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Dive into the research topics where Kimiyasu Yamazaki is active.

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Featured researches published by Kimiyasu Yamazaki.


Digestive Surgery | 2008

Sentinel Node Mapping Guided by Indocyanine Green Fluorescence Imaging: A New Method for Sentinel Node Navigation Surgery in Gastrointestinal Cancer

Mitsuo Kusano; Yusuke Tajima; Kimiyasu Yamazaki; Masanori Kato; Makoto Watanabe; Mitsuharu Miwa

Background: Recently, gastrointestinal cancer has also been identified as a target for sentinel node navigation surgery (SNNS). This study is the first to determine the feasibility of sentinel node (SN) mapping guided by indocyanine green (ICG) fluorescence imaging in gastrointestinal cancer. Methods: Our series consisted of 22 patients with gastric cancer and 26 patients with colorectal cancer who had undergone standard surgical resection. ICG solution was injected intraoperatively into the subserosa around the tumor. Fluorescence imaging was obtained by a charge-coupled device (CCD) camera with a light-emitting diode with a wavelength of 760 nm as the light source and a cut filter to filter out light with wavelengths below 820 nm as the detector. Results: Immediately after the ICG injection, lymphatic vessels draining the tumor and round-shaped SNs were visualized by their bright fluorescence. Even SNs that were not green in color could be easily and clearly visualized by ICG fluorescence imaging. The SN detection rate and mean number of SNs were 90.9% and 3.6 ± 4.5 (mean ± SD), respectively, in patients with gastric cancer, and 88.5% and 2.6 ± 2.4, respectively, in patients with colorectal cancer. Among the patients with gastric cancer, the accuracy and false-negative rates were 88.9 and 33.3%, respectively, in patients with T1 stage cancer, and 70.0 and 60.0%, respectively, overall, in all the patients. Among the patients with colorectal cancer, the corresponding values were 100 and 0%, respectively, in patients with T1 stage cancer, and 82.6 and 66.7%, respectively, overall, in all the patients. Conclusions: Our preliminary results show that ICG fluorescence imaging allows easy, highly sensitive and real-time imaging-guided SN mapping in patients with gastric or colorectal cancer. SN mapping guided by ICG fluorescence imaging could be a promising tool deserving further clinical exploration.


Annals of Surgery | 2009

Sentinel node mapping guided by indocyanine green fluorescence imaging in gastric cancer.

Yusuke Tajima; Kimiyasu Yamazaki; Yuki Masuda; Masanori Kato; Daisuke Yasuda; Takeshi Aoki; Takashi Kato; Masahiko Murakami; Mitsuharu Miwa; Mitsuo Kusano

Objective:In this study, we determined the possible usefulness of sentinel node (SN) mapping guided by indocyanine green (ICG) fluorescence imaging in the management of gastric cancer. Summary Background Data:ICG fluorescence imaging system has recently been developed for obtaining biochemical information from living tissues. Methods:Our series consisted of 56 patients with gastric cancer who underwent standard gastrectomy with lymphadenectomy. Two milliliters of ICG solution (0.5%) was injected into the submucosa around the tumor endoscopically before the operation or into the subserosa intraoperatively. ICG fluorescence imaging was conducted using a charge-coupled device camera with a light-emitting diode having a wavelength of 760 nm as the light source and a cut filter to filter out light with wavelengths below 820 nm as the detector. Results:SNs were detected in 54 (96.4%) of the 56 patients, and the mean number of SNs was 7.2 ± 7.0. Even SNs that were not green in color could be easily and clearly visualized by ICG fluorescence imaging. cT1-stage cancers were associated with a significantly higher accuracy rate (97.2% vs. 72.2%, P = 0.0127) than cT2-or cT3-stage cancers. Preoperative ICG injection was associated with a significantly higher incidence of cT1-stage cancers (87.1% vs. 40.0%, P = 0.0004), a larger mean number of SNs (9.9 ± 7.5 vs. 4.1 ± 5.0, P < 0.0001), a higher accuracy rate (100% vs. 73.9%, P = 0.0039), and a lower false negative rate (0% vs. 60.0%, P = 0.0345) as compared with intraoperative ICG injection. Conclusions:This study shows that ICG fluorescence imaging allows highly sensitive image-guided intraoperative SN mapping in cases of gastric cancer. Our data suggest that SN mapping guided by ICG fluorescence imaging might be useful for predicting the metastatic status in lymph nodes in cases of gastric cancer, especially those with cT1-stage cancer.


Clinical Cancer Research | 2006

Gastric and Intestinal Phenotypic Marker Expression in Early Differentiated-Type Tumors of the Stomach: Clinicopathologic Significance and Genetic Background

Yusuke Tajima; Kimiyasu Yamazaki; Reiko Makino; Nobukazu Nishino; Shigeo Aoki; Masanori Kato; Koji Morohara; Tsutomu Kaetsu; Mitsuo Kusano

Purpose: Gastric and intestinal phenotypic cell markers are expressed in gastric carcinomas, irrespective of their histologic type. In the present study, we determined the clinicopathologic significance of phenotypic marker expression in early-stage gastric differentiated-type tumors and the association between marker expression and genetic alterations. Experimental Design: Phenotypic marker expression was determined by examining the expressions of human gastric mucin (HGM), MUC6, MUC2, and CD10 in 63 gastric adenomas, 133 early differentiated-type carcinomas, and 24 follow-up cases with gastric adenoma. Tumors were classified into gastric, gastric and intestinal mixed, or intestinal phenotypes according to the immunopositivity of the above markers. The presence of mutations in APC, K-ras, and p53 and the microsatellite instability status were also determined in all tumors. Results: The expressions of HGM and MUC6, representing gastric or gastric and intestinal mixed phenotypes, were significantly associated with high-grade atypia in the 63 gastric adenomas. Among the 133 early differentiated-type carcinomas, HGM expression was significantly associated with mixed-type (with an undifferentiated-type component) tumors and lymph node metastasis. MUC2 expression was inversely associated with submucosal invasion. A multivariate analysis revealed that gastric adenomas were significantly associated with the intestinal phenotype and were inversely associated with p53 mutation compared with early differentiated-type carcinomas. Among all 196 tumors, APC mutation was significantly associated with CD10 expression and the intestinal phenotype and was inversely associated with the expressions of HGM and MUC6. The microsatellite instability status was significantly associated with MUC6 expression. Malignant transformation from gastric adenoma to carcinoma was shown in 5 of the 24 follow-up cases of gastric adenoma. The malignant transformation was significantly associated with the gastric and intestinal mixed phenotype and was inversely associated with APC mutation. No malignant transformation was found in intestinal phenotype gastric adenomas with APC mutation. Conclusions: Our present findings show that phenotypic marker expression is associated with tumor aggressiveness during the early stage of gastric differentiated-type tumors. Differences in the biological behavior of tumors with different phenotypes may result from differences in the genetic backgrounds during the incipient phase of gastric tumorigenesis.


Annals of Surgical Oncology | 2010

Sentinel Node Mapping Guided by Indocyanine Green Fluorescence Imaging During Laparoscopic Surgery in Gastric Cancer

Yusuke Tajima; Masahiko Murakami; Kimiyasu Yamazaki; Yuki Masuda; Masanori Kato; Atsushi Sato; Satoru Goto; Koji Otsuka; Takashi Kato; Mitsuo Kusano

BackgroundIndocyanine green (ICG) fluorescence imaging has recently been reported as a new method for sentinel node (SN) mapping in several types of cancers. In this study, we determined the possible usefulness of SN mapping guided by ICG fluorescence imaging during laparoscopy-assisted gastrectomy (LAG) for gastric cancer.MethodsOur series consisted of 77 patients with cT1- or cT2-stage gastric cancer who had undergone LAG (LAG group; 38 patients) or conventional open gastrectomy (OG group; 39 patients). Intraoperative SN mapping guided by ICG fluorescence imaging was conducted with a charge-coupled device camera with a light-emitting diode as the light source and a cut filter as the detector.ResultsThe detection rate and mean number of fluorescent nodes (FNs) were 94.7% and 7.9, respectively, in the LAG group, and 94.9% and 7.2, respectively, in the OG group. The accuracy and false-negative rates were 97.2% (35 of 36 cases) and 25% (1 of 4), respectively, in the LAG group, and 91.9% (34 of 37) and 23.1% (3 of 13), respectively, in the OG group. Among 33 LAG group patients and 27 OG group patients without FN metastasis, lymph node metastasis was found only in non-SNs located in the same lymphatic basin as the detected FNs.ConclusionsSN mapping guidance by ICG fluorescence imaging could be useful for predicting the lymph node metastasis in gastric cancer, even during LAG. Our data suggest that dissection of the lymphatic basin containing FNs with laparoscopic surgery may be a promising approach as a new type of minimally invasive surgery for patients with cT1- or cT2-stage gastric cancer having no metastasis in FNs.


British Journal of Cancer | 2004

Gastric and intestinal phenotypic marker expression in gastric carcinomas and recurrence pattern after surgery-immunohistochemical analysis of 213 lesions-

Yusuke Tajima; Kimiyasu Yamazaki; Nobukazu Nishino; Koji Morohara; T Yamazaki; T Kaetsu; S Suzuki; M Kawamura; K Kumagai; Mitsuo Kusano

Both gastric and intestinal phenotypic markers are known to be expressed in gastric carcinomas, irrespective of their histologic type. In the present study, the relation between gastric and intestinal phenotypic marker expression in gastric carcinomas and the recurrence pattern after surgery was examined. The phenotypic marker expression of the tumour was determined by examining the expression of human gastric mucin (HGM), MUC6, MUC2 and CD10 in 213 advanced gastric carcinomas in 213 patients who had undergone a curative resection (97 died from recurrent gastric carcinoma and 116 were alive without recurrence at the end of the follow-up period). Tumours were classified into gastric (G), gastric and intestinal mixed (GI), intestinal (I) or unclassified (UC) phenotypes according to the immunopositivity of HGM, MUC6, MUC2 and CD10 stainings. The incidence of HGM-positive tumours and MUC2-negative tumours was significantly higher in tumours with peritoneal recurrence than in tumours without recurrence (73.3%, 44 out of 60 cases vs 54.3%, 63 out of 116 (P=0.022); and 70.0%, 42 out of 60 vs 38.8%, 45 out of 116 (P=0.0002), respectively). The incidence of G-phenotype tumours was also significantly higher in tumours with peritoneal recurrence than in tumours without recurrence (58.3%, 35 out of 60 cases vs 28.4%, 33 out of 116 (P=0.0002)). The incidence of MUC2-negative tumours and CD10-positive tumours was significantly higher in tumours with haematogenous recurrence than in tumours without recurrence (62.5%, 20 out of 32 cases vs 38.8%, 45 out of 116 (P=0.028); and 43.8%, 14 out of 32 vs 23.3%, 27 out of 116 (P=0.039); respectively). Our present findings show that the gastric and intestinal phenotypic marker expression of the tumour, determined by immunohistochemical staining for HGM, MUC6, MUC2 and CD10, can be used to predict the pattern of gastric carcinoma recurrence after curative resection.


British Journal of Cancer | 2007

Differences in the histological findings, phenotypic marker expressions and genetic alterations between adenocarcinoma of the gastric cardia and distal stomach

Yusuke Tajima; Kimiyasu Yamazaki; Reiko Makino; Nobukazu Nishino; Yuki Masuda; Shigeo Aoki; Masanori Kato; Koji Morohara; Mitsuo Kusano

Adenocarcinoma of the gastric cardia (C-Ca) is possibly a specific subtype of gastric carcinoma. The purpose of this study was to clarify the differences in the clinicopathological characteristics between C-Ca and adenocarcinoma of the distal stomach (D-Ca), and also the differences in the expressions of gastric and intestinal phenotypic markers and genetic alterations between the two. The clinicopathological findings in 72 cases with C-Ca were examined and compared with those in 170 cases with D-Ca. The phenotypic marker expressions examined were those of human gastric mucin (HGM), MUC6, MUC2 and CD10. Furthermore, the presence of mutations in the APC, K-ras and p53 genes and the microsatellite instability status of the tumour were also determined. C-Ca was associated with a significantly higher incidence of differentiated-type tumours and lymphatic vessel invasion (LVI) as compared with D-Ca (72.2 vs 48.2%, P=0.0006 and 72.2 vs 55.3%, P=0.0232, respectively). Oesophageal invasion by the tumour beyond the oesophago-gastric junction (OGJ) was found in 56.9% of cases with C-Ca; LVI in the area of oesophageal invasion was demonstrated in 61% of these cases. Also, LVI was found more frequently in cases of C-Ca with oesophageal invasion than in those without oesophageal invasion (82.9 vs 58.1%, P=0.0197). The incidence of undifferentiated-type tumours was significantly higher in cases with advanced-stage C-Ca than in those with early-stage C-Ca (5 vs 36.5%, P=0.0076). A significantly greater frequency of HGM expression in early-stage C-Ca and significantly lower frequency of MUC2 expression in advanced-stage C-Ca was observed as compared with the corresponding values in cases of D-Ca (78.9 vs 52.2%, P=0.0402 and 51.5 vs 84.6%, P=0.0247, respectively). Mutation of the APC gene was found in only one of all cases of C-Ca, and the frequency of mutation of the APC gene was significantly lower in cases of C-Ca than in those of D-Ca (2.4 vs 20.0%, P=0.0108). The observations in this study suggest that C-Ca is a more aggressive tumour than D-Ca. The differences in biological behavior between C-Ca and D-Ca may result from the different histological findings in the wall of the OGJ and the different genetic pathways involved in the carcinogenesis.


Journal of Cancer Research and Clinical Oncology | 2006

Gastric and intestinal phenotypic cell marker expressions in gastric differentiated-type carcinomas: association with E-cadherin expression and chromosomal changes

Koji Morohara; Yusuke Tajima; Kentaro Nakao; Nobukazu Nishino; Shigeo Aoki; Masanori Kato; Masaaki Sakamoto; Kimiyasu Yamazaki; Tsutomu Kaetsu; Satoshi Suzuki; Akira Tsunoda; Tetsuhiko Tachikawa; Mitsuo Kusano

AbstractsGastric and intestinal phenotypic cell markers are widely expressed in gastric carcinomas, irrespective of their histological type. In the present study, the relations between the phenotypic marker expression of the tumour, histological findings, expression of cell adhesion molecules, and the chromosomal changes in gastric differentiated-type carcinomas were examined. The phenotypic marker expression of the tumour was determined by the combination of the expression of the human gastric mucin (HGM), MUC6, MUC2 and CD10, and was evaluated in comparison with the expression of cell adhesion molecules, such as E-cadherin and β-catenin, and chromosomal changes by comparative genomic hybridization (CGH) in 34 gastric differentiated-type carcinomas. Tumours were classified into the gastric- (G-), gastric and intestinal mixed- (GI-), intestinal- (I-), or unclassified- (UC-) phenotype according to the immunopositivity of staining for HGM, MUC6, MUC2, and CD10. G-phenotype tumours were significantly associated with a higher incidence of differentiated-type tumours mixed with undifferentiated-type component, compared with GI- and I-phenotype tumours (88.9 vs 33.3%, P=0.0498 and 88.9 vs 42.9%, P=0.0397; respectively). HGM-positive tumours were significantly associated with a higher incidence of tumours with abnormal expression of E-cadherin, compared with HGM-negative tumours (66.7 vs 21.1%, P=0.0135). GI-phenotype tumours were significantly associated with a higher incidence of tumours with abnormal expression of E-cadherin, compared with I-phenotype tumours (77.8 vs 21.4%, P=0.0131). HGM-negative tumours were significantly associated with higher frequencies of the gains of 19q13.2 and 19q13.3, compared with HGM-positive tumours (57.9 vs 20.0%, P=0.0382 and 63.2 vs 13.3%, P=0.0051; respectively). MUC6-positive tumours were significantly associated with higher frequencies of the gains of 20q13.2, compared with MUC6-negative tumours (71.4 vs 30.0%, P=0.0349). MUC2-positive tumours were significantly associated with the gain of 19p13.3, compared with MUC2-negative tumours (41.2 vs 5.9%, P=0.0391). I-phenotype tumours were significantly associated with higher frequencies of gains of 5p15.2 and 13q33-34, compared with G-phenotype tumours (66.7 vs 0%, P=0.0481, each) and also associated with higher frequencies of gain of 7p21, compared with GI-phenotype tumours (66.7 vs 0%, P=0.0481). Our present results show that gastric differentiated-type carcinomas have different characteristics according to the phenotypic marker expression of the tumour in terms of histological findings, E-cadherin expression and pattern of chromosomal changes.


The Scientific World Journal | 2014

Feasibility of Endoscopy-Assisted Laparoscopic Full-Thickness Resection for Superficial Duodenal Neoplasms

Ken Ohata; Masahiko Murakami; Kimiyasu Yamazaki; Kouichi Nonaka; Nobutsugu Misumi; Tomoaki Tashima; Yohei Minato; Meiko Shozushima; Takahiro Mitsui; Nobuyuki Matsuhashi; Kuangi Fu

Background. Superficial duodenal neoplasms (SDNs) are a challenging target in the digestive tract. Surgical resection is invasive, and it is difficult to determine the site and extent of the lesion from outside the intestine and resect it locally. Endoscopic submucosal dissection (ESD) has scarcely been utilized in the treatment of duodenal tumors because of technical difficulties and possible delayed perforation due to the action of digestive juices. Thus, no standard treatments for SDNs have been established. To challenge this issue, we elaborated endoscopy-assisted laparoscopic full-thickness resection (EALFTR) and analyzed its feasibility and safety. Methods. Twenty-four SDNs in 22 consecutive patients treated by EALFTR between January 2011 and July 2012 were analyzed retrospectively. Results. All lesions were removed en bloc. The lateral and vertical margins of the specimens were negative for tumor cells in all cases. The mean sizes of the resected specimens and lesions were 28.9 mm (SD ± 10.5) and 13.3 mm (SD ± 11.6), respectively. The mean operation time and intraoperative estimated blood loss were 133 min (SD ± 45.2) and 16 ml (SD ± 21.1), respectively. Anastomotic leakage occurred in three patients (13.6%) postoperatively, but all were minor leakage and recovered conservatively. Anastomotic stenosis or bleeding did not occur. Conclusions. EALFTR can be a safe and minimally invasive treatment option for SDNs. However, the number of cases in this study was small, and further accumulations of cases and investigation are necessary.


Journal of surgical case reports | 2017

A long-term survival case after surgical resection of skeletal muscle metastasis following esophagectomy for squamous cell carcinoma of the esophagus

Akira Saito; Masahiko Murakami; Koji Otsuka; Masahiro Komoto; Rei Kato; Kentaro Motegi; Takeshi Yamashita; Hiromi Date; Tomotake Ariyoshi; Satoru Goto; Tomotake Koizumi; Kimiyasu Yamazaki; Makoto Watanabe; Takeshi Aoki

Abstract Cases of skeletal muscle metastasis of esophageal carcinoma are very rare, with few reports of long-term survival. We report a case of long-term survival after surgical resection of skeletal muscle metastasis. A 56-year-old man with advanced esophageal cancer and early gastric cancer underwent thoracoscopic esophagectomy, 2-field lymph node dissection, partial gastrectomy and gastric tube reconstruction. Six months later, cervical lymph node metastasis and mediastinal lymph node recurrence were found. Therefore, the patient underwent cervical lymph node dissection and adjuvant chemoradiotherapy. Two years and 3 months after the esophagectomy, a muscle metastasis was found in the left shoulder, and he underwent tumor dissection, followed by adjuvant chemotherapy for a year. There has been no sign of recurrence since, even 13 years after the esophagectomy. We believe our aggressive surgical treatment might have led to long-term survival.


Case Reports in Gastroenterology | 2016

Intrathoracic Hernia after Total Gastrectomy.

Yoshihiko Tashiro; Masahiko Murakami; Koji Otsuka; Kazuhiko Saito; Akira Saito; Kentaro Motegi; Hiromi Date; Takeshi Yamashita; Tomotake Ariyoshi; Satoru Goto; Kimiyasu Yamazaki; Akira Fujimori; Makoto Watanabe; Takeshi Aoki

Intrathoracic hernias after total gastrectomy are rare. We report the case of a 78-year-old man who underwent total gastrectomy with antecolic Roux-Y reconstruction for residual gastric cancer. He had alcoholic liver cirrhosis and received radical laparoscopic proximal gastrectomy for gastric cancer 3 years ago. Early gastric cancer in the remnant stomach was found by routine upper gastrointestinal endoscopy. We initially performed endoscopic submucosal dissection, but the vertical margin was positive in a pathological result. We performed total gastrectomy with antecolic Roux-Y reconstruction by laparotomy. For adhesion of the esophageal hiatus, the left chest was connected with the abdominal cavity. A pleural defect was not repaired. Two days after the operation, the patient was suspected of having intrathoracic hernia by chest X-rays. Computed tomography showed that the transverse colon and Roux limb were incarcerated in the left thoracic cavity. He was diagnosed with intrathoracic hernia, and emergency reduction and repair were performed. Operative findings showed that the Roux limb and transverse colon were incarcerated in the thoracic cavity. After reduction, the orifice of the hernia was closed by suturing the crus of the diaphragm with the ligament of the jejunum and omentum. After the second operation, he experienced anastomotic leakage and left pyothorax. Anastomotic leakage was improved with conservative therapy and he was discharged 76 days after the second operation.

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