Stage III melanomas are tumors that have spread to regional lymph nodes or have developed in-transit deposits of disease, but there is no evidence of distant metastasis. Stage III melanoma is regional melanoma, meaning it has spread beyond the primary tumor (local) to the closest lymph nodes, but not to distant sites. There are four subgroups of Stage III melanoma: IIIA, IIIB, IIIC, IIID. Stage III is invasive melanoma.