Expression of truncated HER2 and its prognostic value in HER2-positive breast cancer patients.

Purpose: The purpose of this work was to assess the truncated form of human epidermal growth factor receptor 2 (HER2) such as p95-HER2 expression in HER2-positive breast cancer (BC) patients who developed metastatic disease after adjuvant treatment with a trastuzumab-containing regimen.

Patients And Methods: Thirty-two histologically diagnosed HER2-positive BC patients who developed distant failure after treatment with trastuzumab-based chemotherapy (CT) regimen as an adjuvant therapy were included in the study. Immunohistochemistry (IHC) method was used to analyze p95-HER2 expression in the formalin-fixed, paraffin-embedded (FFPE) blocks of the enrolled patients.