CD44 and breast neoplasm: CD44+/CD24- cells have been observed in 63% of basal-like subtype (SR-HER2- basal-like) breast tumors.[20] Although we did not observe a significant difference in the proportion of CD44+/CD24- cells in samples from tumors with and without basal-like features, we found that the CD44+/CD24- subpopulation was higher in samples of recurrent and metastatic tumors with basal-like features.