Hiroyuki Nitta

Iwate Medical University, Morioka, Iwate, Japan

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Publications (79)120.41 Total impact

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    ABSTRACT: Early on, laparoscopic liver resection (LLR) was limited to partial resection, but major LLR is no longer rare. A difficulty scoring system is required to guide surgeons in advancing from simple to highly technical laparoscopic resections. Subjects were 90 patients who had undergone pure LLR at three medical institutions (30 patients/institution) from January 2011 to April 2014. Surgical difficulty was assessed by the operator using an index of 1-10 with the following divisions: 1-3 low difficulty, 4-6 intermediate difficulty, and 7-10 high difficulty. Weighted kappa statistic was used to calculate the concordance between the operators' and reviewers' (expert surgeon) difficulty index. Inter-rater agreement (weighted kappa statistic) between the operators' and reviewers' assessments was 0.89 with the three-level difficulty index and 0.80 with the 10-level difficulty index. A 10-level difficulty index by linear modeling based on clinical information revealed a weighted kappa statistic of 0.72 and that scored by the extent of liver resection, tumor location, tumor size, liver function, and tumor proximity to major vessels revealed a weighted kappa statistic of 0.68. We proposed a new scoring system to predict difficulty of various LLRs preoperatively. The calculated score well reflected difficulty.
    Journal of Hepato-Biliary-Pancreatic Sciences. 10/2014; 21(10).
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    Annals of Surgery 09/2014; · 6.33 Impact Factor
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    ABSTRACT: Postoperative hyperglycemia is associated with infectious complications after various types of surgery. Our objective was to determine whether postoperative blood glucose levels up to 1 week after highly invasive esophageal cancer surgery are associated with the incidence of postoperative infections (POIs).
    Journal of Gastrointestinal Surgery 07/2014; · 2.36 Impact Factor
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    ABSTRACT: Panitumumab was approved in June 2010 for use in the treatment of unresectable advanced/recurrent colorectal cancer. Here, we report outcomes and adverse events of panitumumab combination therapy or single-agent chemotherapy for K-ras wild-type unresectable or recurrent colorectal cancers. Our study focused on first-line treatments. The study involved 18 patients who started receiving panitumumab in October 2010. Nine patients received panitumumab as a first-line treatment; 4, as a second-line treatment; and 5, as a third-line or subsequent treatment. The overall response rate was 27.8%. Among the patients who received panitumumab as a first-line treatment, the response rate was 55.6%. Grade 1 and 2 skin disorders were common adverse events. Grade 2 interstitial pneumonia was observed in 1 patient(5.6%). Grade 3 or higher events comprised peripheral neuropathy in 1 patient(5.6%)and neutropenia in another patient(5.6%). The treatment was beneficial, and metastatic foci were resected in 3 patients. In this study, the only adverse events of Grade 3 or higher were 1 case each of peripheral neuropathy and neutropenia. Accordingly, adequate control seemed possible. The specific line of treatment that panitumumab should belong to remains controversial. However, active initiation as first-line treatment should be considered for cases in which resection of metastatic foci can be expected from tumor reductions due to panitumumab.
    Gan to kagaku ryoho. Cancer & chemotherapy 06/2014; 41(6):731-735.
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    ABSTRACT: Background The important point in safely performing laparoscopic hepatectomy (LH) is to control bleeding. The aims of this study were: (i) to assess the bleeding reduction effect by occlusion of the hepatic artery in LH; and (ii) to evaluate the risk of carbon dioxide (CO2) gas embolism (GE) in the case of high pneumoperitoneum (PP).Methods Nine piglets underwent laparoscopic left medial lobe and left lateral lobe resection, receiving either occlusion of the hepatic artery (hepatic artery clamping group: HACG, n = 9) or no occlusion (hepatic artery declamping group: HADCG, n = 9) using a PP of 15 mmHg. In addition, we observed changes in hemodynamics induced by PP. The state of GE was observed using transesophageal echocardiography (TEE) during LH (n = 8). GE was graded as grade 0 (none), grade 1 (minor), and grade 2 (major).ResultsThe HACG had significantly less bleeding compared to the HADCG (P < 0.01). During LH, four animals showed grade 1 (37.5%) and one animal showed grade 2 (12.5%) GE at 15 mmHg. At 20 mmHg, all animals showed grade 2 (100%) GE.Conclusion The occlusion of the hepatic artery in LH reduces blood loss. The control of bleeding from the hepatic vein is feasible with a high PP, but there is a possibility of GE.
    Journal of Hepato-Biliary-Pancreatic Sciences. 05/2014;
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    ABSTRACT: We herein report a case of single-port laparoscopic and endoscopic cooperative surgery (LECS) for a gastric gastrointestinal stromal tumor (GIST). A 75-year-old female with an endoluminal GIST located near the esophagogastric junction underwent LECS. Both the mucosal and submucosal layers around the tumor were circumferentially dissected using endoscopic submucosal dissection via intraluminal endoscopy. The endoluminal GIST was exteriorized to the abdominal cavity. The tumor and the edge of the incision line were closed using an endoscopic linear stapler. The LECS was successfully accomplished without the need for any skin incisions or additional ports. The length of the operation was 120 min and blood loss was 5 ml. Oral intake was resumed on the second day and the length of hospital stay was 5 days. No complications were noted and the patient had an excellent cosmetic result. In our experience, single-port LECS is feasible and safe for gastric GIST when performed by a surgeon experienced in laparoscopic and gastric surgery.
    Surgery Today 03/2014; · 0.96 Impact Factor
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    ABSTRACT: The aim of this study was to evaluate the relative contribution of serum adipokines and adipokines from the patient's omentum-derived adipocytes (PODAs) and visceral adipose tissue (VAT) of Japanese patients with severe obesity. Secondarily, we analyzed patients' metabolic changes after laparoscopic sleeve gastrectomy (LSG.). Twenty-three LSG patients and 23 non-obese patients undergoing elective abdominal surgery were enrolled. The levels of adipokines in the serum and the PODAs were measured. The clinical and metabolic data were evaluated at 6 months after LSG. The mean serum leptin levels and the mean serum PAI-1 levels were significantly greater (p < 0.001) and the mean adiponectin levels were significantly lower in the LSG group (p = 0.006). In the measurements of the PODAs, the mean leptin levels (p < 0.001) were significantly greater and the mean adiponectin levels (p < 0.001) were significantly lower in the LSG group. The mean BMI (- 12 kg/m(2), p < 0.001) and mean VAT (- 135.5 cm(2), p = 0.001) were significantly decreased after LSG. In nine patients with type 2 diabetes mellitus, the reduction in VAT correlated with the change in high-sensitivity C-reactive protein (p = 0.006) and the homeostasis model of assessment of insulin resistance (p = 0.001). After 6 months, LSG markedly improved most obesity-related comorbidities. Our results suggest that LSG may contribute to VAT reduction, improved adipocyte hormone levels, and changes in gut physiology and endocrinology.
    Endocrine Journal 01/2014; · 2.23 Impact Factor
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    ABSTRACT: Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are increasingly common cause of chronic liver disease worldwide. The diagnosis of NASH is challenging as most affected patients are symptom-free and the role of routine screening is not clearly established. Most patients with severe obesity who undergo bariatric surgery have NAFLD, which is associated insulin resistance, type 2 diabetes mellitus (T2DM), hypertension, and obesity-related dyslipidemia. The effective treatment for NAFLD is weight reduction through lifestyle modifications, antiobesity medication, or bariatric surgery. Among these treatments, bariatric surgery is the most reliable method for achieving substantial, sustained weight loss. This procedure is safe when performed by a skilled surgeon, and the benefits include reduced weight, improved quality of life, decreased obesity-related comorbidities, and increased life expectancy. Further research is urgently needed to determine the best use of bariatric surgery with NAFLD patients at high risk of developing liver cirrhosis and its role in modulating complications of NAFLD, such as T2DM and cardiovascular disease. The current evidence suggests that bariatric surgery for patients with severe obesity decreases the grade of steatosis, hepatic inflammation, and fibrosis. However, further long-term studies are required to confirm the true effects before recommending bariatric surgery as a potential treatment for NASH.
    Frontiers in Endocrinology 01/2014; 5:164.
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    ABSTRACT: Herein, we describe an extremely rare experience of a patient with liver cirrhosis from hepatitis C virus (LC-HCV) who underwent an ABO-incompatible living donor liver transplantation (ABO-I-LDLT) using a hepatitis B core antibody (HBc-Ab) positive donor's liver graft. A 47-year-old Japanese woman with end stage LC-HCV, as a recipient, was preoperatively administered rituximab, mycophenolate mofetil, and steroids without plasma exchange. A routine ABO-I-LDLT procedure was applied using her daughter's HBc-Ab positive liver graft. Prophylaxis of the hepatitis B virus (HBV) infection using hepatitis B immunoglobulin (HBIG) and entecavir had been properly administered. Three months after the ABO-I-LDLT, HCV hepatitis relapsed. To date, this patient has been under antiviral therapy and prophylaxis of HBV infection using HBIG, while entecavir has been continued. The cognitions and techniques with regard to ABO-I-LDLT, prophylaxis of HBV cross infection, various patterns of immunosuppression, and antiviral therapy for HCV relapse are indispensable in managing a transplant recipient. According to the prophylaxis of HBV cross infection under ABO-I-LDLT, it may be very important to keep the HBs-Ab titer higher than usual for HBV naïve recipients, because severe systemic immunosuppression can cause de novo hepatitis.
    Case reports in transplantation. 01/2014; 2014:507621.
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    ABSTRACT: The optimal cut-off value of the number of colorectal liver metastases (CRLM) to predict prognosis after hepatic resection remains unclear. This study was conducted to determine a suitable cut-off value. A total of 727 hepatectomized patients with CRLM were evaluated. We proposed the following optimal cut-off values: first, a small P-value for the log-rank test with no overlapping of the 95% confidence interval (CI) for median survival time using the Kaplan-Meier method and the hazard ratio (HR) using the Cox proportional hazards model and, second, the maximum HR value for accurate separation. For disease-free survival analysis, of the three group separations, A2 (1, 2-4, and ≥5) showed a small P-value and the largest HR, whereas two group separations, B2, B3 and B4 showed similarly small P-values, but B4 (1-4, ≥5) indicated the largest HR. Regarding the overall survival analysis, of the three group separations, A2 showed the smallest P-value, whereas the two group separations, B4 showed similarly small P-values, with the largest HR. Tumor number separation in patients with CRLM after hepatic resection should be performed using the A2 (1, 2-4, and ≥5) or B4 (1-4 and ≥5) classifications.
    Journal of hepato-biliary-pancreatic sciences. 12/2013;
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    ABSTRACT: Background:Circulating tumour cells (CTCs) have an important role in metastatic processes, but details of their basic characteristics remain elusive. We hypothesised that CD44-expressing CTCs show a mesenchymal phenotype and high potential for survival in hepatocellular carcinoma (HCC).Methods:Circulating CD44(+)CD90(+) cells, previously shown to be tumour-initiating cells, were sorted from human blood and their genetic characteristics were compared with those of tumour cells from primary tissues. The mechanism underlying the high survival potential of CD44-expressing cells in the circulatory system was investigated in vitro.Results:CD44(+)CD90(+) cells in the blood acquired epithelial-mesenchymal transition, and CD44 expression remarkably increased from the tissue to the blood. In Li7 and HLE cells, the CD44(high) population showed higher anoikis resistance and sphere-forming ability than did the CD44(low) population. This difference was found to be attributed to the upregulation of Twist1 and Akt signal in the CD44(high) population. Twist1 knockdown showed remarkable reduction in anoikis resistance, sphere formation, and Akt signal in HLE cells. In addition, mesenchymal markers and CD44s expression were downregulated in the Twist1 knockdown.Conclusions:CD44s symbolises the acquisition of a mesenchymal phenotype regulating anchorage-independent capacity. CD44s-expressing tumour cells in peripheral blood are clinically important therapeutic targets in HCC.British Journal of Cancer advance online publication, 3 December 2013; doi:10.1038/bjc.2013.759 www.bjcancer.com.
    British Journal of Cancer 12/2013; · 5.08 Impact Factor
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    ABSTRACT: Thrombotic thrombocytopenic purpura (TTP) is a serious hematologic disorder with a high rate of morbidity and mortality. We report here on the surgical and homological outcomes of laparoscopic splenectomy (LS) in a patient with refractory TTP. A 69-year-old Japanese woman was referred to our hospital because of purpura in the lower extremities. In addition to the marked thrombocytopenia, hemolytic anemia and progressive mental disorder were noted. The ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 motif 13) activity was undetectable and ADAMTS13 inhibitor was extremely increased. The diagnosis of TTP was made based on the clinical features and laboratory abnormalities. She received steroid-pulse therapy for 3 days, low-dose methylprednisolone continuous infusion and plasma exchange (PE) daily for 14 days. However, the patient was found to be refractory TTP to PE. The LS was performed at 15 days after diagnosis. The ADAMTS13 inhibitor was not detected after LS, and in addition, the platelet count had increased to over 100,000/mm3 on postoperative day 17. The patient remains in remission 24 months after surgery. The results of our case demonstrate that LS is a safe and reasonable treatment option for patients with TTP refractory to PE.
    Clinical Journal of Gastroenterology 12/2013; 6(6).
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    ABSTRACT: Background: Cancer cells synthesize substantial amounts of protoporphyrin IX( PPIX) from aminolevulinic acid( ALA). PPIX emits red fluorescence when illuminated under blue light. Photodynamic diagnosis (PDD), based on this phenomenon, is currently used; however, various microorganisms also show the same fluorescence with ALA when illuminated under blue light, resulting in false-positive PDD results. Purpose and Methods: To avoid misdiagnosis, we incorporated novel systems into the PDD system. ALA, blue light (wavelength, 380-450 nm), different kinds of cell lines, and bacteria were used in this in vitro study. We used a 70% deacetylated chitosan solution (DAC-70 Sol), developed in-house, as an antibacterial agent and prepared ALA/DAC-70 Sol, used as a novel photoimaging agent. The antibacterial function of ALA/DAC-70 Sol was examined in vitro, and the photodiagnostic effects on using the novel systems were clinically evaluated using bile from patients with biliary tract cancer. Results: DAC-70 Sol demonstrated an effective bactericidal function in vitro. Red fluorescence could clearly be identified, enabling the detection of cancer cells in the bile using ALA/DAC-70 Sol. Conclusions: Our novel systems have a great potential for use in clinical photodynamic cytodiagnosis( PDCD), which plays an important role in preoperative cancer chemotherapy.
    Gan to kagaku ryoho. Cancer & chemotherapy 11/2013; 40(12):1641-3.
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    ABSTRACT: Liver metastases resulting from primary choroidal malignant melanomas occur frequently and have a poor prognosis. As a result of advancements in multidisciplinary approaches, life expectancy can be increased when R0 resection is possible. Herein we report the surgical outcomes of pure laparoscopic posterior sectionectomy (PLPS) in a patient with a solitary liver metastasis resulting from choroidal malignant melanoma. The subject was a 46-year-old Japanese man who had received radiotherapy for primary right choroidal malignant melanoma 2 years before presenting at our hospital; he subsequently underwent ophthalmectomy as a result of the relapse. During follow-up, CT revealed a metastatic lesion in the liver S7, and interventional treatments were performed sequentially. The lesion still showed a tendency to enlarge, so we performed PLPS. On postoperative day 7, the patient was discharged from the hospital, and he started to receive adjuvant chemotherapy 2 weeks after PLPS. Although PLPS is deemed to be difficult for lesions in the upper part or posterior segment of the liver, we performed this modality safely.
    Asian Journal of Endoscopic Surgery 11/2013; 6(4):318-21.
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    ABSTRACT: Pure laparoscopic hemihepatectomy is still a challenging procedure. However, it is a minimally invasive liver surgery that leads to rapid recovery [1-5]. Intrahepatic cholangiocarcinoma has a poor prognosis, especially when it occurs with lymph node metastasis [6-8]. We recently had a patient who underwent a pure laparoscopic right hepatectomy and lymph nodes dissection for a large intrahepatic cholangiocarcinoma in the right liver by an anterior approach with hanging maneuver. Because the tumor was 77 × 50 mm in diameter, mobilization was performed after the devascularization of the right liver. After the division of the right hepatic artery and the right portal vein, short hepatic veins were sealed and divided with a bipolar vessel sealer from the anterior face of the vena cava, followed by the placement of a tape between the liver and the vena cava for hanging. By means of the hanging maneuver, parenchymal transection was performed with minimal blood loss, and the cut surface of the liver became plane. The operation time was 357 min, and the blood loss was 66 ml. A right hepatectomy and complete lymph node dissection adjacent to the hepatoduodenal ligament were performed successfully with a purely laparoscopic procedure. The postoperative hospital stay was 10 days. The final diagnosis of the intrahepatic cholangiocarcinoma with distant lymph node metastasis in the hepatoduodenal ligament was pT1N1M0 stage IIIb (International Union Against Cancer criteria). The laparoscopic procedure enabled the patient to have an early discharge and adjuvant chemotherapy of gemcitabine with S1 initiated immediately after discharge. We present a video of the described procedure.
    Surgical Endoscopy 10/2013; · 3.43 Impact Factor
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    ABSTRACT: Sunitinib was developed as a molecular-targeted drug to treat advanced renal cell carcinoma. It is not yet known whether liver damage occurs in patients with liver metastases of renal cell carcinoma after sunitinib administration. Here, we report the case of a patient with an inoperable massive liver metastasis of renal cell carcinoma for whom sunitinib administration was dramatically effective with no obvious evidence of liver damage. As a result, the liver metastasis could be resected. We emphasize the dramatic reduction in liver metastasis with sunitinib treatment, and the histopathological effects of sunitinib on the non-tumorous liver parenchyma. A 54-year-old Japanese woman was diagnosed with right renal cell carcinoma and underwent right nephrectomy 12 years earlier. She presented to a local clinic with right abdominal pain. A computed tomography scan showed a massive liver metastasis occupying her right hepatic lobe, and she was referred to our hospital for treatment. The diagnosis was not only liver metastasis, but also left renal metastasis. Oral administration of tyrosine kinase inhibitor sunitinib was started. Adverse events due to sunitinib included liver dysfunction, thrombocytopenia, and decreased hemoglobin, but she completed eight courses with the help of drug holidays and dose adjustments. Post-treatment computed tomography showed a dramatic reduction in size of her liver metastasis, enabling right lobectomy of her liver. Histopathological findings showed no obvious liver damage due to chemotherapy in non-cancerous parenchymal areas. With the availability of sunitinib, some patients with potentially unresectable massive liver metastases of renal cell carcinoma may be able to undergo major hepatectomy curatively and safely with little histopathological damage to non-tumorous liver parenchyma, thus improving their prognosis.
    Journal of Medical Case Reports 10/2013; 7(1):234.
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  • Cancer Research 08/2013; 73(8 Supplement):1160-1160. · 8.65 Impact Factor

Publication Stats

475 Citations
120.41 Total Impact Points

Institutions

  • 2001–2014
    • Iwate Medical University
      • • Department of Surgery
      • • Department of Anesthesiology
      • • Department of Pathology
      Morioka, Iwate, Japan
  • 2013
    • Kumamoto University
      • Department of Gastroenterological Surgery (Med Grad)
      Kumamoto, Kumamoto Prefecture, Japan
  • 2011
    • Yamamoto General Hospital
      Edo, Tōkyō, Japan