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How are radioactive seeds used to treat prostate cancer?

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linear accelerator; external beam radiation therapy — radiation therapy External beam radiation therapy (also known as external beam teletherapy, or long-distance therapy) being delivered using a machine known as a linear accelerator.

The use of radioactive seeds to treat prostate cancer is a form of radiation therapy known as brachytherapy.12

In this procedure, encapsulated radioactive sources—often referred to as seeds—are implanted directly into the prostate tissue. These sources are typically inserted using needles, which allow the radiation to be placed precisely within or in close proximity to the tumor.12

The primary clinical advantage of this technique is its ability to deliver a high, concentrated dose of radiation directly to the cancerous tissue while sparing the surrounding healthy organs and structures from unnecessary exposure. By localizing the radiation source, brachytherapy minimizes the impact on the rest of the body compared to external beam radiation.1