Endoglin expression in upper urinary tract urothelial carcinoma is associated with intravesical recurrence after radical nephroureterectomy

OBJECTIVES: To evaluate the expression and prognostic significance of endoglin in patients with upper urinary tract urothelial carcinoma. METHODS: zArchival formalin-fixed and paraffin-embedded tissues from 99 cases of primary upper urinary tract urothelial carcinomas treated with nephroureterectomy were retrieved. Tissue microarrays were constructed with triplicate tumor samples and paired non-neoplastic urothelium. Tissue microarrays were analyzed using immunohistochemistry for endoglin, and the associations between clinicopathological parameters and outcome were studied. RESULTS: Endoglin expression was significantly higher in the endothelium of upper urinary tract urothelial carcinomas than in paired benign urothelium (P < 0.001). Endoglin expression was not associated with pathological T stage or tumor grade, and it was not associated with increased hazard ratios for cancer-specific mortality, tumor recurrence in the lymph node or distant metastasis. However, expression of endoglin was significantly associated with intravesical recurrence, when adjusting for other relevant clinicopathological variables (P = 0.015). CONCLUSIONS: Endoglin is overexpressed in the endothelium of upper urinary tract urothelial carcinomas when compared with normal urothelium, and this overexpression seems to be associated with a higher risk of intravesical recurrence. Therefore, endoglin could be a biomarker for the prediction of intravesical recurrence, as well as a potential therapeutic target.