Staining was scored by three observers in keeping with the accepted method in the UK and USA as follows: HER2 0− negative no staining or membrane staining is < 10% of cancer cells, 1+ negative faint/barely perceptive membrane staining in more than 10% of the cancer cells, 2+ equivocal weak to moderate complete membrane staining in more than 10% of cancer cells or < 30% with strong complete membrane staining, and 3+ is considered positive and involves strong complete membrane staining in more than 30% of cancer cells [30]. This evidence concerns the gene ERBB2 and cancer.