Phase II Trial to Determine Role of Nodal Radiation Therapy after Sentinel Lymph Node Biopsy (SLNB) for Patients with High-Risk Sentinel Lymph Node Positive Melanoma Who Are Planned for Immunotherapy without Completion of Lymph Node Dissection (MelPORT)

The goal of this clinical research study is to learn if patients with melanoma who were found to have high risk sentinel lymph node(s) may benefit from radiation therapy when given after surgery. A sentinel lymph node is the lymph node located closest to the cancer. Biopsy of the sentinel lymph node helps determine if the cancer has likely spread to other parts of the body.