The heterogeneity of HER2 status is usually manifested by two conditions, one is the heterogeneity between the local and the tumor as a whole, which often represents the difference between biopsy specimens and the whole tumor sections in clinical setting; the other is the heterogeneity between the DNA level and protein level of HER2 status, which often represents the difference between FISH and IHC results. Here, ERBB2 is linked to neoplasm.