Masami Tabata

Clinicopathological features and prognosis of mucin‐producing bile duct tumor and mucinous cystic tumor of the liver: a multi‐institutional study by the Japan Biliary Association

The aim of this study was to determine the clinicopathological features and surgical outcomes of mucinous cystic neoplasm of the liver (MCN) and mucin‐producing intraductal papillary neoplasm of the intrahepatic bile duct (M‐IPNB).

S4a + S5 with caudate lobe (S1) resection using the Taj Mahal liver parenchymal resection for carcinoma of the biliary tract.

Recently we have been performing S4a + S5 with total resection of the caudate lobe (SI) by using a dome-like dissection along the root of the middle hepatic vein at the pinnacle, which we refer to as the Taj Mahal liver parenchymal resection, for carcinoma of the biliary tract. This procedure offers the following advantages: (1) It allows total resection of the caudate lobe, including the paracaval portion (S9), and (2) because the cut surface of the liver is large, it allows intrahepatic jejunostomy to be performed more easily with a good field of view. The indications for this procedure include hilar bile duct carcinoma, gallbladder carcinoma, and choledochal cyst (type IVA). Because of the high rate of hilar liver parenchyma and caudate lobe invasion associated with hilar bile duct carcinoma, the liver must be resected. The Taj Mahal procedure is indicated in cases where extended liver resection is impossible. The dissection limits of this procedure are, on the left side, the B2 + 3 bifurcation at the right margin of the umbilical portion of the portal vein and, on the right side, the B8 of the anterior branch and the B6+7 bifurcation of the right posterior branch. This procedure could also be described as a reduced form of extended right hepatectomy and extended left hepatectomy. For gallbladder carcinoma, this procedure is indicated to ensure an adequate surgical margin and eradicate transvenous liver metastasis, particularly in cases of pT2 lesions. Hilar and caudate lobe invasion also occurs in liver bed-type gallbladder carcinoma, and bile duct resection and caudate lobe resection are required for the surgery to be curative. We performed this procedure in four cases of hilar bile duct carcinoma, five cases of gallbladder carcinoma, and one case each of choledochal cyst (type IVA) with carcinoma of the bile duct and gallbladder adenomyomatosis. Curative resection was possible in all except the patient with adenomyomatosis, and all of the patients are alive and recurrence free 10 to 37 months postoperatively. This procedure, in addition to preserving liver function, provides a wide field of view and facilitates reconstruction of multiple intrahepatic bile ducts. Thus it can be said to be a curative operation not only in patients considered high risk but also in those whose hilar bile duct carcinoma is limited to the bifurcation area (Bismuth type IIIa and IIIb) and in gallbladder carcinoma up to pT2 with slight extension on the hepatic side.

Donor outcome and liver regeneration after right-lobe graft donation.

Sufficiently detailed information on donor safety and the liver regeneration process following right‐lobe living donation has been unavailable, so we evaluated donor outcome and liver regeneration in 13 males and 14 females (39.0 ± 14.8 years old) who provided 27 right‐lobe grafts without the middle hepatic vein. Preoperative total liver volume (TLV), graft volume, and postoperative changes in residual liver volume (RLV) were measured by volumetric computed tomography. Histological steatosis of the liver was graded as none, minimal (≤10%), and mild (11–30%). The median follow‐up period was 337 days. Estimated graft volume and actual graft weight were linearly correlated (Y = 177.85 + 0.795X, R2 = 0.812, P < 0.0001). Graft‐to‐recipient weight ratio was 1.08 ± 0.19%. Four donors had postoperative complications, but they resolved in response to conservative treatment. Postoperative hospital stay was 15.2 ± 5.5 days. Peak liver enzyme values were significantly higher in donors with mild steatosis (n = 7) than without steatosis (n = 16) (P < 0.05). Donor RLV was 40.8 ± 6.6% of original TLV at surgery, 79.8 ± 12.0% by 6 months, and 97.2 ± 10.8% by 12 months. At 3 months the liver of the older donors (≥50 years) had grown significantly more slowly than in younger donors (70.4 ± 9.2% vs. 79.3 ± 9.6%, P = 0.0391). In conclusion, right hepatectomy without middle hepatic vein of living donors is a safe procedure with acceptable morbidity, and the residual liver regenerated to its preoperative size by 1 year. However, meticulous care should be taken in donors with liver steatosis and aged donors.

Surgical Treatment of Hilar Bile Duct Carcinoma: Experience With 25 Consecutive Hepatectomies

To evaluate our recent surgical policy regarding hilar bile duct carcinoma, we evaluated 62 cases treated between 1976 and 1993, and 25 cases treated between 1994 and 2000. In the late period we used percutaneous transhepatic portal vein embolization (PTPE) before extended right hepatectomy; S4a + S5 + S1 hepatectomy for elderly patients and those with poor liver function; and routine total caudate lobectomy including the paracaval portion and resection of the inferior portion of the medial segment (S4a). Sixtyfive (74.7%) of the 87 patients underwent hepatectomy: 40 in the early period and 25 in the late period. Bile duct resection alone was performed in 22 patients, all in the early period. Resection was curative in 54.8% in the early period and 88.0% in the late period. The 3- and 5-year survival rates in the early period were 27.1% and 20.2%, respectively, as compared to 59.9% and 49.9% in the late period. Analysis of the 25 hepatectomies in the late period revealed improved survival times compared to patients treated by PTPE with extended right hepatectomy. No complications occurred after extended left hepatectomy or S4a + S5 + S1 hepatectomy, but four patients (16%) who underwent extended right hepatectomy plus PTPE died postoperatively. Our policy has resulted in improved outcome in patients with hilar bile duct carcinoma.

Effect of Hepatic Invasion on the Choice of Hepatic Resection for Advanced Carcinoma of the Gallbladder: Histologic Analysis of 32 Surgical Cases

Abstract. The purpose of this study was to assess the patterns of hepatic invasion in advanced carcinoma of the gallbladder by histologically examining surgical specimens obtained in 32 cases of hepatectomy for that carcinoma. Two modes of microscopic tumor extension were observed. The expansive pattern was restricted to liver-bed carcinomas, in which the tumor extends into the liver, primarily from the liver bed. Most of the infiltrating patterns were found with hepatic-hilar carcinomas, in which the tumor invades the hepatic hilum along Glisson’s sheath, especially tumors exhibiting a discontinuous front of tumor invasion. The average width for wedge resection of the liver bed was 15.6 ± 2.9 mm, in contrast to 25.6 ± 8.1 mm for resection of segments IVa and V and 44.1 ± 10.3 mm for extensive hepatic resection (bothp < 0.01). When the hepatic invasion distance is more than 20 mm, the tumor should be selectively managed by extensive hepatic resection, such as extended right hepatic lobectomy or central bisegmentectomy. The results suggest that wedge resection of the liver bed and resection of segments IVa and V are advisable for carcinoma localized to the gallbladder alone and for liver-bed carcinoma with slight hepatic invasion and an expansive tumor growth pattern. Extensive hepatic resection, however, is recommended for carcinoma of the invasive liver-bed type and carcinoma of the hepatic-hilar type.

Clinical practice guidelines for the management of biliary tract cancers 2015: the 2nd English edition

The Japanese Society of Hepato‐Biliary‐Pancreatic Surgery launched the clinical practice guidelines for the management of biliary tract and ampullary carcinomas in 2008. Novel treatment modalities and handling of clinical issues have been proposed after the publication. New approaches for editing clinical guidelines, such as the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system, also have been introduced for better and clearer grading of recommendations.

Laparoscopic Spleen-Preserving Pancreatic Tail Resection for an Intrapancreatic Accessory Spleen Mimicking a Nonfunctioning Endocrine Tumor: Report of a Case

Laparoscopic surgery is now performed for several pancreatic disorders, such as benign tumors of the pancreatic body or tail, which are a good indication for laparoscopic resection. However, the risk of pancreatic fistula after distal pancreatectomy, performed laparoscopically or by open surgery, is a topic of debate. We report the case of a 61-year-old man in whom a routine follow-up computed tomography (CT) scan showed a solid, well-defined mass, 1.5 cm in diameter, in the pancreatic tail. The mass was homogeneously enhanced from the early phase to the super-delayed phase on enhanced CT. We suspected a nonfunctioning endocrine tumor of the pancreas, and surgery was performed laparoscopically. After dissecting the pancreatic tail away from the splenic hilum and the splenic vessels, it was resected using only a linear stapler. The histological diagnosis was an intrapancreatic accessory spleen. The patient was discharged on postoperative day 14, but was readmitted 6 days later because of a pancreatic fistula, which was treated by CT-guided percutaneous drainage.

The Cytoprotective Effects of Addition of Activated Protein C into Preservation Solution on Small-for-Size Grafts in Rats

Small‐for‐size liver grafts are a serious obstacle for partial orthotopic liver transplantation. Activated protein C (APC), a potent anticoagulant serine protease, is known to have cell‐protective properties due to its anti‐inflammatory and antiapoptotic activities. This study was designed to examine the cytoprotective effects of a preservation solution containing APC on small‐for‐size liver grafts, with special attention paid to ischemia‐reperfusion injury and shear stress in rats. APC exerted cytoprotective effects, as evidenced by (1) increased 7‐day graft survival; (2) decreased initial portal pressure and improved hepatic microcirculation; (3) decreased levels of aminotransferase and improved histological features of hepatic ischemia‐reperfusion injury; (4) suppressed infiltration of neutrophils and monocytes/macrophages; (5) reduced hepatic expression of tumor necrosis factor α and interleukin 6; (6) decreased serum levels of hyaluronic acid, which indicated attenuation of sinusoidal endothelial cell injury; (7) increased hepatic levels of nitric oxide via up‐regulated hepatic endothelial nitric oxide synthesis expression together with down‐regulated hepatic inducible nitric oxide synthase expression; (8) decreased hepatic levels of endothelin 1; and (9) reduced hepatocellular apoptosis by down‐regulated caspase‐8 and caspase‐3 activities. These results suggest that a preservation solution containing APC is a potential novel and safe product for small‐for‐size liver transplantation, alleviating graft injury via anti‐inflammatory and antiapoptotic effects and vasorelaxing conditions. Liver Transpl 16:1–11, 2010.

Surgical treatment of type IV choledochal cysts

The benefit of total resection of the dilated bile duct has remained unclear. We describe here our surgical management of 13 patients with type IV choledochal cysts. All six younger patients (25-35 years old) underwent resection of the extrahepatic bile duct (EHBD) and hepaticojejunostomy (HJ), whereas three of the seven older patients (50-68 years old) underwent resection of the EHBD resection and HJ, with the remaining four older patients undergoing total resection of the dilated bile duct and removal of a pancreatobiliary maljunction (PBMJ) in the form of a S4a+S5 hepatectomy (so-called Taj Mahal) and/or pancreas head resection with second portion pancreaticoduodenectomy. No malignancies were detected in the dilated bile duct after resection in the younger patients, but cancer of the gallbladder and/or the dilated bile duct was found in two (27.5%) of the older patients. No cancers were detected during the long-term follow up (1974-2008) in those patients who underwent EHBD resection plus partial hepatectomy, but cancer developed in the remnant duct in one of the older patients who underwent EHBD resection alone. Based on our findings, we recommend that type IV choledochal cysts should be treated by total excision of the dilated bile duct, including the PBMJ, due to its frequent association with malignancy, and to prevent the development of cancer in the remnant duct and improve the long-term survival rate.

Intrahepatic Hepatic Vein Stenosis After Living‐Related Liver Transplantation Treated by Insertion of an Expandable Metallic Stent

Although the incidence of stenosis and obstruction of the hepatic venous anastomosis after right hepatic living‐related liver transplantation (LRLT) has been found to be higher than after orthotopic liver transplantation (OLT), to the best of our knowledge, intrahepatic stenosis of the venous trunk in the early period after right hepatic LRLT has never been reported in the literature. A 53‐year‐old man who underwent right hepatic LRLT, postoperatively, developed liver dysfunction and an increasing amount of ascites, and a Doppler sonogram showed a flat waveform and low‐flow velocity in the hepatic vein. Based on these findings an outflow block was suspected, and a hepatic venogram and manometry revealed intrahepatic stenosis of a tortuous hepatic venous trunk and a pressure gradient of 14 mmHg at the site of the stenosis. We inserted an expandable metallic stent (EMS) at the site of intrahepatic venous stenosis, and its insertion was followed by a decrease in pressure gradient. Liver function recovered, and the volume of ascitic fluid decreased after placement of the EMS. The results of an analysis of the venogram and CT volumetric data suggested that the pathogenesis of the stenosis was twisting of the venous trunk during hypertrophy of the liver parenchyma.