Predicting the likelihood of non sentinel lymph node metastases after a positive sentinel lymph node biopsy in a group of breast cancer patients treated at Tanta University Hospital

Background/Aim: Reliable predictors of axillary nodal involvement would enable a better selection of candidate patients for sentinel lymph node biopsy (SLNB) and possibly allow identification of patients with such a low risk of axillary sentinel lymph node (SLN) involvement to be even spared SLNB. In this study, our aim was to evaluate the factors associated with SLN involvement with estimation of the predictability of various clinicopathologic factors on non-sentinel lymph node metastases (NSLNM) in breast cancer (BC) patients with positive SLNB to spare a subgroup of BC patients and a positive SLNB completion of axillary lymph node dissection (ALND). Patients & Methods: A total of 851 patients with clinically node-negative early invasive breast carcinomas underwent breast conserving surgery or modified radical mastectomy and SLNB followed by ALND were included in this study during the period between December 2005 and September 2014. Characteristics of the patients, tumors and SLNs were studied and analyzed both Histopathologically and immunohistochemically. Results: Sentinel lymph nodes showed positivity in 366 cases (43%). In univariate analysis, there was statistical significant correlation with the proliferative fraction ≥16%, multicentric disease, HER-2 status, lympho-vascular invasion, tumour histology, tumor status, tumor grade, epithelial hyperplasia, and perineural invasion. There was no statistical significant correlation when looking at the age of the patients, estrogen receptor (ER) status, progesterone receptor (PR) status, ER/PR +ve tumors, menopausal status, triple-negative tumors, microcalcification and family history. In multivariate analysis, only the occurrence of peritumoral vascular invasion was independently related to this end point. Overall, 166 of 366 patients (45.4%) had additional NSLNM. In univariate analysis, there was a significant correlation between NSLNM and the size of SLN metastases (SLNM), multicentric disease, tumor status, tumor grade, perineural invasion, epithelial hyperplasia, lympho-vascular invasion, and patients with 2 or more involved SLNs. There was no statistical significant correlation when looking at the age of the patients, multifocality, ER status, PR status, ER/PR +ve tumors, menopausal status, histologic type, Her2/neu expression, proliferative fraction, triple-negative tumor, microcalcification and family history. In multivariate analysis, only, the size of SLNM, and the occurrence of peritumoral vascular invasion in the primary breast carcinoma were independently related to this end point. Conclusion: In patients with early invasive breast carcinomas, histopathologic features of the primary tumor and SLNs status might be used to tailor the loco-regional treatment. However caution is required as patients with the most favorable combination of predictive factors still have a risk for NSLNM and should be offered completion ALND. Thus evaluation of additional molecular markers may further help to stratify patients to a risk-adapted approach. [Hanan Shawky Gamal El-Deen, Mohamed Ali Mlees, Aymen Mohamed Elsaka. Predicting the likelihood of non sentinel lymph node metastases after a positive sentinel lymph node biopsy in a group of breast cancer patients treated at Tanta University Hospital. Life Sci J 2014;11(10):1022-1033]. (ISSN:1097-8135). http://www.lifesciencesite. com. 156