BACKGROUND: Axillary noed involvement is the single most important prognostic variable in patients with breast cancer. If axillary lymph node status of breast cancer patients could be accurately predicted from basic clinical information and from characteristics of their primary tumors, many patients could be spared axillary lymph node dissection. With the availability of numerous histologic prognosticators and new immunochemical prognostic indicators, it is time to consider eliminating routine node dissection for lesions more advanced than duct carcinoma in situ (DCIS). MATERIALS AND METHODS: Two hundred sixty-three patients with T1 invasive breast cancer were evaluated. All underwent axillary dissection, and the pathologic status of the nodes was known. The parameters of the primary tumor evaluated included age, size, family history, tumor palpability, nuclear and histological grade, hormone receptor status, lymphatic vessel invasion (LVI), and various tumor markers (bcl-2, cathepsinD, c-erbB2, E-cadherin, p53). RESULTS: Approximately 31.1% of the 656 patients with T1 breast carcinoma had axillary node metastasis. Four factors were identified as significant predictors of node metastasis: age35 or less (p=0.01), lymphatic vessel invasion (p<0.01), tumor palpability(p=0.02), and tumor size (p<0.01). However, independent predictors of lymph node metastasis in the multivariate logistic regression analyses were tumor size (p=0.04) and LVI (P=0.03). CONCLUSION: In conclusion, characteristics of the primary tumor can help assess the risk for axillary lymph node metastases. Selected patients who have 1cm or less without lymphatic vessel invasion considered to be at minimal risk of axillary node metastasis and might spared routine axillary dissection.