ERBB2 and cancer: We defined two cancer types according to ERBB2 expression: 1) primary tumor of patients with over-expression of ERBB2 (ERBB2high) and 2) primary tumor of patients with deficient expression of ERBB2 (ERBB2low), and we investigated the correlation of ERBB2 gene expression with the overall survival and disease-free survival of various primary tumors.