The XRT medical abbreviation means radiation therapy, a treatment that uses carefully aimed high energy rays to damage cancer cells so they stop growing. The X comes from X-ray therapy, the older name, and the RT stands for radiation therapy. You may also see it written as RT, RTx or radiotherapy.
The term appears in oncology notes, tumor board summaries and treatment plans, often with a dose in units called gray (Gy) and a number of sessions called fractions. It is a treatment, not a picture, which sets it apart from look-alike imaging shorthand such as XR for an X-ray. The sections below decode a typical plan and the words that travel with it.
At a glance
Stands for
Radiation therapy (from X-ray therapy)Also written
RT, RTx, radiotherapy, EBRT for external beamSpecialty
Radiation oncologyDose units
Gray (Gy); older notes may use centigray (cGy)Do not confuse with
XR (X-ray imaging) and Rx (prescription)Where you see it
Oncology notes, cancer treatment plans, problem lists, discharge summaries
What the XRT medical abbreviation covers
Radiation therapy damages the genetic material inside cells. Cancer cells are generally less able to repair that damage than healthy cells, so over a course of treatment the tumor shrinks or is destroyed while nearby normal tissue has time to recover. The treatment is planned with scans so that the beams focus on the target and limit the dose to surrounding organs.
XRT can be the main treatment, can follow surgery to lower the chance of cancer returning, can come before surgery to shrink a tumor, or can ease symptoms such as bone pain. It is often combined with chemotherapy, a pairing called chemoradiation.
Decoding a radiation therapy plan
A radiation plan has its own vocabulary. This sample line shows the usual parts.
| Part | Meaning |
|---|---|
| Adjuvant | Given after surgery to lower the risk of return |
| XRT | Radiation therapy |
| to left breast | The area being treated |
| 40 Gy | The total planned dose in gray |
| in 15 fractions | Split into 15 daily treatment sessions |
Oncology summary: "Completed concurrent chemo and XRT, tolerated well, mild skin redness." This means chemotherapy and radiation were given during the same weeks, and the main side effect was skin irritation in the treated area.
Types of radiation you may see named
External beam radiation, written EBRT, comes from a machine outside the body and is the most common form. Treatments are usually given on weekdays over several weeks, and each session takes only minutes of actual beam time. Brachytherapy places a radiation source inside or right next to the tumor. SBRT, stereotactic body radiation therapy, gives a few very precise, high dose treatments to small tumors. IMRT, intensity modulated radiation therapy, shapes the beam closely to the target. Notes may simply say XRT and leave the technique to the radiation oncology record.
XRT versus XR, Rx and other look-alikes
| Abbreviation | Meaning | Treatment or test? |
|---|---|---|
| XRT | Radiation therapy | Treatment |
| XR | X-ray image | Test |
| CXR | Chest X-ray | Test |
| Rx | Prescription or treatment in general | Order |
| RT | Radiation therapy, or respiratory therapy in other settings | Depends on context |
An imaging X-ray uses a tiny dose to make a picture, while radiation therapy uses much larger, focused doses to treat disease.
Side effects and what the chart follows
Side effects depend on the area treated. Skin redness and tiredness are common, while treatment near the throat, belly or pelvis can cause other effects specific to those organs. Weekly on-treatment visits record how the person is doing, and later notes track results through scans and exams.
This explains the abbreviation in general terms. Specifics of any treatment course and its likely side effects come from the radiation oncology team.
Other procedure terms are collected on the surgery and procedures page.
Frequently asked questions
What does XRT mean in cancer treatment?
XRT means radiation therapy, treatment with focused high energy beams to damage cancer cells. It may be used alone or with surgery and chemotherapy.
Why is radiation therapy abbreviated XRT?
The X comes from X-ray therapy, an older name for the treatment, and RT stands for radiation therapy. Many notes now simply write RT.
What does Gy mean in a radiation plan?
Gy stands for gray, the unit that measures the radiation dose absorbed by tissue. The plan lists a total dose and how many sessions it is split into.
Is XRT the same as an X-ray?
No. An X-ray, often written XR, is a quick imaging test with a small dose. XRT is a course of treatment that uses much higher, carefully aimed doses.
Does radiation therapy make a person radioactive?
External beam XRT does not leave the person radioactive. Some internal treatments do for a period, and the team gives specific instructions when that applies.