Decreased CD10 Expression Is Associated with a Higher Risk of Relapse in Ductal Carcinoma In Situ (DCIS).

Abstract

Abstract Background: The Van Nuys Prognostic Index (VNPI) is the most widely used tool to predict local recurrence and guide therapy for DCIS. Nevertheless, many patients are still over-treated. Pre-clinical evidence indicates myo-epithelial cell (MEC) death in DCIS is a pre-requisite to tumor invasion. In this study we hypothesized that loss of CD10, (a marker of MECs), would be a surrogate for basement membrane disruption and tumor invasion. The aim of the present study was to retrospectively evaluate the prognostic value of CD10 in pure DCIS.Methods: CD10 expression was evaluated by qRT-PCR and immuno-histochemistry (IHC) using FFPE tissues on normal samples (N=11) and two independent pure DCIS populations: a training set (N=66) and a validation set (N=88).Results: MECs were the only cells that showed CD10 staining using IHC in normal and DCIS samples. All normal breast tissue samples demonstrated high expression levels of CD10 using both IHC and RT-PCR. In contrast, DCIS samples showed a wide range of CD10 expression levels: 1/3 of DCIS expressed high CD10 levels similar to those observed in normal breast tissue (high expression), whereas 2/3 expressed CD10 at a level below normal breast tissue (low expression). DCIS tumors with low CD10 mRNA levels were significantly associated with a higher risk of local relapse (HR= 2.49; [95%CI: 1.13-5.49], p=0.02). These results were validated in an independent dataset (HR= 1.805 [95%CI: 1.11-2.92], p=0.016). Of interest, no local relapses were observed in the high CD10 expression DCIS group. In multivariate analysis, CD10 expression by qRT-PCR was significantly associated with relapse (HR= 2.25, [95%CI: 1.24-4.09], p=0.008) in addition to VNPI score (HR: 2.03; [95%CI: 1.23-3.35], p=0.006).Conclusion: Decreased expression of CD10 in DCIS is associated with a higher risk of local relapse. These promising results are currently being validated in a larger patient series. Assessment of CD10 in addition to VPNI may lead to improved treatment tailoring for women with DCIS. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2112.