Prophylaxis with topical antimicrobial therapy may reduce the severity of acute radiation dermatitis

New research suggests that acute radiation dermatitis (ARD) may involve common skin bacteria, not radiation burns, and topical antimicrobial therapy may be associated with breast cancer and breast cancer, according to two published studies. It has been suggested that it may be useful in preventing the severity of head and neck cancer patients.of JAMA Oncology.^1,2

“Until now, it was thought that ARD was simply caused by radiation-induced skin burns, which meant there wasn’t much we could do to prevent it,” said Beth, director of the Montefiore Einstein Cancer Center Supportive Oncology Dermatology Department. Dr. N. McClellan said: The director of dermatology at Montefiore Health System and the Albert Einstein College of Medicine said in a news release. “The readily available treatments we have developed and tested in clinical trials have the potential to help hundreds of thousands of people around the world each year. [United States] From severe ARD and its intolerable symptoms [adverse] effect [AEs]”³

Results from a phase 2/3 trial (NCT03883828) showed that more than half of patients receiving antimicrobial therapy experienced mild to moderate ARD (n =39) but developed wet desquamation, the most severe ARD It was shown that there were no patients. And it destroys the skin and causes sores. In the control group (n = 38), 23.7% of patients experienced severe ARD.³

Antimicrobial therapy consisted of body cleaners chlorhexidine gluconate 4% and mupirocin 2% nasal ointment twice daily for 5 days before radiotherapy and continued every other week during radiotherapy.

The study enrolled 77 patients undergoing radiation therapy, of whom 75 had breast cancer and 2 had head and neck cancer. Participants were randomly assigned to receive either antimicrobial therapy or standard care with usual hygiene and moisturizing treatments. Mean age was 59.9 years, 75 were female, and most patients were black (33.7%) or Hispanic (32.5%).¹

For radiotherapy, the median dose was 52.4 Gy (IQR, 42.4-52.4). It delivered in a median of 20 fractions (IQR, 16-20).

Finally, mean ARD grades were significantly lower in patients belonging to the antimicrobial therapy cohort than in patients receiving standard care (P. = .02). Of the patients who received this regimen, 69.2% reported treatment adherence and 1 patient (2.5%) reported her AE (pruritus) related to treatment.

“Because our treatment is simple, cheap, and easy, we believe it should be used in everyone undergoing radiation therapy first, without the need to test individuals first. Staphylococcus aureus [SA]said McClellan. “We expect this to completely change the protocol.” [individuals] I am undergoing radiation therapy for breast cancer. ”

Rethinking the Origins of Radiation Dermatitis

A concurrently published study found that SA bacteria are associated with severe ARD. JAMA Oncology.2 In a cohort of 76 patients undergoing radiotherapy for cancer, 48.3% of patients (n = 29) who developed severe ARD also tested positive for SA after starting treatment. By comparison, he tested positive for SA in only 13% of those who experienced mild ARD.

Colonization of SA is usually found on the skin, especially on the nose and armpits. For most people, this is harmless, but it can lead to infections if the skin is damaged. This can weaken skin structures at the treatment site during radiation therapy, so infections can occur.

Because SA is associated with skin disorders that cause skin breakdown, such as eczema, researchers hypothesized that SA may also be implicitly involved in the development of ARD. To test this theory, they analyzed 76 patients being treated at the Montefiore Einstein Cancer Center and collected bacterial cultures from these patients before and after radiation therapy. The study period was from July 2017 to May 2018 and included patients aged 18 years and older with breast or head and neck cancer. All patients received fractionated radiotherapy (at least 15 doses) with curative intent.²

Cultures were collected from the inside of the nose, the skin in the irradiated area, and the skin on the side of the body that was not exposed to radiation. ARDs were graded according to the Common Terminology Criteria for Adverse Event Reporting, version 4.03.

All 76 patients developed ARD, 47 patients developed grade 1 (61.8%), 22 developed grade 2 (28.9%), and 7 developed grade 3 (9.2%). ). Baseline nasal SA colonization was associated with grade ≥2 ARD compared with grade 1 ARD (P. = .02).²

“This study clearly shows that SA plays a major role in ARD,” McClellan said. “The good news is that we have many tools to fight this germ.”

References

1. Kost Y, Deutsch A, Mieczkowska K, et al. Bacterial decolonization for the prevention of radiation dermatitis: a randomized clinical trial. JAMA Ongol. Published online May 4, 2023. doi:10.1001/jamaoncol.2023.0444
2. Kost Y, Rzepecki AK, Deutsch A, et al. Association between S. aureus colonization and severity of acute radiation dermatitis in breast or head and neck cancer patients.. JAMA Oncol. Published online May 4, 2023. doi:10.1001/jamaoncol.2023.0454
3. A simple antibacterial treatment solves serious skin problems caused by radiation therapy. news release. Montefiore Einstein Cancer Center. May 4, 2023. Accessed May 15, 2023. https://www.prnewswire.com/news-releases/a-simple-antibiatible-treatment-solves-a-severe-skin-problem-caused-by-radiation-therapy-301816414.html