Proton beam therapy side effects

Although research is limited, proton beam therapy (PBT) seems to have fewer side effects than standard radiotherapy. This is because PBT targets cancer cells more accurately so that less healthy tissue gets harmed.

The side effects of proton beam therapy vary according to which part of the body is being treated. They also depend on:

  • the dose and duration of treatment
  • any other existing conditions
  • any previous surgical procedures
  • whether or not you are also having chemotherapy

Side effects can happen during the therapy, immediately afterwards or months to years later.

Common side effects can be sore skin, hair loss if the head is being treated, sore mouth if the face is being treated, diarrhoea, nausea and vomiting if the pelvis and abdomen are being treated and general tiredness.

Your consultant in the UK and the doctors at the proton therapy centre will give you more detailed information about the risks of possible long-term side effects before treatment starts. Doctors at the therapy centre will closely monitor any side effects during treatment and will be available to answer any concerns you may have.

Updated March 2018, next review due 2021.