Early Breast Cancer and Distant Metastases
Widespread screening coupled with advances in imaging technologies has resulted in earlier detection of breast cancer. Consequently, more than half of the women currently presenting with breast cancer in the US have an early-stage form of the disease.10 Early-stage invasive breast cancer is defined as breast cancer that has not spread beyond the breast or the axillary lymph nodes, and includes ductal carcinoma in situ, stage I, stage IIA, stage IIB, and stage IIIA breast cancers (see Table 1).9
T0 = primary tumor cannot be assessed; Tis = carcinoma in situ; T1 = tumor 2cm or less in greatest dimension (includes microinvasion 0.1cm or less in greatest dimension, T1mic); T2 = tumor more than 2cm but not more than 5cm in greatest dimension; T3 = tumor more than 5cm in greatest dimension; M0 = no distant metastasis; N0 = no regional lymph node metastasis; N1 = metastasis to movable ipsilateral axillary lymph node(s); N2 = metastases in ipsilateral axillary lymph nodes fixed or matted, or in clinical apparent ipsilateral internal mammary nodes in the absence of clinically evident axillary lymph node metastasis. Adapted from National Comprehensive Cancer Network (NCCN), Practice Guidelines in Oncology, Breast Cancer v.2. 2007, 2006.