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Featured researches published by Yamato Ninomiya.


Medicine | 2016

Blood flow speed of the gastric conduit assessed by indocyanine green fluorescence: New predictive evaluation of anastomotic leakage after esophagectomy.

Kazuo Koyanagi; Soji Ozawa; Junya Oguma; Akihito Kazuno; Yasushi Yamazaki; Yamato Ninomiya; Hiroki Ochiai; Yuji Tachimori

AbstractAnastomotic leakage is considered as an independent risk factor for postoperative mortality after esophagectomy, and an insufficient blood flow in the reconstructed conduit may be a risk factor of anastomotic leakage. We investigated the clinical significance of blood flow visualization by indocyanine green (ICG) fluorescence in the gastric conduit as a means of predicting the leakage of esophagogastric anastomosis after esophagectomy.Forty patients who underwent an esophagectomy with gastric conduit reconstruction were prospectively investigated. ICG fluorescence imaging of the gastric conduit was detected by a near-infrared camera system during esophagectomy and correlated with clinical parameters or surgical outcomes.In 25 patients, the flow speed of ICG fluorescence in the gastric conduit wall was simultaneous with that of the greater curvature vessels (simultaneous group), whereas in 15 patients this was slower than that of the greater curvature vessels (delayed group). The reduced speed of ICG fluorescence stream in the gastric conduit wall was associated with intraoperative blood loss (P = 0.008). Although anastomotic leakage was not found in the simultaneous group, it occurred in 7 patients of the delayed group (P < 0.001). A flow speed of ICG fluorescence in the gastric conduit wall of 1.76 cm/s or less was determined by a receiver operating characteristic (ROC) curve, identified as a significant independent predictor of anastomotic leakage after esophagectomy (P = 0.004).This preliminary study demonstrates that intraoperative evaluation of blood flow speed by ICG fluorescence in the gastric conduit wall is a useful means to predict the risk of anastomotic leakage after esophagectomy.


Asian Journal of Endoscopic Surgery | 2017

Laparoscopic mesh repair of adult diaphragmatic hernia: A report of two cases

Junya Oguma; Soji Ozawa; Akihito Kazuno; Miho Nitta; Yamato Ninomiya

Congenital diaphragmatic hernia is very rare in adults. The first choice of treatment is surgery, but the optimal surgical method remains unclear. We performed laparoscopic surgeries for two types of congenital diaphragmatic hernias using a novel mesh coated with a chemically modified substance. The first patient was a 65‐year‐old man with a Bochdalek hernia without a hernial sac, and the other patient was an 80‐year‐old woman with a Morgagni hernia with a hernial sac. The short‐term outcomes of both cases were good, and laparoscopic repair seems to be a useful strategy regardless of the presence or absence of a hernial sac.


World Journal of Surgery | 2018

Clinical Significance of New Magnetic Resonance Thoracic Ductography Before Thoracoscopic Esophagectomy for Esophageal Cancer

Junya Oguma; Soji Ozawa; Akihito Kazuno; Miho Nitta; Yamato Ninomiya; Kentaro Yatabe; Tetsu Niwa; Takakiyo Nomura

BackgroundPreoperative simulation of the thoracic duct using magnetic resonance thoracic ductography (MRTD) would enable a safe lymph node dissection near the thoracic duct and the prevention of chylothorax after an esophagectomy. The aim of this study was to determine whether MRTD is useful for preventing injury to the thoracic duct during surgery and for reducing the incidence of chylothorax after surgery.MethodsWe evaluated 130 patients who underwent preoperative MRTD followed by a thoracoscopic esophagectomy for the treatment of thoracic esophageal cancer between August 2014 and April 2017 (MRTD group). These patients were then compared with 160 patients with esophageal cancer who underwent a thoracoscopic esophagectomy without preoperative MRTD (non-MRTD group).ResultsFour patients in the non-MRTD group developed Type IIIB chylothorax (International Consensus on Standardization), while none of the patients in the MRTD group developed Type III chylothorax. Some type of abnormal finding was found during MRTD in 24 patients (18.5%). Among them, 13 patients (10.0%) exhibited abnormal divergence, which was the most frequent finding, followed by 5 patients (3.8%) with window formation and 2 patients (1.5%) with stitch formation.ConclusionsThe present study revealed the frequencies of abnormal findings of the thoracic duct and of patients with false-negative MRTD findings. Injury to the thoracic duct can be avoided through the use of appropriate care during procedures performed in patients with abnormal findings on preoperative MRTD.


Oncology Letters | 2018

Expression of vasohibin‑1 and ‑2 predicts poor prognosis among patients with squamous cell carcinoma of the esophagus

Yamato Ninomiya; Soji Ozawa; Junya Oguma; Akihito Kazuno; Miho Nitta; Hiroshi Kajiwara; Yasufumi Sato

Vasohibin (VASH) -1 and -2 are novel angiogenic regulators. The aim of the present study was to assess the prognostic values of VASH1 expression and VASH2 expression in esophageal squamous cell carcinoma (ESCC). A total of 209 patients with ESCC were investigated. Resected tumor specimens were immunostained using anti-CD34 antibody, anti-VASH1 antibody and anti-VASH2 antibody. The ratio of the microvessels density and the VASH1 density as the VASH1-positive ratio were defined and the patients were divided into two groups (a high VASH1 group and a low VASH1 group) according to the average value. The patients were also divided into two groups (a high VASH2 group and a low VASH2 group) according to VASH2 expression upon immunostaining. The clinical outcomes of these two groups were then evaluated. The high VASH1 group contained 106 patients (50.7%). The high VASH2 group contained 48 patients (23.0%). Long-term survival was significantly poorer in the high VASH1 group compared with that in the low VASH1 group. A slight correlation between VASH1 expression and VASH2 expression was observed. The low VASH1/low VASH2 group had a better prognosis than the other three groups with different combinations of VASH1 and VASH2 expression levels. The present study showed that high VASH1 expression and high VASH2 expression may be novel independent predictors of a poor prognosis in patients with ESCC and that a slight correlation between VASH1 and VASH2 expression existed. The present findings suggest that combined evaluation of VASH1 and VASH2 expression should provide an improved understanding of their clinicopathological features.


Journal of Thoracic Disease | 2018

Effectiveness of neoadjuvant chemotherapy with etoposide and cisplatin followed by surgery for esophageal neuroendocrine carcinoma: a case report

Miho Yamamoto; Soji Ozawa; Kazuo Koyanagi; Junya Oguma; Akihito Kazuno; Yamato Ninomiya; Kentaro Yatabe; Hiroshi Kajiwara

Patients with esophageal neuroendocrine carcinoma (ENEC), which is a rare disease, are considered to have a poor prognosis because of aggressive progression and widespread dissemination (1). The optimal treatment strategy for ENEC remains to be established. In this report, we describe a patient with ENEC who successfully achieved a pathologically complete response with neoadjuvant chemotherapy.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 2017

Pulmonary artery hypoplasia associated with posterior mediastinal hematoma accompanied by a ruptured pseudoaneurysm of the esophageal branch of the left gastric artery

Miho Nitta; Soji Ozawa; Junya Oguma; Akihito Kazuno; Yamato Ninomiya; Takayuki Nishi; Hideo Shimada; Kazunori Myojin

A 65-year-old woman with no significant medical history visited the emergency department complaining of epigastric discomfort. A computed tomography of the thorax and abdomen showed the attenuation of the pulmonary artery and a posterior mediastinal hematoma. Angiography showed a tortuous esophageal branch of the left gastric artery and a pseudoaneurysm, and during the later phase, the left lower lobe of the lung was enhanced, and finally, the left pulmonary vein was enhanced. We considered that the patient was exhibiting hypoperfusion of the left pulmonary artery arising from left pulmonary artery hypoplasia, since the left lung was supplying the systemic circulation. Transcatheter arterial embolization was performed. The patient has not experienced any recurrence of a ruptured pseudoaneurysm or epigastric discomfort. Here, we report the first documented case of pulmonary artery hypoplasia associated with posterior mediastinal hematoma accompanied by a ruptured aneurysm of the left gastric artery.


Oncology Letters | 2017

Wnt3a expression is associated with poor prognosis of esophageal squamous cell carcinoma

Junya Oguma; Soji Ozawa; Akihito Kazuno; Miho Nitta; Yamato Ninomiya; Hiroshi Kajiwara

The Wnt signaling pathway is widely implicated in various types of cancer. Canonical Wnt signaling, including Wnt3a, may be a key component of cancer progression or chemoresistance. Consequently, it was hypothesized that Wnt3a expression may be a prognostic factor of esophageal squamous cell carcinoma (ESCC) due to its roles in chemoresistance and tumor progression. The aim of the present study was to investigate the association between Wnt3a expression and prognosis in patients with ESCC. Wnt3a expression was evaluated in resected specimens from 139 patients with thoracic ESCC who were subjected to curative surgery without neoadjuvant therapy in Tokai University Hospital between 2007 and 2009. Samples were assessed using immnohistochemistry. Patients with ESCC were divided into two groups according to the expression of Wnt3a in tumor tissue. The influence of Wnt3a expression on clinicopathological findings and prognosis of ESCC were subsequently investigated. Immnohistologically, 68 cases were Wnt3a-positive in the cytoplasm of cancer cells, whereas 71 cases were negative. Multivariate analysis by Cox proportional hazard model showed the association between pN (HR=3.539, P=0.001), venous invasion (HR=2.798, P=0.012), Wnt3a expression (HR=1.691, P=0.046) and overall survival (OS). OS rate and disease-free survival rate were poorer in Wnt3a-positive group compared with those in the Wnt3a-negative group as indicated by the log-rank test (P=0.012 and P=0.023, respectively). In pathological stages I and II, there was no significant difference in the OS rate between Wnt3a-positive and Wnt3a-negative groups; however, the OS rate of the Wnt3a-positive group was significantly worse than that of Wnt3a-negative group in pathological stage III (log rank test; P=0.017). Wnt3a-positive patients with recurrence had a significantly poorer prognosis compared with Wnt3a-negative patients (log-rank test; P=0.023). The present findings suggested that Wnt3a may be a prognostic factor of ESCC.


Esophagus | 2016

Gastrointestinal perforation during neoadjuvant chemotherapy with cisplatin and 5-fluorouracil in patients with esophageal cancer: a report of two cases

Junya Oguma; Soji Ozawa; Akihito Kazuno; Yasushi Yamasaki; Yamato Ninomiya

Neoadjuvant chemotherapy (NAC) followed by surgery is the standard treatment for esophageal squamous cell carcinoma diagnosed as clinical stage II/III in Japan, and the indications for chemotherapy for esophageal cancer are increasing. Here, we report two patients who suffered from upper gastrointestinal perforation during NAC for esophageal cancer. NAC with cisplatin and 5-fluorouracil (CF regimen) was performed for both patients. Emergency operations were performed in all the patients prior to curative surgery for esophageal cancer. Endoscopic examination should be performed to confirm peptic ulcers or scars before NAC with CF regimen, and premedication with a proton pump inhibitor and the avoidance of steroid use are recommended for patients with a history of peptic ulcer to prevent perforation during NAC. Whether the occurrence of perforations during NAC is a risk factor for recurrence or a poor prognosis should be investigated in patients with esophageal cancer.


Clinical Journal of Gastroenterology | 2016

Two-year follow-up period showing the natural history of a superficial esophageal adenocarcinoma arising in a long segment of Barrett’s esophagus

Junya Oguma; Soji Ozawa; Akihito Kazuno; Miho Nitta; Yamato Ninomiya; Sakura Tomita

A 55-year-old woman experienced gastrointestinal dysfunction caused by scleroderma. An initial endoscopy revealed an erosive lesion in a long segment of Barrett’s esophagus, and a biopsy led to a diagnosis of ectopic gastric mucosa. Two years later, an irregular, elevated tumor developed at the same site. This tumor was suspected of having invaded the submucosal layer. A second biopsy led to a diagnosis of adenocarcinoma. The patient subsequently underwent a thoracoscopic esophagectomy. The resected specimen revealed an invasive tumor front that had invaded the deep layer of a duplicated muscularis mucosae. Intraepithelial neoplasia partially surrounded the tumor. This lesion was thought to have developed into an adenocarcinoma according to the orderly sequence of metaplasia, intraepithelial neoplasia and finally adenocarcinoma over a 2-year period. The present case suggests that erosive lesions in Barrett’s esophagus should be strictly followed up by endoscopy, even if a biopsy does not reveal any neoplastic findings.


Journal of Clinical Oncology | 2015

Impact of preoperative neutrophil to lymphocyte ratio on long-term survival in patients with esophageal squamous cell carcinoma.

Kenichi Kamachi; Soji Ozawa; Akihito Kazuno; Hiroyasu Makuuchi; Junya Oguma; Yasusi Yamasaki; Yamato Ninomiya

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