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Publications (4)11.33 Total impact

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    ABSTRACT: BACKGROUND: In recent years, endoscopic submucosal dissection (ESD) has often been used for the treatment of laterally spreading tumors (LST) of the rectum. The present study was carried out with the aim of clarifying the characteristics of each of the subtypes of LST in the rectum that are often treated by ESD. PATIENTS AND METHODS: This study involved 141 rectal LST that were initially treated at our hospital between March 2005 and December 2010 and whose endoscopic images and histopathological specimens could be re-examined. The LST were divided into LST-G-H (homogeneous type), LST-G-MIX (nodular mixed type), LST-NG-F (flat type) and LST-NG-PD (pseudo-depressed type) type lesions, and tumor diameter and depth of invasion of each of these tumor types were investigated. RESULTS: Regarding the depth of invasion, the proportion of submucosa-massive (SM-m) lesions was high in the LST-NG-PDtumors, even among tumors measuring <20 mm in diameter; both the rate of cancer and proportion of SM-m lesions were significantly higher in the LST-NG-PD tumors than in the LST-NG-F tumors (P < 0.05). In both LST-NG-MIX and LST-NG-PD tumors, the proportion of SM-m lesions was significantly higher in the lower rectum than in the upper rectum (P < 0.05). CONCLUSION: For LST of the rectum (particularly of the lower rectum), it is necessary to carefully select the treatment considering LST subclass and tumor diameter from the standpoint of the presence of malignancy, quality of life, and prognosis of patients.
    Digestive Endoscopy 01/2013; · 1.61 Impact Factor
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    ABSTRACT: BACKGROUND: Early esophagogastric junction (EGJ) cancer is currently being treated in the same way as early gastric cancer, by endoscopic submucosal dissection (ESD), but long-term outcomes are still unknown. Our aim was to retrospectively evaluate the safety and efficacy of ESD in treating early EGJ cancer and compare risk factors in curative and non-curative resection cases. METHODS: Forty-four cases of early EGJ cancer, defined as a Siewert's type II tumor, in 44 patients with a mean age of 70.0 years and a male/female ratio of 90.9:9.1 % were treated by ESD between January 2004 and June 2010. There were 30 standard indication cases; the remaining 14 cases were expanded indication cases. RESULTS: Mean resected specimen and tumor sizes were 35 and 17 mm, respectively, and median procedure time was 121 min, with no bleeding or perforation complications. All cases were resected en bloc with an 84.1 % curative resection rate (37/44). The curative resection rates in the standard and expanded indication cases were 90.0 % (27/30) and 71.4 % (10/14), respectively. There were no significant differences in tumor location, tumor morphology, tumor size, histology of biopsy specimens, or standard versus expanded indication cases with regard to risk factors for curative and non-curative resections. However, submucosal invasion, positive tumor margins, lymphovascular invasion, and some components of poorly differentiated adenocarcinomas in just the submucosal layer were significantly more common in the non-curative resection cases. CONCLUSIONS: ESD was a safe, effective, and minimally invasive treatment for early EGJ cancer. For tumors without any submucosal invasion findings, therefore, ESD is an acceptable treatment option, in addition to also being suitable for diagnostic purposes in evaluating the need for surgery.
    Gastric Cancer 06/2012; · 3.99 Impact Factor
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    ABSTRACT: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are being used increasingly to treat superficial oropharyngeal and hypopharyngeal carcinomas. The aim of this study was to clarify whether ESD provided better results than EMR for en bloc and complete resection of superficial pharyngeal carcinomas. A total of 76 superficial pharyngeal carcinomas in 59 consecutively treated patients were included. Patients underwent either conventional EMR (using a transparent cap or strip biopsy) (n = 45 lesions) or ESD (n = 31 lesions) between October 2006 and January 2011. The rates of en bloc resection, complete resection (defined as en bloc resection with tumor-free margins), major complications, and local recurrence were evaluated retrospectively as the therapeutic outcomes. ESD yielded significantly higher rates of both en bloc and complete resection compared with EMR (en bloc 77.4 % [24/31] vs. 37.8 % [17/45], P = 0.0002; complete 54.8 % [17/31] vs. 28.9 % [13/45], P = 0.0379). ESD was more frequently complicated by severe laryngeal edema (4/21 [19.0 %] vs. 1/31 [3.2 %], P = 0.1446) and was also more time-consuming (124.9 ± 65.1 minutes vs. 57.2 ± 69.6 minutes; P = 0.0014). Local recurrence was observed more often after EMR than after ESD (3/45 [6.7 %] vs. 0/31 [0 %]), although this difference did not reach statistical significance (P = 0.2658). ESD appears to be a superior method of endoscopic resection of superficial pharyngeal carcinomas for achieving both en bloc and complete resection, although these benefits were also associated with a higher incidence of complications and a significantly longer procedure time. Large prospective studies are needed to compare ESD with conventional EMR for superficial pharyngeal carcinomas.
    Endoscopy 06/2012; 44(6):556-64. · 5.74 Impact Factor
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    ABSTRACT: A 73-year-old woman underwent esophagogastroduodenoscopy (EGD) at a local hospital, which revealed a flat elevated lesion, approximately 15 mm in diameter, in the posterior wall of the lower gastric body. At our hospital, a repeat EGD and biopsy led to a diagnosis of moderately dysplastic adenoma. The patient requested endoscopic submucosal dissection (ESD). Histopathology revealed a gastric adenoma with negativity for tumor at the vertical margin; however, the horizontal margin was positive for cancer with an undifferentiated carcinoma surrounding the adenoma. EGD was repeated, and a discolored area was found around the ESD scar. Biopsy revealed an undifferentiated carcinoma. Laparoscopic distal gastrectomy was performed, and postoperative histopathology also revealed an undifferentiated carcinoma (50 mm in diameter) surrounding the ESD scar; this lesion was an undifferentiated adenocarcinoma that was colocalized with and spread out to surround the original adenoma. This case is important for consideration of the pattern of development and progression of superficial spreading gastric cancer.
    Clinical Journal of Gastroenterology 6(3).