Shinichi Tamura
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Shinichi Tamura has a total of 11 co-authors. Here are the top co-authors by number of shared publications:
- Hidenobu Koga
Clinical Research Support Office, Aso Iizuka Hospital, Iizuka, Japan
3 shared publications - Kazuya Akahoshi
Endoscopy Center, Aso Iizuka Hospital, Iizuka, Japan
3 shared publications - Yoshihiro Ohishi
Department of Pathology, Aso Iizuka Hospital, Iizuka, Japan
3 shared publications - Kento Uemura
Endoscopy Center, Aso Iizuka Hospital, Iizuka, Japan
2 shared publications - Masafumi Oya
Department of Pathology, Aso Iizuka Hospital, Iizuka, Japan
2 shared publications - Reiichi Sashihara
Endoscopy Center, Aso Iizuka Hospital, Iizuka, Japan
2 shared publications
Latest Publications
- 1 January 2026
- Published by Kare Publishing in Diagnostic and Interventional Endoscopy
- Vol. 5 (1) , 1-7
Synchronous Malignancies and Clinicopathologic Features in Patients with Gastric GIST Preoperatively Diagnosed Using Endoscopic Ultrasonography-Guided Fine Needle Aspiration: A Preliminary Retrospective Study
Objective: Gastrointestinal stromal tumors (GISTs) are often reported to coexist with other malignancies, mainly on the basis of postoperative pathological studies for GISTs or other malignancies. This preliminary study aimed to examine the preoperative clinical prevalence of synchronous malignancies and patient and tumoral features in patients with gastric GISTs preoperatively diagnosed using endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). Materials and Methods: 184 patients with gastric GIST diagnosed using preoperative EUS-FNA and postoperative histopathology were analyzed in this retrospective single-center observational study. Staging and assessment for synchronous malignancies was performed using preoperative esophagogastroduodenoscopy (EGD), total colonoscopy (TCS), and computed tomography (CT) of the chest, abdomen, and pelvis. Results: Ten gastric GIST patients had a single synchronous malignancy and two patients harbored two. Two of the 184 patients who underwent EGD exhibited synchronous upper gastrointestinal (GI) malignancy on EGD (1.1%): gastric intramucosal adenocarcinoma in one and superficial esophageal squamous cell carcinoma in the other. Five of the 150 patients who underwent TCS exhibited synchronous lower GI malignancy (3.3%): colorectal adenocarcinoma in three and submucosal carcinoid tumor in two. Extra-GI malignancy was found in a variety of organs in seven of 172 patients who underwent CT (4.1%). Patients with a synchronous malignancy were significantly older than those without (p = 0.02). Conclusion: Preoperative synchronous malignancy is relatively common in patients diagnosed with gastric GIST using EUS-FNA. Preoperative EGD, TCS, and CT of the chest to pelvis are desirable in these patients to assess for synchronous malignancies, as it may affect the treatment plan.
- 1 January 2026
- Published by Kare Publishing in Diagnostic and Interventional Endoscopy
- Vol. 5 (1) , 1-7
Synchronous Malignancies and Clinicopathologic Features in Patients with Gastric GIST Preoperatively Diagnosed Using Endoscopic Ultrasonography-Guided Fine Needle Aspiration: A Preliminary Retrospective Study
Objective: Gastrointestinal stromal tumors (GISTs) are often reported to coexist with other malignancies, mainly on the basis of postoperative pathological studies for GISTs or other malignancies. This preliminary study aimed to examine the preoperative clinical prevalence of synchronous malignancies and patient and tumoral features in patients with gastric GISTs preoperatively diagnosed using endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). Materials and Methods: 184 patients with gastric GIST diagnosed using preoperative EUS-FNA and postoperative histopathology were analyzed in this retrospective single-center observational study. Staging and assessment for synchronous malignancies was performed using preoperative esophagogastroduodenoscopy (EGD), total colonoscopy (TCS), and computed tomography (CT) of the chest, abdomen, and pelvis. Results: Ten gastric GIST patients had a single synchronous malignancy and two patients harbored two. Two of the 184 patients who underwent EGD exhibited synchronous upper gastrointestinal (GI) malignancy on EGD (1.1%): gastric intramucosal adenocarcinoma in one and superficial esophageal squamous cell carcinoma in the other. Five of the 150 patients who underwent TCS exhibited synchronous lower GI malignancy (3.3%): colorectal adenocarcinoma in three and submucosal carcinoid tumor in two. Extra-GI malignancy was found in a variety of organs in seven of 172 patients who underwent CT (4.1%). Patients with a synchronous malignancy were significantly older than those without (p = 0.02). Conclusion: Preoperative synchronous malignancy is relatively common in patients diagnosed with gastric GIST using EUS-FNA. Preoperative EGD, TCS, and CT of the chest to pelvis are desirable in these patients to assess for synchronous malignancies, as it may affect the treatment plan.
- Open Access
- 30 March 2025
- Published by The Korean Society of Gastrointestinal Endoscopy in Clinical Endoscopy
- Vol. 58 (2) , 278-284
Short-term outcome of endoscopic submucosal dissection using a clutch cutter for subepithelial lesions within the esophagogastric submucosa: a Japanese prospective observational study
Background/Aims: The efficacy and safety of endoscopic submucosal dissection using a clutch cutter (ESD-CC) for subepithelial lesions within the esophagogastric submucosa (SELEGSM) has not been investigated. This study aimed to assess the efficacy and safety of ESD-CC for the treatment of SELEGSM.Methods: This prospective study included 15 consecutive patients with 18 SELEGSMs diagnosed by endoscopic ultrasonography. The primary outcomes were short-term outcomes including en bloc resection rate, R0 resection rate, procedure time, and complication rate. The secondary outcome was final histological diagnosis.Results: Among the participants, 18 lesions were identified: 12 in the stomach (nine patients) and six in the esophagus (six patients). The en bloc resection rate was 94.4% (17/18). The R0 resection rate was 88.9% (16/18). The median operating time was 39 min, and no instances of perforation or bleeding were observed. The final diagnoses of SELEGSM included six neuroendocrine tumors (33.3%), six granular cell tumors (33.3%), two ectopic pancreases (11.1%), one inflammatory fibroid polyp (5.6%), one leiomyoma (5.6%), one lipoma (5.6%), and one leiomyosarcoma (5.6%).Conclusions: ESD-CC appears to be a technically efficient and safe approach for SELEGSM resection, suggesting its potential as a valuable treatment option.
- 30 March 2025
- Published by The Korean Society of Gastrointestinal Endoscopy in Clinical Endoscopy
- Vol. 58 (2) , 278-284
Open AccessShort-term outcome of endoscopic submucosal dissection using a clutch cutter for subepithelial lesions within the esophagogastric submucosa: a Japanese prospective observational study
Background/Aims: The efficacy and safety of endoscopic submucosal dissection using a clutch cutter (ESD-CC) for subepithelial lesions within the esophagogastric submucosa (SELEGSM) has not been investigated. This study aimed to assess the efficacy and safety of ESD-CC for the treatment of SELEGSM.Methods: This prospective study included 15 consecutive patients with 18 SELEGSMs diagnosed by endoscopic ultrasonography. The primary outcomes were short-term outcomes including en bloc resection rate, R0 resection rate, procedure time, and complication rate. The secondary outcome was final histological diagnosis.Results: Among the participants, 18 lesions were identified: 12 in the stomach (nine patients) and six in the esophagus (six patients). The en bloc resection rate was 94.4% (17/18). The R0 resection rate was 88.9% (16/18). The median operating time was 39 min, and no instances of perforation or bleeding were observed. The final diagnoses of SELEGSM included six neuroendocrine tumors (33.3%), six granular cell tumors (33.3%), two ectopic pancreases (11.1%), one inflammatory fibroid polyp (5.6%), one leiomyoma (5.6%), one lipoma (5.6%), and one leiomyosarcoma (5.6%).Conclusions: ESD-CC appears to be a technically efficient and safe approach for SELEGSM resection, suggesting its potential as a valuable treatment option.
- Open Access
- 15 November 2023
- Published by AVES YAYINCILIK A.Ş. in Turkish Journal of Gastroenterology
- Vol. 34 (11) , 1156-1162
Endoscopic Ultrasonography-Guided Fine-Needle Aspiration for Duodenal Subepithelial Lesions Showing a Hypoechoic Mass on Endoscopic Ultrasound Imaging
Background/Aims: For duodenal subepithelial lesions showing a hypoechoic mass on endoscopic ultrasound imaging, the utility of endoscopic ultrasound-guided fine-needle aspiration and the frequency of histological types have not been the focus of previous literature. This study aimed to clarify this. Materials and Methods: This prospective observational study enrolled 22 consecutive patients who underwent endoscopic ultrasoundguided fine-needle aspiration for duodenal subepithelial lesions with hypoechoic mass on endoscopic ultrasound. Immunohistochemical analysis was performed for all endoscopic ultrasound-guided fine-needle aspiration and surgically resected specimens. The main outcome measures were the technical results of endoscopic ultrasound-guided fine-needle aspiration and the frequency of histological types of duodenal subepithelial lesions with hypoechoic mass. Results: Thirteen fine-needle aspiration specimens were obtained from the duodenal bulb and eight from the descending duodenal region. The puncture was not performed because of intervening vessels in one patient. The diagnostic rate was 81% (95% confidence interval: 58.1-94.6, 17/21 patients). In 12 patients receiving surgical resection (excluding one cancellation of endoscopic ultrasoundguided fine-needle aspiration), the diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration was 75% (95% confidence interval: 42.8-94.5, 9/12 patients). No complications were observed. The histopathological diagnoses included 11 cases of gastrointestinal stromal tumor (50%), 2 cases of leiomyoma (9%), 2 cases of metastatic cancer (9%), 2 cases of benign inconclusive, and 1 case each of carcinoid, malignant lymphoma, leiomyosarcoma, gauzeoma, and aberrant pancreas (4.5% each). The frequency of malignant tumors in the duodenal subepithelial lesions with hypoechoic mass group was 73% (16/22 patients). Conclusions: Endoscopic ultrasound-guided fine-needle aspiration for duodenal subepithelial lesions with hypoechoic mass was safe and accurate. As duodenal subepithelial lesion with hypoechoic mass has a reasonably high possibility of containing malignant tumors, it is desirable to perform endoscopic ultrasound-guided fine-needle aspiration. Cite this article as: Akahoshi K, Akahoshi K, Shiratsuchi Y, et al. Endoscopic ultrasonography-guided fine-needle aspiration for duodenal subepithelial lesions showing a hypoechoic mass on endoscopic ultrasound imaging. Turk J Gastroenterol. 2023;34(11):1156-1162.
- 15 November 2023
- Published by AVES YAYINCILIK A.Ş. in Turkish Journal of Gastroenterology
- Vol. 34 (11) , 1156-1162
Open AccessEndoscopic Ultrasonography-Guided Fine-Needle Aspiration for Duodenal Subepithelial Lesions Showing a Hypoechoic Mass on Endoscopic Ultrasound Imaging
Background/Aims: For duodenal subepithelial lesions showing a hypoechoic mass on endoscopic ultrasound imaging, the utility of endoscopic ultrasound-guided fine-needle aspiration and the frequency of histological types have not been the focus of previous literature. This study aimed to clarify this. Materials and Methods: This prospective observational study enrolled 22 consecutive patients who underwent endoscopic ultrasoundguided fine-needle aspiration for duodenal subepithelial lesions with hypoechoic mass on endoscopic ultrasound. Immunohistochemical analysis was performed for all endoscopic ultrasound-guided fine-needle aspiration and surgically resected specimens. The main outcome measures were the technical results of endoscopic ultrasound-guided fine-needle aspiration and the frequency of histological types of duodenal subepithelial lesions with hypoechoic mass. Results: Thirteen fine-needle aspiration specimens were obtained from the duodenal bulb and eight from the descending duodenal region. The puncture was not performed because of intervening vessels in one patient. The diagnostic rate was 81% (95% confidence interval: 58.1-94.6, 17/21 patients). In 12 patients receiving surgical resection (excluding one cancellation of endoscopic ultrasoundguided fine-needle aspiration), the diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration was 75% (95% confidence interval: 42.8-94.5, 9/12 patients). No complications were observed. The histopathological diagnoses included 11 cases of gastrointestinal stromal tumor (50%), 2 cases of leiomyoma (9%), 2 cases of metastatic cancer (9%), 2 cases of benign inconclusive, and 1 case each of carcinoid, malignant lymphoma, leiomyosarcoma, gauzeoma, and aberrant pancreas (4.5% each). The frequency of malignant tumors in the duodenal subepithelial lesions with hypoechoic mass group was 73% (16/22 patients). Conclusions: Endoscopic ultrasound-guided fine-needle aspiration for duodenal subepithelial lesions with hypoechoic mass was safe and accurate. As duodenal subepithelial lesion with hypoechoic mass has a reasonably high possibility of containing malignant tumors, it is desirable to perform endoscopic ultrasound-guided fine-needle aspiration. Cite this article as: Akahoshi K, Akahoshi K, Shiratsuchi Y, et al. Endoscopic ultrasonography-guided fine-needle aspiration for duodenal subepithelial lesions showing a hypoechoic mass on endoscopic ultrasound imaging. Turk J Gastroenterol. 2023;34(11):1156-1162.