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Featured researches published by Yukihiro Koike.


Cancer | 2005

Percutaneous radiofrequency ablation for hepatocellular carcinoma. An analysis of 1000 cases.

Ryosuke Tateishi; Shuichiro Shiina; Takuma Teratani; Shuntaro Obi; Shinpei Sato; Yukihiro Koike; Tomonori Fujishima; Haruhiko Yoshida; Takao Kawabe; Masao Omata

Radiofrequency ablation (RFA) was introduced recently as a therapeutic modality for hepatocellular carcinoma (HCC), an alternative to percutaneous ethanol injection therapy (PEIT), which is coming into use worldwide. Previously reported treatment efficacy and complication rates have varied considerably.


Annals of Internal Medicine | 2003

Interferon Therapy after Tumor Ablation Improves Prognosis in Patients with Hepatocellular Carcinoma Associated with Hepatitis C Virus

Yasushi Shiratori; Shuichiro Shiina; Takuma Teratani; Masatoshi Imamura; Shuntaro Obi; Shinpei Sato; Yukihiro Koike; Haruhiko Yoshida; Masao Omata

Context Hepatocellular carcinoma often follows hepatitis C virus infection. Currently available treatments for hepatocellular carcinoma are unsatisfactory. Percutaneous ethanol injection therapy into tumor nodules shows some promise, but recurrence rates are high. Contribution In a carefully selected group of 74 patients with multicentric hepatocellular carcinoma, mild hepatitis C, and mild cirrhosis, patients randomly assigned to receive interferon in addition to ethanol injections showed improved survival at 5 and 7 years, particularly among patients with a sustained virologic response. Cautions Combined treatment of multicentric hepatocellular carcinoma offers the possibility of enhanced survival for carefully selected patients; this study is small, however, and enrolled only patients with low virus levels and mild cirrhosis. The Editors Chronic hepatitis C virus (HCV) infection is a common, frequently asymptomatic disease. Despite the clinically quiescent course of HCV infection, it may slowly progress to cirrhosis and, eventually, to hepatocellular carcinoma (1, 2). Cirrhosis is a major risk factor for the development of hepatocellular carcinoma (3, 4), and 70% to 80% of patients with hepatocellular carcinoma in Japan have HCV infection (5). Current strategies for treating hepatocellular carcinoma include surgical resection, transarterial embolization, percutaneous ethanol injection therapy, radiofrequency wave ablation, and chemotherapy (6-9). Recent studies have shown that percutaneous ethanol injection therapy is effective for hepatocellular carcinoma when the tumors are small (<3 to 5 cm in diameter) and limited in number; survival rates are similar to those obtained with surgery (10-12). Five-year survival rates, however, are poor (30% to 60% for both hepatectomy and percutaneous ethanol injection therapy). Poor prognosis may be the result of the high incidence of tumor recurrence; the cumulative recurrence rate at 5 years is 60% to 100% (10-13). Several studies have evaluated the factors that contribute to the recurrence of hepatocellular carcinoma (12, 13). Occasionally, early recurrence develops adjacent to the treated lesion (local recurrence, 6% to 33% depending on tumor size) (14), but most tumors (80% to 90%) recur at different sites (15). Because hepatocellular carcinoma recurrence and decompensation of underlying liver disease are major problems after medical or surgical treatment, liver transplantation is another option for treating small, unresectable hepatocellular carcinomas in patients with cirrhosis. Studies report 5-year survival rates as high as 75% with liver transplantation (16-18). Interferon therapy has beneficial effects in chronic HCV infection (19, 20). In long-term follow-up studies, sustained virologic responders have remained in remission with normal liver function and improved histologic features of inflammation; in some of these responders, fibrosis even regresses (21, 22). Recently, the frequency of hepatocellular carcinoma in patients receiving interferon therapy has substantially decreased, especially in patients with sustained virologic and biochemical responses (23-25). This decreased frequency has occurred even in patients with cirrhosis (25, 26). Our study evaluated whether complete ablation of neoplastic nodules and administration of antiviral therapy could increase survival rates. Methods Study Design Our prospective study was designed by an eight-member committee in December 1992. The Ethics Committee of the University of Tokyo approved the study. We obtained informed consent from each patient in accordance with the Helsinki declaration. Patients with compensated cirrhosis, three or fewer nodules of hepatocellular carcinoma, and low HCV RNA loads were recruited after complete ablation of the lesions. Eligibility Criteria Inclusion Criteria Hepatitis C virus infection was diagnosed on the basis of identification of anti-HCV antibody using the passive hemagglutination test (Dinabbot, Tokyo, Japan) or enzyme-linked immunosorbent assay (ELISA; Ortho Diagnostic Systems, Tokyo, Japan). Hepatitis C virus RNA was identified by reverse transcriptase polymerase chain reaction (RT-PCR). The serum HCV RNA level was measured by competitive reverse transcriptase (CRT)-PCR according to the method of Kato and colleagues (27); HCV genotype was determined by the method of Okamoto and colleagues (28). Hepatocellular carcinoma was suspected on the basis of several imaging methods, including abdominal ultrasonography, dynamic computed tomography (CT), magnetic resonance imaging (MRI), and arteriography. We confirmed the diagnosis by histologic examination of tumor biopsy specimens obtained from all patients. Evaluation was based on the criteria of the International Working Party (29). In addition, we obtained and evaluated biopsy specimens from non-neoplastic lesions according to the methods of Desmet and colleagues (30). Hepatocellular carcinoma was treated with percutaneous ethanol injection therapy (7, 8, 10). Real-time linear-array scanners were used with 3.5-MHz transducers for the sonographic guidance of needles [21-gauge with a 15-cm or 20-cm needle; Hanako, Tokyo, Japan] into the tumors. Two to 10 mL of 99.5% ethanol was injected into each lesion. Ethanol injection was repeated several times at different sessions. Complete destruction of the nodules was confirmed on dynamic CT 1 month after ethanol injection according to the following criteria: 1) The destructive area was larger than the area of the tumor nodule shown on pretreatment dynamic CT and 2) dynamic CT showed no early-phase contrast enhancement of nodules (7, 8, 10). Inclusion criteria were as follows: 1) hepatocellular carcinoma with three or fewer lesions [verified by histologic examination] and dynamic CTconfirmed complete ablation of hepatocellular carcinoma lesions by percutaneous ethanol injection therapy, 2) detection of HCV RNA by RT-PCR and an HCV RNA load of 2 106 copies/mL or less by CRT-PCR (the cutoff value was based on unpublished data indicating that interferon treatment was effective in patients with HCV RNA loads of 105 copies/50 L of serum by CRT-PCR [27]], 3) platelet count of 50 109 cells/L, 4) leukocyte count of 3 109 cells/L or greater, 5) compensated cirrhosis in ChildPugh stage A, 6) age younger than 70 years, 7) no previous treatment with interferon, and 8) submission of informed consent. Exclusion Criteria Exclusion criteria were as follows: 1) liver diseases due to other causes, such as hepatitis B or primary biliary cirrhosis; 2) HCV RNA load of 2 106 copies/mL or greater by CRT-PCR; 3) severe comorbid diseases, such as heart disease, lung disease, or diabetes mellitus; 4) decompensated cirrhosis in ChildPugh stage B or C; and 5) failure to obtain informed consent. Randomization Patients who enrolled in the study were randomly assigned in a 2:1 ratio to the interferon group or the control group by the controller. We assigned patients to the treatment group or control group by using a randomization list. Interferon Therapy and Follow-up of Patients Interferon Therapy We started interferon therapy with natural interferon- (Sumitomo Pharmaceuticals, Tokyo, Japan) 2 to 3 months after tumor ablation was confirmed. Patients received 6 million U of interferon by intramuscular injection three times weekly for 48 weeks as outpatients. If patients could not tolerate this dose, the interferon dose was reduced to 3 million U. If HCV RNA in serum was still detected by RT-PCR (detection limit, 102 copies/mL) after 24 weeks of interferon therapy and serum alanine aminotransferase (ALT) levels were higher than pretreatment ALT levels, therapy was discontinued. Criteria for Interferon Response We defined the efficacy of interferon therapy virologically and biochemically. Patients who were negative for HCV RNA (as determined by RT-PCR; detection limit, 102 copies/mL) more than 6 months after the completion of interferon therapy were classified as showing a sustained virologic response. Patients with persistently normal ALT levels after the completion of interferon therapy were classified as showing a sustained biochemical response; patients with abnormal ALT levels were classified as showing a nonsustained biochemical response. Follow-up Patients attended a monthly medical consultation at the University of Tokyo Hospital outpatient clinic. Blood biochemical measures, including -fetoprotein (AFP) tumor markers, were measured every 1 to 2 months; ultrasonography was performed every 2 to 3 months; and dynamic CT was performed every 6 months. Recurrence of hepatocellular carcinoma was detected by the finding of abnormal nodules with low or high echogenic appearance on abdominal ultrasonography or by the finding of abnormal density on dynamic CT. The diagnosis was confirmed histologically through ultrasonography-guided fine-needle biopsy of the tumor. Recurrent nodules were divided into two categories [14, 15]: 1) local recurrence, in which the nodule appeared adjacent to the previously treated nodules, suggesting that residual tumor cells had not been completely ablated by percutaneous ethanol injection therapy, or 2) new foci developing at a distant site. New foci of hepatocellular carcinoma, as well as local recurrent nodules at tumor, node, metastasis (TNM) stage I, II, and III, were mainly treated by a second course of percutaneous ethanol injection therapy; local recurrent nodules at TNM stage IV were treated with transarterial chemoembolization or chemotherapy. New development of hepatocellular carcinoma and survival of the patients (tumor recurrence rate and survival rate) were analyzed in relation to the time interval after initial treatment. Statistical Analysis When estimating the sample size, we assumed that 5-year survival in the control group would be 40% according to the data of our previous unpublished study. We predicted that 5-year survival would be increased by 35% as a result of treatment


Gut | 2005

Proposal of a new prognostic model for hepatocellular carcinoma: an analysis of 403 patients

R. Tateishi; Haruhiko Yoshida; Shuichiro Shiina; H Imamura; Kiyoshi Hasegawa; Takuma Teratani; Shuntaro Obi; Shinpei Sato; Yukihiro Koike; Tomonori Fujishima; Masatoshi Makuuchi; Masao Omata

Background: The prognosis of hepatocellular carcinoma (HCC) is highly dependent on tumour extension and liver function. Recently, two new prognostic scoring systems—the CLIP score, developed by Italian investigators and the BCLC score, developed in Barcelona—have been widely used to assess prognosis in patients presenting with hepatocellular carcinoma. Each system has its own relative limitations. Aims: To create a new prognostic scoring system which is simple, easy to calculate, and suitable for estimating prognosis during radical treatment of early HCC. Methods: A total of 403 consecutive patients with HCC treated by percutaneous ablation at the Department of Gastroenterology, University of Tokyo Hospital, between 1990 and 1997 were used as the training sample to identify prognostic factors for our patients and used to develop the Tokyo score. As a testing sample, 203 independent patients who underwent hepatectomy at the Department of Hepato-Biliary-Pancreatic Surgery were studied. Prognostic factors were analysed by univariate and multivariate Cox proportional hazard regression. Results: The Tokyo score consists of four factors: serum albumin, bilirubin, and size and number of tumours. Five year survival was 78.7%, 62.1%, 40.0%, 27.7%, and 14.3% for Tokyo scores 0, 1, 2, 3, and 4–6, respectively. The discriminatory ability of the Tokyo score was internally validated by bootstrap methods. The Tokyo score, CLIP score, and BCLC staging were compared by Akaike information criterion and Harrell’s c index among training and testing samples. In the testing sample, the predictive ability of the Tokyo score was equal to CLIP and better than BCLC staging. Conclusions: The Tokyo score is a simple system which provides good prediction of prognosis for Japanese patients with HCC requiring radical therapy.


Oncology | 2002

Nonsurgical treatment of hepatocellular carcinoma: From percutaneous ethanol injection therapy and percutaneous microwave coagulation therapy to radiofrequency ablation

Shuichiro Shiina; Takuma Teratani; Shuntaro Obi; Keisuke Hamamura; Yukihiro Koike; Masao Omata

Treatment of hepatocellular carcinoma (HCC) is different from that of other solid tumors, in that surgery plays a limited role while nonsurgical therapies are very instrumental. At our institute, 90% of previously untreated patients have received image-guided percutaneous tumor ablations, such as percutaneous ethanol injection therapy (PEIT), percutaneous microwave coagulation therapy (PMCT) and radiofrequency ablation (RFA). We performed PEIT in 756 patients with HCC. Their survival rates were 89% at 1 year, 64% at 3 years, 39% at 5 years, and 18% at 10 years. With PMCT, survival rates of 122 new patients with HCC were 90% at 1 year, 87% at 2 years, and 68% at 3 years. We performed RFA in 324 patients. RFA required fewer treatment sessions and a shorter hospital stay than PEIT or PMCT to achieve complete necrosis of the lesions. By virtue of their local curability, minimal effect on liver function, and easy repeatability for recurrence, image-guided percutaneous tumor ablations, especially RFA, will be increasingly important in the treatment of HCC.


Hepatology | 2004

Vitamin K2 inhibits the growth and invasiveness of hepatocellular carcinoma cells via protein kinase A activation.

Motoyuki Otsuka; Naoya Kato; Run-Xuan Shao; Yujin Hoshida; Hideaki Ijichi; Yukihiro Koike; Hiroyoshi Taniguchi; Masaru Moriyama; Yasushi Shiratori; Takao Kawabe; Masao Omata

Heatocellular carcinoma (HCC) is a common human malignancy. Its high mortality rate is mainly a result of high intrahepatic recurrence and portal venous invasion (PVI). We previously reported that the development of PVI is related to levels of des‐gamma‐carboxy prothrombin (DCP), a serum protein that increases at a notably higher rate in patients with HCC. Because DCP is produced by a vitamin K shortage, we examined the biological effects of extrinsic supplementation of vitamin K2 in HCC cells in vitro and in vivo. Consequently, vitamin K2 inhibits the growth and invasion of HCC cells through the activation of protein kinase A, which modulates the activities of several transcriptional factors and inhibits the small GTPase Rho, independent of suppression of DCP. In addition, administration of vitamin K2 to nude mice inoculated with liver tumor cells reduced both tumor growth and body weight loss. In conclusion, similar to an acyclic retinoid—which was previously reported to prevent the recurrence of HCC—vitamin K2, another lipid‐soluble vitamin, may be a promising therapeutic means for the management of HCC. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270‐9139/suppmat/index.html). (HEPATOLOGY 2004;40:243–251.)


Hepatology | 2011

Effect of vitamin K2 on the recurrence of hepatocellular carcinoma

Haruhiko Yoshida; Yasushi Shiratori; Masatoshi Kudo; Shuichiro Shiina; Toshihiko Mizuta; Masamichi Kojiro; Kyosuke Yamamoto; Yukihiro Koike; Kenichi Saito; Nozomu Koyanagi; Takao Kawabe; Seiji Kawazoe; Haruhiko Kobashi; Hiroshi Kasugai; Yukio Osaki; Yasuyuki Araki; Namiki Izumi; Hiroko Oka; Kunihiko Tsuji; Joji Toyota; Toshihito Seki; Toshiya Osawa; Naohiko Masaki; Masao Ichinose; Masataka Seike; Akihisa Ishikawa; Yoshiyuki Ueno; Kazumi Tagawa; Ryoko Kuromatsu; Shotaro Sakisaka

Hepatocellular carcinoma (HCC) is characterized by frequent recurrence, even after curative treatment. Vitamin K2, which has been reported to reduce HCC development, may be effective in preventing HCC recurrence. Patients who underwent curative ablation or resection of HCC were randomly assigned to receive placebo, 45 mg/day, or 90 mg/day vitamin K2 in double‐blind fashion. HCC recurrence was surveyed every 12 weeks with dynamic computed tomography/magnetic resonance imaging, with HCC‐specific tumor markers monitored every 4 weeks. The primary aim was to confirm the superiority of active drug to placebo concerning disease‐free survival (DFS), and the secondary aim was to evaluate dose‐response relationship. Disease occurrence and death from any cause were treated as events. Hazard ratios (HRs) for disease occurrence and death were calculated using a Cox proportional hazards model. Enrollment was commenced in March 2004. DFS was assessed in 548 patients, including 181 in the placebo group, 182 in the 45‐mg/day group, and 185 in the 90‐mg/day group. Disease occurrence or death was diagnosed in 58, 52, and 76 patients in the respective groups. The second interim analysis indicated that vitamin K2 did not prevent disease occurrence or death, with an HR of 1.150 (95% confidence interval: 0.843‐1.570, one‐sided; P = 0.811) between the placebo and combined active‐drug groups, and the study was discontinued in March 2007.


Liver International | 2004

Evaluation of transcatheter arterial embolization prior to percutaneous tumor ablation in patients with hepatocellular carcinoma: a randomized controlled trial.

Masatoshi Akamatsu; Haruhiko Yoshida; Shuntaro Obi; Shinpei Sato; Yukihiro Koike; Tomonori Fujishima; Ryosuke Tateishi; Masatoshi Imamura; Keisuke Hamamura; Takuma Teratani; Shuichiro Shiina; Takashi Ishikawa; Masao Omata

Abstract: Background: Transcatheter arterial embolization (TAE) may reduce the risk of hepatocellular carcinoma (HCC) recurrence when performed before percutaneous tumor ablation (PTA), either percutaneous ethanol injection therapy (PEIT) or radiofrequency ablation (RFA). We conducted a randomized, controlled trial comparing the use of TAE combined with percutaneous ethanol injection therapy (TAE/PEIT) to the use of PEIT only to assess the effects on HCC recurrence and survival. We continued the study after the introduction of RFA and compared TAE combined with RFA (TAE/RFA) with RFA only.


Journal of Gastroenterology | 2003

Congenital absence of portal vein with multiple hyperplastic nodular lesions in the liver

Yasuo Tanaka; Masaki Takayanagi; Yasushi Shiratori; Yasuo Imai; Shuntaro Obi; Ryosuke Tateishi; Miho Kanda; Tomonori Fujishima; Masatoshi Akamatsu; Yukihiro Koike; Keisuke Hamamura; Takuma Teratani; Takashi Ishikawa; Shuichiro Shiina; Masamichi Kojiro; Masao Omata

Congenital absence of the portal vein is an extremely rare anomaly, in which enteric blood bypasses the liver and drains into the inferior vena cava. A 16-year-old girl was referred to our hospital presenting with liver tumor. Although she had suffered from galactosemia soon after birth, the galactosemia had improved spontaneously 1 year later. Between the ages of 8 and 12 years, chronic hepatitis with a mild elevation of aspartate transaminase (AST) and alanine transaminase (ALT) was observed, but liver tumor had not been detected on computed tomography (CT) in regular medical examinations. However, at age 16, liver tumors, 10 cm in diameter, were found. Abdominal angiography indicated complete absence of the portal vein, suggesting that enteric blood was bypassing the liver and draining into the inferior vena cava. In biopsy specimens obtained under ultrasonographic guidance, liver tumors were confirmed histologically as hyperplastic nodules. In addition to this case report, the clinical features of 25 reported cases of congenital absence of the portal vein are reviewed.


Liver International | 2012

Percutaneous ethanol injection for hepatocellular carcinoma: 20‐year outcome and prognostic factors

Shuichiro Shiina; Ryosuke Tateishi; Masatoshi Imamura; Takuma Teratani; Yukihiro Koike; Shinpei Sato; Shuntaro Obi; Fumihiko Kanai; Naoya Kato; Haruhiko Yoshida; Masao Omata; Kazuhiko Koike

Ethanol injection is the best‐known image‐guided percutaneous ablation for hepatocellular carcinoma (HCC) and a well‐tolerated, inexpensive procedure with few adverse effects. However, there have been few reports on its long‐term results.


European Journal of Ultrasound | 2001

Percutaneous ethanol injection therapy for liver tumors

Shuichiro Shiina; Takuma Teratani; Shuntaro Obi; Keisuke Hamamura; Yukihiro Koike; Masao Omata

Percutaneous ethanol injection therapy (PEIT) has been widely practiced in the treatment of liver tumors, especially of hepatocellular carcinoma (HCC). Histopathologic examinations, findings in imaging modalities and serum tumor marker levels have shown a remarkable anticancer effect of this procedure. In addition, PEIT has achieved considerably high long-term survival rates. For small HCC, PEIT has been generally accepted as an alternative to surgery. Here we will describe PEIT from the viewpoints of patient selection, technique, various evaluation procedures of efficacy, long-term results, side effects and complications, and relationship with other therapies.

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