Can Aligning Radiotherapy for Breast V\Cancer with Circadian Rhythms Minimize Side Effects?

In In The News by Barbara Jacoby

By: Sarah Rosenthal


Radiation, or radiotherapy, for breast cancer patients is one of the most common forms of treatment, and comes with some uncomfortable and harmful side effects. A recent study from the University of Leicester in England has demonstrated that side effects can be minimized by changing the time of day that the treatment is provided. Researchers “personalized” the treatment for the more than 1,000 patients in the study by adjusting the timing of radiation to the patients’ circadian rhythms. This process seems to both increase radiation’s effectiveness and minimize some of its side effects. Side effects of radiation are referred to as radiotoxicity, and can include skin pain, burning and swelling directly after treatment; it can also cause nerve damage and weaken bones in the long term.

Approximately 90% of operable breast cancer patients undergo radiation, and around 45% experience what the researchers called “nasty side effects” (opposed to the usual, milder, side effects).

According to the researchers, most of the care today is centered around the availability of treatment, not what is best for the patient.

Researchers studied 1,007 participants who had previously undergone radiotherapy or were currently receiving it. They were tested for two gene variants to determine their circadian rhythm as well as their response to treatment in the short and long term. The radiotherapy was timed differently for different patients to match their bodily cycles. Results showed that side effects were worse when radiotherapy was administered in the morning. For example, 24% of patients had bright red skin in the morning, compared to only 11% in the afternoon.

The researchers believe that altering the time of day that treatment is administered could change the whole course of cancer treatment for the better. Further trials need to be conducted to solidify the presented results before they can be worked into clinical settings in the future. Published Jan. 2, 2019. Via The Telegraph.