Brachytherapy is a procedure that involves
The radioactive 'seeds' being placed.
Radiation therapy uses high-powered energy beams, such as X-rays, to kill cancer cells. Radiation therapy can be directed at your lung cancer from outside your body (external beam radiation) or it can be put inside needles, seeds or catheters and placed inside your body near the cancer (brachytherapy).
Radiation therapy can be used alone or with other lung cancer treatments. Sometimes it's administered at the same time as chemotherapy.
For people with lung cancers that are very small, one option may be stereotactic body radiotherapy (SBRT). This form of radiation aims many beams of radiation from different angles at the lung cancer. Stereotactic body radiotherapy treatment is typically completed in one or a few treatments. In certain cases, it may be used in place of surgery for small tumors.