Brachytherapy

Overview

Brachytherapy, also known as internal radiation, is a cancer treatment that involves placing radioactive material directly inside the body. This method allows for higher, more concentrated doses of radiation to be delivered to the tumor, minimizing exposure to surrounding healthy tissues. A significant advantage of brachytherapy is the potential for shorter overall treatment times due to the ability to administer larger doses safely in fewer sessions.

What Is Brachytherapy?

Brachytherapy is a form of radiation therapy where a sealed radioactive source is temporarily or permanently placed inside or next to the area requiring treatment, such as a tumor. This internal placement allows for a highly targeted and potent dose of radiation to be delivered precisely to the cancerous cells, while sparing nearby healthy organs and tissues from unnecessary radiation exposure.

Types of Brachytherapy

Brachytherapy treatments come in various forms differing in radiation strength (dosage) and treatment duration. It is crucial to follow the instructions provided by your radiation oncologist regarding safe interactions with others if you are undergoing internal radiation.

There are three main types of brachytherapy implants:

• Low-dose rate (LDR)

LDR implants continuously emit low doses of radiation for a period ranging from one to seven days. Due to the potential risk of exposing others to radiation during this time, patients typically stay in the hospital for the duration of treatment. There may also be restrictions on visitors, particularly for vulnerable populations such as children or pregnant individuals.

• High-dose rate (HDR)

HDR implants release high doses of radiation over a short period, usually 10 to 20 minutes. Treatment schedules can vary, with some patients requiring sessions twice a day for up to five days, while others may have treatment once a week for up to five weeks. Many individuals receiving HDR treatment go to the hospital for the procedure, leave on the same day, and return for subsequent treatments if necessary. During the treatment sessions, there is a potential risk of exposing others to harmful radiation. To mitigate this risk, your medical team may observe you from a nearby room or wear protective gear during interactions. Once the treatment sessions are completed, there is no longer a risk of radiation exposure to others.

• Permanent

Permanent radioactive implants, often referred to as seed implantation, continuously release radiation, with the level of radioactivity decreasing rapidly over time until they become inactive. These tiny implants, about the size of a grain of rice, remain in your body. Initially, your healthcare provider may limit your interactions due to radiation emission. However, as time passes, you should be able to interact with others safely without exposing them to radiation.

Advantages of Brachytherapy

Brachytherapy is most effective for cancer cases in which metastasis, the spread of cancer throughout the body, has not spread. It is particularly well-suited for treating localized tumors, those confined to a specific area of the body, as this internal radiation can successfully eradicate them.

Brachytherapy is used to treat different kinds of cancer. These include the following:

• Brain cancer.
• Breast cancer.
• Cervical cancer.
• Endometrial cancer.
• Esophageal cancer.
• Eye cancer.
• Gallbladder cancer.
• Head and neck cancers.
• Lung cancer.
• Prostate cancer.
• Rectal cancer.
• Skin cancer.
• Soft tissue sarcomas.
• Thyroid cancer.
• Uterine cancer.
• Vaginal cancer.

Brachytherapy Procedure

Undergoing brachytherapy involves a series of steps, from initial preparation to the actual procedure and post-treatment care. 

Before the procedure

The healthcare provider will advise the patient on how to prepare. 

• Healthcare provider will conduct a physical examination.
• Current medications, historical medical conditions, and previous surgical procedures must be disclosed to the healthcare provider.
• If the patient is breastfeeding or pregnant, they will need to inform the healthcare provider.
• Healthcare providers will recommend having an imaging test, such as a computed tomography (CT) or magnetic resonance imaging (MRI).
• Stop using medications that change blood clotting, such as blood thinners (anticoagulants) or nonsteroidal anti-inflammatory drugs (NSAIDs).
• Before the procedure, the patient will undergo an enema for bowel preparation.
• Patients will avoid eating or drinking for several hours before the procedure.
• Patients are advised to stop smoking or using tobacco products.

During the procedure

The procedure depends on the type of cancer, the location of the implants, and the type of brachytherapy (HDR, LDR, or permanent):

• Intracavity brachytherapy:  Implants are positioned inside a bodily cavity, such as the vagina, close to the tumor.
• Interstitial brachytherapy: The tumor is directly penetrated by the implants.

The patient will be given medication to keep them comfortable throughout the entire process. A sedative and anesthetic may be administered to the patient in order to alleviate their pain. Once they are comfortable, their healthcare provider will:

• Place an applicator device, such as a catheter, which is a small flexible tube, into the tumor in order to deliver radioactive implants. Correct placement can be ensured with the assistance of imaging (MRI, ultrasound, or X-ray).
• Insert the implant into the catheter or applicator device and continue until it reaches the tumor. The duration of the implant will depend on the type of brachytherapy. HDR involves the implant being removed by the healthcare provider following treatment sessions.
• The implant can be taken out at the end of every treatment and put back in at a later time, or the healthcare provider can leave it in place the entire while the patient is receiving LDR type.

The patient will be given medications to help with any discomfort that might occur after the catheter or applicator device is removed.

After the procedure

Following treatment, the patient might need to restrict their activities and receive more rest. Patients should follow the instructions provided by the healthcare provider to ensure it is safe to resume the regular activities.

Patients undergoing persistent internal radiation should diligently adhere to their healthcare provider’s guidance regarding safe social interactions. In cases where brachytherapy may potentially expose others to radiation over a period of several weeks or months, it is essential to follow these recommendations. Even if the risk of exposure is minimal, the healthcare provider’s advice should be heeded, especially with regard to limiting interactions with young children and expectant mothers.

Risks and Side Effects of Brachytherapy

Brachytherapy has potential negative effects, just like any other cancer treatment. Once therapy is stopped, the majority of adverse effects go away, but some are long-lasting or don’t show up right away. 

Side effects depend on the part of the body being treated. For example, treatment in the pelvic area may affect urinary or bowel functions, while treatment for head and neck cancer may cause mouth sores. A few months after treatment ends, adverse indicators usually get better.

The following risk includes:

• Fatigue.
• Hair loss.
• Headaches.
• Mouth sores.
• Nausea and vomiting.
• Constipation or diarrhea.
• Cough or shortness of breath.
• Difficulty to urinate or urinary incontinence.
• Erectile dysfunction.

Brachytherapy Treatment Results

Brachytherapy is an effective treatment option for certain cancer types, particularly those that have not metastasized or spread to other areas of the body. As the radiation exits the body, most of the adverse side effects tend to improve.

If the patient experiences any of the following symptoms when receiving treatment, they should contact their healthcare provider:

• Difficulty in breathing
• Problem in swallowing.
• Nausea and vomiting
• Diarrhea.
• Urinary incontinence.
• Fecal incontinence.