Masaru Konishi

Chiba-East National Hospital, Tiba, Chiba, Japan

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Publications (222)594 Total impact

  • 12/2015; 1(1). DOI:10.1186/s40792-014-0007-z
  • World Journal of Surgery 08/2015; DOI:10.1007/s00268-015-3198-y · 2.64 Impact Factor
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    ABSTRACT: The aim of this study was to compare the long-term outcomes and perioperative outcomes of Laparoscopic liver resection (LLR) with those of open liver resection (OLR) for hepatocellular carcinoma (HCC) between well-matched patient groups. HCC patients underwent primary liver resection between 2000 and 2010, were collected from 31 participated institutions in Japan and divided into LLR (n=436) and OLR (n=2969) groups. A one-to-one propensity case-matched analysis was used with covariates of baseline characteristics, including tumor characteristics and surgical procedures of hepatic resections. Long-term and short-term outcomes were compared between the matched two groups. The two groups were well balanced by propensity score matching and 387 patients were matched respectively. There were no significant differences in overall survival and disease-free survival between LLR and OLR. The median blood loss (158 g vs 400 g, p<0.001) was significantly lesser with LLR, and the median postoperative hospital stay (13 days vs 16 days, p<0.001) was significantly shorter for LLR. Complication rate (6.7% vs 13.0%, p=0.003) was significantly lesser in LLR. Compared with OLR, LLR in selected patients with HCC showed similar long-term outcomes, associated with less blood loss, shorter hospital stay, and fewer postoperative complications. This article is protected by copyright. All rights reserved.
    Journal of Hepato-Biliary-Pancreatic Sciences 06/2015; 22(10). DOI:10.1002/jhbp.276 · 2.99 Impact Factor
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    ABSTRACT: To clarify the surgical outcome and long-term prognosis of laparoscopic liver resection (LLR) compared with conventional open liver resection (OLR) in patients with colorectal liver metastases (CRLM). A one-to-two propensity score matching (PSM) analysis was applied. Covariates (P < 0.2) used for PSM estimation included preoperative levels of CEA and CA19-9; primary tumor differentiation; primary pathological lymph node metastasis; number, size, location, and distribution of CRLM; existence of extrahepatic metastasis; extent of hepatic resection; total bilirubin and prothrombin activity levels; and preoperative chemotherapy. Perioperative data and long-term survival were compared. From 2005 to 2010, 1,331 patients with hepatic resection for CRLM were enrolled. By PSM, 171 LLR and 342 OLR patients showed similar preoperative clinical characteristics. Median estimated blood loss (163 g vs 415 g, P < .001) and median postoperative hospital stay (12 days vs 14 days; P < .001) were significantly reduced in the LLR group. Morbidity and mortality were similar. Five-year rates of recurrence-free, overall, and disease-specific survival did not differ significantly. The R0 resection rate was similar. In selected CRLM patients, LLR is strongly associated with lower blood loss and shorter hospital stay and has equivalent long-term survival comparable with OLR. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    Journal of Hepato-Biliary-Pancreatic Sciences 04/2015; 22(10). DOI:10.1002/jhbp.261 · 2.99 Impact Factor
  • Gastroenterology 04/2015; 148(4):S-1182. DOI:10.1016/S0016-5085(15)34035-X · 16.72 Impact Factor
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    ABSTRACT: The patient was a 61-year-old male who was referred to our hospital after dilatation of the main pancreatic duct was detected by screening ultrasonography. Computed tomography revealed a protruding lesion measuring 15 mm in diameter within the main pancreatic duct in the head of the pancreas, and magnetic resonance cholangiopancreatography revealed interruption of the duct at the tumor site. We performed pancreaticoduodenectomy under a suspected diagnosis of invasive ductal carcinoma. Gross examination of the resected specimen showed that the tumor invaginated into the main pancreatic duct, and no mucin was found. Histological examination revealed proliferation of high-grade dysplastic cells in a tubulopapillary growth pattern. Immunohistochemically, cytokeratin 7 expression was detected, but not trypsin expression. Based on these morphological features, we diagnosed the tumor as intraductal tubulopapillary neoplasm (ITPN). We report the case with bibliographic consideration, together with a review of intraductal neoplasms of the pancreas encountered at our institution.
    International surgery 02/2015; 100(2):281-6. DOI:10.9738/INTSURG-D-14-00172.1 · 0.47 Impact Factor
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    ABSTRACT: To clarify the benefit of energy devices such as ultrasonically activated device and bipolar vessel sealing device in liver surgeries. Several studies have suggested the benefit of energy devices in liver transection, while a randomized trial has found no association between their use and surgical outcomes. Patients scheduled to undergo open liver resection were eligible for this multicenter non-blinded randomized study. They were randomized to receive an energy device (experimental group) or not (control group) during liver transection. The primary endpoint was the proportion of patients with intraoperative blood loss >1,000 mL. The primary aim was to show non-inferiority of hepatectomy with energy device to that without energy device. A total of 212 patients were randomized and 211 (105 and 106 in the respective groups) were analyzed. Intraoperative blood loss >1,000 mL occurred in 15.0 % patients with energy device and 20.2 % patients without energy device. The experimental minus control group difference was -5.2 % (95 % confidence interval -13.8 to 3.3 %; non-inferiority test, p = 0.0248). Hepatectomy with energy device resulted in a shorter median liver transection time (63 vs. 84 min; p < 0.001) and a lower rate of postoperative bile leakage (4 vs. 16 %; p = 0.002). The hypothesis that hepatectomy with energy device is not inferior to that without energy device in terms of blood loss has been demonstrated. The use of energy devices during liver surgery is clinically meaningful as it shortens the liver transection time and reduces the incidence of postoperative bile leakage.
    World Journal of Surgery 01/2015; 39(6). DOI:10.1007/s00268-015-2967-y · 2.64 Impact Factor
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    ABSTRACT: A 64-year-old man visited our hospital because of jaundice, and was given a diagnosis of pancreatic head cancer. A preoperative screening examination revealed prolonged prothrombin time (17.7 sec.) and activated partial thromboplastin time (63.1 sec.). The value of factor V was 5%. We found the patient had pancreatic head cancer with ‍congenital factor V deficiency, so we transfused fresh frozen plasma (FFP) preoperatively in order to improve ‍prothrombin time and activated partial thromboplastin time. Under FFP transfusion, we conducted pancreatoduodenectomy successfully. We transfused 4 units of FFP for 4 days postoperatively. There was no serious tendency to hemorrhage during the operation or in the postoperative period.
    Nippon Shokaki Geka Gakkai zasshi 01/2015; 48(7):605-610. DOI:10.5833/jjgs.2014.0208
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    ABSTRACT: Several studies have shown that maintenance of the central venous pressure at a low level during liver surgery is effective for intraoperative management. However, others have suggested that stroke volume variation (SVV) may be a better predictor of fluid responsiveness than central venous pressure. The purpose of this study is to conduct a new type of circulatory management using the FloTrac(TM) system in laparoscopic liver resection and to evaluate specific fluctuations in SVV. Of the laparoscopic liver resections that we performed between March 2012 and December 2013, we used the FloTrac system for intraoperative circulatory management in 21 cases. We analyzed the data, mainly the average value of SVV. The average SVV value during liver transection was 5.2%-24.6% (mean, 17.0%), and 18 cases (86%) exceeded the conventional cut-off value (13%). The average SVV value was 4.3%-18.2% (mean, 9.7%) when pneumoperitoneum was not in effect, whereas it was 7.3% greater on average during liver transection (mean, 17.0%). No perioperative complications developed. The average SVV value during laparoscopic liver transection (mean, 17.0%) exceeded the conventional cut-off value, but in this study, no perioperative complications developed, which enabled safe management. We might be able to manage appropriate fluid control using FloTrac system in patients with laparoscopic liver resection. Therefore, it is necessary to set the target SVV and conduct prospective trials to verify the safety margin for intraoperative management in the future. © 2014 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Wiley Publishing Asia Pty Ltd.
    Asian Journal of Endoscopic Surgery 12/2014; 8(2). DOI:10.1111/ases.12158
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    ABSTRACT: Precise risk assessment for postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD) may be facilitated using imaging modalities. Computed tomography perfusion (CTP) of the pancreas may represent histologic findings. This study aimed to evaluate the utility of CTP data for the risk of POPF after PD, in relation to histologic findings. Twenty patients who underwent preoperative pancreatic CTP measurement using 320-detector row CT before PD were investigated. Clinicopathologic findings, including CTP data, were analyzed to assess the occurrence of POPF. In addition, the correlation between CTP data and histologic findings was evaluated. POPF occurred in 11 cases (grade A, 6; grade B, 5; and grade C, 0). In CTP data, both high arterial flow (AF) and short mean transit time (MTT) were related to POPF occurrence (P = 0.001, P = 0.001). AF was negatively correlated with fibrosis in the pancreatic parenchyma (r = -0.680), whereas MTT was positively correlated with fibrosis (r = 0.725). AF >80 mL/min/100 mL and MTT <16 s showed high sensitivity, specificity, positive predictive value, and negative predictive value (80.0%, 100.0%, 100.0%, and 83.3%, respectively) for the occurrence of POPF. CTP data for the pancreas were found to be correlated with the occurrence of POPF after PD. Alterations in the blood flow to the remnant pancreas may reflect histological changes, including fibrosis in the pancreatic stump, and influence the outcome after PD. CTP may thus facilitate objective and quantitative risk assessment of POPF after PD. Copyright © 2014 Elsevier Inc. All rights reserved.
    Journal of Surgical Research 11/2014; 194(2). DOI:10.1016/j.jss.2014.11.046 · 1.94 Impact Factor
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    ABSTRACT: Although pancreatic consistency is a factor known to have an impact on the occurrence of postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD), it usually is assessed subjectively by the surgeon. Measurement of the elastic modulus (EM), a parameter characterizing the elasticity of a material, may be one approach for achieving objective and quantitative assessment of pancreatic consistency. This study was conducted to investigate the utility of determining the EM of the pancreas. Fifty-nine patients who underwent PD and measurement of the EM of the ex vivo pancreas were investigated. Data for EM were compared with the tactile evaluation made by surgeons, histologic findings, and the occurrence of POPF. The EM of the pancreas was correlated with the tactile evaluation made by the surgeon (soft pancreas, 1.4 ± 2.1 kPa vs hard pancreas, 4.4 ± 5.1 kPa; P < .001). An EM of >3.0 kPa was correlated with histologic findings including increased ratios of azan-Mallory positivity (P = .003) and α-smooth muscle actin positivity (P = .006), a decreased lobular ratio (P = .021), and an increased vessel density (P < .001). Patients with a pancreatic EM of <3.0 kPa had an increased risk of POPF (hazard ratio, 9.333; P = .002). Assessment of the EM of the resected pancreas reflects the tactile evaluation made by the surgeon and histological degree of pancreatic fibrosis, and is correlated with the occurrence of POPF after PD. Copyright © 2014 Elsevier Inc. All rights reserved.
    Surgery 11/2014; 156(5):1204-11. DOI:10.1016/j.surg.2014.05.015 · 3.38 Impact Factor
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    ABSTRACT: Background: The international consensus guidelines for the management of intraductal papillary mucinous neoplasm (IPMN) of the pancreas were revised in 2012 Tanaka (Pancreatology 12(3):183-197, 2012), making the indications for operation less aggressive. Therefore, the number of branch duct-type IPMN (BD-IPMN) patients requiring follow-up care is expected to increase in the future. Methods: The aim of this study was to identify risk factors for malignancy in BD-IPMN patients during the follow-up period. This study included 47 BD-IPMN patients without a mural nodule (MN) at the time of initial diagnosis and who subsequently underwent resection after a follow-up period of more than 3 months. Data for the patients were reviewed retrospectively, and the clinicopathological factors were investigated. Results: In a univariate analysis, age (≧ 65 years), an increase in the main pancreatic duct (MPD) diameter, the MPD diameter at resection (≧ 5 mm), and the occurrence of MN were significantly associated with malignancy. The occurrence of MN was the only significant factor in a multivariate analysis. In addition, 7 of the 17 patients (41.2 %) who only exhibited an increase in the cyst diameter during the follow-up period were diagnosed as having malignancies. All 6 patients who exhibited an increase in the cyst diameter of 100 % or more were diagnosed as having carcinoma. Conclusions: During the follow-up period, the incidence of malignancy was higher among patients with BD-IPMNs and the occurrence of MN, an increase in the MPD diameter, or an increase ratio of 100 % or more in cyst diameter than the others; resection was recommended for these patients.
    World Journal of Surgery 10/2014; 39(1). DOI:10.1007/s00268-014-2789-3 · 2.64 Impact Factor
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    ABSTRACT: Background: The treatment strategy for adenocarcinoma of the esophagogastric junction (AEG) remains controversial. In the present study, the recurrence pattern of AEGs according to Siewert's classification after radical resection was reviewed, and predictive factors of recurrence were examined. Patients and methods: We retrospectively analyzed the clinical data of 127 consecutive patients with Siewert type I, II, and III AEGs who underwent curative resection (R0) without perioperative chemotherapy at the National Cancer Center Hospital East between January 1993 and November 2006. Results: The median follow-up period was 48.9 (range=1.5-179) months. The recurrence rates of type I, II, and III tumors were 57.1%, 44.4%, and 41.0%, respectively. The most frequent relapse site was lymphogenous in type I, hematogenous in type II, and disseminative in type III tumors. The median time-to-recurrence after surgery was 12.6 months in type I, 12.5 months in type II, and 12.7 months in type III disease, with no significant difference. Multivariate analysis revealed that mediastinal lymph node metastasis (p=0.005) (hazard ratio=2.954, 95% Confidence Interval=1.38-6.31) was a significant and independent prognostic indicator for poor recurrence-free survival. The recurrence rate in patients with mediastinal lymph node metastasis at the time of surgery was 100%. Conclusion: The recurrence pattern of AEGs differed according to Siewert's classification. Its tendency should be understood in order to determine the optimal surgical approach. Mediastinal lymph node dissection may be effective for local control, but may not significantly improve prognosis. When mediastinal lymph node metastasis is suspected, perioperative chemotherapy may be recommended.
    Anticancer research 08/2014; 34(8):4391-7. · 1.83 Impact Factor
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    ABSTRACT: Background: The prognostic significance of bile duct tumor thrombus (BDTT) in hepatocellular carcinoma (HCC) is unclear and the usefulness of resection for HCC with BDTT is still controversial. The aim of the present study was to evaluate the impact of BDTT on prognosis in HCC and to determine whether resection of HCC with BDTT was useful. Patients and methods: Out of 820 HCC patients who underwent hepatic resection from 1992 to 2012, 13 HCC patients (1.6%) had macroscopic BDTT. The results of resection for HCC patients with BDTT and the prognostic significance of BDTT were evaluated. Prognoses were also compared according to treatment in patients who had HCC with BDTT. Results: The overall 1-, 3- and 5-year survival rates after resection were 92%, 77% and 48%, respectively, for HCC patients with BDTT, and 88%, 67%, and 52%, respectively, for HCC patients without BDTT; there were no significant differences (p=0.833). In all HCC patients after resection, the unadjusted hazard ratio of the presence of BDTT was 1.08 (95%CI=0.49-2.05; p=0.835) and when adjusted for other significant prognostic factors, the hazard ratio of the presence of BDTT was 0.98 (95%CI=0.42-1.98; p=0.958). The overall 1-, 3- and 5-year survival rates were 14%, 5% and 0%, respectively, for 25 HCC patients with BDTT after other initial treatments. Conclusion: Bile duct tumor thrombus was not a prognostic factor in patients with resected HCC. In HCC with BDTT, surgical treatment is recommended whenever possible because only resected patients achieved long-term survival.
    Anticancer research 08/2014; 34(8):4367-72. · 1.83 Impact Factor
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    ABSTRACT: Background: Neural invasion is a characteristic pattern of invasion and an important prognostic factor for invasive ductal carcinoma (IDC) of the pancreas. M2 macrophages have reportedly been associated with poor prognosis in various cancers. The aim of the present study was to investigate the prognostic impact of M2 macrophages at extrapancreatic nerve plexus invasion (plx-inv) of pancreatic IDC. Methods: Participants comprised 170 patients who underwent curative pancreaticoduodenectomy for pancreatic IDC. Immunohistochemical examination of surgical specimens was performed by using CD204 as an M2 macrophage marker, and the area of immunopositive cells was calculated automatically. Prognostic analyses of clinicopathological factors including CD204-positive cells at plx-inv were performed. Results: Plx-inv was observed in 91 patients (53.5%). Forty-eight patients showed a high percentage of CD204-positive cell area at plx-inv (plx-inv CD204%(high)). Plx-inv CD204%(high) was an independent predictor of poor outcomes for overall survival (OS) (P<0.001) and disease-free survival (DFS) (P<0.001). Patients with plx-inv CD204%(high) showed a shorter time to peritoneal dissemination (P<0.001) and locoregonal recurrence (P<0.001). In patients who underwent adjuvant chemotherapy, plx-inv CD204%(high) was correlated with shorter OS (P=0.011) and DFS (P=0.038) in multivariate analysis. Conclusions: Plx-inv CD204%(high) was associated with shortened OS and DFS and early recurrence in the peritoneal cavity and locoregional space. The prognostic value of plx-inv CD204%(high) was also applicable to patients who received adjuvant chemotherapy. High accumulation of M2 macrophages at plx-inv represents an important predictor of poor prognosis.
    European journal of cancer (Oxford, England: 1990) 05/2014; 50(11). DOI:10.1016/j.ejca.2014.04.010 · 5.42 Impact Factor
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    ABSTRACT: Duodenal cancer excluding Vater's papilla cancer is a relatively rare disease entity; therefore, the most appropriate operative methods depending on the tumor condition, such as the tumor site and/or depth of invasion, still remain unclear. The aim of this study is to determine an appropriate operative method and an appropriate extent of lymph node dissection depending on tumor site or tumor invasion depth. Data of a total of 35 patients with duodenal cancer who underwent resectional surgery with curative intent were reviewed retrospectively, and the clinicopathological factors and survival outcomes were investigated. Overall 5-year survival rates of all resected cases were 63.0% (median survival: 9.1 years). Multivariate analysis identified histological G3/4 (P = 0.002) and presence of lymph node metastasis (P = 0.004) as independent adverse prognostic factors. Of the 35 patients, 11 (31.4%) had lymph node metastasis. In all patients with the tumor invasion depth within limited to the mucosa or submucosa (T1a or T1b), lymph node metastasis was absent (0/15 patients). T2/3/4 tumor (P < 0.001) and G3/4 (P = 0.021) were identified as predictors of the presence of lymph node metastasis. Four (11.4%) of the 35 patients had metastasis in the infrapyloric node. Limited resection is sufficient for patients with T1a tumor. In the case of T1b tumor, limited resection or pancreatoduodenectomy may be selected after performing pancreaticoduodenal node biopsy as sentinel lymph node biopsy. For patients with T2-4 tumor, pancreatoduodenectomy or substomach preserving pancreatoduodenectomy (excepting Pylorus-preserving pancreatoduodenectomy) with regional lymph node dissection should be performed.
    Japanese Journal of Clinical Oncology 01/2014; 44(3). DOI:10.1093/jjco/hyt213 · 2.02 Impact Factor
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    ABSTRACT: A 74-year-old woman presented with obstructive jaundice and was referred to our hospital, as perihilar cholangiocarcinoma was suspected. We performed extended right hepatectomy with regional lymphadenectomy and resection of the extrahepatic bile duct and portal vein. Pathological findings revealed neuroendocrine cell carcinoma G3 (World Health Organization classification, 2010). No other lesions were detected by intraoperative findings or preoperative examinations such as gastroenterological endoscopy, computed tomography, and magnetic resonance imaging ; therefore, primary hepatic neuroendocrine carcinoma was diagnosed. The patient showed recurrence with multiple liver metastases four months after the operation, and now receives chemotherapy.Primary neuroendocrine tumor of the liver is an extremely rare disease. Here, we report a rare case of primary hepatic neuroendocrine cell carcinoma and review the current literature.
    Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association) 01/2014; 75(11):3135-3140. DOI:10.3919/jjsa.75.3135

Publication Stats

4k Citations
594.00 Total Impact Points


  • 1994–2015
    • Chiba-East National Hospital
      Tiba, Chiba, Japan
  • 1997–2014
    • National Cancer Center, Japan
      • • Center for Cancer Control and Information Services
      • • National Cancer Center Research Institute
      Edo, Tōkyō, Japan
    • Jichi Medical University
      • Department of Pathology
      Totigi, Tochigi, Japan
  • 2004
    • University of Tsukuba
      Tsukuba, Ibaraki, Japan
  • 2001–2002
    • National Cancer Research Institute
      Londinium, England, United Kingdom
  • 2000
    • Tokyo Medical and Dental University
      Edo, Tōkyō, Japan
  • 1995–1996
    • Tokyo Metropolitan Institute of Medical Science
      Edo, Tōkyō, Japan