Prognostic significance of CD44s expression in bile duct carcinomas

Abstract

14071 Background: CD44 is a surface glycoprotein and has a key role for surface hyaluronan receptor, which is associated with adhesion and metastasis in many solid tumors. There are CD44 standard isoform (CD44s) and ten variant isoforms (CD44v1–10). CD44s and CD44 variant 6 (CD44v6) were evaluated to clarify the applicable prognostic factor in patients with bile duct carcinomas. Methods: A retrospective study was performed in bile duct carcinomas. Immunohistochemical stain was done with primary antibodies for CD44 (Novocastra, Newcastle upon Tyne, UK) and CD44v6 (Novocastra) using automated machine (Vision Biosystems, Mount Waverley, VIC, Australia) and bond polymer detection system with counterstain (Vision Biosystems) in paraffin embedded tissues. The extent of staining categorized as 0% (none), <10% (weak), 10%-50% (moderate), and >50% (strong). Clinical characteristics including age, sex, stage, grade and overall survival were reviewed. Results: Ninety six patients (M:F=35:61) were evaluated and the median age of these patients was 64 years old (37∼86). The rate of overexpression (>10%) of CD44s was 50% and the rate of CD44v6 expression was 16.9%. With median 34.2 months of follow up, the overall survival of total 96 patients was 12.2 months. The Cox proportional hazards test identified CD44s overexpression. (HR:2.379, 95% CI:1.195–4.736, p=0.014) and the stage as prognostic factors. But the expression of CD44v6 (weak vs. moderate to strong, HR:3.983, 95%CI:0.295–1.588, p=0.377) showed no prognostic significance on overall survival. Conclusion: CD44s overexpression can be a poor prognostic marker in bile duct carcinomas. And there is a potential to apply postoperative investigational or aggressive therapy in this poor prognostic group. No significant financial relationships to disclose.