Sachiko Yamamoto

Osaka Medical Center for Cancer and Cardiovascular Diseases, Ōsaka-shi, Osaka-fu, Japan

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Publications (29)104.94 Total impact

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    Article: Delayed perforation: A hazardous complication of endoscopic resection for non-ampullary duodenal neoplasm.
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    ABSTRACT: BACKGROUND: Perforation is a major complication of endoscopic resection for gastrointestinal neoplasms. However, little is known about delayed perforation after endoscopic resection for non-ampullary duodenal neoplasm. The aim of the present study was to investigate the clinical features of delayed perforation after endoscopic resection for non-ampullary duodenal neoplasm. PATIENTS AND METHODS: This was a retrospective cohort study conducted in a referral cancer center. A total of 63 patients (41 with adenomas and 22 with carcinomas) underwent endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) from January 1993 to December 2011. Incidence, outcome, and factors associated with occurrence of delayed perforation were investigated. RESULTS: Delayed perforation occurred in four patients (6.3%). All lesions were located distal to Vater's ampulla. Three of four delayed perforations occurred within 36 h after endoscopic resection. All patients developed retroperitonitis, and two also had retroperitoneal abscesses. Although three patients were cured with conservative management, a long hospital stay was required (28-, 80-, and 81-day hospital stay, respectively). One patient required emergency surgery as a result of panperitonitis. There was, fortunately, no mortality in this series. The significant predictors of delayed perforation were location (distal to Vater's ampulla, P = 0.007) and resection method (ESD and piecemeal EMR, P = 0.003). CONCLUSION: Endoscopic resection for non-ampullary duodenal neoplasms has a possible risk of morbid complication i.e. delayed perforation, especially in patients with lesions located on the side distal from the ampulla and who are treated with piecemeal EMR or ESD.
    Digestive Endoscopy 04/2013; · 1.19 Impact Factor
  • Article: Long-Term Outcome and Metastatic Risk After Endoscopic Resection of Superficial Esophageal Squamous Cell Carcinoma.
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    ABSTRACT: OBJECTIVES:Long-term outcomes after endoscopic resection (ER) provide important information for the treatment of esophageal carcinoma. This study aimed to investigate the rates of survival and metastasis after ER of esophageal carcinoma.METHODS:From 1995 to 2010, 570 patients with esophageal carcinoma were treated by ER. Of these, the 402 patients with squamous cell carcinoma (280 epithelial (EP) or lamina propria (LPM) cancer, 70 muscularis mucosa (MM) cancer, and 52 submucosal (SM) cancer) were included in our analysis. Seventeen patients had cancer invading into the submucosa up to 0.2 mm (SM1) and 35 patients had cancer invading into the submucosa more than 0.2 mm (SM2).RESULTS:The mean (range) follow-up time was 50 (4-187) months. The 5-year overall survival rates of patients with EP/LPM, MM, and SM cancer were 90.5, 71.1, and 70.8%, respectively (P=0.007). Multivariate analysis identified depth of invasion and age as independent predictors of survival, with hazard ratios of 3.6 for MM cancer and 3.2 for SM cancer compared with EP/LPM cancer, and 1.07 per year of age. The cumulative 5-year metastasis rates in patients with EP/LPM, MM, SM1, and SM2 cancer were 0.4, 8.7, 7.7, and 36.2%, respectively (P<0.001). Multivariate analysis identified depth of invasion as an independent risk factor for metastasis, with hazard ratios of 13.1 for MM, 40.2 for SM1, and 196.3 for SM2 cancer compared with EP/LPM cancer. The cumulative 5-year metastasis rates in patients with mucosal cancer with and without lymphovascular involvement were 46.7 and 0.7%, respectively (P<0.0001).CONCLUSIONS:The long-term risk of metastasis after ER was mainly associated with the depth of invasion. This risk should be taken into account when considering the indications for ER.Am J Gastroenterol advance online publication, 12 February 2013; doi:10.1038/ajg.2013.8.
    The American Journal of Gastroenterology 02/2013; · 7.28 Impact Factor
  • Article: Histologic features responsible for brownish epithelium in squamous neoplasia of the esophagus by narrow-band imaging.
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    ABSTRACT: BACKGROUND AND STUDY AIM: Esophageal squamous neoplasias usually appear brown under narrow-band imaging as a result of microvascular proliferation and brownish color changes in the areas between vessels, referred to as brownish epithelium. However, the reasons for the development of this brownish epithelium and its clinical implications have not been fully investigated. METHODS: Patients with superficial esophageal neoplasias treated by endoscopic resection were included in the study. Areas of mucosa with brownish and non-brownish epithelia were evaluated histologically. RESULTS: A total of 68 superficial esophageal neoplasias in 58 patients were included in the analysis. Of the 68 lesions, 32 were classified in the brownish epithelium group, and 36 in the non-brownish epithelium group. Brownish epithelium was significantly associated with a diagnosis of high-grade intraepithelial neoplasia or invasive cancer (P < 0.0001). Thinning of the keratinous layer, thinning of the epithelium, and cellular atypia were significantly associated with brownish epithelium by univariate analysis, and thinning of the keratinous layer and thinning of the epithelium were confirmed to be independent factors by multivariate analysis. The odds ratios were 9.6 (95% confidence interval: 2.0-46.3) for thinning of the keratinous layer and 4.6 (95% confidence interval: 1.1-19.4) for thinning of the epithelium. CONCLUSIONS: Brownish epithelium is an important finding in the diagnosis of esophageal squamous neoplasia, and may be related to thinning of the keratinous layer, caused by neoplastic cell proliferation, and thinning of the epithelium.
    Journal of Gastroenterology and Hepatology 11/2012; · 2.87 Impact Factor
  • Article: Risk factors of chest pain after endoscopic resection of early esophageal cancer.
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    ABSTRACT: Although endoscopic resection is sometimes associated with chest pain, the risk factors for this complication have not been investigated. From January 2003 to December 2007, 241 patients were treated by endoscopic resection and 139 patients who met our criteria were analyzed. The case group was 40 patients who took an analgesic after endoscopic resection because of chest pain. The controls were 79 patients who did not experience chest pain after endoscopic resection. Twenty patients experienced chest pain, but did not take any analgesics. Although, 60 patients (43%) experienced chest pain, this was treatable by a common analgesic. Univariate analysis revealed that female gender had significant association and resection of posterior wall mucosa had marginal association with chest pain and analgesic use. No significant association with chest pain and analgesic use was found for age, resection method, use of acid suppressing drugs, lesion size and site. Logistic-regression analysis showed that significant risk factors for chest pain and analgesic use were female gender (odds ratio 3.45) and resection of posterior wall mucosa (odds ratio 3.13). Female gender and resection of posterior wall mucosa were associated with chest pain and analgesic use after endoscopic resection.
    Hepato-gastroenterology 07/2012; 59(117):1446-9. · 0.66 Impact Factor
  • Article: Safety and curative ability of endoscopic submucosal dissection for superficial esophageal cancers at least 50 mm in diameter.
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    ABSTRACT: Limited data are available regarding the use of endoscopic submucosal dissection (ESD) for superficial esophageal cancers ≥ 50 mm in diameter. The aim of the present study was to investigate the safety and success of ESD for superficial esophageal cancers ≥ 50 mm. A total of 39 patients with superficial esophageal squamous cell carcinoma ≥ 50 mm were treated with ESD at Osaka Medical Center for Cancer and Cardiovascular Diseases between January 2004 and April 2011, and were analyzed in a retrospective study. En bloc resection was achieved in all patients. One mediastinal emphysema without perforation occurred during the procedure. Stricture developed in 11 of 39 patients, requiring a median of five endoscopic balloon dilatation procedures. Thirty-three clinical epithelial or lamina propria mucosal cancers were treated by ESD with curative intent, of which invasion into the muscularis mucosa or deeper was detected in seven and lymphovascular involvement in three. The en bloc resection rate was 100% with a tumor-free margin achieved in 92% of lesions. The curative resection and complication rates during ESD were 70% and 2.5%, respectively. ESD achieved a high en bloc resection rate of 92% with a tumor-free margin. Curative resection rate of ESD in patients with clinical epithelial or lamina propria mucosal cancers was not low at 70%. However, the risk of stricture must be taken into account when considering the use of ESD in lesions ≥ 50 mm.
    Digestive Endoscopy 07/2012; 24(4):220-5. · 1.19 Impact Factor
  • Article: Endoscopic classification of local recurrence after definitive chemoradiotherapy for esophageal squamous cell carcinoma
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    ABSTRACT: BackgroundIt is unknown whether the endoscopic appearance of local recurrent squamous cell esophageal cancer treated with definitive chemoradiotherapy is predictive of the subsequent clinical course. MethodsWe conducted a retrospective review of 19 patients with local recurrence. Local recurrence was classified into three types as seen by endoscopy. Of 19 local recurrences, 9 lesions were classified into superficial type, 7 lesions into submucosal tumor type, and 3 lesions into ulcerative type. The association between the endoscopic appearance of T1 local recurrence (rT1) and its clinical course was then evaluated. ResultsOf 19 local recurrences, 13 were diagnosed as rT1 cancer. Three of nine patients with superficial-type recurrence were treated by surgical resection; the other six patients received endoscopic treatment. One of nine patients with a superficial-type recurrence died of abdominal lymph node recurrence. The other eight patients are alive without further recurrence. All four patients with rT1 submucosal tumor type recurrence received endoscopic treatment. After the diagnosis of local recurrence, lung or abdominal lymph node metastasis developed in three patients and two patients died of their disease. The median survival time for the submucosal tumor type was 26 months; median survival of the superficial type was not reached (P = 0.09). ConclusionsSuperficial-type rT1 recurrence had a good prognosis with a low rate of nonlocal recurrence, whereas submucosal tumor type rT1 recurrence had a relatively high nonlocal recurrence rate and mortality.
    Esophagus 04/2012; 6(4):243-248. · 0.66 Impact Factor
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    Article: Factors predicting perforation during endoscopic submucosal dissection for gastric cancer.
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    ABSTRACT: Perforation is a common complication of endoscopic submucosal dissection (ESD), but little is known about the relevant risk factors. To investigate the risk factors for perforation. Retrospective study. A cancer referral center. A total of 1795 early gastric tumors in 1500 patients treated by ESD from July 2002 to December 2010 were included in the analysis. The associations between the incidence of perforation and patient and lesion characteristics were investigated. Perforation during ESD occurred in 50 lesions (2.8%). Univariate analysis identified tumor location (upper, middle, or lower stomach), tumor diameter (≤ 20 or >20 mm), and treatment period (lesions treated in the first or second period) as predictors of perforation. Multivariate analysis identified tumor location (upper stomach), tumor diameter (>20 mm), and treatment period (first half) as independent risk factors for perforation. The odds ratios were 2.4 (95% CI, 1.3-4.7; P = .006) for lesions in the upper stomach and 1.9 (95% CI, 1.0-3.5; P = .04) for lesions larger than 20 mm. Perforation risks were 5.4% for lesions in the upper stomach and 4.4% for lesions larger than 20 mm. Three patients required emergency surgery, but the rest of the patients were successfully treated with endoscopic clipping. There was no perforation-related mortality. Single-center, retrospective study design. Lesions in the upper stomach and lesions larger than 20 mm were independent risk factors for perforation during ESD. Patients should be made aware of the estimated high risks of these lesions before undergoing ESD.
    Gastrointestinal endoscopy 04/2012; 75(6):1159-65. · 6.71 Impact Factor
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    Article: A water-jet videoendoscope may reduce operation time of endoscopic submucosal dissection for early gastric cancer.
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    ABSTRACT: One of the problems with endoscopic submucosal dissection (ESD) for early gastric cancer is that it prolongs procedure time considerably. The purpose of this study was to investigate whether a videoendoscope with water-jet function shortened the time of ESD for early gastric cancer. A total of 82 early gastric cancers that were intramucosal, differentiated-type adenocarcinoma ≤2 cm, without ulcer or scar, in 75 consecutive patients were investigated. Three supervised resident endoscopists participated as operators. After stratification by the operator and tumor location, the lesions were randomly assigned to the water-jet videoendoscope or a conventional videoendoscope groups. An insulated tipped knife was used for the ESD procedure. Total operation time was evaluated as a primary endpoint. The median (25-75th percentile) total operation time for the water-jet videoendoscope group was 51 (33-87) minutes, which was shorter than the 62 (43-88) minutes for the conventional videoendoscope, but it did not reach significance (P = 0.201). Multivariate analysis revealed that the water-jet videoendoscope (OR 3.0, P = 0.046), tumor size ≤14 mm (OR 3.2, P = 0.040) and antral tumor (OR 4.5, P = 0.046) were significantly associated with short (≤60 min) operation time. The water-jet videoendoscope may reduce operation time of ESD for early gastric cancer, compared with conventional videoendoscope. A large-scale multicenter trial is warranted to clarify the efficacy of the water-jet videoendoscope for gastric ESD.
    Digestive Diseases and Sciences 03/2012; 57(8):2122-9. · 2.12 Impact Factor
  • Article: Comparison between radical esophagectomy and definitive chemoradiotherapy in patients with clinical T1bN0M0 esophageal cancer.
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    ABSTRACT: Esophagectomy remains the mainstay treatment for clinical T1bN0M0 esophageal cancer because pathologic lymph node metastases in these patients are not negligible. Recently, chemoradiotherapy (CRT), which can preserve the esophagus, has been reported to be a promising therapeutic alternative to esophagectomy. However, to our knowledge, no comparative studies of esophagectomy and CRT have been reported in clinical T1bN0M0 esophageal cancer. A total of 173 patients with clinical T1bN0M0 squamous cell carcinoma of the thoracic esophagus were enrolled in this study, 102 of whom were treated with radical esophagectomy (S group) and 71 with definitive CRT (CRT group). Treatment results of both groups were retrospectively compared. No statistically significant difference was found in overall survival, but the S group displayed significantly better progression-free survival than the CRT group. Disease recurrence was observed in 12 S group patients and 20 CRT group patients. The incidence of distant recurrence was similar, while local recurrence and lymph node recurrence were significantly more frequent in the CRT group. In the S group, 20 patients had pathologic lymph node metastasis. The progression-free survival of patients with pathologic lymph node metastasis did not differ from those without nodal metastasis. In the CRT group, local recurrence could be controlled by salvage esophagectomy, but treatment results of lymph node recurrence were poor; only 4 of 12 patients with lymph node recurrences were cured. Selection of patients at high risk of pathologic lymph node metastasis is essential when formulating treatment decisions for clinical T1bN0M0 esophageal cancers.
    Annals of Surgical Oncology 02/2012; 19(7):2135-41. · 4.17 Impact Factor
  • Article: Epstein-Barr virus-associated post-transplant lymphoproliferative disorders after allogeneic peripheral blood stem cell transplantation for Hodgkin-like adult T-cell leukemia/lymphoma.
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    ABSTRACT: A 56-year-old woman with Hodgkin-like adult T-cell leukemia/lymphoma was treated with allogeneic peripheral blood stem cell transplantation on 17 April 2009. She manifested a moderate fever on day 41. CT scanning and other examinations detected slightly swollen lymph nodes, and pathological findings of right axillary lymph nodes revealed an Epstein-Barr virus-associated post-transplant lymphoproliferative disorder. She was successfully treated with rituximab.
    International journal of hematology 12/2011; 95(2):214-6. · 1.17 Impact Factor
  • Article: Autofluorescence imaging endoscopy for screening of esophageal squamous mucosal high-grade neoplasia: a phase II study.
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    ABSTRACT: Few prospective studies examining the efficacy of autofluorescence imaging (AFI) screening for esophageal cancer have been reported. This study aimed to investigate the diagnostic value of AFI endoscopy for the screening of squamous mucosal high-grade neoplasia of the esophagus, performed by experienced and less-experienced endoscopists. Patients with a history of esophageal neoplasia or head and neck cancer underwent AFI endoscopic screening, followed by chromoendoscopy using iodine staining as the reference standard. The primary outcome was the sensitivity of AFI for detecting new squamous mucosal high-grade neoplasias. The secondary outcome was the positive predictive value (PPV) of AFI. Of a total 364 patients who underwent endoscopic examination, 43 new mucosal high-grade neoplasias were detected. The sensitivities of AFI in the experienced and less-experienced endoscopist groups were 71% (95% confidence interval [CI]: 55-87%) and 50% (95% CI: 32-68%), respectively. The PPV of AFI in the experienced and the less-experienced endoscopist groups were 25% (95% CI: 16-34%) and 26% (95% CI: 15-37%), respectively. The sensitivity of AFI in lesions ≤ 10 mm (31%, 5/16 lesions) was significantly lower than that in lesions > 10 mm (78%, 21/27 lesions) (P = 0.003). The sensitivity of AFI for the detection of new squamous mucosal high-grade neoplasias, and its PPV, were both low. Based on these results, a randomized study to compare AFI with standard techniques is not justified.
    Journal of Gastroenterology and Hepatology 07/2011; 27(1):86-90. · 2.87 Impact Factor
  • Article: Predicting the effects of chemoradiotherapy for squamous cell carcinoma of the esophagus by induction chemotherapy response assessed by positron emission tomography: toward PET-response-guided selection of chemoradiotherapy or esophagectomy.
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    ABSTRACT: We have developed a treatment protocol for esophageal cancer involving a single course of induction chemotherapy followed by chemoradiotherapy. This study aimed to determine if it was possible to predict the effects of chemoradiotherapy on the basis of the response to induction chemotherapy, assessed by positron emission tomography (PET). Sixteen patients with Stage II-IVA esophageal cancer were treated using this protocol from April 2007 to July 2010. Chemotherapy involved a fluorouracil and platinum-based combination regimen. All patients received PET scans before and 12-24 days after the beginning of induction chemotherapy. Associations between the response to induction chemotherapy assessed by PET and the effects of chemoradiotherapy were evaluated. Induction chemotherapy followed by chemoradiotherapy resulted in complete response (CR) in 10 of the 16 patients. The reduction in maximum standardized uptake value (SUV(max)) was 58 ± 12% in patients with CR (n = 10), compared with 14 ± 16% in patients without CR (n = 6) (P < 0.0001). Using a cut-off value of 55% for SUV(max) reduction rate, eight of 10 cancers with CR and six of six cancers without CR were correctly identified, providing a sensitivity and specificity of 80 and 100%, respectively. The overall 1-year survival rates for patients with an SUV(max) reduction rate >55% (responders) were 100%, compared with 60% for patients with an SUV(max) reduction rate ≤55% (non-responders), respectively. The response to a single course of induction therapy assessed by PET was significantly associated with the effects of chemoradiotherapy.
    International Journal of Clinical Oncology 07/2011; 17(3):225-32. · 1.41 Impact Factor
  • Article: Comparison between definitive chemoradiotherapy and esophagectomy in patients with clinical stage I esophageal squamous cell carcinoma.
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    ABSTRACT: Chemoradiotherapy (CRT) has been proposed as an alternative therapy to esophagectomy for esophageal cancer, because of its favorable survival rate and mild toxicity. However, no comparative studies of esophagectomy and CRT have been reported in patients with clinical stage I esophageal squamous cell carcinoma. A total of 54 patients with clinical stage I esophageal squamous cell carcinoma were treated with definitive CRT and 116 patients with esophagectomy at Osaka Medical Center for Cancer and Cardiovascular Diseases between 1995 and 2008, and were included in the analysis. Overall survival and recurrence rates were evaluated. Complete follow-up data were available for 169 of the 170 patients (99%). The median (range) observation period was 67 (10-171) months in the esophagectomy group and 30 (4-77) months in the CRT group (P<0.0001). The 1- and 3-year overall survival rates were 97.4% and 85.5%, respectively, in the esophagectomy group and 98.1% and 88.7%, respectively, in the CRT group (P=0.78). Cox proportional hazards modeling showed that the overall survival was comparable between the two groups after adjusting for age, sex, and tumor size. The hazard ratio of CRT for overall survival was 0.95 (95% confidence interval 0.37-2.47). The incidence of local recurrence, including metachronous esophageal cancer, was significantly higher in the CRT group than in the esophagectomy group (P<0.0001). Most local recurrences in the CRT group were intramucosal carcinomas, and were cured after salvage treatment, mainly using endoscopy. The overall survival rate of patients with clinical stage I esophageal cancer treated with CRT was comparable to that in those treated with esophagectomy, despite a high local recurrence rate. Locally recurrent carcinoma was endoscopically treatable in most patients, with no effect on overall survival. CRT seems to be a viable alternative to esophagectomy in patients with clinical stage I esophageal cancer.
    The American Journal of Gastroenterology 02/2011; 106(6):1048-54. · 7.28 Impact Factor
  • Article: Original article: Prospective evaluation of narrow‐band imaging endoscopy for screening of esophageal squamous mucosal high‐grade neoplasia in experienced and less experienced endoscopists
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    ABSTRACT: Narrow-band imaging (NBI) is a novel, noninvasive optical technique that uses reflected light to visualize the organ surface. However, few prospective studies that examine the efficacy of NBI screening for esophageal cancer have been reported. To compare the diagnostic yield of NBI endoscopy for screening of squamous mucosal high-grade neoplasia of the esophagus between experienced and less experienced endoscopists. Patients with a history of esophageal neoplasia or head and neck cancer received NBI endoscopic screening for esophageal neoplasia followed by chromoendoscopy using iodine staining. Biopsy specimens were taken from iodine-unstained lesions and the histological results of mucosal high-grade neoplasias served as the reference standard. The primary outcome was the sensitivity of NBI for detecting new lesions. The secondary outcome was the positive predictive value of NBI and the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of NBI in a per lesion basis. A total of 350 patients (170 by experienced endoscopists and 180 by less experienced endoscopists) underwent endoscopic examination. A total of 42 new mucosal high-grade neoplastic lesions (25 in the experienced endoscopist group and 17 in the less experienced endoscopist group) were detected. In the per-lesion-based analysis, the sensitivity was significantly higher in the experienced endoscopist group (100%; 25/25) compared with the less experienced endoscopist group (53%; 9/17) (P < 0.001). The positive predictive value of NBI was higher in the experienced endoscopist group than in the less experienced endoscopist group (45%, 25/55 vs. 35%, 9/26), although the difference was not significant (P = 0.50). The sensitivity of NBI in the less experienced endoscopist group was 43% in the former half of patients, and increased to 60% in the latter half of patients. In the per-patient-based analysis, the sensitivity of NBI was significantly higher in the experienced endoscopist group (100%) than in the less experienced endoscopist group (100 vs. 69%, respectively; P = 0.04). The positive predictive values of the experienced endoscopist group and the less experienced endoscopist group were similar, and were 48 and 47%, respectively. In conclusion, compared with the gold standard of chromoendoscopy with iodine staining, the sensitivity of NBI for screening of mucosal high-grade neoplasia was 100% with the experienced endoscopists but was low with the less experienced endoscopists. Electronic chromoendoscopy with NBI is a promising screening tool in these high-risk patients with esophageal mucosal high-grade neoplasia, particularly when performed by endoscopists with experience of using NBI.
    Diseases of the Esophagus 08/2010; 23(6):480 - 486. · 1.81 Impact Factor
  • Article: Prospective evaluation of narrow-band imaging endoscopy for screening of esophageal squamous mucosal high-grade neoplasia in experienced and less experienced endoscopists.
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    ABSTRACT: Narrow-band imaging (NBI) is a novel, noninvasive optical technique that uses reflected light to visualize the organ surface. However, few prospective studies that examine the efficacy of NBI screening for esophageal cancer have been reported. To compare the diagnostic yield of NBI endoscopy for screening of squamous mucosal high-grade neoplasia of the esophagus between experienced and less experienced endoscopists. Patients with a history of esophageal neoplasia or head and neck cancer received NBI endoscopic screening for esophageal neoplasia followed by chromoendoscopy using iodine staining. Biopsy specimens were taken from iodine-unstained lesions and the histological results of mucosal high-grade neoplasias served as the reference standard. The primary outcome was the sensitivity of NBI for detecting new lesions. The secondary outcome was the positive predictive value of NBI and the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of NBI in a per lesion basis. A total of 350 patients (170 by experienced endoscopists and 180 by less experienced endoscopists) underwent endoscopic examination. A total of 42 new mucosal high-grade neoplastic lesions (25 in the experienced endoscopist group and 17 in the less experienced endoscopist group) were detected. In the per-lesion-based analysis, the sensitivity was significantly higher in the experienced endoscopist group (100%; 25/25) compared with the less experienced endoscopist group (53%; 9/17) (P < 0.001). The positive predictive value of NBI was higher in the experienced endoscopist group than in the less experienced endoscopist group (45%, 25/55 vs. 35%, 9/26), although the difference was not significant (P = 0.50). The sensitivity of NBI in the less experienced endoscopist group was 43% in the former half of patients, and increased to 60% in the latter half of patients. In the per-patient-based analysis, the sensitivity of NBI was significantly higher in the experienced endoscopist group (100%) than in the less experienced endoscopist group (100 vs. 69%, respectively; P = 0.04). The positive predictive values of the experienced endoscopist group and the less experienced endoscopist group were similar, and were 48 and 47%, respectively. In conclusion, compared with the gold standard of chromoendoscopy with iodine staining, the sensitivity of NBI for screening of mucosal high-grade neoplasia was 100% with the experienced endoscopists but was low with the less experienced endoscopists. Electronic chromoendoscopy with NBI is a promising screening tool in these high-risk patients with esophageal mucosal high-grade neoplasia, particularly when performed by endoscopists with experience of using NBI.
    Diseases of the Esophagus 08/2010; 23(6):480-6. · 1.81 Impact Factor
  • Article: Significance of each narrow-band imaging finding in diagnosing squamous mucosal high-grade neoplasia of the esophagus.
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    ABSTRACT: Although narrow-band imaging (NBI) is used increasingly in clinical situations, the significance of each NBI finding has not been investigated. The primary endpoint of the present study was to identify the significant NBI findings to diagnose esophageal mucosal high-grade neoplasia. Between August 2007 and January 2009, we detected 59 new superficial esophageal lesions. The video images of NBI were recorded digitally. NBI findings such as brownish dots (dilated intra-epithelial papillary capillary loop [IPCL]), tortuous IPCL, elongated IPCL, caliber change in IPCL, variety in IPCL shapes, demarcation line, brownish epithelium, and protrusion or depression were evaluated using the video images. The association between each NBI finding and diagnosis of mucosal high-grade neoplasia, and intra- and interobserver agreement was evaluated. In univariate analysis, brownish epithelium, brownish dots, tortuous IPCL, variety in IPCL shapes and demarcation line were associated significantly with diagnosis of mucosal high-grade neoplasia. In multivariate analysis, brownish epithelium and brownish dots were confirmed to be independent factors. Odds ratios were 25.5 (95% confidence interval [CI]: 2.4-268) for brownish epithelium and 19.3 (95% CI: 1.8-207.7) for brownish dots. Intraobserver agreement was substantial for brownish epithelium and brownish dots. Interobserver agreement was moderate in brownish epithelium and brownish dots. Brownish epithelium and brownish dots were confirmed to be significant and reproducible NBI findings in the diagnosis of squamous mucosal high-grade neoplasia of the esophagus. Initial assessment of esophageal lesions should be done based on these findings.
    Journal of Gastroenterology and Hepatology 08/2010; 25(8):1410-5. · 2.87 Impact Factor
  • Article: In Reply to Dr. Puri et al.
    International journal of radiation oncology, biology, physics 04/2010; · 4.59 Impact Factor
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    Article: Endoscopic submucosal dissection for early gastric cancer performed by supervised residents: assessment of feasibility and learning curve.
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    ABSTRACT: Endoscopic submucosal dissection (ESD) is feasible as a treatment for early gastric cancer (EGC) when it is performed by an experienced endoscopist. We investigated whether it was feasible for novice endoscopists to perform ESD for EGC, and how difficult it was to learn the procedure. This case series study was performed in a cancer referral center. Three resident endoscopists, who had already learned basic procedures, performed ESD under supervision for 30 consecutive lesions, and their procedures were analyzed. The procedure was divided for assessment into (i) mucosal incision and (ii) submucosal dissection by completion of the circumferential mucosal cut. An insulated-tip knife was used for mucosal incision and submucosal dissection. A total of 90 mucosal EGCs (< or = 2 cm) without ulcers or scars in 87 patients were included. Outcomes were: rates of complete resection, complications, and self-completion; operation time; learning curve; and reasons for change of supervisor as an indicator of difficulty. Among the 90 procedures, there was a good overall complete resection rate of 93 %, with an acceptable complication rate of 4.4 %; the complications were delayed hemorrhage in two patients, and perforations in another two patients that were repaired successfully by endoscopic clipping. The self-completion rate and operation time were significantly worse for submucosal dissection than for mucosal incision. Two of the three operators showed a flat learning curve for submucosal dissection. Difficulty with the procedure was related mainly to uncontrollable hemorrhage. With appropriate supervision, gastric ESD by residents is feasible, with equivalent complete resection rates and acceptable complication rates compared with those of experienced endoscopists, although there was difficulty in achieving sufficient self-completion rates in submucosal dissection. Better control of bleeding during submucosal dissection may be a key to improving the procedure.
    Endoscopy 10/2009; 41(11):923-8. · 5.21 Impact Factor
  • Article: Factors predictive of tumor recurrence and survival after initial complete response of esophageal squamous cell carcinoma to definitive chemoradiotherapy.
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    ABSTRACT: To assess factors predictive of recurrent disease and survival after achieving initial complete response (CR) to chemoradiotherapy (CRT) for esophageal cancer. Patients who had clinical Stage I-IVA esophageal cancer and received definitive CRT between 2001 and 2007 were retrospectively analyzed. Of 269 patients with esophageal cancer, 110 who achieved CR after definitive CRT were included in the analyses. Chemoradiotherapy mainly consisted of 2 cycles of cisplatin and fluorouracil with concurrent radiotherapy of 60 Gy in 30 fractions. We identified 28 recurrences and 28 deaths during follow-up. The cumulative 1- and 3-year recurrence rates were 18% and 32%, respectively. By univariate and multivariate analyses, tumor category (hazard ratio [HR] 6.6; 95% confidence interval [CI] 1.4-30.2; p = 0.015) was an independent risk factor for local recurrence, whereas age (HR 3.9; 95% CI 1.1-14.0; p = 0.034) and primary tumor location (HR 4.5; 95% CI 1.6-12.4; p = 0.004) were independent risk factors for regional lymph node or distant recurrences. The cumulative overall 1- and 3-year survival rates were 91% and 66%, respectively. As expected, recurrence was associated with poor survival (p = 0.019). By univariate and multivariate analyses, primary tumor location (HR 3.8; 95% CI 1.2-12.0; p = 0.024) and interval to recurrence (HR 4.3; 95% CI 1.3-14.4; p = 0.018) were independent factors predictive of survival after recurrence. Risk of recurrence after definitive CRT for esophageal cancer was associated with tumor category, age, and primary tumor location; this information may help in improved prognostication for these patients.
    International journal of radiation oncology, biology, physics 05/2009; 76(1):123-9. · 4.59 Impact Factor
  • Article: [The effectiveness of S-1 based sequential chemotherapy as second-line treatment for advanced/recurrent gastric cancer].
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    ABSTRACT: We conducted this study to evaluate the efficacy of S-1 combination chemotherapy as second-line treatment for advanced/recurrent gastric cancer that was resistant to S-1 based chemotherapy as first-line treatment. We evaluated patients included in phase II.III clinical trials, that is SPIRITS trial(S-1 vs CDDP +S-1), GC0301/TOP-002(S-1 vs CPT-11+S-1), OGSG0002(S-1+CPT-11)and OGSG0105(S-1+paclitaxel). Eligibility criteria at first-line included; pathologically proven gastric cancer, adequate bone marrow, hepatic, and renal functions, PS 0-2, no prior therapy, life expectancy estimated > or =12 weeks, age 20-75 years and written informed consent. Endpoints were as follows; )PFS in first-line and second-line, )Time to Second Progression(TSP), 3) OS. Sixty-six patients were evaluable in this study. We classified these patients into 4 groups according to the protocol. A)S-1 alone in first-line and S-1 combination in second-line(n=7), B)S-1 alone in first-line and other drugs in second-line(n=13), C)S-1 combination in first-line and another S-1 combination in second-line(n=33), D) S-1 combination in first-line and other drugs in second-line(n=13). We compared S-1 combination group(A+C)to other drugs group(B+D)in second-line. In first-line, PFS was 157.5 days in group(A+C)and 130 days in group(B +D)(p=0.2749). In second-line, PFS, TSP and OS were as follows; 72.5, 256.5, 473 days in group(A+C)and 56, 201.5, 398.5 days(PFS; p=0.0806, TSP: p=0.0718, OS: p=0.0204)in group(B+D), respectively. With regards to adverse events, group(A+C)in first-line showed higher frequency in grade 3/4 leukopenia(10%), febrile neutropenia(5%)and grade 3 diarrhea(10%)than group(B+D). In second-line, group(B+D)showed grade 3/4 leukopenia (12%)and neutropenia(8%)than group(A+C). There were no treatment-related deaths. These results indicate that S-1 combination chemotherapy is efficient as second-line for advanced/recurrent gastric cancer that got resistant to S-1 based chemotherapy as first-line.
    Gan to kagaku ryoho. Cancer & chemotherapy 03/2009; 36(3):417-24.

Institutions

  • 2006–2013
    • Osaka Medical Center for Cancer and Cardiovascular Diseases
      Ōsaka-shi, Osaka-fu, Japan
  • 2008
    • Osaka City University
      Ōsaka-shi, Osaka-fu, Japan