What is the yield of regional lymph node dissection following sentinel lymph node involvement in patients with breast cancer?

Abstract

10782 Background: Sentinel lymph node is a minimally invasive and accurate staging procedure for patients with invasive breast cancer. Histological SLN involvement with cancer cells requires regional lymph node dissection. Aim: To verify if subgroups of patients with sentinel lymph node involvement in which the risk of histological involvement of additional regional lymph nodes is minimal can be identified. Methods: Ninety six consecutive patients with invasive breast cancer and tumour size less than two centimeters by mammography, had lymphoscintigraphy with colloidal 99Tc and radioisotope-guided sentinel lymph node biopsy in the University Hospital of Zaragoza from 1999 to 2005.Pathological assessment included serial sections of the sentinel lymph node with inmunohistochemistry for cytokeratins in selected cases.39 patients had histological involvement and are presented in this analysis. Results: All 39 patients were females. Median tumour size was 20 mm (range 5–52) Median number of resected sentinel lymph node was 2 (range 1–5) Median number of involved sentinel lymph node was 1 (range 1–4) Regional lymph node dissection was performed in all patients (Axillary dissection in 31; internal mammary dissection in 1, both in 7). Median number of nodes was 13 (range 2–34) At least 1 additional involved lymph node was found in 19 patients (48%) We have correlated patient age, menopausal status, pathological tumour size, histological grade, estrogen receptors, progesterone receptors and Her2 with the risk of histological lymph node involvement in regional lymph node dissection. Conclusions: Tumour size was significantly associated to such risk: No significant financial relationships to disclose.