precision: A Guide to Brachytherapy

One of the first things many patients say when they hear the word "brachytherapy" is, "What exactly is that?"

It's a treatment most people have never heard of until they need it, so it's completely understandable if it feels unfamiliar or intimidating at first. One of the goals of this guide is simply to take some of the mystery out of the process so you know what to expect before, during, and after treatment.

What Is Brachytherapy?

Brachytherapy is a specialized form of radiation therapy in which a radioactive source is placed inside—or very close to—the area being treated.

Unlike external beam radiation therapy, which delivers radiation from outside the body, brachytherapy delivers radiation directly where it's needed. Because of that precision, very high doses of radiation can be delivered to the cancer while limiting exposure to nearby healthy tissues.

For many gynecologic cancers, brachytherapy is an important component of treatment and is often combined with external beam radiation therapy to achieve the best possible treatment outcomes.

There are two main approaches.

Intracavitary Brachytherapy

In intracavitary brachytherapy, a specialized applicator is placed inside a natural body cavity, such as the vagina or uterus.

Radiation is then delivered directly through that applicator, allowing treatment to concentrate on the cancer while minimizing radiation exposure to nearby organs such as the bladder and rectum.

This is the most common type used for cervical and many uterine cancers.

Interstitial Brachytherapy

Sometimes the tumor's size or location requires an even more customized approach.

With interstitial brachytherapy, thin needles or catheters are placed directly into or around the tumor so radiation can be delivered with even greater precision.

This approach is commonly used for certain cervical, vaginal, and vulvar cancers.

One of brachytherapy's greatest advantages is its precision. By placing the radiation source directly where treatment is needed, your team can deliver an effective dose while minimizing radiation exposure to nearby healthy tissues.

What to Expect During the Procedure

Every brachytherapy procedure is a little different depending on the type of cancer being treated and the technique being used. Regardless of the approach, your team's priority is making the procedure as comfortable as possible.

What to Expect After the Procedure

Although everyone's experience is different, many people find that recovery is easier than they expected. Exactly what you experience depends on the type of brachytherapy you receive.

Some pelvic soreness or cramping for a day or two after treatment is common and often feels similar to menstrual cramps. Many people find that over-the-counter pain medication is sufficient, while others may receive additional recommendations from their care team.

Light spotting or discharge: A small amount is common and usually resolves within several days.

Fatigue: If brachytherapy is part of a longer course of radiation treatment, it's common to feel more tired than usual. Give yourself permission to rest when you need to.

Vaginal changes: Some women notice vaginal dryness, increased sensitivity, or tightening over the weeks and months after treatment. Bring these changes up early. Depending on the type of brachytherapy you receive, your radiation oncologist may recommend vaginal dilator therapy after treatment and will explain when it's safe to begin. Your physician will also let you know when it's appropriate to resume sexual activity. For more detail, see 'Vaginal Health After Pelvic Radiation.'

Recommended During Recovery

Designed for intact external vulvar, perineal, and perianal skin during and after pelvic radiation treatment, including brachytherapy. For external use only. Not intended for internal vaginal use.

You're Not Facing This Alone

It's completely normal to feel anxious before a procedure you've never experienced before.

Remember that brachytherapy is a treatment your radiation oncology team performs regularly. They'll guide you through each step, answer your questions, and make adjustments whenever possible to keep you comfortable.

Ask every question you have. Tell your team what's worrying you. If something doesn't feel right before, during, or after treatment, let them know.

You don't have to understand every technical detail of brachytherapy before treatment begins. But understanding the basics—and knowing what to expect—can make the experience feel much less overwhelming.