Urokinase-type plasminogen activator gene (PLAU) to predict clinical outcome in invasive lobular carcinoma.

e21010 Background: At the molecular level invasive lobular carcinoma (ILC) is mostly composed of luminal A (LA) (≈80%) followed by luminal B (≈15%) and a small fraction of HER2-positive (≈5%) tumors (Metzger et al SABCS2011). In ILC, Genomic Grade (GG) adds prognostic information to clinico-pathological (CP) characteristics (Metzger et al ASCO 2011). In this study we sought to evaluate the prognostic value of different gene signatures/modules in patients diagnosed with LA classic ILC. Methods: Gene expression data were generated from 184 consecutive frozen tumor samples using Affymetrix U133 Plus 2.0 arrays. ILC tumors were classified into molecular subtypes using the PAM50 classifier. ILC tumors characterized as classic ILC by pahtologists and as LA by PAM50 were selected for this analysis. Invasive disease free survival (IDFS) was defined as the interval between date of surgery and date of any invasive recurrence or death. Multivariate analyses for IDFS and overall survival (OS) adjusted for age, tumor ...