Abstract 1548P
Background
The aim of this study was to investigate the prognostic significance of membranous β-catenin and cytoplasmic β-catenin expression in pancreatic cancer patients (pts).
Methods
One hundred pts, 53 males and 47 females with exocrine pancreatic ductal adenocarcinoma were retrospectively studied. All studied tumor samples were acquired from pancreatectomy specimens of primary tumors and not from biopsies or metastases. Resection with microscopic residual tumour (R1) was performed in 23 pts while in the 65 pts radical resection with microscopically negative margins (R0) was possible. The membranous β-catenin, cytoplasmic β-catenin and cell nucleus β-catenin expression were evaluated. An indirect immunohistochemistry using monoclonal mouse anti-human β-catenin-1 antibody was used. Immunohistochemistry was scored semiquantitavely.
Results
The expression of membranous β-catenin was <5% in no patient, 5-25% in one patient, 26-50% in 2 pts, 51-75% in 14 pts and >75% in 81 pts. The expression of cytoplasmic β-catenin was <5% in 34 pts, 5-25% in 42 pts, 26-50% in 18 pts, 51-75% in 3 pts and >75% in one patient. The expression of β-catenin in cell nucleus was negative in all pts. At the time of last follow-up update, 21 pts lived and 79 pts died. Median overall survival (OS) (95% CI) was 1.6 years (1.3-1.8). Median OS (95% CI) was 1.3 years (0.4-2.3) in pts with membranous β-catenin expression ≤ 75% and 1.7 years (1.3-2.1) in pts with membranous β-catenin expression >75% (p=0.045). Median OS (95% CI) was 2.2 years (1.8–2.5) in pts with cytoplasmic β-catenin expression <5%, 1.5 years (1.2-1.7) in pts with cytoplasmic β-catenin expression 5-25 % and 0.9 years (0.5-1.2) in pts with cytoplasmic β-catenin expression >25 % (p=0.024). In the univariate Cox proportional hazard models HR (95% CI) was 0.556 (0.311-0.995) in pts with membranous β-catenin expression >75% (p=0.048) and HR (95% CI) 2.200 (1.216-3.980) in pts with cytoplasmic β-catenin expression >25 % (p=0.009).
Conclusions
The present study provides data on favourable prognostic significance of membranous β-catenin expression and negative prognostic significance of cytoplasmic β-catenin expression in pancreatic cancer.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
MHCZ-DRO (TH, 0064190).
Funding
MHCZ-DRO (TH, 0064190) and Ministry of Defense of the Czech Republic - long-term organization development plan Medical Aspects of Weapons of Mass Destruction of the Faculty of Military Health Sciences, University of Defense.
Disclosure
All authors have declared no conflicts of interest.