Clinicopathological features and originated model of postoperative recurrent hepatocellular carcinoma CONG Wen-ming, DONG Hui, WANG Bin, et al. Department of Pathology, Eastern Hepatobiliary Surgery Hospital，the Second Military Medical University，Shanghai 200438，China Corresponding author: CONG Wen-ming, E-mail: wmcong@smmu.edu.cn Abstract Objective To understanding the differences of clinicopathological features between primary hepatocellular carcinoma (P-HCC) and postoperative recurrent hepatocellular carcinoma (R-HCC), and their relationship with the clonal origins. Methods According to the difference of serum alpha-fetoprotein (AFP) levels between P-HCC and R-HCC, 106 paired cases of P-HCC and R-HCC were divided into Group A (n=29) with different serum AFP levels, Group B (n=77) with similar serum AFP levels, and three sub-patterns, TypeⅠ: single nodule within the same lobe; TypeⅡ: single nodule within the different lobe; Type Ⅲ: multiple nodules involved more than two lobes. The recurrent intervals, tumor size and histological types between A and B group were analyzed statistically. Results The mean time of intervals between Group A and Group B were 34.1±3.8 months and 24.6±2.7 months，respectively ( P <0.05); in which，TypeⅡ R-HCC in Group A were 39.4±5.9 months，significantly longer than that of 21.3 ± 4.1 months in Group B ( P <0.05); the mean size of R-HCC of TypeⅡin Group A and Group B were 4.6±1.3 cm and 6.4±0.9 cm, respectively ( P <0.05). There was no significant difference in tissue type, cell differentiation and growth mode. Conclusion About 25% of R-HCC has the features of multiple clonal origins, meaning new P-HCC, whereas about 75% of R-HCC could be highly considered as single clonal origin, meaning deriving from intrahepatic metastases. The analysis of recurrent patterns of R-HCC could provide useful information to evaluate their clonal origins.