Sentinel lymph node and clinically negative axillary node status was compared with well-known clinicopathological characteristics such as tumor size, histologic and nuclear grade, lymphovascular invasion, steroid receptor, and HER-2 status in patients with breast cancer (pT1 and pT2). Positive sentinel lymph nodes were found in 29 of 100 patients: 19 with metastases detected by hematoxylin and eosin staining and 10 with micrometastases confirmed by immunohistochemistry with cytokeratin. Positive sentinel lymph nodes were present in larger carcinomas (P < 0.03), more frequently in tumors with negative PR status (P < 0.037) and evident lymphovascular invasion (P < 0.002). Lymphovascular invasion was also associated with breast cancer of higher histologic (P = 0.011) and nuclear grade (P = 0.039). Tumor size and the presence of lymphovascular invasion were found to be significant predictors of pathologically positive sentinel lymph node in T1 and T2.