Predicting axillary nodal positivity in 2282 patients with breast carcinoma

Axillary lymph node status continues to be the single most important progno stic variable for breast cancer survival despite significant progress in th e molecular and genetic characterization of breast malignancies. All patien ts with invasive breast cancer who underwent axillary lymph node dissection as part of their treatment were evaluated by 11 clinical and pathologic fa ctors, including the primary lesion's T category (TNM staging system), whet her the lesion was clinically palpable, the presence of lymphatic or vascul ar invasion, nuclear grade, estrogen and progesterone receptors, S-phase, a ge, HER2/neu overexpression, histology (infiltrating lobular or ductal), an d ploidy. A total of 2282 axillary dissections were performed: 391 in patie nts with ductal carcinoma in situ (DCIS) [3 of which (0.8%) contained metas tases] and 1891 in patients with invasive breast cancer [680 of which (36%) contained metastases]. Multivariate analysis of patients with invasive can cer identified four factors as independent predictors of axillary lymph nod e metastases: lymph/vascular invasion, tumor size, nuclear grade, tumor pal pability. Among a group of 189 patients with nonpalpable, non-high-grade in vasive lesions 15 mm or smaller without lymph/vascular invasion, only 6 (3% ) had metastases to lymph nodes. If any three of the favorable factors were present, lymph node positivity was 6% or less, Clinical and pathologic fea ture of the primary lesions can be used to estimate the risk of axillary ly mph nude metastases, Such risk assessment can be used for the treatment der ision-making process.