Central pathology laboratory review of HER2 and ER in early breast cancer: an ALTTO trial (BIG 2-06/NCCTG N063D (Alliance)) ring study Ann E. McCulloughPatrizia Dell'OrtoMonica M. ReinholzRichard D. Gelber • Amylou C. DueckLeila RussoRobert B. JenkinsStefania Andrighetto •