Fluorescence in situ hybridization detection of chromosome 7 and/or 17 polysomy as a prognostic marker for cholangiocarcinoma

Cholangiocarcinoma (CCA) is highly endemic in the Northeast Thailand. Recently, chromosome aberrations provided new insights into pathogenesis of CCA. Therefore, chromosome aberration might be used as a prognostic factor and therapeutic planning of this cancer. This aim of this study is to examine the correlation between an increase of chromosome 7 (C7) and/or 17 (C17) copy number variants (CNVs) with clinicopathological data and the overall survival time (OS) of CCA patients using fluorescence in situ hybridization (FISH) assays. C7 and C17 CNVs were examined using FISH form 157 formalin-fixed paraffin-embedded (FFPE) tissues of CCA patients from Khon Kaen, Thailand between 2011 and 2015. OS was visualized using Kaplan-Meier plot. Univariate and multivariate analyses were used to determine the ability of the clinicopathological parameters to predict OS. C17 > trisomy (odd ratio, 6.944, P < 0.001), C7/17 trisomy (odd ratio; 4.488, P = 0.019), and C7/17 > trisomy (odd ratio; 6.723, P < 0.001) were independently predictive factors for lymph node metastasis. Interestingly, an increase of C7, C17, and C7/17 CNVs in both trisomy and > trisomy was independently correlated with short median OS. An increased of C7 and/or 17 have a potential as a poor prognostic marker in CCA patients.