A randomized controlled trial comparing Urtica comp. gel (Swissmedic listed medication in the category of "Anthroposophic Medication without Indication") against standard skin care, examining its effect in prevention and treatment of radiation dermatitis in breast cancer patients under Radiation therapy.

Radiation dermatitis is one of the most common side effects of radiotherapy for cancer and affects around 95 % of patients receiving radiotherapy. Patients with breast cancer as well as patients with head and neck cancer are most frequently affected, due to the higher radiation dose to the skin, as compared to other cancer types.

Radiation dermatitis has a profound impact on the quality of a patient's life, due to pain and discomfort. Skin lesions bear a marked risk of infection. In addition, all these issues may be the cause of interruption of radiation therapy, resulting in inadequate disease treatment.

Despite a plentitude of studies researching local and systemic therapeutic approaches, currently no treatment (aside from local steroids which bear substantial side-effects) can be explicitly recommended.

Thus, further research, especially in therapeutic options with a positive side-effect spectrum would be highly beneficial.

Urtica comp. gel is a Swissmedic registered medication. It is e.g. applied in first and second-degree burn and scalding as well as sunburn and has been used in over 80 years with an excellent safety profile. Positive clinical experience in treating radiation dermatitis with Urtica comp. gel suggest studying this therapeutic option in a pilot trial.

Inclusion Criteria:

• Radiation therapy for Breast Cancer
• Age >= 18 years
• Written informed consent

Exclusion Criteria:

• Ulcerated cancer at beginning of radiation therapy
• Skin lesions in the radiation area before start of radiation therapy
• Known allergies, hypersensitivity or reactions against one of the constituents of the investigational product [5]
• Any neurological or psychiatric conditions that, in the evaluation of the treating physician, deem the patient incapable to participate in the study
• Other clinically significant concomitant disease states (e.g., renal failure, hepatic dysfunction, cardiovascular disease, etc.) as judged by the PI

The following criteria are exclusion criteria for the conduct of the radiation therapy, which is prerequisite for inclusion into the study. Thus, such patients will anyway not meet the inclusion criteria and are explicitly excluded from participation:

• Women who are pregnant or breast feeding
• Lack of safe contraception, defined as: Female participants of childbearing potential, not using and not willing to continue using a medically reliable method of contraception for the entire study duration, such as oral, injectable, or implantable contraceptives, or intrauterine contraceptive devices, or who are not using any other method considered sufficiently reliable by the investigator in individual cases.
• Please note that female participants who are surgically sterilised / hysterectomised or post-menopausal for longer than 2 years are not considered as being of child bearing potential.

Individual Patient data will not be shared.