[Stage I includes: IA (T1a, N0, M0); IB (T1b, N0, M0); (T2a, N0, M0). T1a: Melanoma is less than or equal to 1.0mm in thickness with or without ulceration. T1b: Melanoma is less than or equal to 1.0mm in thickness and level IV or V with ulceration. T2a: Melanoma 1.01-2.0 - mm in thickness, no ulceration. N0: No regional lymph node metastasis. M0: No distant metastasis. - 2003 ( NCI )]
UMLS (NCI) C0855015