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Featured researches published by Hajime Yokoi.


Radiology | 2008

Early-stage hepatocellular carcinoma: radiofrequency ablation combined with chemoembolization versus hepatectomy.

Koichiro Yamakado; Atsuhiro Nakatsuka; Haruyuki Takaki; Hajime Yokoi; Masanobu Usui; Hiroyuki Sakurai; Shuji Isaji; Katsuya Shiraki; Hiroyuki Fuke; Shinji Uemoto; Kan Takeda

PURPOSE To retrospectively evaluate the long-term results of radiofrequency (RF) ablation combined with chemoembolization (combination therapy) as compared with hepatectomy for the treatment of early-stage hepatocellular carcinoma (HCC). MATERIALS AND METHODS The study was approved by the institutional review board, and informed consent was waived. Patients with early-stage HCC were included if they underwent either combination therapy or hepatectomy and met the following inclusion criteria: no previous treatment for HCC, three or fewer tumors with a maximum diameter of 3 cm or less each or a single tumor with a maximum diameter of 5 cm or less, Child-Pugh class A liver profile, no vascular invasion, and no extrahepatic metastases. The primary endpoint was overall survival, and the secondary endpoint was recurrence-free survival. RESULTS One hundred four patients (mean age, 66.5 years +/- 8.7 [standard deviation]; 79 men, 25 women) underwent combination therapy, and 62 patients (mean age, 64.5 years +/- 9.6; 51 men, 11 women) underwent hepatectomy. The 1-, 3-, and 5-year overall survival rates following combination therapy (98%, 94%, and 75%, respectively) were similar (P = .87) to those following hepatectomy (97%, 93%, and 81%, respectively). The 1-, 3-, and 5-year recurrence-free survival rates were also comparable (P = .70) for combination therapy (92%, 64%, and 27%, respectively) and hepatectomy (89%, 69%, and 26%, respectively). CONCLUSION RF ablation combined with chemoembolization in patients with early-stage HCC provides overall and disease-free survival rates similar to those achieved by hepatectomy.


Journal of Gastrointestinal Surgery | 1999

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

Yoshifumi Kawarada; Shuji Isaji; Hiroki Taoka; Masami Tabata; Bidhan C. Das; Hajime Yokoi

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.


Transplant International | 2005

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

Hajime Yokoi; Shuji Isaji; Kentaro Yamagiwa; Masami Tabata; Hiroyuki Sakurai; Mosanobu Usui; Shugo Mizuno; Shinji Uemoto

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.


The American Journal of Gastroenterology | 1998

A case of inflammatory pseudotumor of the liver causing elevated serum CA19-9 levels

Tomoko Ogawa; Hajime Yokoi; Yoshifumi Kawarada

Inflammatory pseudotumor of the liver is a rare lesion characterized by proliferating fibrovascular tissue admixed with inflammatory cells. A 50-yr-old Japanese man was hospitalized because of upper abdominal pain and high fever. Computed tomography revealed a poorly demarcated, low density mass in the left lobe of the liver, and abnormal laboratory findings included WBC 9340/mm3, CRP 10.5 mg/dl, and marked elevation of CA19-9 to 1167.9 U/ml. Endoscopic retrograde cholangiography showed irregularity of the intrahepatic bile duct of the left lateral segment, and the lateral segmental branches of the portal vein were not visualized on the venous phase of abdominal angiography. Ultrasound-guided liver biopsy was performed, but malignant disease, including intrahepatic cholangiocarcinoma, could not be completely ruled out. The patient underwent left hepatic lobectomy with lymph node dissection. Histopathological examination yielded a definitive diagnosis of inflammatory pseudotumor. The lesion was immunohistochemically stained for CA19-9 by the ABC method, and the biliary epithelium in severely inflamed portal canals was found to be positive. The markedly elevated preoperative level of CA 19-9 decreased to almost within the normal range and the patient remains well 2 yr 9 months after surgery, without any complications.


Surgery Today | 2004

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

Takashi Hamada; Shuji Isaji; Shugo Mizuno; Masami Tabata; Kentaro Yamagiwa; Hajime Yokoi; Shinji Uemoto

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.


Journal of Gastroenterology and Hepatology | 2008

Survival rates according to the Cancer of the Liver Italian Program scores of 345 hepatocellular carcinoma patients after multimodality treatments during a 10-year period in a retrospective study.

Kentaro Yamagiwa; Katsuya Shiraki; Koichiro Yamakado; Shugo Mizuno; Tomohide Hori; Shinichiro Yagi; Takashi Hamada; Taku Iida; Ikuo Nakamura; Koji Fujii; Masanobu Usui; Shuji Isaji; Keiichi Ito; Shinsei Tagawa; Kan Takeda; Hajime Yokoi; Takashi Noguchi

Background and Aim:  The Cancer of the Liver Italian Program (CLIP) score has been demonstrated to have superior prognostic ability in hepatocellular carcinoma (HCC) patients worldwide, but there has never been sufficient assessment of the efficacy of treatment modalities according to the CLIP score. This retrospective cohort study of HCC patients was conducted to assess the efficacy of treatment modalities according to the CLIP score.


American Journal of Transplantation | 2004

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

Kentaro Yamagiwa; Hajime Yokoi; Shuji Isaji; Masami Tabata; Shugo Mizuno; Tomohide Hori; Koichiro Yamakado; Shinji Uemoto; Kan Takeda

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.


Clinical Transplantation | 2005

Outflow block secondary to stenosis of the inferior vena cava following living-donor liver transplantation?

Shugo Mizuno; Hajime Yokoi; Kentaro Yamagiwa; Masami Tabata; Shuji Isaji; Koichiro Yamakado; Kan Takeda; Shinji Uemoto

Abstract:  Although it is well known that outflow block is caused by stenosis or occlusion of hepatic vein anastomoses following living donor liver transplantation (LDLT), there have been few reports on inferior vena cava (IVC) stenosis following LDLT. In this paper, we report two cases of IVC stenosis and hepatic vein outflow block following right hepatic LDLT in the absence of stenosis of any of the anastomoses. Both patients presented with liver dysfunction, an ascitic fluid volume of approximately 2000 mL, and congestion in their biopsy specimens, and venocavography demonstrated IVC stenosis with gradients of more than 10 mmHg in patients with a dominant inferior right hepatic vein (IRHV) anastomosis. After a Gianturco expandable metallic stent successfully implanted in the IVC, the patients liver function recovered and the volume of ascitic fluid decreased. The pathogenesis of hepatic vein outflow block secondary to IVC stenosis following LDLT may involve the anastomosis with the IRHV, which is the dominant draining vein of the graft and larger than the RHV, caudal to the IVC stenosis and a significant IVC pressure gradient that results in increased IRHV pressure. In conclusion, it is important to include hepatic vein outflow block in the differential diagnosis when patients who have undergone right hepatic LDLT in which anastomosis of the large IRHV has been performed develop manifestations of liver dysfunction.


Scandinavian Journal of Gastroenterology | 2004

Are the results of surgical treatment of hepatocellular carcinoma poor if the tumor has spontaneously ruptured

Shugo Mizuno; Kentaro Yamagiwa; Tomoko Ogawa; Masami Tabata; Hajime Yokoi; S. Isaji; Shinji Uemoto

Background: The aim of this study was to clarify whether the results of surgical treatment of ruptured hepatocellular carcinoma (HCC) are poorer than the results of surgical treatment of non‐ruptured HCC. Methods: Out of a total of 224 HCC patients, the 6 patients with ruptured HCC were compared with 15 patients with non‐ruptured HCC based on TNM stage IVA and having a Cancer of the Liver Italian Program (CLIP) score of 1 or 2. Results: There were no significant differences in clinical and pathological features between the two groups. The 1‐year and 3‐year overall survival rates were 69.3% and 21.2%, respectively, in the ruptured HCC group and 51.3% and 20.5%, respectively, in the non‐ruptured HCC group. The 1‐year and 3‐year disease‐free survival rates were 33.0% and 0%, respectively, in the ruptured HCC group and 38.9% and 15.6%, respectively, in the non‐ruptured HCC group. The differences in survival rates between these two groups did not reach statistical significance. Conclusion: Hepatic resection as definitive treatment after recovery from the initial insult of the rupture of HCC yields results similar to those obtained by surgical treatment of non‐ruptured HCC at the same tumor stage and with the same degree of liver damage.


Cancer Chemotherapy and Pharmacology | 1994

Surgical treatment of hepatocellular carcinoma

Yoshifumi Kawarada; Fumito Ito; Hiroyuki Sakurai; Kenji Tanigawa; Makoto Iwata; Takazumi Imai; Hajime Yokoi; Takashi Noguchi; Ryuji Mizumoto

The effect of surgical treatment for hepatocellular carcinoma (HCC) was evaluated in 149 resected cases, 83.2% of which were associated with liver cirrhosis. The 3- and 5-year survival rates were 60.1% and 39.4%, respectively. The mortality rate was 4.1%. In patients aged over 70 years, liver cirrhosis was found in 53.3% of cases and the mortality rate was 6.7%. The 3- and 5-year survival rates were 50.8% and 33.9%, respectively. Factors that significantly affected survival for more than 5 years were a tumor size of less than 3 cm, Stage I disease, vp(−), IMo, and diploid type. The 5-year survival rate for patients with a single tumor of 3 cm or less was 54.2%, regardless of the surgical procedure. All 15 patients with a solitary tumor of 2 cm or less (Stage I, small liver tumor) were alive with a 5-year survival rate of 100%. The problem is the treatment of patients with a tumor measuring 3–5 cm in diameter and associated liver cirrhosis, because their prognosis after surgery is the worst. HrS (subsegmentectomy) is the minimal procedure of limited hepatectomy for these cases with postoperative multidisciplinary therapy.

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