Radiation therapy for basal and squamous cell skin cancers

Radiation therapy uses high-energy rays (such as x-rays) or particles (such as photons, electrons, or protons) to kill cancer cells. The radiation is focused from outside the body onto the tumor.

When radiation therapy is used to treat cancers on the skin, it is often done with a type of radiation called electron beam radiation. It uses a beam of electrons that only penetrate as far as the skin. This helps limit the side effects to other organs and body tissues.

Getting radiation treatment is much like getting an x-ray, but the radiation is stronger and aimed more precisely at the cancer. The procedure itself is painless. Each treatment lasts only a few minutes, although the setup time – getting you into place for treatment – takes longer.

If a tumor is very large or is on an area of the skin that makes surgery difficult, radiation may be used as the primary (main) treatment instead of surgery. Primary radiation therapy is often useful for some patients who, because of poor general health, cannot have surgery. Radiation therapy can often cure small non-melanoma skin cancers and can delay the growth of more advanced cancers. Radiation is also useful when combined with other treatments. It is particularly useful for Merkel cell carcinoma.

In some cases, radiation can be used after surgery as an adjuvant (additional) treatment to kill any small areas of remaining cancer cells that may not have been visible during surgery. This lowers the risk of cancer coming back after surgery. Radiation may also be used to help treat non-melanoma skin cancer that has spread to lymph nodes or other organs.

Side effects of radiation can include skin irritation, redness, drying, and hair loss in the area being treated. With longer treatment, these side effects may get worse. After many years, new skin cancers sometimes develop in areas previously treated by radiation. For this reason, radiation usually is not used to treat skin cancer in young people. Radiation is also not recommended for people with certain inherited conditions (such as basal cell nevus syndrome or xeroderma pigmentosum), who may be at higher risk for new cancers, or for people with connective tissue diseases (such as lupus or scleroderma), which radiation might make worse.

For more general information about radiation therapy, please see our document, Understanding Radiation Therapy: A Guide for Patients and Families.