Tattoos for Breast Radiation Therapy

These markings are done to help guide treatment

Radiation can be an important part of treatment for breast cancer. During radiation treatment, high-energy beams are aimed at the breast tissue to kill cancer cells.

Before breast radiation is delivered, skin markings known as radiation tattoos, need to be placed on the skin. These marks help the radiation therapist aim the radiation precisely where it's needed.

Radiation is typically given five days a week for about six weeks, and it's critical the radiation is aimed at the same place in order to prevent cancer recurrence and to spare healthy tissue.

This article will review the process of tattoo placement and the types of breast tattoos available, as well as alternatives.

radiation tattoo
Verywell / Jessica Olah

Size and Appearance

Breast radiation tattoos are tiny—about the size of a freckle, or 1 millimeter in diameter. There will often be four tattooed dots, each marking one corner of the area to be irradiated, but some radiation centers may need fewer.

Radiation tattoos are blue or black in color, created by using a drop of ink and a very slender needle. These tattoos won't wash off, so showering or swimming during treatment won't affect them.


Although each radiation treatment center may have some differences, the process of placing radiation tattoos is likely to be similar at most locations.

The first step after radiation has been prescribed is a simulation process. During simulation, a CT scan of the area getting radiation is done. This helps the radiation specialists make a map of where exactly the radiation beams need to go.

During the CT simulation, tattoos are placed, which help mark the treatment field. These need to be placed so the treatment can be accurate each time. When the location of the tattoo is determined, the skin is marked using a marker.

Then the skin is cleaned well, and a drop of ink is placed on the marked skin. A small needle is then used to poke a small hole in the top layer of the skin. This small hole allows the ink to get under the skin. Once under the skin, it cannot be washed off.

The stick of the needle may be slightly uncomfortable, but shouldn't hurt severely.


Many radiation treatment centers use a dark ink for the tattoo, often India ink. The use of dark ink can make it easy for the radiation technologist to properly line up the radiation treatment. However, although the spots are small, they are still visible on the skin. For some people with breast cancer, seeing these spots after treatment can be a constant reminder of their cancer and can cause distress.

Another option is UV (ultraviolet) ink. This type of ink is lighter in color, and also contains a fluorescent dye that can be seen under UV light. When the skin is seen under normal lighting, the tattoo is not visible.

The age and weight of the patient can factor into tattoo marking for radiation. The tattoo placement can be more difficult to set up and may not be as accurate when patients have loose or aging skin.

Side Effects

There are very few side effects related to the use of tattoos for breast cancer radiotherapy. In extremely rare cases, people have had allergic reactions to the dye.


In addition to the traditional dark ink tattoo or the newer UV dye, some radiation centers have used henna to temporarily mark the skin of someone getting radiation. Henna is not permanent, but it may only last up to two weeks. It may require frequent touch-ups to continue to be accurate in marking the skin for radiation.

Henna application can also be a lengthy procedure, with the dye needing to sit on the skin untouched for over an hour to be sure it is on properly.

Some radiation centers can use surface guided radiation therapy (SGRT). During this type of treatment, using a specialized radiation machine, multiple cameras and sensors are used to determine the patient's position without the use of tattoos.

Removal Options

If chances of cancer recurrence are very low and the oncologist agrees, radiation tattoos may be removed.  Options include surgery, dermabrasion, and cryotherapy. A dermatologist should be able to provide guidance on the best method to use.


Tattoos and skin markings are a very important process of using radiation to treat breast cancer. The tattoos help ensure that the radiation beams are being directed in the correct location for the best possible outcome. Most tattoos use a dark ink, but newer options such as UV dye may be a possibility. Henna can be used but needs frequent touch-ups.

After treatment, removal of the tattoos may be possible after discussion with the radiation oncologist.

A Word From Verywell

Coping with radiation tattoos is easier if you understand their purpose and importance. Some women see their radiation tattoos as marks of survival and strength, rather than something they want to have removed. If you wish to have your tattoos removed after treatment, talk with your oncologist.

Frequently Asked Questions

  • Do you have to get tattoos for radiation?

    The skin must be marked before radiation is given, as it ensures that the radiation beams to treat the cancer are applied in the correct spot. Ink tattoos are most frequently used, as they don't come off once they are placed. For some who refuse tattoos, temporary marking such as with a pen or henna ink may be used.

  • Who tattoos you for radiation therapy?

    The highly trained radiation therapists and/or the radiation oncologist are present for the simulation procedure. This procedure is when the tattoos are placed and will be done by one of these professionals.

  • What do radiation tattoos look like?

    Radiation tattoos are usually blue or black in color and are very small. They may look like a freckle.

  • Do radiation tattoos fade?

    Radiation tattoos may fade a bit over time but are usually permanent. Temporary inks, such as henna, will fade quickly, within about two weeks.

7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American Cancer Society. Getting external beam radiation therapy.

  2. Freislederer P, Kügele M, Öllers M, et al. Recent advances in surface guided radiation therapyRadiation Oncology. 2020;15(1):187. doi:10.1186/s13014-020-01629-w

  3. OncoLink. Pictoral overview of the radiation therapy treatment process.

  4. Rathod S, Munshi A, Agarwal J. Skin markings methods and guidelines: A reality in image guidance radiotherapy eraSouth Asian J Cancer. 2012;1(1):27-29.

  5. Rathod S, Munshi A, Agarwal J. Skin markings methods and guidelines: A reality in image guidance radiotherapy era. South Asian J Cancer. 2012;1(1):27-29. doi:10.4103/2278-330X.96502

  6. Kim JJ. Temporary henna tattoos as an alternative marking method for external beam radiation therapy patients who decline permanent tattoosJournal of Medical Imaging and Radiation Sciences. 2015;46(1):S10-S11. doi:10.1016/j.jmir.2015.01.035

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By Julie Scott, MSN, ANP-BC, AOCNP
Julie is an Adult Nurse Practitioner with oncology certification and a healthcare freelance writer with an interest in educating patients and the healthcare community.

Originally written by Pam Stephan
Pam Stephan is a breast cancer survivor.
Learn about our editorial process