This study is a local, prospective, non-interventional, non-controlled, multicenter, observational study (regulatory postmarketing surveillance). Each physician will enroll patients who have received at least 1 dose of Yervoy, and each patient will be followed for up to 12 months. All patients will be evaluated for safety and effectiveness during Yervoy use (4 doses) and for 12 months from the first dose of Yervoy to confirm the safety profile of Yervoy under routine, daily practice