ERBB2 and neoplasm: The generated results are conflicting.[7–9] Some reports have indicated that neuroendocrine differentiation (NED) in the tumor, assessed either with immunohistochemistry or with measuring the concentracion of the product of the tumor cells in the peripherial blood, is a significant prognostic parameter associated with survival after endocrine therapy.[10–12] Basic research has shown that HER-2 (c-erbB-2) over-expression is associated with increased aggressiveness of the tumor.