Internal Radiation Therapy (Brachytherapy)
Internal radiation therapy, also known as brachytherapy, is a sophisticated form of cancer treatment where radioactive sources are placed inside or near the tumor. This method allows a high dose of radiation to target cancer cells directly while minimizing exposure to surrounding healthy tissues. Brachytherapy is an effective treatment option for various types of cancer and is often chosen for its precision and ability to deliver concentrated radiation doses.
How Internal Radiation Therapy Works
Direct Placement: Radioactive material is positioned in or near the tumor site. This placement can be achieved through various methods depending on the cancer's location and type. For instance, radioactive seeds or wires may be implanted in or near tumors within body cavities or tissues. The placement is typically done using imaging guidance, such as ultrasound, CT scans, or MRI, to ensure accurate positioning.
Targeted Radiation: The proximity of the radioactive source to the tumor enables a high radiation dose to be delivered directly to the cancer cells. This maximizes the treatment's effectiveness and minimizes radiation exposure to healthy tissues. The precise delivery of radiation helps in reducing the risk of damage to nearby organs and tissues, thus preserving their function and reducing side effects.
What to Expect from Brachytherapy Treatment
Types of Internal Radiation Therapy
Permanent Brachytherapy: This type involves placing small radioactive seeds in or near the tumor permanently. The radiation dose gradually decreases to zero as the radioactive material decays over time. The seeds remain in the body but become inactive eventually. Permanent brachytherapy is commonly used for prostate cancer, where the seeds provide a continuous low dose of radiation to the tumor over several months.
Temporary Brachytherapy: This involves placing radioactive material inside the body for a specified period before removal. Temporary brachytherapy can be administered in several sessions (fractions), with the radioactive sources placed for minutes or hours depending on the cancer type and treatment plan. This method is often used for gynecological cancers, such as cervical and uterine cancers.
Common Applications of Internal Radiation Therapy
Prostate Cancer: Radioactive seeds are often implanted directly into the prostate gland. This treatment is highly effective in targeting prostate tumors while sparing surrounding healthy tissues, such as the bladder and rectum.
Cervical Cancer: Radioactive sources are positioned near the cervix to treat cervical cancer. This method is particularly beneficial for locally advanced stages of the disease, where it can shrink tumors and reduce the risk of recurrence.
Breast Cancer: Brachytherapy may be used post-lumpectomy to target the area where the tumor was removed. This approach helps in minimizing the risk of cancer recurrence in the treated breast.
Skin Cancer: Radioactive sources can be placed on the skin's surface to treat certain types of skin cancer. Brachytherapy for skin cancer is often used when surgical options are limited or when cosmetic outcomes are a priority.
Considerations and Potential Side Effects
Local Irritation: Common side effects include irritation at the implant site, swelling, and discomfort. These side effects are usually temporary and manageable with appropriate care.
Risk of Radiation Exposure: Although generally safe, there is a small risk of radiation exposure to family members, necessitating specific precautions for temporary brachytherapy patients. Patients may need to follow certain guidelines to minimize radiation exposure to others during the treatment period.
Infection Risk: As with any procedure involving implants, there is a risk of infection. Patients are monitored closely for signs of infection, and antibiotics may be prescribed as a preventive measure.
Advantages of Internal Radiation Therapy
Precision: Brachytherapy delivers high radiation doses directly to the tumor with minimal impact on healthy tissues. This precision reduces the risk of side effects and damage to surrounding organs.
Effectiveness: The concentrated radiation can be more effective than external beam radiation in certain cases. Brachytherapy's ability to deliver a high dose to the tumor in a shorter time frame enhances its therapeutic impact.
Convenience: Treatment durations are typically shorter, and permanent brachytherapy can reduce hospital stays. Patients undergoing temporary brachytherapy often require fewer treatment sessions compared to external beam radiation therapy.
