Stage II includes: IIA: (T0, N1, M0); (T1, N1, M0); (T2, N0, M0); IIB: (T2, N1, M0); (T3, N0, M0). T0: No evidence of primary tumor. T1: Tumor measuring 20 mm or less in greatest dimension. T2: Tumor measuring more than 20 mm, but not more than 50 mm in greatest dimension. T3: Tumor measuring more than 50 mm in greatest dimension. N0: No regional lymph node metastasis is identified or isolated tumor cell clusters (ITCs) are identified only. N1: Tumor with micrometastases; or metastases in 1-3 axillary lymph nodes; and/or clinically negative internal mammary nodes with micrometastases or macrometastases by sentinel lymph node biopsy. M0: No clinical or radiographic evidence of distant metastases. Imaging studies are not required to assign the M0 category. (AJCC 8th ed.) [from
NCI]