Ninety-seven cases were excluded: 45 had a HER2-positive FISH result from a biopsy at an outside facility; 27 represented the second or greater HER2-equivocal FISH result in the same patient; 4 were HER2-equivocal FISH results from a non-breast cancer, all cancers of gastrointestinal origin; 3 occurred in patients with synchronous primary cancers; 14 were missing survival data; and 4 occurred in patients enrolled in a clinical trial of the E75 vaccine to boost anti-HER2 therapy. Here, ERBB2 is linked to breast cancer.