The number of positive axillary lymph nodes (LNs) is the only node-related factor for prognostic evaluation of breast cancer recognized by AJCC (TNM staging). (= 0.001), compared to the metLN (HR 0.09, = 0.052) and CSCA (HR 2.24, = 0.323). 1. Introduction Breast malignancy was the most common malignancy in women in North America in 2010 2010 . The involvement of axillary LNs by malignancy is one of the most important factors for malignancy staging, treatment, and prognosis [2C5]. The surgical excision of the primary cancer and the axillary LN dissection has been considered as part of the standard management of invasive breast cancer [6C8]. Counting the number of positive axillary LNs was utilized for TNM staging , and it is the only node-related factor for the evaluation of breast cancer recognized by American Joint Committee on Malignancy (AJCC) . In general, evaluating 10 or more LNs is ideal for accurate assessment and the staging of breast malignancy [6, 7]. Besides LN staging, various other essential prognostic elements connected with breasts cancer tumor are tumor size similarly, histological quality, and hormone receptor position . Regarding to AJCC, predicated on the amount of positive LNs (metLN), sufferers are split into three N levels: N1 (1C3 positive LNs), N2 (4C9 positive LNs), and N3 (>9 positive LNs). There are a few factors of minimal tumor participation such as for example isolated tumor cells (<0.2?mm or <200 tumor cells) and micrometastasis (>0.2?mm and/or >200 tumor cells and <2?mm) in N0 and N1,  respectively. Nevertheless, the quantitative requirements never have been regarded in the AJCC staging program in positive LNs with cancers involvement higher than 2?mm. For instance, every included LN GS-9350 is certainly counted as positive without respect to the GS-9350 quantity of tumor which runs from a little microscopic concentrate to a near total substitute of the complete LN. Furthermore, there is absolutely no great way of managing a big matted LN in today's pathologic TMN staging program, even though scientific stage N2 is certainly applied with the current presence of matted LNs . In these circumstances, the metLN might not totally reflect the degree of tumor involvement in the LNs. To address this problem, we quantified the metastatic tumor volume by measuring cross-sectional malignancy areas (CSCAs) in the positive axillary LNs using computer imaging system. The positive LN percentage (LNR, defined as the percentage of the metLN to the total quantity of LNs examined) or the percentage of positive axillary LN was recently reported to be a strong predictor of breast cancer survival by several studies [12C21]. Multivariate analysis in these studies showed that LNR typically outperformed GS-9350 N stage in predicting Rabbit polyclonal to ACTR5 survival of breast malignancy individuals. Our study evaluated three node-related factors: metLN/N stage, LN CSCA, and LNR, and their association with prognosis. Our goal was to retrospectively compare these different methods and to determine the most significant LN-related predictor of breast cancer survival. We also evaluated additional risk factors including age, tumor size, T stage, histological grade, hormonal status, and extracapsular extension (ECE) of axillary LNs using univariate and multivariate analysis. 2. Materials and Methods The surgical reports and the medical records of 292 breast cancer individuals diagnosed between 1998 and 2000 in our institution were retrospectively analyzed. The time framework of 1998C2000 is definitely selected in that it allows at least a 10-12 months followup of the survival data. Information gathered for each patient includes age, tumor characteristics such as histologic grade, tumor size, T stage, metLN, N stage, total number of LNs examined, estrogen (ER) and progesterone receptor (PR) manifestation of tumors by immunohistochemical staining, and ECE of positive LNs. All the tumors were graded according to the Nottingham combined histologic grade. All the LNs are either bisected or serially sectioned into 2?mm thickness and submitted for histologic exam. ECE is defined by the obvious penetration of malignancy cells through the capsule of the LNs. The degree of metastatic malignancy including LNs was quantified in mm2 by measuring the area of malignancy in these LNs (using Software Imaging System Olympus, MicroSuite 5, Pathology Release). A screenshot of the malignancy area measurement on a cross-section of an LN using the software is shown in.