Automated Quantitative Proteomic Analysis Platform (HISTORX): Clinical Application and Comparison with Routine Immunohistochmeistry among Diffuse Large B-Cell Lymphoma (DLBCL) Patients (Pts)
A Klimowicz, N Bahlis, A Magliocco, D Demetrick, L Difrancesco, D Stewart, A Mansoor. Tom Baker Cancer Ctr., Calgary, AB, Canada; University of Calgary/CLS, Calgary, AB, Canada
Background: DLBCL is a heterogeneous & aggressive disease with unpredictable clinical course. Biological markers like GCB vs. ACB phenotype; bcl2 / p53 has been evaluated by immunoperoxidase (IPOX) staining; but with inconclusive results. Quantifying protein expression (Ki-67; p53; ER/PR), by IPOX is observer dependent and semi-quantitative. The AQUA automated quantitative pathology system (HISTORX) is proteomic analysis platform. It quantitates absolute number of protein molecules within discrete sub cellular locations by combining fluorescence-based image analysis with automated microscopy. This pilot study evaluated the clinical applicability of HistoRX in comparison with routine IPOX by correlating these scores with Overall survival in DLBCL pts.
Design: Triplicate (0.6-mm) cores from FFPE tissue at diagnosis (2001-04) were used for tissue microarray (TMA). TMA sections were stained with CD20, CD3 & Ki-67 antibodies using standard protocol (Ventana -AZ). Visual estimation of IPOX staining was recorded in 10% increments (>50% was considered as high Ki-67). TMA sections stained with anti-Ki-67 (MIB1-Dako1:200) were used for Fluorescent immunohistochemistry. Automated image acquisition was performed by the HistoRx PM-2000 and analyzed by AQUA script. Mean AQUA scores (nuclear compartment) separated pts into the binomial variables of high (>50%) and low positive, using hierarchical clustering analysis (Ward's method). Fisher's exact test, Kaplan-Meier / Mann-Whitney non-parametric tests were used for statistical analysis.
Results: 56 pts (35M/21F); median age 66 yrs (range 34-86) were included. 21/56 (38%) had stage I/II and (62%) had stage III/IV. Pts were treated with CHOP (41%) or RCHOP (59%) regimens; median follow-up was 22M. By HistoRX, OS was favorable among pts with high Ki-67 (86% vs. 67%; p = 0.056) . High Ki67 has significant predictive value among CHOP group (88% vs. 46%; p = 0.034) compared to RCHOP (88% vs. 86%; p = 0.737). High Ki-67 staining by IPOX did not show any association with OS in all (79% vs.75%, p = 0.928) or among pts treated with CHOP (58% vs. 63%, p = 0.518) or RCHOP (88% vs. 82; p = 0.320).
Conclusions: HISTORX provides superior quantification of proteins in tissues compared to routine IPOX and further studies are required to evaluate clinical applicability of this novel technique.
Category: Special Category for 2009 - Pan-genomic/Pan-proteomic approaches to Cancer
Tuesday, March 10, 2009 9:30 AM
Poster Session III # 225, Tuesday Morning