A Validation Study of Quantum Dot Multispectral Imaging To Evaluate Hormone Receptor Status in Breast Ductal Carcinoma In Situ (DCIS).
Jing Yu, Sara E Monaco, Rohit Bhargava, David D Dabbs, Kathleen M Cieply, Jeff L Fine. University of Pittsburgh Medical Center, PA
Background: The assessment of hormone receptors, including estrogen receptor (ER) and progesterone receptor (PR), has become a standard practice in breast cancer management. Currently, the recommended method is conventional immunohistochemistry (IHC) to detect protein expression levels. However, there are problems associated with the receptor analysis by IHC. The quantitative analysis (e.g. 1% of cells with weak signal for ER/PR positive result) has been subjected to interobserver variations; the need for multiple sections to evaluate each receptor individually by single-stained IHC often preclude the analysis on core biopsies with limited amount of invasive tumor or with microinvasive carcinoma. A more objective and efficient method would be optimal for the detection and quantification of breast cancer receptors. The aim of the study is to validate the quantitative analysis of ER and PR by Quantum Dot (QD) based IHC using multispectral imaging (MSI).
Design: A total of 17 cases of breast ductal carcinoma in situ (DCIS) with excisional biopsies or mastectomies were stained with conventional IHC and QD based IHC for ER and PR. For conventional IHC, a semi-quantitative H-score, as well as corresponding percentage of positive cells, was calculated. For QD-based IHC, three regions of interest (ROIs) were selected and captured for each case at 20x magnification for single-labeled ER (585nm) and PR (655nm), in addition to double labeled ER/PR. DAPI was used as a nuclear counterstain. Co-localization data between ER or PR and DAPI was analyzed by CRI Nuance FX multispectral imaging system using software version 2.10.
Results: Co-localization ratios of ER/DAPI or PR/DAPI by double-labeled QD-based IHC were compared with those by single-labeled QD-based IHC as well as either the H-score or percentage of positive cells by conventional IHC. For ER stains, there was good consistency between double- and single-labeled QD-based IHC (r = 0.93, P < 0.001), and QD-based IHC correlated well with both H-score (r = 0.94, P < 0.001) and percentage of positive cells (r = 0.89, P < 0.001) by conventional IHC. The PR stains showed similar results.
Conclusions: The QD-based multiplex, multispectral technique is able to reliably detect and measure multiple co-localized biomarkers in the same cellular compartment, such as nuclear ER and PR, on single paraffin embedded tissue sections. This technique can enhance our ability to assess breast tumor markers in specimens with limited available tissue, especially as complex image analysis is better developed.
Monday, February 28, 2011 1:00 PM
Poster Session II # 276, Monday Afternoon