ERBB2 and neoplasm: Of the 319 HER2+ residual tumor samples, 213 were found to be HER2 3+ by IHC, 92 were found to be HER2 2+ by IHC and ISH-amplified, 9 were diagnosed as HER2 1+ by IHC and ISH-amplified, and 5 were diagnosed as HER2 0 by IHC and ISH-amplified.