Lymph Node Ratio (LNR) as a predictive factor in addition to pNstaging in Syrian-breast cancer patients at diagnosis

Abstract

Background: Metastasis to the axillary lymph nodes is a key indicator of prognosis in breast cancer. Lymph node ratio (LNR) is reported to be superior to the absolute number of nodes involved (pN stage) in classifying patients at high versus low risk of death following breast cancer. Aim of the study: This prospective study investigated the predictive value of the lymph node ratio (LNR) compared with the number of positive lymph nodes (pN), serum C-reactive protein (CRP) levels, hormones status and other prognostic factors in Syrian -breast cancer patients. Patients and methods: 60 breast cancer patients aged between 32 to 77 years old, admitted in National hospital of Jableh (Lattakia-Syria) were selected from December 2015 until December 2016. LNR calculated as the ratio of the number of positive nodes to the total number of nodes excised, LNR had been categorized as low: (0 -0.2), intermediate: (>0.2 - 0.65), and high risk: (>0.65 – 1). Blood samples were collected for CRP levels on admission and measured by immunoturbidimetric determination, levels >5mg/l were considered positive. Estrogen-Receptor (ER), Progesterone Receptor (PR) and human epidermal growth factor receptor 2 (Her-2) expression were assessed. Results: Strong relationship was found between LNR-classification system and increased number of positive lymph nodes in breast cancer patients (P 4 were at high risk (100%) in comparison with patients with pN=4, and this difference was statistically important (P 0.05). Mean level of CRP was 5.38 ±2.94mg/l at low LNR, 7.29±5.21mg/l at intermediate LNR and 7.68±4.55mg/l at high LNR, but the differences were not statically significant (P=0.27). Patients at high risk according to LNR-classification were positive for ER-receptor (n=4, 100%, P=0.248), PR-receptors(n=3, 75%, (P=0.028) and for Her-2 receptor (n=3, 75%, P=0.963). Conclusion: Patients with number of positive lymph nodes more than 4 lymph nodes were at high risk according to LNR-classification system in comparison with patients with 4 lymph nodes or less as a predictive number of lymph nodes. LNR- classification was more interesting than pNstaging in comparison with level of serum CRP, but similar to other classic risk factor such as Grade, Stage, tumor size and age. LNR-classification system was interesting in positive PR-receptor expression patients as an added value of LNR for predicting future response to hormone therapy.