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Featured researches published by Katsushi Hiramatsu.


BMC Clinical Pathology | 2015

Ruptured hepatic metastases of cutaneous melanoma during treatment with vemurafenib: an autopsy case report

Takuto Nosaka; Katsushi Hiramatsu; Tomoyuki Nemoto; Yasushi Saito; Yoshihiko Ozaki; Kazuto Takahashi; Tatsushi Naito; Kazuya Ofuji; Hidetaka Matsuda; Masahiro Ohtani; Hiroyuki Suto; Yoshiaki Imamura; Yasunari Nakamoto

BackgroundThe spontaneous rupture of hepatic metastases is rare compared to that of primary hepatic tumors. In addition, vemurafenib, a selective inhibitor of the mutant BRAF protein or gene product, has been reported to be extremely effective in patients with metastatic melanoma who harbor a BRAF V600E mutation.Case presentationA 44-year-old female had previously undergone surgery for resection of a malignant melanoma in the lower right leg. Four years later, hepatic metastases became apparent, and transcatheter arterial embolization (TAE) was performed. Then she underwent treatment with vemurafenib. The size of the hepatic metastases markedly decreased. Two months later, they enlarged rapidly and ruptured, requiring emergency TAE. However, the patient developed hemorrhagic shock and died of renewed intra-abdominal bleeding on the 26th postoperative day.ConclusionsThis is a rare case of ruptured hepatic metastases of malignant melanoma during treatment with vemurafenib. Postmortem examination and immunohistochemical analysis indicated reactivation of the mitogen-activated protein kinase pathway in the metastatic tumor, suggesting secondary resistance to vemurafenib as the possible underlying mechanism.


Oncology Reports | 2016

Effect of green tea catechins on gastric mucosal dysplasia in insulin-gastrin mice

Takashi Ohno; Masahiro Ohtani; Hiroyuki Suto; Makoto Ohta; Yoshiaki Imamura; Hidetaka Matsuda; Katsushi Hiramatsu; Tomoyuki Nemoto; Yasunari Nakamoto

Green tea catechins (GTCs) have been implicated in various physiological effects, including anti-carcinogenic activities. In the present study, we evaluated the effects of GTCs specifically on the development of gastritis and pre-malignant lesions in insulin-gastrin mice. Nine-week-old male INS-GAS mice (n=38) were supplemented with GTCs for 4 and 28 weeks, and their body weights, serum gastrin levels, histopathology and pro-inflammatory cytokine levels in gastric tissue and mucosal cell proliferation were monitored. Body weights of the GTC-treated mice were significantly lower than those of the untreated controls (P≤0.05). Serum gastrin levels were suppressed at the age of 37-weeks (P≤0.05). The histopathological scores indicated that the extent of dysplasia was significantly diminished (P≤0.05), although GTC supplementation did not affect the inflammation scores. The messenger RNA levels of interferon (IFN)-γ were significantly reduced at the age of 13 weeks (P≤0.05), although the changes did not reach statistical significance at the age of 37 weeks (P=0.056). The labeling index of Ki-67 immunohistochemistry was significantly decreased (P≤0.05). These results demonstrated that GTCs may play a protective role in the development of gastritis and pre-malignant lesions via an IFN-γ, gastrin, and mucosal cell proliferation-dependent mechanism in this rodent model and potentially in humans.


Endoscopy International Open | 2016

Preoperative diagnosis of cavernous hemangioma presenting with melena using wireless capsule endoscopy of the small intestine

Yu Akazawa; Katsushi Hiramatsu; Takuto Nosaka; Yasushi Saito; Yoshihiko Ozaki; Kazuto Takahashi; Tatsushi Naito; Kazuya Ofuji; Hidetaka Matsuda; Masahiro Ohtani; Tomoyuki Nemoto; Hiroyuki Suto; Akio Yamaguchi; Yoshiaki Imamura; Yasunari Nakamoto

Background and study aims: Primary neoplasms of the small intestine are relatively rare in all age groups, accounting for about 5 % of all gastrointestinal tumors 1. Cavernous hemangiomas of the small intestine are also rare, can cause gastrointestinal bleeding, and are extremely difficult to diagnose preoperatively 2. We present a patient who presented with melena and iron deficiency anemia, for whom wireless capsule endoscopy and single-balloon enteroscopy facilitated the diagnosis of cavernous hemangioma.


Diagnostic and Therapeutic Endoscopy | 2016

Long-Term Endoscopic Follow-Up of Patients with Chronic Radiation Proctopathy after Brachytherapy for Prostate Cancer

Masahiro Ohtani; Hiroyuki Suto; Takuto Nosaka; Yasushi Saito; Yoshihiko Ozaki; Ryoko Hayama; Tatsushi Naito; Kazuto Takahashi; Kazuya Ofuji; Hidetaka Matsuda; Katsushi Hiramatsu; Tomoyuki Nemoto; Hiroki Shioura; Hirohiko Kimura; Yoshitaka Aoki; Osamu Yokoyama; Yasunari Nakamoto

Background. Chronic radiation proctopathy (CRP) is late toxicity and associated with morbidity. Aim. To investigate the predictors of prognosis in patients with CRP after brachytherapy (BT). Methods. One hundred four patients with prostate cancer were treated with BT or BT followed by external-beam radiotherapy (BT + EBRT). We retrospectively investigated the 5-year incidence of rectal bleeding and endoscopic findings of CRP using the Vienna Rectoscopy Score (VRS). Twenty patients with VRS ≥ 1 were divided into the improved VRS group without treatment, unchanged VRS group, and treated group. The parameters associated with alteration of VRS were analyzed. Results. The incidence of rectal bleeding was 24%. The risk of rectal bleeding was higher in patients treated with BT + EBRT compared to those treated with BT (p < 0.0001). The incidence of superficial microulceration was higher in the improved VRS group than in the unchanged VRS group (p < 0.05). The incidence of multiple confluent telangiectasia or superficial ulcers > 1 cm2 was higher in the treated group than in both the improved and unchanged VRS groups (p < 0.05). Conclusions. Patients treated with BT + EBRT have a high risk of CRP. Endoscopic findings were useful for prognostic prediction of CRP.


BMC Cancer | 2015

Pituitary metastasis of hepatocellular carcinoma presenting with panhypopituitarism: a case report.

Tomoko Tanaka; Katsushi Hiramatsu; Takuto Nosaka; Yasushi Saito; Tatsushi Naito; Kazuto Takahashi; Kazuya Ofuji; Hidetaka Matsuda; Masahiro Ohtani; Tomoyuki Nemoto; Hiroyuki Suto; Tatsuya Yamamoto; Hirohiko Kimura; Yasunari Nakamoto

BackgroundMetastasis to the pituitary gland is extremely rare and is often detected incidentally by symptoms associated with endocrine dysfunction. Breast and lung cancer are the most common primary metastasizing to pituitary gland. Metastasis from hepatocellular carcinoma to the pituitary gland is extremely rare, with only 10 cases having been previously reported. We present here the first case of pituitary metastasis of hepatocellular carcinoma presenting with panhypopituitarism diagnosed by magnetic resonance imaging.Case presentationWe report the case of an 80-year-old Japanese woman who presented with the sudden onset of hypotension and bradycardia after having previously been diagnosed with hepatocellular carcinoma. Based on low levels of pituitary hormones, she was diagnosed with panhypopituitarism caused by metastasis of the hepatocellular carcinoma to the pituitary gland. Magnetic resonance imaging with arterial spin-labeling was effective in the differential diagnosis of the intrasellar tumor. The patient died despite hormone replacement therapy because of hypovolemic shock.ConclusionMetastasis to the pituitary gland causes various non-specific symptoms, so it is difficult to diagnose. The present case emphasizes the importance of diagnostic imaging in identifying these metastases. Clinicians should consider the possibility of pituitary metastasis in patients with malignant tumors who demonstrate hypopituitarism.


Journal of Medical Virology | 2018

Genetic polymorphism and decreased expression of HLA class II DP genes are associated with HBV reactivation in patients treated with immunomodulatory agents

Hidetaka Matsuda; Katsushi Hiramatsu; Yu Akazawa; Takuto Nosaka; Yasushi Saito; Yoshihiko Ozaki; Ryoko Hayama; Kazuto Takahashi; Tatsushi Naito; Kazuya Ofuji; Masahiro Ohtani; Tomoyuki Nemoto; Yukio Hida; Hideki Kimura; Yoshihiro Soya; Yasunari Nakamoto

Hepatitis B virus (HBV) reactivation can be triggered by immunosuppressive chemotherapy. HLA class II molecules may play a role in HBV reactivation. Genetic polymorphism and mRNA expression of HLA class II were examined in patients with latent HBV infection treated with immunosuppressive therapies. Subjects with resolved HBV infection who had undergone treatment with immunosuppressive chemotherapies were retrospectively enrolled (n = 42) and divided into reactivated (n = 9) and non‐reactivated groups (n = 33). Patients were genotyped for 17 single nucleotide polymorphisms (SNPs) within HLA class II DPA1, and DPB1, and mRNA expression levels of HLA class II genes were assessed. The frequency of the AA genotype of rs872956, a SNP in HLA‐DPB1, was significantly higher in the reactivated group than in the non‐reactivated group (55.6% vs 12.1%, P < 0.05). The frequencies of the T allele and non‐AA genotypes (AT/TT) of rs3116996 (located in DPB1) were significantly higher in the reactivated group (T allele frequency: 16.7% vs 0.0% [P < 0.01], non‐AA genotype frequency: 22.2% vs 0.0% [P < 0.05]). Multivariate logistic regression identified the AA genotype of rs872956 as an independent protective factor against HBV reactivation (odds ratio [OR] = 18.1, 95% confidence interval [CI] = 2.6‐126.7, P < 0.01). mRNA expression of HLA‐DPB1 was lower in the HBV reactivated group than in the non‐reactivated group (median 276.1 ± 165.6/β‐actin vs 371.4 ± 407.5/β‐actin [P < 0.05]). These results suggest the involvement of HLA class II molecules in HBV reactivation after treatment with immunomodulatory agents.


Journal of Medical Virology | 2017

Identification of novel variants in HLA class II region related to HLA DPB1 expression and disease progression in patients with chronic hepatitis C

Katsushi Hiramatsu; Hidetaka Matsuda; Tomoyuki Nemoto; Takuto Nosaka; Yasushi Saito; Tatsushi Naito; Kazuto Takahashi; Kazuya Ofuji; Masahiro Ohtani; Hiroyuki Suto; Toshihiro Yasuda; Yukio Hida; Hideki Kimura; Yoshihiro Soya; Yasunari Nakamoto

Recent genome‐wide studies have demonstrated that HLA class II gene may play an important role in viral hepatitis. We studied genetic polymorphism and RNA expression of HLA class II genes in HCV‐related liver diseases. The study was performed in groups consisting of 24 patients with HCV‐related liver disease (12 of persistent normal ALT: PNALT group and 12 of advanced liver disease: ALD group) and 26 patients without HCV infection (control group). In PBMC samples, RNA expression of HLA class II genes (HLA‐DPA1, DPB1, DQA1, DQB1, and DRB1) was analyzed by real‐time RT‐PCR. Furthermore, 22 single nucleotide polymorphisms (SNPs) in HLA class II gene and two SNPs in IL28B gene were genotyped by genetic analyzer (GENECUBE®). In expression analysis, only DPB1 level was significantly different. Mean expression level of DPB1gene in control group was 160.0, PNALT group 233.8, and ALD group 465.0 (P < 0.01). Of 24 SNPs, allele frequencies were statistically different in two SNPs (rs2071025 and rs3116996) between PNALT groups and ALD group (P < 0.01). In rs2071025, TT genotype was frequently detected in ALD group and expression level was significantly higher than the other genotypes (449.2 vs 312.9, P < 0.01). In rs3116996, TA or TT (non AA) genotype was frequently detected in ALD group and expression level was significantly higher than genotype AA (457.1 vs 220.9, P < 0.01). Genotyping and expression analysis in HLA class II gene revealed that two SNPs of HLA‐DPB1 (rs2071025 and rs3116996) were significantly correlated to RNA expression and progression of HCV‐related liver diseases.


Clinical Journal of Gastroenterology | 2017

A case of protein-losing enteropathy caused by sclerosing mesenteritis diagnosed with capsule endoscopy and double-balloon endoscopy

Yasushi Saito; Katsushi Hiramatsu; Takuto Nosaka; Yoshihiko Ozaki; Kazuto Takahashi; Tatsushi Naito; Kazuya Ofuji; Hidetaka Matsuda; Masahiro Ohtani; Tomoyuki Nemoto; Yoshiaki Imamura; Yasunari Nakamoto

A 75-year-old man presented with abdominal distension, hypoproteinemia, ascites and a 35-mm mass in the small bowel mesentery. Laparotomy was performed, and he was diagnosed with sclerosing mesenteritis. His clinical condition improved, with computed tomography (CT) showing tumor shrinkage and decreasing ascites after administration of prednisolone; however, on drug withdrawal, abdominal fullness recurred and CT revealed an enlarging tumor and increasing ascites. Capsule endoscopy (CE) and double-balloon enteroscopy (DBE) were performed to further investigate hypoalbuminemia, which revealed white villi, white nodules, white debris, and mucosal edema in the jejunum. Biopsies from the jejunal mucosa demonstrated infiltration by chronic inflammatory cells consisting mostly of lymphocytes and plasma cells, with marked lymphangiectasia of the lamina propria and submucosa. A fecal alpha-1-antitrypsin clearance test revealed abnormal leakage from the gastrointestinal tract, confirming that hypoalbuminemia was secondary to protein-losing enteropathy (PLE). The incidence of sclerosing mesenteritis accompanied by PLE is very rare. Only six cases have been reported so far. CE and DBE were helpful for diagnosing this condition, and should be performed in patients in whom the cause of hypoalbuminemia is unknown, and in those with PLE.


Clinical Journal of Gastroenterology | 2015

A case of Helicobacter pylori-negative intramucosal well-differentiated gastric adenocarcinoma with intestinal phenotype

Yoshihiko Ozaki; Hiroyuki Suto; Takuto Nosaka; Yasushi Saito; Tatsushi Naito; Kazuto Takahashi; Kazuya Ofuji; Hidetaka Matsuda; Masahiro Ohtani; Katsushi Hiramatsu; Tomoyuki Nemoto; Yoshiaki Imamura; Yasunari Nakamoto


Clinical Journal of Gastroenterology | 2018

Reactivation of intraabdominal tuberculous lymphadenopathy after drug-eluting beads transcatheter arterial chemoembolization in a patient with hepatocellular carcinoma

Yosuke Murata; Katsushi Hiramatsu; Yumi Yoshida; Yu Akazawa; Yasushi Saito; Takuto Nosaka; Yoshihiko Ozaki; Ryoko Hayama; Kazuto Takahashi; Tatsushi Naito; Kazuya Ofuji; Hidetaka Matsuda; Masahiro Ohtani; Tomoyuki Nemoto; Yasunari Nakamoto

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