Diagnostic Performance of Spot Urine Sample for the Monoclonal Components Detection in Patients With Multiple Myeloma

This study is evaluating whether a simple urine spot test can accurately detect and monitor abnormal proteins (called monoclonal components) in people with multiple myeloma — a type of blood cancer. The goal is to find a more convenient alternative to the standard 24-hour urine collection. **You may be eligible if...** - You have been diagnosed with multiple myeloma - You are starting a new line of treatment (any line), with at least 3 rounds of initial therapy - You have an abnormal protein level in your urine of at least 200 mg over 24 hours **You may NOT be eligible if...** - You are under legal guardianship or restricted from making your own decisions Talk to your doctor to see if this trial is right for you.