Factors Related with Axillary Lymph Nodes Metastases in T1 Invasive Ductal Carcinomas of the Breast

摘要

Purpose In breast cancer patients, information of the axillary nodal status is essential for staging, determining the necessity of systemic therapy, and predicting the prognosis. The necessity of an axillary lymph node dissection in small breast cancers is controversial. The aim of this study is to identify the factors associated with axillary lymph node metastases and to determine the necessity of axillary lymph node dissections in T1 invasive ductal carcinomas of the breast. Methods From the June 1991 to the March 2004, of a total 919 cases who underwent surgery for breast cancer in Korea University Hospital, 230 cases of T1 invasive ductal carcinomas were reviewed retrospectively. All subjects were classified as T1a, T1b, or T1c. The rate of axillary lymph node metastasis was calculated for each group and the factors that have a statistically significant correlations with axillary lymph nodes metastases were investigated. Results Of the 230 cases of T1 invasive ductal carcinomas, 22 cases were T1a, 27 cases were T1b, and 181 cases were T1c. Axillary lymph node metastases were encountered in 4 T1a case (18%), 5 T1b cases (18.5%), and 67 T1c cases (30.3%). The overall rate of axillary lymph node metastases rate in T1 was 33% (76/230). The T stage had a statistically significant correlation ( p =0.043) with the axillary lymph node metastases. Lymphovascular invasion of the tumor had a significant correlations with an axillary lymph node metastases ( p =0.032). The MIB-1 labeling index was increased according to the tumor size, and correlated with the presence of an axillary lymph node metastasis ( p =0.032, p =0.18). However age, hormone receptors, p53, HER2eu , and nm23 were not associated with an axillary lymph nodes metastasis. Conclusions The tumor size and the lymphovascular invasion could be significantly prognostic factors suggesting an axillary lymph node metastasis in T1 invasive ductal carcinomas. The MIB-1 immunostain was higher in the T1c cases. Therefore, a combination of the tumor size and MIB-1 immunostain would be an indicator for an axillary lymph node dissection. A sentinel lymph node biopsy may be of more benefit in T1a invasive ductal carcinomas of the breast.