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Dive into the research topics where Hidemitsu Yasuda is active.

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Featured researches published by Hidemitsu Yasuda.


Gastrointestinal Endoscopy | 2004

Accuracy of linear-array EUS for preoperative staging of gastric cardia cancer

Shouji Shimoyama; Hidemitsu Yasuda; Masanori Hashimoto; Yusuke Tatsutomi; Fumio Aoki; Ken-ichi Mafune; Michio Kaminishi

BACKGROUND The feasibility of a less invasive operation for early stage cancer of the gastric cardia with a low frequency of lymph node involvement has been previously demonstrated by us. Precise discrimination among mucosal, submucosal, and advanced cancers, as well as accurate evaluation of the proximal tumor margin are prerequisites for such stage-specific treatment. EUS is considered the most reliable staging modality. However, there is no EUS study specifically of cardia cancer. METHODS Forty-five patients with gastric cardia cancer who underwent gastrectomy with at least first-tier lymphadenectomy were retrospectively analyzed. The results of preoperative linear-array echoendoscopy (7.5 MHz) with respect to cancer depth, lymph node involvement, and esophageal invasion were compared with postoperative histopathologic findings. RESULTS Overall diagnostic accuracy for depth of invasion was 71%. Sensitivity for T1, T2, and T3 lesions was 100%, 31% and 75%, respectively. Overstaging of T2 cancers was the main diagnostic error. Mucosal (pT1-m) and submucosal (pT1-sm) cancers were correctly discriminated in 81% of patients. Diagnostic accuracy for lymph node involvement was 80%. EUS had positive and negative predictive values of 90% and 80%, respectively, for esophageal invasion. CONCLUSIONS For gastric cardia cancer, the linear-array echoendoscope yielded satisfactory results with respect to depth of invasion, lymph node involvement, and esophageal invasion evaluation. The information obtained is useful to the performance of stage-specific treatment.


World Journal of Surgery | 2005

Concepts, rationale, and current outcomes of less invasive surgical strategies for early gastric cancer: Data from a quarter-century of experience in a single institution

Shouji Shimoyama; Yasuyuki Seto; Hidemitsu Yasuda; Ken-ichi Mafune; Michio Kaminishi

Previously proposed criteria of less invasive surgery for early gastric cancer (EGC) were based mainly on the pathological analyses of the resected specimens; however, preoperative and intraoperative information are also obviously essential for decision making on stage-dependent patient management. Furthermore, most indications and treatment options have not been systematically integrated or evaluated by treatment outcomes. We investigate in this report the rationality of less invasive surgery employed for EGC. Distribution analyses of positive nodes were investigated among 684 patients with primary solitary EGC (379 mucosal and 305 submucosal) who underwent curative resection between 1976 and 2000. Clinicopathological factors highlighted and analyzed included clinical (preoperative and intraoperative) and pathological (postoperative) cancer depth and nodal involvement, gross form, histological type, and maximum cancer diameter, as well as postoperative morbidity and mortality. The scope of lymphadenectomy can be reduced to a modified D1 for clinically mucosal, node-negative, nonpalpable gastric cancer, or for clinically submucosal, node-negative gastric cancer ≤ 1.5 cm for intestinal type, or ≤ 1.0 cm for diffuse type. Otherwise, a modified D2 lymphadenectomy is sufficient. Local resection can be recommended for clinically mucosal, node-negative gastric cancer without apparent ulceration ≤ 4 cm if adjacent lymph nodes are proved cancer negative by a frozen section examination. If the gastric cancer has spread beyond the above criteria, a pylorus-preserving gastrectomy (PPG) can be recommended for tumors located in the middle or lower third of the stomach, provided the distal margin of the cancer is at least 4.5 cm from the pyloric ring. The PPG can be accompanied by a modified D1 or a modified D2 lymphadenectomy according to the respective dissection criteria. Results of these less invasive strategies showed reduced morbidity and mortality, as well as no recurrence or cancer-related deaths. These results suggest that each of our criteria for less invasive surgery for EGC is realistic, well stratified, and satisfactory.


Diseases of The Colon & Rectum | 1998

Peutz-Jeghers syndrome manifesting complete intussusception of the appendix and associated with a focal cancer of the duodenum and a cystadenocarcinoma of the pancreas : Report of a case

Akemi Yoshikawa; Shu Kuramoto; Toshiki Mimura; Kaoru Kobayashi; Shoji Shimoyama; Hidemitsu Yasuda; Michio Kaminishi; Mitsuru Yamakawa; Takeshi Oohara; Toshikazu Murakami

The unusual occurrence of an “inside-out” appendix reported here is a case of complete intussusception of the appendix of a 45-year-old woman with Peutz-Jeghers syndrome in whom the diagnosis of intussusception was made preoperatively. At laparotomy, the lead point of intussusceptum was revealed to be a Peutz-Jeghers syndrome polyp of the appendix. There was also a cystic lesion in the pancreas, and subsequent distal pancreatectomy revealed a cystadenocarcinoma of the pancreas. Two jejunal Peutz-Jeghers syndrome polyps and two duodenal Peutz-Jeghers syndrome polyps were foundvia intraoperative endoscopies. The duodenal polyps were endoscopically removed, whereas a jejunal wedge resection was performed for the adjoining jejunal polyps. One of the two duodenal polyps possessed an adenocarcinoma focus. To our knowledge, this is the first report of complete intussusception of the appendix caused by a Peutz-Jeghers syndrome polyp.


Breast Cancer | 2003

Diabetic mastopathy in an advanced elderly woman with insulindependent type 2 diabetes mellitus

Tetsu Kojima; Makoto Kammori; Masanori Hashimoto; Toshihisa Ogawa; Hidemitsu Yasuda; Yutaka Takazawa; Kaiyo Takubo; Michio Kaminishi

Diabetic mastopathy is an unusual stromal fibrotic lesion, but typically occurs in longstanding insulin dependent and younger diabetic patients. We report a case of diabetic mastopathy in an older diabetic patient. The patient was a 76-year-old woman with a history of type 2 diabetes mellitus for 13 years and 3 years of insulin treatment. She developed a 3 cm, hard, mobile nodule in the left breast. Mammograhy revealed a dense mass. Ultrasonography showed an irregular-shaped hypoechoic lesion with an unclear boundary and acoustic shadowing. Since fine needle aspiration biopsy delivered insufficient material and core needle biopsy did not yield any specific findings for diagnosis, clinically diabetic mastopathy was the prime suspect but breast cancer could be completely ruled out. Surgical excision was thus performed and diabetic mastopathy was confirmed pathologically. We report on this rare case of diabetic mastopathy in a 76 year-old type 2 diabetic patient.


Journal of Surgical Oncology | 2000

Wider indications for the local resection of gastric cancer by adjacent lymphadenectomy.

Shouji Shimoyama; Yasuyuki Seto; Hidemitsu Yasuda; Michio Kaminishi

A variety of minimal invasive treatment strategies for early gastric cancer without reducing the curability have been introduced, however, the indications for the local resection of early gastric cancer have not been precisely established.


Breast Cancer | 2012

Educational program and testing using images for the standardization of breast cancer screening by ultrasonography

Eriko Tohno; Hidehito Takahashi; Takayuki Tamada; Yasuhisa Fujimoto; Hidemitsu Yasuda; Noriaki Ohuchi

BackgroundTo improve the quality of breast cancer screening by ultrasonography, both effective training and evaluation of the performance of the examiners of breast ultrasound are essential.MethodsThe Educational Committee of the Japan Association of Breast and Thyroid Sonology, an NPO, has established 2-day training programs on breast ultrasonography with tests at the end of the programs. The tests are performed using images to evaluate the ability of observers to detect and evaluate lesions on ultrasound. Ability to detect lesions was examined by using videos, and ability to evaluate lesions was examined by using still images. The results of tests taken by 422 physicians and 415 technologists were analyzed.ResultsIn a comparison between physicians and technologists, the video specificity, the still image sensitivity, and the percentage of category agreement did not show any significant differences. The video sensitivity, the still image specificity, and the percentage of disease name agreement were significantly higher in technologists. Observers who had experienced <100 cases showed significantly poorer results in all subjects except for the video specificity in physicians and the still image specificity in technologists.ConclusionsUltrasound technologists perform as well as physicians in recognizing and interpreting cancers on breast ultrasound, which supports their role in performing the initial screening examination.


Annals of Surgical Oncology | 2002

Indications of a minimized scope of lymphadenectomy for submucosal gastric cancer

Shouji Shimoyama; Hidemitsu Yasuda; Ken-ichi Mafune; Michio Kaminishi

BackgroundA recent trend for less invasive surgery has increased consideration for a minimized scope of lymphadenectomy for submucosal cancer; however, feasibility criteria have not been precisely established.MethodsPatterns and sites of nodal involvement were retrospectively investigated in 294 patients with solitary submucosal gastric cancer in association with other clinicopathologic characteristics, including pre- and intraoperative evaluations of cancer depth (cT) and nodal involvement (cN).ResultsAmong the early (cT1) and node-negative (cN0) cancer, intestinal (≤1.5 cm) and diffuse types (<-1.0 cm) of submucosal cancer showed low incidences of nodal involvement (3%) confined to the first tier. When the cancer exceeded these cutoff diameters, positive nodes of the second tier were confined to three priority stations (left gastric, common hepatic, and celiac arteries) at an incidence of 2.3%. Perigastric and preferential dissection of these three node stations (modified D2 dissection) showed survival benefits identical to those of a conventional D2 dissection.ConclusionsWhen submucosal cancer is evaluated as cT1cN0, a virtually sufficient minimized scope of lymphadenectomy is a D1 dissection for that within the cutoff diameter and a modified D2 dissection for that exceeding the cutoff diameter. These two types of dissection can even cover the infrequently observed node-positive stations and can realize no residual disease at surgery.


Journal of Gastroenterology | 1996

Floating gallbladder associated with histologically distinct double cancers

Masao Nakahama; Shu Kuramoto; J. Maeda; Mitsuru Yamakawa; Yoshiaki Jojima; Hirokazu Yamaguchi; Keisuke Kubota; Hidemitsu Yasuda; Tomiko Sasaki; Takeshi Oohara

A case of unusually hypermobile floating gall-bladder in a 79-year-old woman with histologically distinct double cancers of the gallbladder is described. The patient presented with an abdominal cystic mass, which was palpable with easy mobility from the right lower quadrant practically to the left upper quadrant. Exploratory laparotomy was performed and the cystic mass was found to be a floating gallbladder. The cystic duct was elongated and obstructed, and had a long mesentery. After the operation, latent double cancers of the gallbladder were discovered on histopathological examination. The obstruction of the cystic duct was due to chronic inflammation and had resulted in hydrops of the gallbladder. This was suspected to have played an important role in the carcinogenesis. We believe that this is the first report of a floating gallbladder associated with double gallbladder cancers.


Ultrasound in Medicine and Biology | 2017

Ultrasound Image Classification of Ductal Carcinoma In Situ (DCIS) of the Breast: Analysis of 705 DCIS Lesions1

Takanori Watanabe; Takuhiro Yamaguchi; Hiroko Tsunoda; Setsuko Kaoku; Eriko Tohno; Hidemitsu Yasuda; Kanako Ban; Koichi Hirokaga; Kumiko Tanaka; Takeshi Umemoto; Toshitaka Okuno; Yasuhisa Fujimoto; Shuichi Nakatani; Jun Ito; Ei Ueno

The Japan Association of Breast and Thyroid Sonology (JABTS) proposed, in 2003, a conceptual classification system for non-mass abnormalities to be applied in addition to the conventional concept of masses, to facilitate detecting ductal carcinoma in situ (DCIS) lesions. The aim of this study was to confirm the utility of this system and to clarify the distribution of these findings in DCIS lesions. Data on 705 surgically treated DCIS lesions from 16 institutions in Japan were retrospectively reviewed. All 705 DCIS lesions could be classified according to the JABTS classification system. The most frequent findings were hypo-echoic areas in the mammary gland (48.6%), followed by solid masses (28.0%) and duct abnormalities (10.2%) or mixed masses (8.1%). Distortion (1.3%), clustered microcysts (1.4%) and echogenic foci without a hypo-echoic area (2.5%) were uncommon. These results suggest that the concept of non-mass abnormalities is useful in detecting DCIS lesions.


Archive | 2005

Draft Diagnostic Guidelines for Non-Mass Image-Forming Lesions by the Japan Association of Breast and Thyroid Sonology (JABTS) and the Japan Society of Ultrasonics in Medicine

Tokiko Endo; Mitsuhiro Kubota; Yutaka Konishi; Kazuhiro Shimamoto; Kumiko Tanaka; Hiroko Tsunoda-Shimizu; Hideyuki Hashimoto; Norikazu Masuda; Mitsuhiro Mizutani; Isamu Morishima; Hidemitsu Yasuda; Takanori Watanabe; Ei Ueno

We have reported the Diagnostic Guidelines for Non-Mass Image-Forming Lesions. These have been discussed in the subcommittee of the Japan Association of Breast and Thyroid Sonology (JABTS) and the Japan Society of Ultrasonics in Medicine.

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Takanori Watanabe

Fukushima Medical University

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Ei Ueno

University of Tsukuba

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