p-S2448-mTOR expression as determined by immunohistochemistry is inversely related to P7-score in ER + primary breast cancer. Tumors were dichotomized into high P7-score (>3) and low P7-score (<3). The histograms show mean ± SEM for the two groups. The median H -scores were significantly different between the two groups for p-S2448-mTOR but not total mTOR using a Mann–Whitney two tailed statistical analysis. ER, estrogen receptor; mTOR, mechanistic target of rapamycin; p-S2448-mTOR, mTOR phosphorylated on serine 2448; SEM, standard error of the mean.