Yang et al found that breast ductal carcinoma patients with positive expression of TNC has a shortened overall survival compared to the negative group,[19] while diametrically opposing conclusions were drawn by Shoji and colleagues.[28] This phenomenon may attribute to different sources of TNC because a functional difference in TNC may exist between the cancer cells and stromal cells.[20] In this study, we found that positive features of TNC expression were mainly localized in the cytoplasm of tumor cells and extracellular matrix. This evidence concerns the gene TNC and breast ductal adenocarcinoma.