This prospective non-interventional comparator study is to collect data on the clinical effectiveness and compliance of Ectoin® Mouth Wash solution (EML03) and to proof superiority to a well-established medical device on the market in the prevention of radiation-induced mucositis. The study doesn´t intervene with routine treatment strategy.

Inclusion Criteria:

• Individuals regardless of gender older than 18 years
• Patients diagnosed with squamous cell carcinomas [SCCHN] without metastases of other nonhead and nonneck tumors
• Patients receiving radiotherapy with a Karnofsky performance index >70%
• Absence of any sign of oral mucositis at baseline (visit 1)
• A definitive or postoperative treatment
• Radiation therapy dosage: Limitation dose rate of 60-70 Gy
• Radiotherapy of 6-7 weeks duration

Exclusion Criteria:

• Subjects younger than 18 years
• Hypersensitivity to Ectoin® or any of the other ingredients of the mouth wash
• Pregnancy or breastfeeding women
• Any disease that can, in the opinion of the treating physician, affect the outcome of the observational trial
• Patients who had a history of previous radiotherapy in head-neck region or chemotherapy
• Massive alcoholic anamnesis
• Massive smoker >20 cigarettes per day at present