Abstract P1-06-03: Microvessel density as determined by computerized image analysis of CD34 and CD105 expression correlates with poor outcome in triple-negative breast cancer

Abstract

Abstract Background: Triple-negative and basal-like breast cancers tend to relapse and metastasize early with a peculiar pattern of dissemination. Occurrence of metastasis is related to angiogenesis, yet literature on angiogenic characteristics of these tumors is limited. We examined blood vessels topography and microvessel density (MVD) in triple-negative breast cancer (TNC), investigating their association with clinicopathological criteria, basal phenotype and prognosis. Methods: For identification of blood vessels, FFPE whole tissue sections were stained with CD34 and CD105. Slides were scanned using ScanScope, Aperio Digital Pathology System. Subsequently, digital slides were analyzed with Aperio ImageScope, Microvascular Density v1 algorithm. Total MVD and MVD in three areas (intratumoral, IT, peripheral tumoral, PP and peritumoral, PT) were assessed as described by Weidner et al and correlated with prognosis. Results: A total of 48/133 pts (36.1%) were younger than 50 years (mean 55 yrs; range 32–86 yrs) and 41 (30.8%) were premenopausal women. The majority of TNCs were invasive ductal carcinomas NST (106/133); 80 (60.2%) cases were lymph node positive and 101 (75.9%) were found to have a basal-like phenotype. LVI was identified in 64/133 (48.1%) tumors. Median follow-up was 40 mos (range 1–161 mos). Overall, 53 (39.1%) patients had developed a recurrence by the time of the last follow-up, 49 (36.8%) had developed distant metastasis and 45 (33.8%) had died from breast cancer. Blood vessels were located largely in the peripheral tumoral area. Tumors with high total CD34 MVD, CD34 MVD at the peripheral area (PP-MVD) and CD34 MVD at the peritumoral area (PT-MVD) were significantly associated with the development of visceral metastasis (p = 0.006; p = 0.013; p = 0.019). Also, high CD34 PT-MVD was associated with recurrence (p = 0.010), advanced tumoral stage (p = 0.028) and lymph node (LN) metastasis (p = 0.048). While high total CD105 MVD and CD105 PP-MVD were associated with distant metastasis (p = 0.048; p = 0.031), CD105 PT-MVD was correlated with vascular invasion (p = 0.015). Moreover, CD105 PP-MVD was strongly associated with poorer overall survival (OS; p = 0.001) and disease-free interval (DFI; p = 0.001). Interestingly, TNCs with a basal phenotype showed higher CD34 PT-MVD and CD105 PT-MVD (p = 0.017; p = 0.046). In multivariate analysis for OS, total CD34 MVD (RR = 2.20; 95% CI 1.11–4.35; p = 0.023) and CD105 PP-MVD (OS: RR = 2.78; 95% CI 1.41–5.49; p = 0.003) retained significance after adjustment for stage, LN status and distant metastasis. As for DFI, CD34 PT-MVD (RR = 1.99; 95% CI 1.03–3.87; p = 0.040) and CD105 PP-MVD (RR = 2.90; 95% CI 1.54–5.48; p = 0.001) showed statistical significance after adjustment for the same variables. Conclusions: Our findings demonstrate significant associations between MVD in different tumoral areas and various parameters in triple-negative breast tumors, indicating that TNCs with aggressive features have higher MVDs. Furthermore, peripheral tumoral CD105 MVD is a strong, independent prognostic factor in TNC. Finally, blood vessels are mainly located in the peripheral area of TNCs and seem to have a critical role in tumor progression by representing means for disease dissemination. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-06-03.