Mo2020 Importance of Screening for Synchronous Malignant Neoplasms in Patients With Hepatocellular Carcinoma: Impact of FDG PET/CT

G A A b st ra ct s were classified as stage I/II (7th edition UICC TMN classification). From this group of 360 stage I/II HCCs, all cases with recurrent tumors, cancers with preoperative therapy, and combined hepatocellular cholangiocarcinoma were excluded, yielding a group of 106 HCCs that were further analyzed (I/II). Immunohistochemical analyses was performed on all EHM and stage I/II HCCs for the expression status of the stemness-related CK19 and key EMTrelated markers (vimentin, E-cadherin, and N-cadherin). Molecular results were compared with various clinicopathological features, followed by survival analysis in stage I/II HCCs. Results: CK19 was expressed in 56.5% (13/23) EHM and 18.9% (20/106) stage I/II HCCs (p=0.013). In EHM, CK19 expression was significantly associated with vimentin expression and loss of E-cadherin expression (CK19-positive vs. negative, 5/13 vs. 0/10; [p=0.027] for vimentin, and 5/13 vs 0/10 [p=0.027] for E-cadherin, respectively). These events were concurrently observed in 4/5 cases, suggesting the possibility of an EMT phenotype. In addition, in stage I/II HCCs, CK19-positive cases had shorter disease free survival (DFS) compared to CK19-negative cases (p=0.042). More specifically, 2-year DFS was significant, suggesting high incidence of intra-hepatic metastasis, and ruling out the existence of multicentric HCC.Multivariate analysis demonstrated that CK19-positivity was one of the independent prognostic factors for DFS after HCC resection (p=0.032, RR1.675 [95%CI; 1.0462.775] ). Conclusion: Our data highlight the CK19 staining is a promising biomarker for predicting synchronous or metachronous extra-hepatic metastasis in HCC patients, and is a significantly useful prognostic marker of early recurrence following surgery in stage I/II HCC patients.