Study Examines Topical Agents Before Radiation Therapy

Background on Radiation Dermatitis

A recent study published in JAMA Oncology by Baumann and colleagues explored whether patients should refrain from using topical agents several hours before undergoing radiation therapy. Most patients receiving radiation therapy experience some degree of radiation dermatitis, which involves skin damage. In addition, radiation therapy may lead to symptoms such as pain, discomfort, pruritus (itchy skin), and infections. To mitigate these complications, patients often use various topical agents, including skin creams, which may require frequent application.

Concerns About Topical Agents

Medical professionals have expressed concerns that these topical agents might significantly enhance the radiation dose received by the skin. Consequently, many doctors have recommended that patients avoid using topical agents several hours prior to radiation therapy. These concerns trace back to the early 1950s when radiation therapy typically involved exposing the skin to higher doses of radiation. In contrast, current radiation therapy employs much lower doses, raising questions about the necessity of avoiding topical agents beforehand.

Research Methodology

The study by Baumann and colleagues aimed to investigate if the application of topical agents prior to radiation therapy increases skin radiation exposure. The researchers first surveyed 108 clinicians and 133 patients to determine the percentage of doctors still advising patients against using topical agents before therapy.

Additionally, they conducted experiments utilizing a tissue-equivalent phantom to measure the radiation dose experienced by the skin after therapy, both with and without the application of two common topical agents: a petroleum-based ointment and silver sulfadiazine cream. Preclinical experiments in mice were also performed to evaluate whether the use of topical agents exacerbates skin damage post-therapy by assessing DNA damage and cell death.

Study Findings

The survey results revealed that most doctors continue to recommend that patients avoid topical agents several hours prior to radiation therapy. However, the findings indicated that such recommendations may be unnecessary, as the presence of topical agents did not significantly elevate the radiation dose to the skin during treatment. These results were consistent with preclinical studies conducted on animal models, which demonstrated that radiation therapy had a similar impact on mouse skin, irrespective of the application of topical agents.

Conclusion and Implications

In summary, while a significant number of doctors still advise patients to refrain from using topical agents before radiation therapy, the current study’s data suggest that these guidelines may not be warranted. This research could have important implications for patient health and quality of life, as it may allow patients to use topical agents as needed without restrictions.

Written by Haisam Shah, BSc

Reference: Baumann, B. C., Verginadis, I. I., Zeng, C., Bell, B., Koduri, S., Vachani, C., … & Metz, J. M. (2018). Assessing the validity of clinician advice that patients avoid use of topical agents before daily radiotherapy treatments. JAMA Oncology.