Validation of in Vitro Method for Anti-MCPyV Immunotherapy on Patients With Cutaneous Merkel Cell Carcinoma

This study is testing a laboratory method to evaluate immune cells taken from patients with Merkel cell carcinoma — a rare and aggressive type of skin cancer often linked to the Merkel cell polyomavirus (MCPyV). The goal is to validate a test that could help researchers develop better immunotherapy treatments for this cancer in the future. **You may be eligible if...** - You are 18 years of age or older - You have been diagnosed with Merkel cell carcinoma of the skin - You are currently receiving local treatment, systemic treatment, additional therapy after initial treatment, or are in active follow-up for this cancer - You have health insurance coverage - You have been informed about the study and are not opposed to participating **You may NOT be eligible if...** - You are currently enrolled in another interventional clinical trial - You are under legal guardianship - You are pregnant or breastfeeding - You have declined to participate Talk to your doctor to see if this trial is right for you.