The Integration of a Reminder App into a Skincare Routine to Prevent Inflammatory Skin Reactions During Radiation Therapy for Breast Cancer

Treatment for early-stage breast cancer (stages 1–2) typically involves breast-conserving surgery with the goal of a complete recovery. To reduce the risk of recurrence, systemic therapy (neoadjuvant) is administered before surgery in certain cases. In many cases, and depending on certain risk factors, further therapy may be administered after surgery (adjuvant therapy) to reduce the risk of residual disease or recurrence. Radiation therapy is one treatment option in this context. The goal is to damage the cancer cells using high-energy radiation. In hypofractionated radiation therapy, the total duration of treatment is shortened by increasing the radiation dose per session. However, the radiation can also damage skin cells, among other things, which can lead to inflammation of the skin (“radiation dermatitis”). Severe redness, mild swelling, and flaking of the affected area are already classified as Grade 2. To reduce the risk of this side effect, daily skin care is recommended.

The aim of this study is to investigate whether the use of a reminder app for skin care can reduce the frequency of inflammatory skin reactions (Grade 2 and above) during radiation therapy. As part of the study, all patients receive hypofractionated radiation therapy at a dose of 40 gray (Gy), divided into 15 sessions over three weeks (five sessions per week). For patients aged 50 or younger, or those over 50 with an increased risk of recurrence, an additional 10 Gy of radiation to the tumor will be administered beforehand over five sessions (a so-called “radiation boost”). In addition to radiation therapy, systemic cancer therapy (including anti-hormone therapy) may be part of the treatment strategy.

As part of the study, patients are divided into different subgroups based on three markers: 1. Extent of radiation treatment (irradiation of the breast ± lymph nodes), 2. Administration of an additional, targeted radiation dose following standard radiation therapy (“radiation boost”), and 3. Presence of at least one risk factor for inflammatory skin reactions. Subsequently, patients in each subgroup are randomly assigned to two treatment arms. The study is open-label, meaning that both the medical staff and the patient know which treatment arm they have been assigned to. Treatment arm A follows the standard skin care regimen and is supported by a reminder app on the smartphone. The app reminds patients four times a day to perform their skin care routine and assists them with illustrated instructions. In addition, patients receive information sheets on the correct use of the skin care regimen, and within the app, they can earn points by performing their skin care routine regularly and on time. Treatment arm B follows only the recommended standard skin care regimen and is not supported by the app. The exact skin care recommendations may vary among the different study sites. The treatments, examinations, and questionnaire-based interviews as part of the study will take place over a period of up to approximately four weeks.

Women aged 18 and older with breast cancer and an indication for hypofractionated radiation therapy following surgical removal of the tumor are eligible to participate in this study. Pregnant and breastfeeding women are not permitted to participate in the study.