Gene expression profiling of peripheral blood cells for early detection of breast cancer

Purpose: Early detection of breast cancer is key to successful treatment and patient survival. We have previously reported the potential use of gene expression profiling of peripheral blood cells for early detection of breast cancer. The aim of the present study was to validate these findings using a larger sample size and a commercially available microarray platform. Experimental Design: Blood samples were collected from 121 females referred for diagnostic mammography following an initial suspicious screening mammogram. Diagnostic work-up revealed that 67 of these women had breast cancer while 54 had no malignant disease. Additionally, 9 samples from 6 healthy female controls (three pregnant women, one breast-feeding woman and two healthy controls at different timepoints in their menstrual cycle) were included. Gene expression analyses were conducted using high-density oligonucleotide microarrays. Partial Least Square Regression was used for model building and predictors were identified using a Jackknifing approach. Prediction performance was determined by a 20-fold double cross validation approach