Which statement describes how brachytherapy delivers radiation?

Which statement describes how brachytherapy delivers radiation?

• A. Radiation is delivered by implanted radioactive materials directly into the tumor
• B. Radiation is delivered by external beams from outside the body
• C. Radiation comes from radioactive tablets taken by mouth
• D. Radiation therapy uses only ultrasound guidance

Answer: (A)

Brachytherapy delivers radiation from sources placed directly into or near the tumor, either temporarily or permanently. This internal placement allows a high dose to the tumor while sparing surrounding healthy tissue because the radiation dose falls off quickly with distance. The statement describes implanting radioactive materials directly into the tumor, which is the hallmark of brachytherapy. In contrast, external-beam radiation uses beams from outside the body, radioactive tablets taken by mouth deliver systemic radiation rather than targeted internal sources, and ultrasound guidance is just an imaging aid not the method of delivering the radiation itself.

Brachytherapy delivers radiation from sources placed directly into or near the tumor, either temporarily or permanently. This internal placement allows a high dose to the tumor while sparing surrounding healthy tissue because the radiation dose falls off quickly with distance. The statement describes implanting radioactive materials directly into the tumor, which is the hallmark of brachytherapy. In contrast, external-beam radiation uses beams from outside the body, radioactive tablets taken by mouth deliver systemic radiation rather than targeted internal sources, and ultrasound guidance is just an imaging aid not the method of delivering the radiation itself.