ERBB2 and breast cancer: We did not observe significant differences in survival in any of the breast cancer subtypes between low and high LAT1 expression; however, low LAT1 expression strongly tended to be a favorable prognostic factor in postmenopausal patients with ER+ (p = 0.05) and HER2- tumors (p = 0.10) In contrast, LAT1 did not approach significance as a prognostic factor in premenopausal patients with ER+ (p = 0.34) or HER2- tumors (p = 0.65).