Influence of Sentinel Lymph Node Metastasis on the Overal Survival and Disease-Free Survival in Patients with Breast Cancer

Abstract

OBJECTIVE: To assess the association of clinical, pathological, immunohistochemical factors, size of the lymph nodes metastasis, disease-free survival and overall survival in patients with breast cancer submitted to sentinel lymph node biopsy. METHODS: The study population is composed of a retrospective hospital-based assessment of 1211 patients with primary tumors T1 and T2 submitted to SLNB between 1998 and 2011. Associations such as age, tumor size, tumor grade, RE/RP status, HER-2/neu, Ki-67, angiolymphatic invasion, metastasis size, disease-free survival and overall survival were assessed. RESULTS: The median age was 59 years and the median tumor sizes were 1,6 cm. Among patients considered clinically negative axillary, 32,8% of the sentinel lymph nodes (SLN) showed metastasis, being 81,9% of macrometastasis and 18,1 of micrometastasis (micro and isolated tumor cells). The association of age, tumor size, tumor grade, angiolymphatic invasion with the type of metastasis was observed in SLN. The disease-free survival was statistically influenced by the tumor size, angiolymphatic invasion, Ki-67 and the type of metastases, while the overall survival was influenced only by the presence of metastases. Multiple analyses showed that the type of SLN metastases influences the disease-free survival, but not the overall survival. Furthermore, the risk of recurrence increases 3,17 times when SLN shows macrometastasis. DISCUSSION: The prognostic significance of the SLN metastasis has being discussed. The association of age, tumor size, tumor grade, angiolymphatic invasion and recurrence with the type of SLN metastasis could be confirmed in accordance with other studies. Tumors greater than 2,0 cm, high proliferation rate (Ki67+), angiolymphatic invasion were associated with the finding of macrometastasis in the SLN and worse disease-free survival, indicating higher potential of metastatic cells. Nevertheless, these variables weren t associated with the overall survival, which was found statistically dependent on the occurrence of recurrent disease. Indeed, probably influenced by the effectiveness of administering adjuvant systemic therapy, CONCLUSION: Age, tumor size, histological degree and angiolymphatic invasion were associated with the type of SLN metastasis, whereas tumor size, angiolymphatic invasion, Ki-67 and type of metastasis influenced the disease-free survival. The overall survival was only associated with the presence of metastasis. There was no statistically significant difference between positive SLN (pN1mi, pN1) and negative SLN concerning the patient overall survival.