Faculty Profiles - IWAMURO Masaya

Metastatic tumors in the duodenum: A report of two cases Reviewed

Masaya Iwamuro, Hirokazu Uetsuka, Kiyoshi Makihata, Kazuhide Yamamoto

JOURNAL OF CANCER RESEARCH AND THERAPEUTICS 11 ( 3 ) 648 2015.7

Language：English Publishing type：Research paper (scientific journal) Publisher：MEDKNOW PUBLICATIONS & MEDIA PVT LTD

Two cases are presented involving a 71-year-old male with adenocarcinoma of the lung and a 57-year-old male with adenocarcinoma of the sigmoid colon, each with metastatic lesions located in the duodenal bulb. Each lesion appeared as a submucosal tumor with an ulcer at the center. Lymph node swelling in the hepatoduodenal ligament was also found to precede the emergence of each duodenal metastasis. These cases indicate that involvement of the lymph node in the hepatoduodenal ligament may be a forerunner of duodenal metastasis.

DOI： 10.4103/0973-1482.137675

ICU管理が必要となったmulticentric Castleman disease(MCD)/TAFRO症候群(2)

Gastric pseudopolyposis formed after recovery from gastric gangrene Reviewed

Masaya Iwamuro, Yoshihisa Hanayama, Fumio Otsuka, Hiroyuki Okada

DIGESTIVE AND LIVER DISEASE 47 ( 6 ) E9 - E9 2015.6

治療方針決定に免疫染色が有用だった腺癌の1例

石川俊二郎, 岩室雅也, 灘隆宏, 木村耕介, 中村絵里, 萩谷英大, 長谷川功, 浅野喜久子, 早稲田公一, 花山宜久, 近藤英生, 大塚文夫

日本病院総合診療医学会雑誌 8 ( 2 ) 86 - 87 2015.6

木村耕介, 近藤英生, 松岡賢市, 灘隆弘, 中村絵里, 岩室雅也, 浅野喜久子, 長谷川巧, 萩谷英大, 早稲田公一, 花山宜久, 村上和敏, 飯田淳義, 塚原紘平, 鵜川豊世武, 谷本光音, 吉野正, 大塚文男

日本リンパ網内系学会会誌 55 115 - 115 2015.6

Hyperintense Lesion in the Pons in Intravascular Lymphoma Reviewed

Masaya Iwamuro, Kosuke Kimura, Eisei Kondo, Fumio Otsuka

INTERNAL MEDICINE 54 ( 18 ) 2421 - 2422 2015

Magnifying Endoscopic Observation of Duodenal Involvement of Follicular Lymphoma before and after Chemotherapy Reviewed

Masaya Iwamuro, Hiroyuki Okada, Katsuyoshi Takata, Nobuharu Fujii, Seiji Kawano, Yoshiro Kawahara, Tadashi Yoshino, Kazuhide Yamamoto

INTERNAL MEDICINE 54 ( 14 ) 1741 - 1745 2015

Language：English Publishing type：Research paper (scientific journal) Publisher：JAPAN SOC INTERNAL MEDICINE

A 60-year-old Japanese man was diagnosed with systemic follicular lymphoma with duodenal, jejunal, and ileal involvement. The duodenal lesion showed typical endoscopic features with multiple whitish granules. Chemotherapy with bendamustine and rituximab was administered, and complete remission was confirmed by CT scanning and positron emission tomography scanning. Although the duodenal granular lesions did not completely disappear, magnifying observation for the remaining lesions showed no evidence of residual lymphoma. Complete remission was pathologically confirmed by biopsy examinations. This case suggests the usefulness of magnifying observation in evaluating the effects of treatment for duodenal follicular lymphoma lesions.

DOI： 10.2169/internalmedicine.54.4390

Morphological Changes in a Pyogenic Granuloma of the Esophagus Observed over Three Years Reviewed

Masaya Iwamuro, Hiroyuki Okada, Takehiro Tanaka, Keisuke Hori, Masahide Kita, Seiji Kawano, Yoshiro Kawahara, Kazuhide Yamamoto

INTERNAL MEDICINE 54 ( 14 ) 1737 - 1740 2015

Language：English Publishing type：Research paper (scientific journal) Publisher：JAPAN SOC INTERNAL MEDICINE

A 78-year-old Japanese man underwent routine esophagogastroduodenoscopy, during which a reddish, flat elevated lesion was observed in the middle third of the esophagus. A bright red area of protrusion appeared in the center of the elevated lesion three months later, and the protruded nodule grew to be a blood blister six months after the initial endoscopy examination. The morphology of the lesion changed from a protruded nodule to a mass with two humps that subsequently returned to a single hump during the three-year observation period. A histological diagnosis of pyogenic granuloma was made based on a biopsy performed at six months. This report illustrates a rare case of an esophageal pyogenic granuloma presenting with a unique endoscopic appearance and morphologic changes. Endoscopic ultrasonography images are also presented.

DOI： 10.2169/internalmedicine.54.4265

Ectopic pancreas in the stomach successfully resected by endoscopic submucosal dissection Reviewed

Masaya Iwamuro, Takao Tsuzuki, Shogen Ohya, Hiroyuki Okada, Takehiro Tanaka, Keisuke Hori, Masahide Kita, Seiji Kawano, Yoshiro Kawahara, Kazuhide Yamamoto

Case Reports in Medicine 2015 1 2015

Language：English Publishing type：Research paper (scientific journal) Publisher：Hindawi Limited

A 32-year-old Japanese man presented with a gastric submucosal tumor. Esophagogastroduodenoscopy showed a sessile submucosal tumor measuring approximately 10 mm in diameter on the greater curvature of the gastric antrum. Endoscopic ultrasonography examination revealed a solid tumor with a diameter of 11.8 mm, which was located in the deep mucosal and submucosal layers. The internal echogenicity was homogenous and hypoechoic. Biopsy examinations were performed twice but were not diagnostic since only the intact mucosal layer was obtained. The patient was subsequently diagnosed with ectopic pancreas in the stomach by endoscopic submucosal dissection (ESD). This case underscores the usefulness of the ESD technique for the pathological diagnosis of gastric submucosal tumors.

DOI： 10.1155/2015/147927

Scopus

A Nephrostomy-associated Urinary Tract Infection Caused by Elizabethkingia meningoseptica Reviewed

Hideharu Hagiya, Hiroko Ogawa, Yusuke Takahashi, Kou Hasegawa, Masaya Iwamuro, Fumio Otsuka

INTERNAL MEDICINE 54 ( 24 ) 3233 - 3236 2015

Language：English Publishing type：Research paper (scientific journal) Publisher：JAPAN SOC INTERNAL MEDICINE

We report a case of nephrostomy-associated urinary tract infection caused by Elizabethkingia meningoseptica that occurred in a patient with retroperitoneal fibrosis. Though conventional identification methods failed to detect the causative organism, it was identified on the basis of the complete sequencing of 16S rRNA. Four weeks of levofloxacin and minocycline administration successfully eradicated the infection. E. meningoseptica rarely causes urinary tract infections, and we believe that this is the first such case in which the isolate was genetically confirmed. The accurate identification of the organism is necessary for the provision of appropriate treatment and to obtain a better understanding of its epidemiology and pathogenicity.

DOI： 10.2169/internalmedicine.54.4998

An effective and safe sedation technique combining target-controlled infusion pump with propofol, intravenous pentazocine, and bispectral index monitoring for peroral double-balloon endoscopy. Reviewed International journal

Seiji Kawano, Hiroyuki Okada, Masaya Iwamuro, Yoshiyasu Kouno, Kou Miura, Toshihiro Inokuchi, Hiromitsu Kanzaki, Keisuke Hori, Keita Harada, Sakiko Hiraoka, Yoshiro Kawahara, Kazuhide Yamamoto

Digestion 91 ( 2 ) 112 - 6 2015

Language：English Publishing type：Research paper (scientific journal)

BACKGROUND/AIMS: Because peroral double-balloon endoscopy (DBE) is a time-consuming, painful procedure, sedation with analgesics, and/or anesthetics is generally required. The aim of this prospective study was to investigate the safety and efficacy of our sedation protocol for peroral DBE, which consisted of target-controlled infusion (TCI) anesthesia with propofol, an intravenous bolus of pentazocine, and bispectral index (BIS) monitoring. METHODS: A total of 34 consecutive patients who underwent DBE by the oral approach were enrolled. Patients were primarily sedated with a continuous infusion of propofol and adjusted in accordance with the BIS levels. The bolus infusion of pentazocine was performed when the propofol infusion was insufficient. The primary outcome measure of this study was to ensure the safety and efficacy of this sedation technique. The secondary purpose was to identify the characteristics of the patient who required the bolus infusion of pentazocine. RESULTS: Five patients (14.7%) required a reduction in the dose of propofol. However, no patient experienced any serious adverse events. All patients (100%) and 80.6% (25/31) of endoscopists answered that the sedation protocol was 'excellent' or 'enough' for peroral DBE. Eleven patients (32.3%) required a bolus injection of pentazocine. Age <60 years and a total procedure time of >70 min were significant risk-factors for pentazocine use. CONCLUSIONS: A combination of propofol via TCI pump, bolus injection of pentazocine as needed, and BIS monitoring was a safe and effective procedure for peroral DBE. Reasonable satisfaction indices were obtained from both patients and endoscopists. Pentazocine was required for young patients and in cases with longer procedure times.

DOI： 10.1159/000369614

Hereditary Spherocytosis in a Middle-aged Man Complicated with Common Bile Duct Stones Reviewed

Hiroaki Sawahara, Masaya Iwamuro, Ryo Harada, Masao Yoshioka, Takefumi Niguma, Tetsushige Mimura, Kazuhide Yamamoto

INTERNAL MEDICINE 54 ( 12 ) 1509 - 1512 2015

Language：English Publishing type：Research paper (scientific journal) Publisher：JAPAN SOC INTERNAL MEDICINE

Hereditary spherocytosis is the most common form of hemolytic anemia and is characterized by spherical, osmotically fragile erythrocytes that are selectively trapped by the spleen. Hereditary spherocytosis is typically diagnosed in childhood. We herein experienced a rare case of hereditary spherocytosis diagnosed in middle age. The patient presented with cholelithiasis and hyperbilirubinemia. He had no anemia and was asymptomatic with mild splenomegaly. In the differential diagnosis of these symptoms, the possibility of hereditary spherocytosis should be considered, even in patients who are middle-aged and lack anemia.

DOI： 10.2169/internalmedicine.54.4812

Ultrastructural Analysis of an Enterolith Composed of Deoxycholic Acid Reviewed

Masaya Iwamuro, Yuichi Miyashima, Takahiro Yoshioka, Toshihiro Murata, Yoshio Miyabe, Yoshinari Kawai, Haruo Urata, Hidenori Shiraha, Hiroyuki Okada, Kazuhide Yamamoto

ACTA MEDICA OKAYAMA 68 ( 6 ) 369 - 374 2014.12

Language：English Publishing type：Research paper (scientific journal) Publisher：OKAYAMA UNIV MED SCHOOL

A 67-year-old Japanese man underwent enterotomy because of enterolith ileus. Component analysis by infrared spectroscopy revealed that the enterolith was composed of a high concentration of deoxycholic acid. We further analyzed and compared the ultrastructure of the enterolith and a commercially available powdered form of deoxycholic acid by means of scanning electron microscopy and energy dispersive X-ray spectroscopy. Energy dispersive X-ray spectroscopy analysis revealed that the ratios of carbon and oxygen in the enterolith were equal to those in the deoxycholic acid powder. Scanning electron microscopy analysis showed rectangular prism-shaped particles on the surface of the enterolith. This structure was similar to that of the deoxycholic acid powder. The surgically removed enterolith had a twisted and coiled appearance. Possible mechanisms underlying the formation of this unique form are discussed.

DOI： 10.18926/AMO/53026

Ultrastructural analysis of a gastric persimmon phytobezoar Reviewed

Masaya Iwamuro, Haruo Urata, Masumi Furutani, Yoshinari Kawai, Hidenori Shiraha, Akinobu Takaki, Hiroyuki Okada, Kazuhide Yamamoto

CLINICS AND RESEARCH IN HEPATOLOGY AND GASTROENTEROLOGY 38 ( 4 ) E85 - E87 2014.9

The efficacy and safety of single-session endoscopic ultrasound-guided fine needle aspiration and endoscopic retrograde cholangiopancreatography for evaluation of pancreatic masses. International journal

Yasuhiro Noma, Hirofumi Kawamoto, Hironari Kato, Masaya Iwamuro, Ken Hirao, Masakuni Fujii, Koichiro Tsutsumi, Shigeru Horiguchi, Naoki Yamamoto, Ichiro Sakakihara, Takeshi Tomoda, Kazuyuki Matsumoto, Hiroyuki Okada, Kazuhide Yamamoto

Hepato-gastroenterology 61 ( 134 ) 1775 - 9 2014.9

Language：English Publishing type：Research paper (scientific journal)

BACKGROUND/AIMS: There have been limited studies evaluating single-session EUS-FNA and ERCP for evaluation of pancreatic masses. The aim of this study was to determine the safety of single-session EUS-FNA and ERCP, and to compare the diagnostic accuracies of cytodiagnosis by EUS-FNA, ERCP, and their combination. METHODOLOGY: A total of 100 patients with pancreatic masses were prospectively enrolled. All patients underwent single-session EUS-FNA and ERCP. The main outcome measurement was frequency of post-procedural complications. Another measurement was diagnostic accuracy of cytodiagnosis by EUS-FNA, ERCP, and their combination. RESULTS: Procedure-related pancreatitis occurred in 10 patients, but all patients were conservatively managed. Cytodiagnosis by EUS-FNA was significantly superior to ERCP in accuracy. In patients with a pancreatic head mass, 3 cases of false negative EUS-FNA were positive on ERCP. The combination procedures improved accuracy compared with EUS-FNA alone. By contrast, in the subgroup of the pancreatic body or tail mass, the combination of EUS-FNA and ERCP did not improve cytodiagnosis compared to that with EUS-FNA alone. CONCLUSIONS: Single-session EUS-FNA and ERCP appears to be as safe as performing each procedure separately. EUS-FNA should be considered the principal procedure for cytodiagnosis. ERCP has only a complementary role in patients with pancreatic head mass.

DOI： 10.5754/hge13523

An expanded training program for endosonographers improved self-diagnosed accuracy of endoscopic ultrasound-guided fine-needle aspiration cytology of the pancreas. Reviewed

Harada R, Kato H, Fushimi S, Iwamuro M, Inoue H

Scand J Gastroenterol. 49 ( 9 ) 1119 - 1123 2014.9

A case of follicular lymphoma involving the colon

Shiho Takashima, Masaya Iwamuro, Tomoki Inaba, Satoko Nakamura, Koichi Izumikawa, Shigenao Ishikawa, Masaki Wato, Kozo Kawai, Hiroyuki Okada, Kazuhide Yamamoto

Gastroenterological Endoscopy 56 ( 8 ) 2393 - 2399 2014.8

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Gastroenterological Endoscopy Society

A 77-year-old Japanese man was referred to Kagawa Prefectural Central Hospital for further investigation of a positive fecal occult blood test. Colonoscopy revealed an elevated lesion of 35 mm in diameter in the ascending colon. The lesion had a submucosal tumor-like morphology, lacking erosions or ulcers. Histological examination of the biopsy specimen revealed dense infiltration of small-sized neoplastic lymphoid cells. Based on the immunohistochemical examinations, the colonic tumor was diagnosed as follicular lymphoma. CT scanning revealed systemic lymph-adenopathy in addition to the colonic tumor. Six courses of CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) chemotherapy plus rituximab were administered as the first-line treatment. After completion of the regimen, the colonic tumor had disappeared and the lymph-adenopathy had partially regressed. However, a mesenteric lymph node had become enlarged. Bendamustine was therefore administered to treat the relapse of follicular lymphoma. Among the various parts of the gastrointestinal tract, the small intestines (especially the duodenum) are the most common site of follicular lymphoma involvement, and the colorectum is less frequently affected. This paper illustrates a rare case of systemic follicular lymphoma with colonic involvement.

Scopus

Establishment of a pancreatic stem cell line from fibroblast-derived induced pluripotent stem cells Reviewed

Takashi Kuise, Hirofumi Noguchi, Hiroshi Tazawa, Takashi Kawai, Masaya Iwamuro, Issei Saitoh, Hitomi Usui Kataoka, Masami Watanabe, Yasufumi Noguchi, Toshiyoshi Fujiwara

BIOMEDICAL ENGINEERING ONLINE 13 2014.5

Language：English Publishing type：Research paper (scientific journal) Publisher：BIOMED CENTRAL LTD

Background: For cell therapies to treat diabetes, it is important to produce a sufficient number of pancreatic endocrine cells that function similarly to primary islets. Induced pluripotent stem (iPS) cells represent a potentially unlimited source of functional pancreatic endocrine cells. However, the use of iPS cells for laboratory studies and cell-based therapies is hampered by their high tumorigenic potential and limited ability to generate pure populations of differentiated cell types in vitro. The purpose of this study was to establish a pancreatic stem cell line from iPS cells derived from mouse fibroblasts.
Methods: Mouse iPS cells were induced to differentiate into insulin-producing cells by a multi-step differentiation protocol, which was conducted as described previously with minor modifications. Selection of the pancreatic stem cell was based on morphology and Pdx1 expression. The pancreatic potential of the pancreatic stem cells was evaluated using a reverse transcription PCR, real-time PCR, immunofluorescence, and a glucose challenge test. To assess potential tumorigenicity of the pancreatic stem cells, the cells were injected into the quadriceps femoris muscle of the left hindlimb of nude mice.
Results: The iPS-derived pancreatic stem cells expressed the transcription factor -Pdx1- a marker of pancreatic development, and continued to divide actively beyond passage 80. Endocrine cells derived from these pancreatic stem cells expressed insulin and pancreatic genes, and they released insulin in response to glucose stimulation. Mice injected with the pancreatic stem cells did not develop tumors, in contrast to mice injected with an equal number of iPS cells.
Conclusion: This strategy provides a new approach for generation of insulin-producing cells that is more efficient and safer than using iPS cells. We believe that this approach will help to develop a patient-specific cell transplantation therapy for diabetes in the near future.

DOI： 10.1186/1475-925X-13-64

Potential of adenovirus-mediated REIC/Dkk-3 gene therapy for use in the treatment of pancreatic cancer Reviewed

Daisuke Uchida, Hidenori Shiraha, Hironari Kato, Teruya Nagahara, Masaya Iwamuro, Junro Kataoka, Shigeru Horiguchi, Masami Watanabe, Akinobu Takaki, Kazuhiro Nouso, Yasutomo Nasu, Takahito Yagi, Hiromi Kumon, Kazuhide Yamamoto

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY 29 ( 5 ) 973 - 983 2014.5

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY

Background and AimThe reduced expression in immortalized cells REIC/the dickkopf 3 (Dkk-3) gene, tumor suppressor gene, is downregulated in various malignant tumors. In a prostate cancer study, an adenovirus vector carrying the REIC/Dkk-3 gene (Ad-REIC) induces apoptosis. In the current study, we examined the effects of REIC/Dkk-3 gene therapy in pancreatic cancer.
MethodsREIC/Dkk-3 expression was assessed by immunoblotting and immunohistochemistry in the pancreatic cancer cell lines (ASPC1, MIAPaCa2, Panc1, BxPC3, SUIT-2, KLM1, and T3M4) and pancreatic cancer tissues. The Ad-REIC agent was used to investigate the apoptotic effect in vitro and antitumor effects in vivo. We also assessed the therapeutic effects of Ad-REIC therapy with gemcitabine.
ResultsThe REIC/Dkk-3 expression was lost in the pancreatic cancer cell lines and decreased in pancreatic cancer tissues. Ad-REIC induced apoptosis and inhibited cell growth in the ASPC1 and MIAPaCa2 lines in vitro, and Ad-REIC inhibited tumor growth in the mouse xenograft model using ASPC1 cells. The antitumor effect was further enhanced in combination with gemcitabine. This synergistic effect may be caused by the suppression of autophagy via the enhancement of mammalian target of rapamycin signaling.
ConclusionsAd-REIC induces apoptosis and inhibits tumor growth in pancreatic cancer cell lines. REIC/Dkk-3 gene therapy is an attractive therapeutic tool for pancreatic cancer.

DOI： 10.1111/jgh.12501