The EORTC QLQ-C30 questionnaire contains 30 questions and assesses the quality of life of oncological patients multidimensionally over 10 subscales. Since oncology has a broad spectrum of tumor diseases and thus clinical pictures, it is, however, counted among the rather non-disease-specific questionnaires. However, in order to also consider oncological patients in a disease-specific way, further suitable modules were developed as PRO instruments for the QLQ C30, depending on the tumor disease. For example, there is the QLQ BR23 for patients with breast carcinoma or QLQ PR25 for patients with prostate carcinoma.2-3