Brachytherapy is a form of radiation therapy in which radioactive sources are placed directly into or near a tumor. This allows for a targeted dose of radiation to be delivered to the tumor while minimizing the exposure of surrounding healthy tissue. Brachytherapy is commonly used to treat various types of cancer, including prostate, breast, and cervical cancer. It can be used as a standalone treatment or in combination with other therapies, such as surgery or external beam radiation. Brachytherapy is a minimally invasive procedure that is typically well-tolerated and has fewer side effects compared to other forms of radiation therapy.