Amplification or overexpression of HER2 oncoprotein plays an important role in the pathogenesis of various solid tumors [30], including upper gastrointestinal tract (stomach and gastroesophageal junction adenocarcinoma) [31], ovarian cancer, colon, salivary gland [32], lung cancer, and breast cancer [33]. This evidence concerns the gene ERBB2 and breast carcinoma.