Yosuke Inoue

Sinistral portal hypertension after pancreaticoduodenectomy with splenic vein ligation.

Splenic vein ligation may result in sinistral (left‐sided) portal hypertension and gastrointestinal haemorrhage. The aim of this study was to analyse the pathogenesis of sinistral portal hypertension following splenic vein ligation in pancreaticoduodenectomy.

RAS mutation is a prognostic biomarker in colorectal cancer patients with metastasectomy.

Studies have demonstrated a relationship between clinical outcomes after curative resection for colorectal cancer (CRC) and gene mutations of the EGFR pathway; however, no studies have examined metastatic CRC (mCRC) patients with metastasectomy. The aim of this study was to evaluate the relationship between gene mutations of EGFR pathway and clinical outcomes after metastasectomy in mCRC patients. A total of 1,053 patients histopathologically confirmed CRC received a genotyping test for the EGFR pathway from February 2012 to October 2013. Detailed information was obtained through review of medical records. Gene mutations of EGFR pathway were analyzed by Luminex assay. Overall survival (OS) and recurrence free survival were estimated by the Kaplan‐Meier method and the log‐rank test was used to compare the survival outcomes by gene mutation status. A total of 132 patients received metastasectomy. The frequencies of KRAS exon 2, KRAS exon 3.4, NRAS, BRAF, and PIK3CA mutations were 38.6% (51/132), 3.6% (5/132), 5.1% (7/132), 5.1% (7/132), and 8.7% (12/132), respectively. With a median follow‐up of 84.1 months (57.2—NA) for a survivor, the 4‐year OS rate was 65.6% for mCRC with RAS mutation, and 81.3% for mCRC with wild‐type RAS (p < 0.05). We observed a statistically significant correlation for only the RAS mutation and OS. In multivariate analysis, RAS mutation and liver metastasis were independent factors for shorter OS. There were no significant differences between gene mutations of EGFR pathway and recurrence free survival. RAS mutation in mCRC metastasectomy patients was associated with shorter overall survival.

Technical Details of an Anterior Approach to the Superior Mesenteric Artery During Pancreaticoduodenectomy.

IntroductionUse of central vascular ligation during dissection around the superior mesenteric artery (SMA) in pancreaticoduodenectomy (PD) for periampullary malignancies has rarely been documented.MethodsWe developed the SMA hanging technique (SHT) to facilitate central vascular ligation during PD. Briefly, SMA dissection was initiated using the supracolic anterior approach, followed by left-sided dissection. The SMA was taped under finger guidance immediately after right-sided dissection. The ligament of Treitz was detached from the SMA during left-sided dissection, facilitating adequate lymph node dissection while preserving the nerve plexus around the SMA. Forty-seven consecutive patients who underwent PD for periampullary malignancies were divided into two groups: 23 underwent SHT and 24 underwent conventional dissection. Patients’ clinical results were assessed to evaluate the feasibility and validity of SHT.ResultsBlood loss volume, operation duration, and the incidence of bleeding during SMA dissection were significantly lower in the SHT group than in the conventional group. The short-term and oncological results were similarly acceptable in both groups.ConclusionsSHT is a feasible and safe technique with acceptable short-term outcomes. We propose the use of this procedure to standardize en bloc dissection around the SMA.

Elastography for hepato-biliary-pancreatic surgery

Palpation is a subjective and non-sharable diagnostic method. Recently, palpation has been supported and replaced by elastography, which provides a novel parameter of “stiffness” as a visual representation or quantified value. Today, elastography is performed using two major modalities: strain elastography and shear wave elastography. Strain elastography converts the extent of deformation during external compression into colors, displaying these colors as a strain map in a motion picture representing the relative elasticity inside the region of interest. Shear wave elastography can quantify the elasticity of a target by calculating the velocity of shear waves generated by a probe. In addition to superficial organs, elastography has also been applied to upper abdominal organs, including the liver, pancreas and spleen. The visualization of the stiffness of focal lesions in the liver or the pancreas has enabled a more sensitive and specific depiction of small, non-palpable nodules, which are difficult to depict using B-mode ultrasonography. The quantification of stiffness also enables non-invasive estimates of liver fibrosis, the risk of postoperative liver insufficiency and the risk of recurrence of viral hepatitis after transplantation. In this article, we review the major reports that have recently been published describing the effective application of elastography to solid upper abdominal organs in a clinical setting.

Surgical Anatomy of the Superior Mesenteric Vessels Related to Pancreaticoduodenectomy: a Systematic Review and Meta-Analysis

Background and PurposeMesopancreas dissection with central vascular ligation and the superior mesenteric artery (SMA)-first approach represent the cornerstone of current principles for radical resection for pancreatic head cancer. The surgeon dissecting around the SMV and SMA should be aware regarding the anatomical variants in this area. The aims of this systematic review and meta-analysis are to detail the surgical anatomy of the superior mesenteric vessels and to propose a standardized terminology with impact in pancreatic cancer surgery.MethodsWe conducted a systematic search to identify all published studies in PubMed/MEDLINE and Google Scholar databases from their inception up to March 2017.ResultsSeventy-eight studies, involving a total of 18,369 specimens, were included. The prevalence of the mesenteric-celiac trunk, replaced/accessory right hepatic artery (RRHA), common hepatic artery, and SMV inversion was 2.8, 13.2, 2.6, and 4.1%, respectively. The inferior pancreaticoduodenal artery has its origin into the first jejunal artery, SMA, and RRHA, in 58.7, 35.8, and 1.2% of cases, respectively. The SMV lacks a common trunk in 7.5% of cases. The first jejunal vein has a trajectory posterior to the SMA in 71.8% of cases. The left gastric vein drains into the portal vein in 58%, in splenic vein (SV) in 35.6%, and into the SV-PV confluence in 5.8% of cases.ConclusionsComplex pancreaticoduodenal resections require detailed knowledge of the superior mesenteric artery and vein, which is significantly different from the one presented in the classical textbooks of surgery. We are proposing the concept of the first jejunopancreatic vein which impacts the current oncological principles of pancreatic head cancer resection.

Surgical Anatomy of the Superior Mesenteric Vessels Related to Colon and Pancreatic Surgery: A Systematic Review and Meta-Analysis

The surgeon dissecting the base of the mesenterium, around the superior mesenteric vein (SMV) and artery, is facing a complex tridimensional vascular anatomy and should be aware of the anatomical variants in this area. The aim of this systematic review is to propose a standardized terminology of the superior mesenteric vessels, with impact in colon and pancreatic resections. We conducted a systematic search in PubMed/MEDLINE and Google Scholar databases up to March 2017. Forty-five studies, involving a total of 6090 specimens were included in the present meta-analysis. The pooled prevalence of the ileocolic, right colic and middle colic arteries was 99.8%, 60.1%, and 94.6%, respectively. The superior right colic vein and Henle trunk were present in 73.9%, and 89.7% of specimens, respectively. In conclusion, the infra-pancreatic anatomy of the superior mesenteric vessels is widely variable. We propose the term Henle trunk to be used for any venous confluence between gastric, pancreatic and colic veins, which drains between the inferior border of the pancreas and up to 20 mm downward on the right-anterior aspect of the SMV. The term gastrocolic trunk should not be synonymous, but a subgroup of the Henle trunk, together with to gastropancreatocolic, gastropancreatic, or colopancreatic trunk.

Laparoscopic deroofing for polycystic liver disease using laparoscopic fusion indocyanine green fluorescence imaging

AbstractBackgroundLaparoscopic deroofing is widely used for the treatment of symptomatic polycystic liver disease (PCLD). However, bile leakage is a common complication of surgical management for PCLD. Until now, indocyanine green fluorescence imaging (IGFI) has played an active role in hepatobiliary surgery. Herein, we report the effective application of a laparoscopic fusion IGFI system, known as PINPOINT, for laparoscopic deroofing. MethodsIn this study, we performed laparoscopic deroofing for PCLD using the laparoscopic fusion IGFI system. We conducted the procedure mainly under the normal view mode, occasionally switching to the fusion IGFI mode. First, we confirmed that the liver cysts did not contain bile using the fusion IGFI mode and then used a percutaneous puncture needle to remove the fluid from some of the giant cysts. Second, using the fusion IGFI mode, we were able to detect thin biliary branches and to adjust the division line of the cyst wall accordingly or, occasionally, to ligate the branches. Finally, we searched for and identified unexpected small bile leakage and then closed it using sutures.ResultsThe laparoscopic fusion IGFI system can simultaneously show fluorescent images, such as cholangiography and the liver parenchyma, on the normal color view. In the fusion IGFI mode, the intrahepatic bile duct and liver parenchyma can be easily discriminated in real time throughout the procedure. Accordingly, the laparoscopic fusion IGFI system is useful for the surgical treatment of PCLD, in which the boundary between the liver cysts and the liver parenchyma can otherwise be difficult to identify. This technique also enables the branches of Glisson’s capsule to be identified without any other intervention.ConclusionThe novel application of the laparoscopic fusion IGFI system allows reliable navigation for PCLD surgery.

Recurrence 30 Years after Surgical Resection of a Localized Rectal Neuroendocrine Tumor

Localized small rectal neuroendocrine tumors (NETs) without any vascular involvement rarely metastasize, and their resection alone is considered curative. We herein report a case of localized rectal NET (10×8 mm) without vascular involvement. Although resected initially, it recurred as liver metastasis 30 years later. For rectal NETs smaller than 10 to 20 mm, surveillance for 12 months is considered sufficient. However, this case suggests that such tumors can recur even 30 years after curative resection. The interval of recurrence is the longest among reported cases.

A Novel Classification and Staged Approach for Dissection Along the Celiac and Hepatic Artery During Pancreaticoduodenectomy

BackgroundIn recent decades, there have been enthusiastic discussions of, and active proposals for, new approaches to dissection around the superior mesenteric artery during pancreaticoduodenectomy (PD). In contrast, dissection along the celiac axis (CA) and hepatic artery (HA) and in the hepatoduodenal ligament has rarely been systematically discussed. In this report, we propose and describe a three-level classification of dissection along the CA-HA system which is applicable to a variety of diseases for which PD is indicated.MethodsThe extent of dissection is classified into three levels. With the first level (LV-1), neither LN nor plexus dissection is required. The second level (LV-2) includes en bloc resection of LNs along the CA, HA, and in the hepatoduodenal ligament, preserving the nerve plexus around the artery. The third level (LV-3) includes en bloc dissection of LNs and the nerve plexus close to cancer invasion, for example, being accompanied by half circumferential dissection of the nerve plexus around the CA or circumferential dissection of that of HA. LV-1 dissection is indicated for benign lesions, low grade malignancy, pancreatic metastasis, or intraductal papillary mucinous neoplasm. LV-2 is indicated for periampullary malignancies requiring dissection of regional LNs, including ampullary, distal bile duct, duodenal cancers, and pancreatic cancers without evidence of invasion around the CA-HA system. LV-3 is indicated for malignancies with evidence of perineural invasion in the CA-HA system, such as pancreatic cancer at the pancreatic neck or advanced bile duct cancer.ConclusionsIn combination with classified superior mesenteric artery dissection, a variety of PD procedures would be systematically classified, understood, and reproduced regardless of nature of disease, surgeon, or approach.

Response of the Authors to the Letter of the Editor Surgical Anatomy of the Superior Mesenteric Vessels Related to Pancreaticoduodenectomy: a Systematic Review and Meta-Analysis

Dear Editor, We thank doctor Pran et al. for their interest and very interesting comments regarding our article BSurgical Anatomy of the Superior Mesenteric Vessels Related to Pancreaticoduodenectomy: a Systematic review and Meta-Analysis^. As doctor Pran et al. commented, the posterosuperior pancreaticoduodenal vein (PSPDV) was indeed termed the vein of Belcher by Professor John Cameron, the well-known pioneer of pancreatic surgery from John Hopkins Hospital. Professor Cameron found the PSPDV to look like his assistant, Bshort, fat, and always in the way,^ Kenneth Belcher, hence the name. Kenneth Belcher was a personal assistant in the pancreatic service from John Hopkins and scrubbed with Professor Cameron in most of the Whipple’s he performed throughout his career. Although we are full of gratitude for the great minds of our surgical ancestors and really enjoy the history of surgery, we stand for worldwide standardization of the anatomy terms with impact in modern surgery. We agree about the importance of the PSPDV as an anatomical landmark during portal vein surgical dissection. On the other hand, during pancreaticoduodenectomy, we try to maintain the venous drainage of the surgical specimen after transection of the inferior pancreaticoduodenal artery, to prevent specimen congestion, oozing and a bloody surgical field. In conclusion, we fully agree with the comments made by Pran et al., who highlighted the importance of the meticulous surgical dissection and transection of the PSPDV.