Genomic homogeneity in fibrolamellar carcinomas

Background-Fibrolamellar carcinoma (FLC) is a variant of hepatocellular car cinoma (HCC) with distinctive clinical and histological features. To date t here have been few studies on the genotypic aspects of FLC and no previous attempts have been made to use the arbitrarily primed-polymerase chain reac tion (AF-FCR) technique to detect genetic alterations in this disease. Aim-The aim of this study was to assess the degree of genomic heterogeneity of FEC using the AP-PCR technique. Methods-A fetal of 50 tissue samples of primary and metastatic FLCs from seven patients were microdissected. AP-PC R amplification of each genomic DNA sample was carried out using two arbitr ary primers. Results-DNA fingerprints of the primary FLCs and all their metastatic lesio ns (both synchronous and metachronous disease) were identical in an individ ual patient. The fingerprints were different between tumours of different p atients. No evidence of intratumour heterogeneity was observed. Conclusions-Such genomic homogeneity in FLCs may explain their indolent gro wth. The absence of clonal evolution, which is present in other tumours (pa rticularly HCCs), may explain the distinct behaviour in this tumour. The tu morigenic pathway and degree of somatic genomic changes in this disease may be less complex than in HCC.