Trainable immunohistochemical HER2/neu image analysis: a multisite performance study using 260 breast tissue specimens.

Context: Aperio Technologies, Inc (Vista, California) provides a new immunohistochemistry (IHC) HER2 Image Analysis (IA) system that allows tuning of the intensity thresholds of the HER2/ neu scoring scheme to adapt to the staining characteristics of different reagents.

Objective: To compare the trainable IHC HER2 IA system for different reagents to conventional manual microscopy (MM) in a multisite study.

Design: Two hundred sixty formalin-fixed, paraffin-embedded breast cancer specimens from 3 clinical sites were assayed: 180 specimens stained with Dako's HercepTest (Carpinteria, California), and 80 specimens stained with Ventana's PATHWAY HER-2/neu (Tucson, California).

A multisite performance study comparing the reading of immunohistochemical slides on a computer monitor with conventional manual microscopy for estrogen and progesterone receptor analysis.

A multisite study was conducted to assess the performance of the Aperio digital pathology system (Aperio Technologies, Vista, CA) for reading estrogen receptor (ER) and progesterone receptor (PR) slides on a computer monitor. A total of 520 formalin-fixed breast tissue specimens were assayed at 3 clinical sites for ER and PR (260 each). Percentage and average staining intensity of positive nuclei were assessed.