Determination of HER2 gene status by fully automated fluorescence microscopy.

OBJECTIVE: To examine fluorescence in situ hybridization (FISH) in HER2 amplification in response rates to trastuzumab therapy and both taxane and anthracycline-based chemotherapy regimens. STUDY DESIGN: A total of 400 tumor sections were analyzed over an 8-month period. The sections were hybridized with probes for the HER2 gene and chromosome 17 centromere using standard FISH methods and analyzed on an automated fluorescence microscopy system. RESULTS: Reliable and valid methods for identification of the patients that will respond to treatment with trastuzumab are needed in order to achieve maximum therapy efficacy and maintain cost efficiency. FISH-based analysis is potentially an objective and reproducible approach to determination of HER2 gene status; however, manual FISH counting is a laborious task and subject to inter and intraobserver variability. CONCLUSION: The system described in this paper is a valuable tool in providing a consistent approach to the interpretation of breast tumor tissue analyzed by FISH analysis. In addition to consistency, an automated system provides a record of the images produced that can be of immediate benefit in multiple review of a difficult or equivocal case and long-term benefit in terms of providing a permanent case record.

DNA ploidy and cell cycle analysis in breast cancer.

During the past 10 years there has been considerable interest in the application of new technologies to identify human malignancy and predict disease outcome. Markers of cell proliferation and the technologies of flow cytometry and image analysis for the determination of DNA total content in human tumor cells have been studied in breast cancer for 20 years. In this review, the uses and limitations of these technologies for the determination of ploidy status are discussed. This review also considers the prognostic significance and potential clinical utility of ploidy measurements, S phase calculation, and individual cell cycle regulatory biomarker expression levels.