Purpose: Keratin 19 (K19) is a known marker of poor prognosis and invasion in human hepatocellular carcinoma (HCC). However, the relationship between K19 and cancer stem cells (CSCs) is unclear. Here, we determined whether K19 can be used as a new CSC marker and therapeutic target in HCC.Experimental

Maximum tumor diameter, BMI, operator experience, and tumor location can be used to predict the operative time required to complete laparoscopic anterior resection with DST anastomosis for rectal cancer, with no correlations between pelvic dimensions and operative time. The difficulty of the procedure was not related to patients' pelvic dimensions, which led us to conclude that "narrow pelvis" is not a contraindication for this surgery. Based on these results, we suggest that laparoscopic anterior resection should be performed by experienced surgeons in patients with large tumors, high BMI, and/or extraperitoneal rectal cancer.

Objective: To evaluate the long-term outcomes of surgery for recurrent hepatocellular carcinoma (HCC). Background: HCC recurs with high incidence after liver resection. Little is known about long-term outcomes of patients undergoing surgery for recurrent HCC. Methods: Among 989 patients who underwent R0/R1 liver resection for HCC between 1995 and 2014, 676 patients who exhibited recurrence were included. Repeat surgery was performed in 128 patients (RS group), and not in the remaining 548 patients (NS group). Prognostic value after repeat surgery was evaluated by comparing survival after recurrence (SAR) between the RS and NS groups. Subgroup analyses according to the 3 recurrence patterns [intrahepatic recurrence (IHR), extrahepatic recurrence (EHR), and intra plus extrahepatic recurrence (IHR + EHR)] were performed. Results: Seventy-three of 430 patients (17.0%) with IHR, 17 of 57 patients (29.8%) with EHR, and 38 of 189 patients (20.1%) with IH + EHR underwent repeat surgery. Compared with the NS group, the RS group had better liver function and their time to recurrence was significantly longer (16.5 vs 11.4 months; P < 0.001). In the overall and 3 recurrence patterns, the 5-year SAR rate was better in the RS group compared with the NS group (RS vs NS group; overall, 53.0% vs 25.7%; IHR, 73.8% vs 37.2%; EHR, 30.0% vs 0%; IHR + EHR, 34.1% vs 10.6%; all P < 0.001, respectively). On multivariate analysis, repeat surgery was identified as an independent factor for better SAR (P < 0.001). Conclusion: Surgery for recurrent HCC may yield long-term survival for not only IHR but also for EHR in selected patients.

A whole-organ regeneration approach, using a decellularised xenogeneic liver as a scaffold for the construction of a transplantable liver was recently reported. Deriving suitable scaffolds was the first step towards clinical application; however, effective recellularisation remains to be achieved. This report presents a strategy for the improvement of the recellularisation process, using novel cell-seeding technique and cell source. We evaluated recellularised liver grafts repopulated through the portal vein or the biliary duct with mice adult hepatocytes or E14.5 foetal hepatocytes. More than 80% of the cells seeded through the biliary tree entered the parenchyma beyond the ductule-lining matrix barrier and distributed throughout the liver lobule. In contrast, about 20% of the cells seeded through the portal tree entered the parenchyma. The gene expression levels of foetal hepatocyte albumin, glucose 6-phosphatase, transferrin, cytokeratin 19, and gamma-glutamyl transpeptidase were increased in three-dimensional cultures in the native liver-derived scaffolds, and the activation of liver detoxification enzymes and formation of biliary duct-like structures were supported. The metabolic functions of liver grafts recellularised with different cell types were similar. These results suggest that biliary tree cell-seeding approach is promising, and that liver progenitor cells represent a good cell source candidate.

Tissue decellularization produces a three-dimensional scaffold that can be used to fabricate functional liver grafts following recellularization. Inappropriate cell distribution and clotting during blood perfusion hinder the practical use of recellularized livers. Here we aimed to establish a seeding method for the optimal distribution of parenchymal and endothelial cells, and to evaluate the effect of liver sinusoidal endothelial cells (LSECs) in the decellularized liver. Primary rat hepatocytes and LSECs were seeded into decellularized whole-liver scaffolds via the biliary duct and portal vein, respectively. Biliary duct seeding provided appropriate hepatocyte distribution into the parenchymal space, and portal vein-seeded LSECs simultaneously lined the portal lumen, thereby maintaining function and morphology. Hepatocytes co-seeded with LSECs retained their function compared with those seeded alone. Platelet deposition was significantly decreased and hepatocyte viability was maintained in the co-seeded group after extracorporeal blood perfusion. In conclusion, our seeding method provided optimal cell distribution into the parenchyma and vasculature according to the three-dimensional structure of the decellularized liver. LSECs maintained hepatic function, and supported hepatocyte viability under blood perfusion in the engineered liver graft owing to their antithrombogenicity. This recellularization procedure could help produce practical liver grafts with blood perfusion.

The current lack of cancer stem cell (CSC) markers that are easily evaluated by blood samples prevents the establishment of new therapeutic strategies in hepatocellular carcinoma (HCC). Herein, we examined whether sex determining region Y-box 9 (SOX9) represents a new CSC marker, and whether osteopontin (OPN) can be used as a surrogate marker of SOX9 in HCC. In HCC cell lines transfected with a SOX9 promoter-driven enhanced green fluorescence protein gene, FACS-isolated SOX9+ cells were capable of self-renewal and differentiation into SOX9− cells, and displayed high proliferation capacity in vitro. Xenotransplantation experiments revealed that SOX9+ cells reproduced, differentiated into SOX9− cells, and generated tumors at a high frequency in vivo. Moreover, SOX9+ cells were found to be involved in epithelial-mesenchymal transition (EMT) and activation of TGFb/Smad signaling. Gain/loss of function experiments showed that SOX9 regulates Wnt/beta-catenin signaling, including cyclin D1 and OPN. Immunohistochemistry of 166 HCC surgical specimens and serum OPN measurements showed that compared to SOX9− patients, SOX9+ patients had significantly poorer recurrence-free survival, stronger venous invasion, and higher serum OPN levels. In conclusion, SOX9 is a novel HCC-CSC marker regulating the Wnt/beta-catenin pathway and its downstream target, OPN. OPN is a useful surrogate marker of SOX9 in HCC.

Background The Brisbane 2000 Terminology for Liver Anatomy and Resections, based on Couinaud’s segments, did not address how to identify segmental borders and anatomic territories of less than one segment. Smaller anatomic resections including segmentectomies and subsegmentectomies, have not been well defined. The advent of minimally invasive liver resection has enhanced the possibilities of more precise resection due to a magnified view and reduced bleeding, and minimally invasive anatomic liver resection (MIALR) is becoming popular gradually. Therefore, there is a need for updating the Brisbane 2000 system, including anatomic segmentectomy or less. An online "Expert Consensus Meeting: Precision Anatomy for Minimally Invasive HBP Surgery (PAM‐HBP Surgery Consensus)" was hosted on February 23, 2021. Methods The Steering Committee invited 34 international experts from around the world. The Expert Committee (EC) selected 12 questions and two future research topics in the terminology session. The EC created seven tentative definitions and five recommendations based on the experts’ opinions and the literature review performed by the Research Committee. Two Delphi Rounds finalized those definitions and recommendations. Results This paper presents seven definitions and five recommendations regarding anatomic segmentectomy or less. In addition, two future research topics are discussed. Conclusions The PAM‐HBP Surgery Consensus has presented the Tokyo 2020 Terminology for Liver Anatomy and Resections. The terminology has added definitions of liver anatomy and resections that were not defined in the Brisbane 2000 system.

A preoperative prognostic model incorporating F-FDG-PET imaging with the ALBI grade may be useful for estimating the prognosis of selected patients with solitary HCC.