• All patients must be either stage III (IIIB, IIIC, IIID) or stage IV (M1a, M1b, M1c) per American Joint Committee on Cancer (AJCC) 8th edition (Amin 2017) and have histologically confirmed cutaneous melanoma that is deemed completely surgically resectable in order to be eligible as described in the protocol.

• Patients with stage III melanoma must have clinically detectable disease that is confirmed as malignant on the pathology report. The pathology report must be reviewed, signed and dated by the investigator; this process will be confirmed during the interactive voice response system (IVRS) process as described in the protocol.

• Patients must be candidates for full resection with curative intent and must be able to be surgically rendered free of disease with negative margins on resected specimens at surgery. The treatment plan including date of surgery must be documented by the investigator prior to randomization.

• All patients must undergo full disease staging through a complete physical examination and imaging studies within 4 weeks prior to randomization. Imaging must include a computer tomography (CT) scan of the chest, abdomen, pelvis (if the primary tumor is on the head/neck then include a CT scan of head/neck), and all known sites of previously resected disease (if applicable) and brain magnetic resonance imaging (MRI) (or brain CT with contrast allowed if MRI is contraindicated).

• Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0 or 1