Study Finds Skin Cream is OK Before Radiation Therapy Despite Common Recommendation

Patients can apply topical skin treatments in moderation before radiation therapy despite common advice from health care providers not to, according to study findings published in JAMA Oncology.

The study from Perelman School of Medicine at the University of Pennsylvania (UPenn) found there was no difference in the radiation skin dose with or without the creams.

Nearly two-thirds of all patients with cancer in the United States will undergo radiation therapy as part of their treatment, and as many as 90 percent of those patients will experience radiation dermatitis — a rash or burn on the skin, according to a UPenn press release.

“Patients are typically advised to avoid topical agents for several hours before daily radiotherapy out of concern that topical agents might increase the radiation dose to the skin,” lead author Brian C. Baumann, M.D., an adjunct assistant professor of radiation oncology at UPenn, said in an interview with CURE. “This recommendation came into practice in the era of orthovoltage radiation from the 1920s to 1950s, which delivered a higher dose to the skin. With modern mega-voltage radiation treatments that deliver less dose to the skin, this recommendation may no longer be relevant.”

Researchers surveyed more than 200 individuals (108 clinicians and 133 patients) to determine how widespread the advice to avoid topical agents before radiation was among both groups. They were asked to complete 18 and 24 questions, respectively, online from Jan. 15, 2015 to March 15, 2017. Ninety-one percent of doctors and nurses who regularly manage radiation dermatitis reported that they tell patients not to use skin creams during the hours before radiation treatment. Among patients, 83 percent said they received this guidance from their health care providers.

However, researchers found that if the creams were applied moderately rather than heavily before treatment, then it did not increase the amount of radiation that the skin receives and potentially can improve quality of life for patients.

To examine this, the researchersstudied Aquaphor, an over-the-counter petroleum-based ointment, and silver sulfadiazine cream, which is prescription-only. Each cream was applied to a paper that mimics the interaction of radiation to the body, and one paper had nothing applied to it. Then they applied radiation and measured how much was absorbed. This was repeated using different degrees of thickness for both products.

“Our survey results demonstrated that avoiding topical agents prior to radiation treatments is still widespread,” said Baumann, who also currently serves as an assistant professor of radiation oncology at Washington University in St. Louis. “We found no increase in the measured surface dose in the presence or absence of topical agents, except in the case of a very thick application of a skin cream or ointment, which represents an extreme scenario that we did not encounter in our clinic.”

Looking ahead, Baumann hopes to explore novel therapies to treat radiation dermatitis more effectively. “These findings mean that patients undergoing radiotherapy can apply topical agents for their radiation dermatitis at any time that they would like, including in the hours before each radiotherapy treatment, provided they do not apply a very thick layer of cream or ointment just prior to radiation,” he added.