Clinical practice guidelines for hepatocellular carcinoma: The Japan Society of Hepatology 2017 (4th JSH-HCC guidelines) 2019 update

The fourth version of Clinical Practice Guidelines for Hepatocellular Carcinoma was revised by the Japan Society of Hepatology, according to the methodology of evidence-based medicine and partly to the Grading of Recommendations Assessment, Development, and Evaluation system, which was published in October 2017 in Japanese. New or revised recommendations were described, herein, with a special reference to the surveillance, diagnostic, and treatment algorithms.

Surgical treatment of hepatocellular carcinoma associated with hepatic vein tumor thrombosis

BACKGROUND & AIMS

Presence of hepatic vein tumor thrombosis (HVTT) in patients with hepatocellular carcinoma (HCC) is regarded as signaling an extremely poor prognosis. However, little is known about the prognostic impact of surgical treatment for HVTT.

METHODS

Our database of surgical resection for HCC between October 1994 and December 2011 in a tertiary care Japanese hospital was retrospectively analysed. We statistically compared the patient characteristics and surgical outcomes in HCC patients with tumor thrombosis in a peripheral hepatic vein, including microscopic invasion (pHVTT), tumor thrombosis in a major hepatic vein (mHVTT), and tumor thrombosis of the inferior vena cava (IVCTT). Among 1525 hepatic resections, 153 cases of pHVTT, 21 cases of mHVTT, and 13 cases of IVCTT were identified.

RESULTS

The median survival time (MST) in the pHVTT and mHVTT groups was 5.27 and 3.95 years, respectively (p=0.77), and the median time to recurrence (TTR) was 1.06 and 0.41 years, respectively (p=0.74). On the other hand, the MST and TTR in the patient group with IVCTT were 1.39 years and 0.25 year respectively; furthermore, the MST of Child-Pugh class B patients was significantly worse (2.39 vs. 0.44 years, p=0.0001). Multivariate analyses revealed IVCTT (risk ratio [RR] 2.54, p=0.024) and R 1/2 resection (RR 2.08, p=0.017) as risk factors for the overall survival.

CONCLUSIONS

Hepatic resection provided acceptable outcomes in HCC patients with mHVTT or pHVTT when R0 resection was feasible. Resection of HCC may be attempted even in patients with IVCTT, in the presence of good liver function.

Clinical Practice Guidelines for Hepatocellular Carcinoma: The Japan Society of Hepatology 2021 version (5th JSH-HCC Guidelines)

The fifth version of the Clinical Practice Guidelines for Hepatocellular Carcinoma was revised by the Japan Society of Hepatology, according to the methodology of evidence-based medicine and partly to the Grading of Recommendations Assessment, Development and Evaluation system, which was published in October 2021 in Japanese. In addition to surveillance-diagnostic and treatment algorithms, a new algorithm for systemic therapy has been created, as multiple drugs for hepatocellular carcinoma can be currently selected. Here, new or revised algorithms and evidence on which the recommendations are based are described.

Long-term outcomes after surgical resection for gastric cancer liver metastasis: an analysis of 64 macroscopically complete resections

PURPOSE

The indication for hepatectomy in cases of gastric cancer liver metastases (GLM) remains unclear and it remains controversial whether surgical resection is beneficial for GLM. The objective of this retrospective study was to clarify the indications for and benefit of hepatectomy for GLM.

METHODS

Seventy-three patients underwent hepatectomies for GLM from January 1993 to January 2011. Macroscopically complete (R0 or R1) resection was achieved in 64 patients. Among them, 32 patients underwent synchronous hepatectomy with gastrectomy and the remaining 32 patients underwent metachronous hepatectomy. Repeat hepatectomy was done in 14 patients for resectable intrahepatic recurrences. Clinicopathological factors were evaluated by univariate and multivariate analyses among patients who received macroscopically complete resection for those affecting survival.

RESULTS

The overall 1-, 3-, and 5-year survival rates after macroscopically complete (R0 or R1) liver resection (n = 64) for GLM were 84, 50, and 37 %, respectively, with a median survival of 34 months. Univariate analysis identified serosal invasion of the primary gastric cancer and blood transfusions during surgery as poor prognosis indicators. By multivariate analysis, serosal invasion of the primary gastric cancer and larger hepatic tumor (>5 cm in diameter) were found to be independent indicators of poor prognosis.

CONCLUSIONS

GLM patients with the maximum diameter of hepatic tumors of <5 cm and without serosal invasion of the primary gastric cancer are the best candidate for hepatectomy.

Hepatic Stellate Cells in Hepatocellular Carcinoma Promote Tumor Growth Via Growth Differentiation Factor 15 Production

BACKGROUND & AIMS

Although the tumor microenvironment plays an important role in tumor growth, it is not fully understood what role hepatic stellate cells (HSCs) play in the hepatocellular carcinoma (HCC) microenvironment.

METHODS

A high-fat diet after streptozotocin was administered to HSC-specific Atg7-deficient (GFAP-Atg7 knockout [KO]) or growth differentiation factor 15 (GDF15)-deficient (GFAP-GDF15KO) mice. LX-2 cells, a human HSC cell line, were cultured with human hepatoma cells.

RESULTS

In the steatohepatitis-based tumorigenesis model, GFAP-Atg7KO mice formed fewer and smaller liver tumors than their wild-type littermates. Mixed culture of LX-2 cells and hepatoma cells promoted LX-2 cell autophagy and hepatoma cell proliferation, which were attenuated by Atg7 KO in LX-2 cells. Hepatoma cell xenograft tumors grew rapidly in the presence of LX-2 cells, but Atg7 KO in LX-2 cells abolished this growth. RNA-sequencing revealed that LX-2 cells cultured with HepG2 cells highly expressed GDF15, which was abolished by Atg7 KO in LX-2 cells. GDF15 KO LX-2 cells did not show a growth-promoting effect on hepatoma cells either in vitro or in the xenograft model. GDF15 deficiency in HSCs reduced liver tumor size caused by the steatohepatitis-based tumorigenesis model. GDF15 was highly expressed and GDF15-positive nonparenchymal cells were more abundant in human HCC compared with noncancerous parts. Single-cell RNA sequencing showed that GDF15-positive rates in HSCs were higher in HCC than in background liver. Serum GDF15 levels were high in HCC patients and increased with tumor progression.

CONCLUSIONS

In the HCC microenvironment, an increase of HSCs that produces GDF15 in an autophagy-dependent manner may be involved in tumor progression.

Application of fluorescent cholangiography to single-incision laparoscopic cholecystectomy

BACKGROUND

Although the use of single-incision laparoscopic cholecystectomy (SILC) is spreading rapidly, this technique has disadvantages. It does not allow for sufficient surgical views to be obtained or for intraoperative radiographic cholangiography to be performed. Fluorescent cholangiography using a preoperative intravenous injection of indocyanine green (ICG) may be useful for identifying the biliary tract during both SILC and conventional laparoscopic cholecystectomy.

METHODS

For seven patients undergoing SILC, 1 ml of ICG (2.5 mg) was administered by intravenous injection before the surgery. The prototype fluorescent imaging system consisted of a xenon light source and a 30° laparoscope (diameter, 10 mm) equipped with a charge-coupled device camera capable of filtering out light with wavelengths shorter than 810 nm. The laparoscope was introduced through an umbilical trocar. Fluorescent cholangiography then was performed by changing the color images to fluorescent images using a foot switch during dissection of the triangle of Calot.

RESULTS

Fluorescent cholangiography identified the confluence between the cystic duct and the common hepatic duct in all seven patients before and throughout the dissection of the triangle of Calot. The interval from the injection of ICG to the first obtained fluorescent cholangiography before dissection of the triangle of Calot ranged from 35 to 75 min.

CONCLUSIONS

Fluorescent cholangiography enabled real-time identification of the extrahepatic bile ducts during SILC without necessitating catheterization of the bile duct. Such properties of fluorescent cholangiography are expected to be helpful for ensuring the safety of SILC and expanding the indications for the procedure.

Efficacy of Preoperative Portal Vein Embolization Among Patients with Hepatocellular Carcinoma, Biliary Tract Cancer, and Colorectal Liver Metastases: A Comparative Study Based on Single-Center Experience of 319 Cases

BACKGROUND

Efficacy of preoperative portal vein embolization (PVE) has been established; however, differences of outcomes among diseases, including hepatocellular carcinoma (HCC), biliary tract cancer (BTC), and colorectal liver metastases (CLM), are unclear.

METHODS

Subjects included patients in a prospectively collected database undergoing PVE (from 1995 to 2013). A future liver remnant (FLR) volume ≥40% is the minimal requirement for patients with an indocyanine green retention rate at 15 min (ICGR15) <10%, and stricter criteria (FLR volume ≥50%) have been applied for patients with 20% > ICGR15 ≥ 10%. Patient characteristics and survivals were compared among those three diseases, and predictors of dropout and better FLR hypertrophy were determined.

RESULTS

In 319 consecutive patients undergoing PVE for HCC (n = 70), BTC (n = 172), and CLM (n = 77), the degree of hypertrophy did not significantly differ by cancer types (median 10, 9.6, and 10%, respectively). Eighty percent (256 of 319) of patients completed subsequent hepatectomy after a median waiting interval of 24 days (range 5-90), while dropout after PVE was more common in BTC or CLM (odds ratio 2.75, p = 0.018), mainly because of disease progression. Ninety-day liver-related mortality after hepatectomy was 0% in the entire cohort, and 5-year overall survival of patients with HCC, BTC, and CLM was 56, 50, and 51%, respectively (p = 0.948). No patients who dropped out survived more than 2.5 years after PVE.

CONCLUSION

PVE produced equivalent FLR hypertrophy among the three diseases as long as liver function was fulfilling the preset criteria; however, the completion rate of subsequent hepatectomy was highest in HCC. PVE followed by hepatectomy was a safe and feasible strategy for otherwise unresectable disease irrespective of cancer types.

The history of liver surgery: Achievements over the past 50 years

We reviewed the progress made in the field of liver surgery over the past 50 years. The widespread use and improved outcomes of the hepatectomy were, primarily, due to pioneer surgeons who were responsible for technological advances and rapid improvements in the safety of the procedure in the last century. These advances included the hepatic functional evaluation used to determine the safety limit of liver resections, the introduction of intraoperative ultrasonography, and the development of innovative techniques such as portal vein embolization to increase the remnant liver volume. Cadaveric liver transplantation has been attempted since 1963. However, the clinical outcomes only began improving and becoming acceptable in the 1970s-1980s due to refinements in technology and the development of new immunosuppressants. Partial liver transplantation from living donors, which was first attempted in 1988, required further technological innovation and sophisticated perioperative management plans. Moreover, these developments allowed for further overall improvements to take place in the field of liver surgery. Since the turn of the century, advances in computation and imaging technology have made it possible for safer and more elaborate surgeries to be performed. In Japan, preoperative 3-dimensional simulation technology has been covered by health insurance since 2012 and is now widely used. An urgent need for real-time navigation tools will develop in the future. Indocyanine green (ICG) fluorescence imaging was first used in 2007 and has led to the creation of a new surgical concept known as fluorescence navigation surgery. Laparoscopic surgery and robotic surgery have solved the issue of large incisions, which used to be a major drawback of open liver surgery; however, further improvements are required in order to achieve the level of safety and accuracy observed during open liver resection when performing all minimally invasive procedures. In the near future, liver surgery will become more precise and less invasive due to substantial progress including the development of navigation surgery, cancer imaging, and minimally invasive surgery. This overview of the history of liver surgery over the past 50 years may provide useful insights for further innovation in the next 50 years.

Profiling of tumour-associated microbiota in human hepatocellular carcinoma

Liver cancer is the fourth leading cause of cancer-related death. Hepatocellular carcinoma (HCC) is a primary liver cancer that results from chronic hepatitis caused by multiple predisposing factors such as viral infection, alcohol consumption, and non-alcoholic fatty liver disease. Accumulating studies have indicated that dysfunction of the gut epithelial barrier and hepatic translocation of gut microbes may be implicated in the pathogenesis of HCC. However, the translocated bacteria in HCC patients remains unclear. Here, we characterised tumour-associated microbiota in patients with liver cancer and focused on HCC. We observed that the number of amplicon sequence variants in tumour-associated microbiota was significantly higher compared with that in non-tumour regions of the liver. The tumour-associated microbiota consisted of Bacteroidetes, Firmicutes, and Proteobacteria as the dominant phyla. We identified an unclassified genus that belonged to the Bacteroides, Romboutsia, uncultured bacterium of Lachnospiraceae as a signature taxon for primary liver cancer. Additionally, we identified Ruminococcus gnavus as a signature taxon for HCC patients infected with hepatitis B and/or hepatitis C viruses. This study suggests that tumour microbiota may contribute to the pathology of HCC.

Distal Pancreatectomy with En Bloc Resection of the Celiac Axis with Preservation or Reconstruction of the Left Gastric Artery in Patients with Pancreatic Body Cancer

BACKGROUND

A distal pancreatectomy with en bloc celiac axis resection (DP-CAR) is indicated for left-sided locally advanced pancreatic ductal adenocarcinoma. However, ischemic complication resulting from the sacrifice of the common hepatic artery and left gastric artery (LGA) remain problematic. The aim of this study was to analyze the feasibility of DP-CAR with preservation or reconstruction of the left gastric artery.

METHOD

Between April 2011 and December 2014, we treated 17 cases using DP-CAR with preservation or reconstruction of the LGA. If the tumor had involved the LGA, the LGA was dissected and reconstructed using the middle colic artery. We retrospectively analyzed the feasibility of this procedure.

RESULTS

Among 17 consecutive patients who underwent DP-CAR, the LGA was preserved in 13 patients and reconstructed in four patients. Major postoperative complications were observed in seven cases (41 %). A pancreatic fistula (grade B/C) or delayed gastric emptying (grade B/C) occurred in 7 (41 %) and 2 (12 %) cases, respectively. The overall R0 resection rate was 94 % (16/17). Eleven cases developed recurrences (liver, n = 4; lymph nodes, n = 2; peritoneal dissemination, n = 2; lung, n = 2; local recurrence, n = 1). The overall 1- and 3-year postoperative survival rates were 74 and 45 %, respectively.

CONCLUSIONS

Our preliminary data showed that DP-CAR with preservation or reconstruction of the LGA is a safe and feasible approach, and that this procedure may reduce the risk of ischemic complications.

Role of surgical resection for non-colorectal non-neuroendocrine liver metastases

It is widely accepted that the indications for hepatectomy in colorectal cancer liver metastases and liver metastases of neuro-endocrine tumors result in relatively better prognoses, whereas, the indications and prognoses of hepatectomy for non-colorectal non-neuroendocrine liver metastases (NCNNLM) remain controversial owing to the limited number of cases and the heterogeneity of the primary diseases. There have been many publications on NCNNLM; however, its background heterogeneity makes it difficult to reach a specific conclusion. This heterogeneous disease group should be discussed in the order from its general to specific aspect. The present review paper describes the general prognosis and risk factors associated with NCNNLM while specifically focusing on the liver metastases of each primary disease. A multidisciplinary approach that takes into consideration appropriate timing for hepatectomy combined with chemotherapy may prolong survival and/or contribute to the improvement of the quality of life while giving respite from systemic chemotherapy.

Liver transplantation using hepatitis B core antibody-positive grafts: review and university of Tokyo experience

Hepatitis B surface antigen-negative and hepatitis B core antibody-positive grafts were considered unsuitable for transplantation. The number of potential recipients for liver transplantation now exceeds that of potential donor organs, which has led us to reevaluate the feasibility of these grafts. Several strategies involving prophylactic administration of hepatitis B immunoglobulin and/or lamivudine to transplant recipients have been proposed. At the University of Tokyo, we have continued to use hepatitis B immunoglobulin monoprophylaxis with zero recurrence. In this article we report our experience with the use of hepatitis B surface antigen-negative/hepatitis B core antibody-positive grafts with hepatitis B immunoglobulin monotherapy. We conducted a review of the literature regarding the feasibility of these grafts to reconfirm optimal prophylactic strategies for preventing de novo hepatitis B virus infection in transplant recipients.

Surgical resection of peritoneal or thoracoabdominal wall implants from hepatocellular carcinoma

BACKGROUND

Peritoneal or thoracoabdominal wall implants from hepatocellular carcinoma (HCC) occur occasionally after biopsy, percutaneous therapy or resection, and spontaneously, with no effective treatment available. The objective of this study was to clarify the indications for, and benefits of, surgical resection of such HCC implants.

METHODS

This was a retrospective analysis of patients who underwent resection for peritoneal or chest wall implants from HCC over 14 years (1997-2011). Indications for surgery for implanted HCC were: limited number of implanted lesions including those found incidentally during surgery; intrahepatic lesion absent or predicted to be locally controllable; and absence of ascites with sufficient hepatic functional reserve. Prognostic factors affecting survival after resection were determined by univariable and multivariable analysis.

RESULTS

A total of 32 patients underwent 36 resections. Cumulative 1-, 3- and 5-year overall survival rates were 71, 44 and 39 per cent respectively, with a median survival time of 34.5 months. Univariable and multivariable analysis revealed that poor perioperative intrahepatic disease control was associated with poor survival.

CONCLUSION

Surgical resection of implanted HCC may improve long-term survival in selected patients as long as intrahepatic disease is absent or well controlled.

New hepatic vein reconstruction in left liver graft

The incidence of hepatic venous stenosis is higher in partial liver transplantation. New methods for hepatic venous reconstruction in left liver transplantation, which secure wide anastomosis, were devised and are reported here. In the graft, the right side of the middle hepatic vein or the left side of the left hepatic vein was cut longitudinally and a rectangular-shaped vein patch was attached for venoplasty. In the recipient, after the left and middle hepatic veins were joined, the right side of the middle hepatic vein was cut toward the closed right hepatic vein, making a horizontal cavotomy for anastomosis. Of 92 patients who underwent conventional hepatic vein reconstruction, 3 were complicated by hepatic venous stenosis (median follow-up 43 months). By contrast, there were no hepatic vein complications in the 20 patients who underwent the new technique (7 months). The current method appears to be technically feasible for outflow reconstruction in left liver graft transplantation.

Hepatectomy for hepatocellular carcinoma after perioperative management of portal hypertension

BACKGROUND

Indications for hepatectomy in patients with hepatocellular carcinoma (HCC) who have portal hypertension (PH) have been controversial. Some studies have concluded that PH is a contraindication to hepatectomy, whereas others have suggested that perioperative prophylactic management (PPM) can help overcome complications after hepatectomy associated with PH. The objective of this retrospective study was to assess the short- and long-term outcomes after hepatectomy for HCC in patients with PH, with or without PPM.

METHODS

Records were reviewed of consecutive patients who underwent hepatectomy for HCC, with or without PPM of PH, in a single institution from 1994 to 2015. Patients were divided into three groups: those who received PPM for PH (PPM group), patients who had PH but did not receive PPM (no-PPM group) and those without PH (no-PH group).

RESULTS

A total of 1259 patients were enrolled, including 123 in the PPM group, 181 in the no-PPM group and 955 in the no-PH group. Three- and 5-year overall survival rates were 74·3 and 53·1 per cent respectively in the PPM group, 69·2 and 54·9 per cent in the no-PPM group, and 78·1 and 64·2 per cent in the no-PH group (P = 0·520 for PPM versus no PPM, P = 0·027 for PPM versus no PH, and P < 0·001 for no PPM versus no PH). Postoperative morbidity and mortality rates were 26·0 and 0·8 per cent respectively in the PPM group, 29·8 and 1·1 per cent in the no-PPM group, and 20·3 and 0 per cent in the no-PH group.

CONCLUSION

The present study has demonstrated acceptable outcomes among patients with HCC who received appropriate management for PH in an Asian population. Enhancement of the safety of hepatic resection through use of PPM may provide a rationale for expansion of indications for hepatectomy in patients with PH.

IMP-68, a Novel IMP-Type Metallo-β-Lactamase in Imipenem-Susceptible Klebsiella pneumoniae

We recently detected a novel variant of an IMP-type metallo-β-lactamase gene (blaIMP-68) from meropenem-resistant but imipenem-susceptible Klebsiella pneumoniae TA6363 isolated in Tokyo, Japan. blaIMP-68 encodes a Ser262Gly point mutant of IMP-11, and transformation experiments showed that blaIMP-68 increased the MIC of carbapenems in recipient strains, whereas the MIC of imipenem was not greatly increased relative to that of other carbapenems, including meropenem. Kinetics experiments showed that IMP-68 imipenem-hydrolyzing activity was lower than that for other carbapenems, suggesting that the antimicrobial susceptibility profile of TA6363 originated from IMP-68 substrate specificity. Whole-genome sequencing showed that blaIMP-68 is harbored by the class 1 integron located on the IncL/M plasmid pTMTA63632 (88,953 bp), which was transferable via conjugation. The presence of plasmid-borne blaIMP-68 is notable, because it conferred antimicrobial resistance to carbapenems, except for imipenem, on Enterobacteriaceae and will likely affect treatment plans using antibacterial agents in clinical settings.IMPORTANCE IMP-type metallo-β-lactamases comprise one group of the "Big 5" carbapenemases. Here, a novel blaIMP-68 gene encoding IMP-68 (harboring a Ser262Gly point mutant of IMP-11) was discovered from meropenem-resistant but imipenem-susceptible Klebsiella pneumoniae TA6363. The Ser262Gly substitution was previously identified as important for substrate specificity according to a study of other IMP variants, including IMP-6. We confirmed that IMP-68 exhibited weaker imipenem-hydrolyzing activity than that for other carbapenems, demonstrating that the antimicrobial susceptibility profile of TA6363 originated from IMP-68 substrate specificity, with this likely to affect treatment strategies using antibacterial agents in clinical settings. Notably, the carbapenem resistance conferred by IMP-68 was undetectable based on the MIC of imipenem as a carbapenem representative, which demonstrates a comparable antimicrobial susceptibility profile to IMP-6-producing Enterobacteriaceae that previously spread in Japan due to lack of awareness of its existence.

Repeat hepatectomy for recurrent liver metastasis from gastric carcinoma

BACKGROUND

The efficacy of repeat hepatectomy for recurrent hepatocellular carcinoma and colorectal liver metastases is widely accepted. However, the benefits of such treatment for intrahepatic recurrence of gastric cancer liver metastasis remain unknown. This study sought to clarify the survival benefit for patients undergoing repeat hepatectomy for gastric cancer liver metastasis.

METHODS

A total of 73 patients underwent hepatectomy for gastric cancer liver metastasis from January 1993 to January 2011. Macroscopically curative surgery was performed in 64 patients. Among them, repeat hepatectomy was performed in 14 of the 37 patients with intrahepatic recurrence. Among these 14 patients, clinicopathologic factors were evaluated by univariate and multivariate analysis to identify the factors affecting survival.

RESULTS

The overall 1-, 3-, and 5-year survival rates after a second hepatectomy were 71, 47, and 47 %, respectively. The median survival was 31 months. Operative morbidity and mortality rates of repeat hepatectomy were 29 and 0 %, respectively. Multivariate analysis identified the duration of the disease-free interval as the only independent significant factor predicting better survival.

CONCLUSIONS

In selected patients, repeat hepatectomy for recurrent gastric cancer liver metastasis may offer the same chance of cure as the primary hepatectomy. Disease-free intervals exceeding 12 months predict good patient survival after repeat hepatectomy.

Difference in treatment algorithms for hepatocellular carcinoma between world's principal guidelines

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the second leading cause of cancer-related death globally. Clinical guidelines for HCC have been established and revised by many countries and regions. We summarized and compared the treatment algorithms in the updated HCC guidelines established by Japan, China, Hong Kong, the Asian-Pacific Association for the Study of the Liver, the American Association for the Study of Liver Diseases, and the European Association for the Study of the Liver and European Organization for Research and Treatment of Cancer. Variations in treatment algorithms between the guidelines is inevitable, considering the differences in the prevalence and etiology of HCC, local clinical practice, and medical and insurance systems between countries or regions, and this might be confusing for practitioners worldwide. A comprehensive understanding of the guidelines that are globally available might be useful for future improvement of each guideline.

Arterial blood supply to the pancreas from accessary middle colic artery

BACKGROUND

An accessory middle colic artery (AMCA) is an aberrant artery feeding the splenic flexure of the colon. Little is known about the branching pattern of an AMCA. We aimed to evaluate the branching pattern of the AMCA from the superior mesenteric artery (SMA) with special reference to the pancreatic artery using multidetector-row computed tomography (MDCT) before surgery.

METHODS

We investigated 112 patients who underwent contrast-enhancement MDCT before surgical resection of the pancreas between January 2015 and July 2018. The pancreatic branch from the AMCA was divided into the dorsal pancreatic artery (DPA) and the inferior pancreaticoduodenal artery (IPDA). The branching level and angle of the AMCA from the SMA were also evaluated.

RESULTS

The AMCA was present in 27.7% of patients (n = 31/112). The AMCA branching pattern was classified into four types: type A, no branch from the AMCA (n = 20); type B, a common trunk with the DPA (n = 6); type C, a common trunk with the IPDA (n = 3); and type D, a common trunk with the DPA and IPDA (n = 2). The AMCA with the IPDA (types C and D) branched more proximally compared to the AMCA without the IPDA (P = 0.04). The AMCA branched vertically from the SMA in most cases (n = 24/31, 77.4%).

CONCLUSIONS

The AMCA had a pancreatic branch in 8.9% (10/112) of cases. Special attention should be paid to its branching pattern in pancreatic and colon surgery.

Optimal diagnostic method using multidetector-row computed tomography for predicting lymph node metastasis in colorectal cancer

Background

Prediction of nodal involvement in colorectal cancer is an important aspect of preoperative workup to determine the necessity of preoperative treatment and the adequate extent of lymphadenectomy during surgery. This study aimed to investigate newer multidetector-row computed tomography (MDCT) findings for better predicting lymph node (LN) metastasis in colorectal cancer.

Methods

Seventy patients were enrolled in this study; all underwent MDCT prior to surgery and upfront curative resection for colorectal cancer. LNs with a short-axis diameter (SAD) ≥ 4 mm were identified on MDCT images, and the following measures were recorded by two radiologists independently: two-dimensional (2D) SAD, 2D long-axis diameter (LAD), 2D ratio of SAD to LAD, 2D CT attenuation value, three-dimensional (3D) SAD, 3D LAD, 3D SAD to LAD ratio, 3D CT attenuation value, LN volume, and presence of extranodal neoplastic spread (ENS), as defined by indistinct nodal margin, irregular capsular enhancement, or infiltration into adjacent structures.

Results

Forty-six patients presented 173 LNs with a SAD ≥ 4 mm, while 24 patients exhibited pathologically confirmed LN metastases. Receiver operating characteristic analysis revealed that 2D LAD was the most sensitive measure for LN metastases with an area under the curve of 0.752 (cut-off value, 7.05 mm). When combined with CT findings indicating ENS, 2D LAD (> or ≤ 7 mm) showed enhanced predictive power for LN metastases (area under the curve, 0.846; p < 0.001).

Conclusions

LAD in axial MDCT imaging is the most sensitive measure for predicting colorectal LN metastases, especially when MDCT findings of ENS are observed.

Multiple cancer type classification by small RNA expression profiles with plasma samples from multiple facilities

Liquid biopsy is expected to be a promising cancer screening method because of its low invasiveness and the possibility of detecting multiple types in a single test. In the last decade, many studies on cancer detection using small RNAs in blood have been reported. To put small RNA tests into practical use as a multiple cancer type screening test, it is necessary to develop a method that can be applied to multiple facilities. We collected samples of eight cancer types and healthy controls from 20 facilities to evaluate the performance of cancer type classification. A total of 2,475 cancer samples and 496 healthy control samples were collected using a standardized protocol. After obtaining a small RNA expression profile, we constructed a classification model and evaluated its performance. First, we investigated the classification performance using samples from five single facilities. Each model showed areas under the receiver curve (AUC) ranging from 0.67 to 0.89. Second, we performed principal component analysis (PCA) to examine the characteristics of the facilities. The degree of hemolysis and the data acquisition period affected the expression profiles. Finally, we constructed the classification model by reducing the influence of these factors, and its performance had an AUC of 0.76. The results reveal that small RNA can be used for the classification of cancer types in samples from a single facility. However, interfacility biases will affect the classification of samples from multiple facilities. These findings will provide important insights to improve the performance of multiple cancer type classifications using small RNA expression profiles acquired from multiple facilities.

Long-term results of hepatic resection for non-colorectal, non-neuroendocrine liver metastasis

BACKGROUND/AIMS

The significance of surgical resection for non-colorectal non-neuroendocrine tumor liver metastasis (NCNNLM) remains controversial. The present study sought to clarify the long-term outcomes of surgical resection for NCNNLM and prognostic factors after hepatectomy in a single institution.

METHODOLOGY

From 1993 to 2009, 145 patients underwent hepatectomy for NCNNLM. The primary sites of the hepatic tumors were gastrointestinal carcinoma in 80 cases, breast in 30, genitourinary in 12, gastrointestinal stromal tumor in 11, and miscellaneous in 12.

RESULTS

The cumulative 1-, 3-, and 5-year overall survival rates of those who underwent hepatectomy for NCNNLM were 83.9, 55.4, and 41.0%, respectively, with median overall survival times of 41.8 months. Multivariate analysis revealed that postoperative complication was the only independent poor prognostic factor impacting on survival. Postoperative morbidity and mortality rate were 17.9% and 1.4%. There are 38 cases survived more than 5 years including 21 patients without remnant tumors due to the repeat hepatic and/or pulmonary resection for recurrence. A total of 32 patients survived without tumor and without any kinds of chemotherapy in the latest condition.

CONCLUSIONS

Hepatectomy for NCNNLM may be beneficial and might relieve patients from excursive chemotherapy in selected patients. Meticulous surgery avoiding complication may enhance the outcome.

Application of indocyanine green-fluorescence imaging to full-thickness cholecystectomy

Fluorescence imaging using indocyanine green (ICG) has recently been applied to laparoscopic surgery to identify cancerous tissues, lymph nodes, and vascular anatomy. Here we report the application of ICG-fluorescence imaging to visualize the boundary between the liver and subserosal tissues of the gallbladder during laparoscopic full-thickness cholecystectomy. A patient with a potentially malignant gallbladder lesion was administered 2.5-mg intravenous ICG just before laparoscopic full-thickness cholecystectomy. Intraoperative fluorescence imaging enabled the real-time delineation of both extrahepatic bile duct anatomy and hepatic parenchyma throughout the procedure, which resulted in complete removal of subserosal tissues between liver and gallbladder. Safe and feasible ICG-fluorescence imaging can be widely applied to laparoscopic hepatobiliary surgery by utilizing a biliary excretion property of ICG.

Protocol of the RACB study: a multicenter, single-arm, prospective study to evaluate the efficacy of resection of initially unresectable hepatocellular carcinoma with atezolizumab combined with bevacizumab

BACKGROUND

Although the standard therapy for advanced-stage hepatocellular carcinoma (HCC) is systemic chemotherapy, the combination of atezolizumab and bevacizumab (atezo + bev) with a high objective response rate may lead to conversion to resection in patients with initially unresectable HCC. This study aims to evaluate the efficacy of atezo + bev in achieving conversion surgery and prolonged progression-free survival (PFS) for initially unresectable HCC.

METHODS

The RACB study is a prospective, single-arm, multicenter, phase II trial evaluating the efficacy of combination therapy with atezo + bev for conversion surgery in patients with technically and/or oncologically unresectable HCC. The main eligibility criteria are as follows: (1) unresectable HCC without a history of systemic chemotherapy, (2) at least one target lesion based on RECIST ver. 1.1, and (3) a Child‒Pugh score of 5-6. The definition of unresectable tumors in this study includes macroscopic vascular invasion and/or extrahepatic metastasis and massive distribution of intrahepatic tumors. Patients will be treated with atezolizumab (1200 mg/body weight) and bevacizumab (15 mg/kg) every 3 weeks. If the patient is considered resectable on radiological assessment 12 weeks after initial chemotherapy, the patient will be treated with atezolizumab monotherapy 3 weeks after combination chemotherapy followed by surgery 3 weeks after atezolizumab monotherapy. If the patient is considered unresectable, the patient will continue with atezo + bev and undergo a radiological assessment every 9 weeks until resectable or until disease progression. The primary endpoint is PFS, and the secondary endpoints are the overall response rate, overall survival, resection rate, curative resection rate, on-protocol resection rate, and ICG retention rate at 15 min after atezo + bev therapy. The assessments of safety and quality of life during the treatment course will also be evaluated. The number of patients has been set at 50 based on the threshold and the expected PFS rate at 6 months after enrollment of 40% and 60%, respectively, with a one-sided alpha error of 0.05 and power of 0.80. The enrollment and follow-up periods will be 2 and 1.5 years, respectively.

DISCUSSION

This study will elucidate the efficacy of conversion surgery with atezo + bev for initially unresectable HCC. In addition, the conversion rate, safety and quality of life during the treatment course will also be demonstrated.

TRIAL REGISTRATION

This study is registered in the Japan Registry of Clinical Trials (jRCTs051210148, January 7, 2022).