Urinary Microbiome as a Biomarker for Melanoma Diagnosis and Response Prediction to Systemic Tumour Therapy

This study looks at whether the bacteria naturally present in urine (the "urinary microbiome") can help doctors better understand melanoma, a type of skin cancer, and predict how well patients respond to treatment. In recent years, researchers have discovered that bacteria in the body-especially in the gut-can influence cancer development and how patients respond to therapy. However, very little is known about the bacteria in urine and whether they may also play a role in cancer. In this study, patients with melanoma who are starting treatment (such as immunotherapy or targeted therapies) will be asked to provide urine samples and stool samples at several time points, as well as answer questionnaires about their health and lifestyle. A group of people without melanoma will also provide urine samples for comparison. Researchers will analyze these samples to identify the types of bacteria present and how they change over time. They will then investigate whether certain bacterial patterns are linked to better or worse treatment outcomes. The study does not change the medical treatment patients receive. Participation mainly involves providing samples and filling out questionnaires, which represents only a small additional effort. The results of this study may help to identify new, non-invasive biomarkers that could improve early diagnosis and help doctors choose the most effective treatment for melanoma patients in the future

Inclusion Criteria: * melanoma with indication for systemic therapy * age above 18 * informed consent Exclusion Criteria: * \- inability to provide informed consent * antibiotic use (except for topical use) ≤ 8 weeks prior to screening * consumption of probiotic or prebiotic supplements within 4 weeks prior to screening * current diagnosis of any disease with systemic inflammation (e.g. cellulitis, herpes zoster, psoriasis, etc.) * for the case group: diagnosis of any active malignancy other than melanoma (except for basal cell carcinoma) * for the control group: diagnosis of any active malignancy (except for basal cell carcinoma)