Lymph node metastasis (pN+, SBE-��-CD p < 0.0001, Hazard Ratio (HR) = 12.1940, 95% CI = 5.9509 - 24.9867), pT-category (pT3/4, p < 0.0001, HR = 3.8447, 95% CI = 1.5309 - 9.6553) and grading (G3/4, p < 0.0001, HR = 4.0652, 95% CI = 1.7123 - 9.6514) were shown to be unfavorable factors in univariate analysis in the whole population of all EACs (n = 60). Survival in subgroup with high LgR5 expression in BE (n = 41, p = 0.0278, HR = 3.5145, 95% CI = 1.5050 - 8.2073, Figure 4a), adjacent EACs (n = 41, p = 0.039, HR = 2.8408, 95% CI = 1.2496 - 6.4582) and all EACs (n = 60, p = 0.0325, HR = 2.4175, 95% CI = 1.1719 - 4.9872, Figure 4b) was significantly

poorer in comparison to the subgroup of patients with low expression of LgR5

(Table 1 and 2). Data suggest that LgR5 expression in BE and adjacent EACs is associated with clinical pathological Idasanutlin supplier features which may predict worse clinical outcome of related (adjacent) adenocarcinomas. Multivariate analysis using the Cox Proportional Hazards Model demonstrate lymph node metastasis and grading but not LgR5 expression as independent prognostic factors in all (n = 60) EACs (LN positive: Exp (b) 9.1861; 95% CI of Exp (b) 2.0665 – 40.8346; p = 0.003746. Grading G3/4: Exp (b) 2.2593; 95% CI of Exp (b) 1.0171 – 5.0186; p = 0.4643). Figure 4 Kaplan-Meier survival curves. Overall survival curves calculated by Kaplan-Meier Thalidomide method in Barrett-associated EACs (Figure 4a) and the whole population of all EACs (Figure 4b), respectively. Survival of patients with EAC was better when BE showed low LgR5 expression compared to high LgR5 expression. This was shown for BE in association with EAC (p = 0.0278) (a) and the whole population of EACs (b), respectively (p = 0.0325). The times of the censored data are indicated

by short vertical lines. Discussion Similar to other solid tumor entities [8], a stem cell hypothesis has been proposed for Barrett’s esophagus (BE) and its association with EAC [13]. However, this hypothesis has not undergone thorough investigation so far. An intestinal stem cell marker, LgR5 has been proposed [13], but have also not been thoroughly addressed in histogenetic studies. Our results of LgR5 expression in EAC with and without BE, as well as the adjacent Barrett mucosa suggest that LgR5 might be a promising marker to further address the stem cell hypothesis. In esophageal SCC – as expected no LgR5 expression was found, which is due to the fact that ESCC is not derived from an intestinal (glandular) type epithelium. Several studies have already focused on the Bcl-2 inhibitor effects of different LgR5 expression in the context of tumor development and progression.