What should you know about your first linear accelerator treatment?

A linear accelerator, often called a linac, creates high-energy radiation for cancer treatment. Before the first session, the team uses scans and planning measurements to shape the beam and set the treatment position. Small marks or a positioning device may help you return to the same alignment each time.

During treatment, you lie on a firm table while the machine moves around you without touching you. The radiographers leave the room but watch and communicate with you. You do not feel the radiation itself, although the position, equipment, and need to remain still can feel unfamiliar.

Wear comfortable clothing and follow any instructions about eating, drinking, medicines, or bladder preparation. Tell the team if lying flat is difficult, if you feel anxious in enclosed spaces, or if you have an implanted medical device. Avoid rubbing treatment marks and ask before applying products to the treatment skin.

After treatment, most people can leave as planned, but the schedule depends on the treatment course. Skin changes, tiredness, or other effects depend on the body area and dose pattern; the team will explain which changes to watch for.

Contact your radiation team for worsening pain, marked skin reaction, trouble swallowing, persistent vomiting, new weakness, or symptoms that prevent eating, drinking, or normal breathing. Seek urgent care for severe breathlessness, sudden confusion, or collapse.

What preparation is needed for my treatment area? How will you keep my position consistent? How many visits are planned, what side effects fit this body area, and who should I call outside the treatment appointment?