Hirofumi Kiyokawa

Dr. Hirofumi Kiyokawa

orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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Verified
Journal Article
Open access
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HYHiroshi Yasuda
Hiroshi Yasuda
MNMasatoshi Nakagawa
Masatoshi Nakagawa
HKHirofumi Kiyokawa
Hirofumi Kiyokawa
EYEisaku Yoshida
Eisaku Yoshida
TYToru Yoshimura
Toru Yoshimura
MSMotoharu Seiki
Motoharu Seiki
Laminin (Ln)-332 consists of α3, β3, and γ2 chains, which mediate epithelial cell adhesion to the basement membrane. Ln-γ2, a component of Ln-332, is frequently expressed as a monomer in the invasion front of several types of malignant tissues without simultaneous expression of Ln-α3 and/or Ln-β3 chains. Moreover, monomeric Ln-γ2 induces tumor cell proliferation and migration in vitro. These unique biological activities indicate that monomeric Ln-γ2 could be a candidate biomarker for early cancer surveillance. However, the present immune method for monomeric Ln-γ2 detection can only predict its expression, since no antibody that specifically reacts with monomeric γ2, but not with heterotrimeric γ2 chain, is commercially available. We have, therefore, developed monoclonal antibodies to specifically detect monomeric Ln-γ2, and devised a highly sensitive method to measure serum monomeric Ln-γ2 levels using a fully automated chemiluminescent immunoassay (CLIA). We evaluated its diagnostic value in sera from patients with several digestive cancers, including hepatocellular carcinoma (HCC), and found serum monomeric Ln-γ2 to be a clinically available biomarker for HCC surveillance. The combination of monomeric Ln-γ2 and prothrombin induced by Vitamin K Absence II (PIVKA-II) may be more sensitive for clinical diagnosis of HCC than any currently used combination.

27 June 2023 in Japanese Journal of Clinical Oncology
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Journal Article
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CKChikatoshi Katada
Chikatoshi Katada
TYTetsuji Yokoyama
Tetsuji Yokoyama
KMKanae Mure
Kanae Mure
HDHisashi Doyama
Hisashi Doyama
HNHiroyoshi Nakanishi
Hiroyoshi Nakanishi
MMManabu Muto
Manabu Muto
Multiple development of esophageal squamous-cell carcinoma is explained by field cancerization and is associated with alcohol consumption and smoking. We investigated the association between the development of second primary esophageal squamous-cell carcinoma after endoscopic resection for esophageal squamous-cell carcinoma and genetic polymorphisms related to alcohol and nicotine metabolism. The study group comprised 56 patients with esophageal squamous-cell carcinoma after endoscopic resection. The main variables were the following: (i) cumulative incidence and total number of second primary esophageal squamous-cell carcinoma according to genetic polymorphisms in alcohol dehydrogenase 1B, aldehyde dehydrogenase 2 and cytochrome P450 2A6; and (ii) risk factors of second primary esophageal squamous-cell carcinoma identified using a multivariate Cox proportional-hazards model. The frequencies of alcohol dehydrogenase 1B, aldehyde dehydrogenase 2 and cytochrome P450 2A6 genetic polymorphisms in the buccal mucosa were analyzed. The median follow-up was 92.8 months (range: 2.7–134.2). Slow-metabolizing alcohol dehydrogenase 1B was associated with a higher 7-year cumulative incidence of second primary esophageal squamous-cell carcinoma (fast-metabolizing alcohol dehydrogenase 1B vs slow-metabolizing alcohol dehydrogenase 1B: 20.5% vs 71.4%, P = 0.006). Slow-metabolizing alcohol dehydrogenase 1B (relative risk [95% confidence interval]: 3.17 [1.49–6.73]), inactive aldehyde dehydrogenase 2 (2.17 [1.01–4.63]) and poorly-metabolizing cytochrome P450 2A6 (4.63 [1.74–12.33]) had a significantly higher total number of second primary esophageal squamous-cell carcinoma per 100 person-years. In the multivariate Cox proportional-hazards model, slow-metabolizing alcohol dehydrogenase 1B was a significant risk factor of the development of second primary esophageal squamous-cell carcinoma (hazard ratio 9.92, 95% confidence interval: 2.35–41.98, P = 0.0018). Slow-metabolizing alcohol dehydrogenase 1B may be a significant risk factor for the development of second primary esophageal squamous-cell carcinoma. In addition, inactive aldehyde dehydrogenase 2 and poorly-metabolizing cytochrome P450 2A6 may be important factors.

30 December 2022 in Life
Verified
Journal Article
Open access
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TMTadateru Maehata
Tadateru Maehata
YSYoshinori Sato
Yoshinori Sato
YNYusuke Nakamoto
Yusuke Nakamoto
MKMasaki Kato
Masaki Kato
AKAkiyo Kawashima
Akiyo Kawashima
KTKeisuke Tateishi
Keisuke Tateishi
Submucosal endoscopy (third-space endoscopy) can be defined as an endoscopic procedure performed in the submucosal space. This procedure is novel and has been utilized for delivery to the submucosal space in a variety of gastrointestinal diseases, such as a tumor, achalasia, gastroparesis, and subepithelial tumors. The main submucosal endoscopy includes peroral endoscopic myotomy, gastric peroral endoscopic myotomy, Zenker peroral endoscopic myotomy, submucosal tunneling for endoscopic resection, and endoscopic submucosal tunnel dissection. Submucosal endoscopy has been used as a viable alternative to surgical techniques because it is minimally invasive in the treatment and diagnosis of gastrointestinal diseases and disorders. However, there is limited evidence to prove this. This article reviews the current applications and evidence regarding submucosal endoscopy while exploring the possible future clinical applications in this field. As our understanding of these procedures improves, the future of submucosal endoscopy could be promising in the fields of diagnostic and therapeutic endoscopy.

15 July 2018 in Turkish Journal of Gastroenterology
Verified
Journal Article
Open access
YMYasumasa Matsuo
Yasumasa Matsuo
HYHiroshi Yasuda
Hiroshi Yasuda
MKMasaki Kato
Masaki Kato
HKHirofumi Kiyokawa
Hirofumi Kiyokawa
MOMidori Ozawa
Midori Ozawa
FIFumio Itoh
Fumio Itoh
Background/Aims: A definitive biopsy-based diagnosis of gastric cancer is sometimes difficult, and some cases are pathologically diagnosed as gastric indefinite neoplasia (GIN). The most appropriate forceps size for gastric biopsy has yet to be determined. In this study, we investigated the relation between the forceps size and the frequency of GIN diagnosis. Materials and Methods: The records of patients from two historical groups were reviewed. The first group comprised patients evaluated during the period when standard biopsy forceps (StF) were used (April 2010-March 2011), and the second group comprised patients evaluated during the period when small biopsy forceps (SmF) were used (April 2011-March 2013). Patients in whom GIN lesions were diagnosed with biopsy were identified, and pertinent data were compared between the two groups of patients. Results: Among the 8,420 patients who underwent esophagogastroduodenoscopy (EGD) during the first period, 2,584 (30.7%) underwent gastric biopsy with StF. Among the 15,968 patients who underwent EGD during the second period, 4,204 (26.3%) underwent gastric biopsy with SmF. GIN was diagnosed in a significantly greater number of patients in the SmF group than in the StF group (52 [1.25%] vs. 19 [0.73%]; p=0.048). The mean minor-axis lengths of the biopsy samples were 1.50±0.50 mm and 1.38±0.40 mm in the StF group and the SmF group, respectively, with the SmF group samples tending to be shorter (p=0.088). Conclusion: Because the SmF use may increase the rate of GIN diagnosis, the use of SmF with a standard-caliber endoscope should be avoided. Cite this article as: Matsuo Y, Yasuda H, Kato M, et al. Endoscopic small-capacity forceps increase the pathological diagnosis of gastric indefinite neoplasia. Turk J Gastroenterol 2018; 29: 481-7.

22 July 2025 in Gastrointestinal Disorders
Verified
Journal Article
Open access
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HYHiroshi Yasuda
Hiroshi Yasuda
TMTadateru Maehata
Tadateru Maehata
YSYoshinori Sato
Yoshinori Sato
HKHirofumi Kiyokawa
Hirofumi Kiyokawa
MKMasaki Kato
Masaki Kato
KTKeisuke Tateishi
Keisuke Tateishi
Objectives: To investigate the real-world outcomes of a population-based gastric cancer (GC) screening program in Kawasaki City, a major urban area with a growing aging population and relatively high screening participation rates. Methods: Between December 2012 and 2021, a total of 337,842 citizens in Kawasaki City underwent population-based GC screening, leading to the detection of 1087 GC cases. Esophageal cancer (EC) has been recorded since 2016, with 236 cases detected. To evaluate the short- and long-term clinical outcomes of screening-detected GC and EC, we conducted a retrospective study using the electronic medical records of patients treated at our hospital, a high-volume institution for GC and EC treatment in the city. As a control group, we included 34 GC and EC cases diagnosed based on symptoms at our hospital in 2018. Results: Among the 1087 GC cases detected through population-based screening, 102 cases treated at our hospital were included in the analysis. Of them, 91 patients (89%) were diagnosed with early-stage GC. All screening-detected GC cases underwent either surgery (27 cases) or endoscopic submucosal dissection (75 cases). The five-year survival rates for GC were 90% in males and 86% in females. Eighteen EC cases were also included in the study. The five-year survival rate for screening-detected advanced GC was 70.0%, while for screening-detected EC, it was 100%. Both survival rates were significantly higher than those for symptom-diagnosed GC (30.0%) and EC (40.8%). Conclusions: The prognosis of GC and EC detected through population-based endoscopic screening is significantly better than that of cancers diagnosed based on symptoms. This underscores the effectiveness of endoscopic screening as a valuable tool for the early detection of upper gastrointestinal tract cancers.

4 June 2025 in Preprints.org
Verified
Preprint
Open access
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HYHiroshi Yasuda
Hiroshi Yasuda
TMTadateru Maehata
Tadateru Maehata
YSYoshinori Sato
Yoshinori Sato
HKHirofumi Kiyokawa
Hirofumi Kiyokawa
MKMasaki Kato
Masaki Kato
KTKeisuke Tateishi
Keisuke Tateishi
Objectives: To investigate the real-world outcomes of a population-based gastric cancer (GC) screening program in Kawasaki City. Methods: A total of 337,842 citizens underwent population-based GC screening in Kawasaki City between December 2012 and 2021, resulting in the detection of 1,087 GC cases. Esophageal cancer (EC) has been recorded since 2016, with 236 cases detected. To evaluate the short- and long-term clinical outcomes of screening-detected GC and EC, we conducted a retrospective study using electronic medical records of patients treated at our hospital which is a high-volume institution for GC and EC treatment in the city. As a control group, we included 34 GC and EC cases diagnosed based on symptoms at our hospital in 2018. Results: Among the 1,087 GC cases detected through population-based screening, 102 cases treated at our hospital were included in the analysis. Of these, 91 patients (89%) were diagnosed with early-stage GC. All screening-detected GC cases underwent either surgery (27 cases) or endoscopic submucosal dissection (75 cases). The five-year survival rates for GC were 90% in males and 86% in females. Eighteen EC cases were also included in our study. The five-year survival rate for screening-detected advanced GC was 70.0%, and for screening-detected EC was 100%, both significantly higher than those for symptom-diagnosed GC (30.0%) and EC (40.8%). Conclusions: The prognosis of GC and EC detected through population-based endoscopic screening is significantly better than that of cancers diagnosed based on symptoms, underscoring the effectiveness of endoscopic screening as a tool for early detection of upper gastrointestinal tract cancers. Keywords: gastric cancer; esophageal cancer; endoscopy; population-based screening