Aguilar–Mahecha A, et al. – This study determined the challenges in tissue collection for biomarker studies for breast cancer. It was investigated that RNA–later made the histopathological analysis of tumor content difficult. It also yielded less DNA than fresh snap frozen samples. Hence, high–quality tissue procurement could be best accomplished if at least three image–guided core biopsies were obtained per sample, each of these cores were inspected for tumor cellularity and that at least few of them appeared to be freshly snap frozen in liquid nitrogen.