Comparison of clinical outcome between laparoscopic and open hepatectomy of high difficulty score for hepatocellular carcinoma: a propensity score analysis.

BACKGROUND: Laparoscopic liver resection (LLR) of high difficulty score is technically challenging. There is a lack of clinical evidence to support its applicability in terms of the long-term survival benefits. This study aims to compare clinical outcomes between LLR and the open liver resection of high difficulty score for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: From 2010 to 2020, using Iwate criteria, 424 patients underwent liver resection of high difficulty score by the laparoscopic (n = 65) or open (n = 359) approach. Propensity score (PS) matching was performed between the two groups. Short-term and long-term outcomes were compared between PS-matched groups. Univariate and multivariate analyses were performed to identify prognostic factors affecting survival. RESULTS: The laparoscopic group had significantly fewer severe complications (3% vs. 10.8%), and shorter median hospital stays (6 days vs. 8 days) than the open group. Meanwhile, the long-term oncological outcomes were comparable between the two groups, in terms of the tumor recurrence rate (40% vs. 46.1%), the 5-year overall survival rate (75.4% vs. 76.2%), and the 5-year recurrence-free survival rate (50.3% vs. 53.5%). The high preoperative serum alpha-fetoprotein level, multiple tumors, and severe postoperative complications were the independent poor prognostic factors associated with worse overall survival. The surgical approach (Laparoscopic vs. Open) did not influence the survival. CONCLUSION: LLR of high difficulty score for selected patients with HCC has better short-term outcomes than the open approach. More importantly, it can achieve similar long-term survival outcomes as the open approach.

Is hepatic resection justified for non-colorectal non-neuroendocrine liver metastases? A systematic review and meta-analysis.

BACKGROUND: Hepatic resection (HR) is effective for colorectal or neuroendocrine liver metastases. However, the role of HR for non-colorectal non-neuroendocrine liver metastases (NCNNLM) is unknown. This study aims to perform a systematic review and meta-analysis on long-term clinical outcomes after HR for NCNNLM. METHODS: electronic search was performed to identify relevant publications using PRISMA and MOOSE guidelines. Primary outcomes were 3- and 5-year overall survival (OS) and disease-free survival (DFS). Secondary outcomes were post-operative morbidity and 30-day mortality. RESULTS: There were 40 selected studies involving 5696 patients with NCNNLM undergone HR. Pooled data analyses showed that the 3- and 5-year OS were 40% (95% CI 0.35-0.46) and 32% (95% CI 0.29-0.36), whereas the 3- and 5-year DFS were 28% (95% CI 0.21-0.36) and 24% (95% CI 0.20-0.30), respectively. The postoperative morbidity rate was 28%, while the 30-day mortality was 2%. Subgroup analysis on HR for gastric cancer liver metastasis revealed the 3-year and 5-year OS of 39% and 25%, respectively. CONCLUSIONS: HR for NCNNLM may achieve satisfactory survival outcome in selected patients with low morbidities and mortalities. However, more concrete evidence from prospective study is warrant in future.

The Impact of Involved Resection Margin on Recurrence and Survival After Pancreaticoduodenectomy for Periampullary Carcinoma, with Emphasis on Pancreatic Head Carcinoma.

BACKGROUND: The supposed adverse effect of involved resection margin during pancreaticoduodenectomy (PD) for periampullary carcinoma or pancreatic head carcinoma (CaP) on long-term oncological outcomes is still inconclusive. METHODS: This is a retrospective study on periampullary carcinoma undergoing PD. Patients with R0 (margin clear) resection were compared to patients with R1 (microscopically directly involved margin) resection. Patients with gross involved margin (R2 resection) were excluded. Long-term oncological outcomes measured included incidence and site of recurrent disease, overall survival (OS) and disease-free survival (DFS). A subgroup analysis was made on patients with CaP. RESULTS: Between January 2003 and December 2019, 203 PD were identified for present study. The incidence of R1 resection was common (12% in periampullary carcinoma and 20% in CaP). In periampullary carcinoma, R1 resection had greater proportion of CaP, lesser proportion of carcinoma of ampulla (CaA), more perineural invasion, more lymph node (LN) metastasis. R1 group had a shorter OS and DFS, but no difference in the incidence and site of recurrent disease. In the subgroup of CaP (91 patients), R1 group did not differ from R0 group except for more LN metastasis. There was no difference in incidence and site of recurrent disease, OS and DFS. On multivariable analysis, R1 resection was not an independent factor for OS and DFS for periampullary carcinoma or for CaP only. CONCLUSION: Involved resection margin was not uncommon. It was not associated with higher incidence of recurrent disease including local recurrence, and was not an independent prognosticator for OS and DFS.

Novel use of the falciform ligament for reconstruction of the inferior vena cava and its tributary.

Tumor invasion into the inferior vena cava (IVC) and hepatic vein (HV) is challenging in cancer surgery with curative intent. Appropriate techniques for venous reconstruction are essential. We have described in detail a novel technique of fashioning an interposition tube graft using the falciform ligament to reconstruct the IVC and HV. The falciform ligament maintains all the benefits of an autologous tissue graft, with the added advantage of its flexibility in customizing graft dimensions. Its use in IVC and HV reconstruction has rarely been reported. The short-term outcomes with this tube graft are promising.

Liver development, regeneration, and carcinogenesis.

The identification of putative liver stem cells has brought closer the previously separate fields of liver development, regeneration, and carcinogenesis. Significant overlaps in the regulation of these processes are now being described. For example, studies in embryonic liver development have already provided the basis for directed differentiation of human embryonic stem cells and induced pluripotent stem cells into hepatocyte-like cells. As a result, the understanding of the cell biology of proliferation and differentiation in the liver has been improved. This knowledge can be used to improve the function of hepatocyte-like cells for drug testing, bioartificial livers, and transplantation. In parallel, the mechanisms regulating cancer cell biology are now clearer, providing fertile soil for novel therapeutic approaches. Recognition of the relationships between development, regeneration, and carcinogenesis, and the increasing evidence for the role of stem cells in all of these areas, has sparked fresh enthusiasm in understanding the underlying molecular mechanisms and has led to new targeted therapies for liver cirrhosis and primary liver cancers.

Stem cells and liver repair.

The liver has considerable inherent regenerative capacity through hepatocyte division and hepatic progenitor cell proliferation. In chronic disease regeneration eventually fails and liver transplantation is the only curative treatment. Current work aims to restore liver mass and functionality either through transplantation of stem cell derived hepatocyte-like cells or by stimulating endogenous liver repair. Human embryonic stem cells (ESCs) and adult somatic cells can be differentiated into hepatocyte-like cells with potential use in drug testing, bio-artificial livers and transplantation. These cells still have some limitations in functionality, understanding further human liver development and improving tissue culture is required. The use of stem cells and their progeny in animal models of liver disease has been encouraging and stimulated clinical trials to commence.