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Featured researches published by Mitsuru Ebihara.


Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology | 2008

Dedifferentiated epithelial-myoepithelial carcinoma of the parotid gland: a rare case report of immunohistochemical analysis and review of the literature

Kimihide Kusafuka; Yoshinori Takizawa; Takao Ueno; Hiroto Ishiki; Rie Asano; Tomoyuki Kamijo; Yoshiyuki Iida; Mitsuru Ebihara; Yojiro Ota; Tetsuro Onitsuka; Toru Kameya

Dedifferentiation of salivary gland neoplasms is a rare event, unlike bone and soft part sarcomas, which was first described by Stanley et al. in 1988. An additional case of dedifferentiated epithelial-myoepithelial carcinoma (EMC) is reported here. The patient was a 70-year-old Japanese man who requested examination of the rapid growth of a mass in the right parotid region, which he had first noticed 25 years previously. Clinical examination showed an ill-circumscribed, 6.8 x 4.7 x 7.0-cm lesion. Histologically, most parts of the lesion were high-grade carcinoma (HGC) with sheetlike and nestlike growth of markedly atypical cells and comedonecrosis, whereas the minor part consisted of typical EMC. The outer clear cells of EMC were positive for alpha-smooth muscle actin (ASMA), p63, cytokeratin (CK) 14, and vimentin, and the inner ductal cells of EMC were positive for CKs and epithelial membrane antigen. HGC was negative for ASMA, CK14, and vimentin, but diffusely positive for p53 protein and cyclin D1. The Ki-67 labeling index of EMC was 11.5%, whereas that of HGC was 67.1%. These findings and a review of literature indicate that HGC arose from preexisting EMC, and this phenomenon is the dedifferentiation of EMC. Dedifferentiated EMC is extremely rare.


Japanese Journal of Clinical Oncology | 2013

Mucosal Defect Repair with a Polyglycolic Acid Sheet

Takeshi Shinozaki; Ryuichi Hayashi; Mitsuru Ebihara; Masakazu Miyazaki; Toshifumi Tomioka

OBJECTIVE Early-stage oral or oropharyngeal carcinomas are often treated with surgical resection. Resulting wounds that are too large for primary closure can be covered with skin grafts or patches made from various biomaterials. Recently, polyglycolic acid sheets have been used for this purpose. METHODS We treated six patients with large wounds resulting from the resection of oral or oropharyngeal squamous cell carcinoma by grafting polyglycolic acid sheet patches. All patients were initially treated at the National Cancer Center East Hospital from March 2010 through July 2012. After mucosal resection, the wounds were covered with polyglycolic acid sheet patches attached with fibrin glue. Oral intake was started 4 days after surgery. RESULTS Mucosal resection was the initial treatment in seven patients (five with oral squamous cell carcinoma and two with oropharyngeal squamous cell carcinoma). The polyglycolic acid sheet patches became detached in two patients (on the day of surgery and on postoperative day 6), who then required large doses of analgesics. A patient who underwent tooth extraction also required large doses of analgesics. The other four patients required only small doses of analgesics. One patient had bleeding at the surgical site. No adverse effects were caused by the polyglycolic acid sheet patch or by fibrin glue. CONCLUSIONS Our study has shown that grafting of a polyglycolic acid sheet patch is effective and provides good pain control for patients with large, open wounds after mucosal resection of oral or oropharyngeal squamous cell carcinoma. We plan to evaluate tissue contraction and oral intake after polyglycolic acid patch grafting.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2012

Narrow band imaging endoscopy for unknown primary tumor sites of the neck

Takeshi Shinozaki; Ryuichi Hayashi; Mitsuru Ebihara; Masakazu Miyazaki; Hiroyuki Daiko; Masahisa Saikawa; Satoshi Ebihara

Examinations used to search for unknown primary tumors of squamous cell carcinomas of the neck include CT, MRI, laryngoscopy, gastrointestinal endoscopy, and positron‐emission tomography (PET). Narrow band imaging (NBI) endoscopy in which an optical color‐separation filter is used to narrow the bandwidth of spectral transmittance is also used.


Auris Nasus Larynx | 2011

Window resection of the trachea and secondary reconstruction for invasion by differentiated thyroid carcinoma

Mitsuru Ebihara; Seiji Kishimoto; Ryuichi Hayashi; Masakazu Miyazaki; Takeshi Shinozaki; Hiroyuki Daiko; Masahisa Saikawa; Minoru Sakuraba; Shinpei Miyamoto

OBJECTIVE In cases of differentiated thyroid carcinoma, the presence or absence of invasion into the circumferential organs is an important prognostic factor. Surgical procedures include circular resection of the trachea with end-to-end anastomosis and window resection with secondary closure. We have used window resection with secondary closure since 1993, and herein retrospectively analyze the treatment outcomes for this surgical procedure in order to determine the indications for procedure selection. METHODS Subjects comprised 41 cases of invasion by differentiated thyroid carcinoma into the trachea, for which surgery was performed at the Department of Head and Neck Surgery of the National Cancer Center Hospital East from 1993 to 2007. The mean age was 65.7±7.9 years, and the median length of the observation period was 43 months. There were 17 cases (41.4%) cases of secondary relapse. RESULTS The 5-year and 10-year overall survival rates for this surgical procedure were 78.9% and 74.5%, respectively, while the 5-year and 10-year local control rates were 92.4% and 73.4%, respectively. The pathological resection stump was positive in 27 cases (65.8%), but no significant differences in treatment outcome were observed between the stump-positive group and the stump-negative group. There were 26 cases in which closure of the tracheal fistula was performed by the time of observation. When the tracheal defect had a diameter equivalent to 7 rings of the trachea or less and a circumference half that of the tracheal cartilage or smaller, including partial cricoid cartilage, it was possible to perform closure with only a local flap. For larger defects, reconstruction was performed using hard tissues or materials, such as hydroxyapatite, titanium mesh, and costal cartilage. There were 2 cases that required re-window because of dyspnea after closure. CONCLUSION The treatment outcomes for this surgical procedure for invasive cases of differentiated thyroid carcinoma into the trachea resulted in a low rate of local recurrence and similar survival rates as described in other reports. Even for cases of resection exceeding half the circumference of the trachea, closure of the tracheal fistula can be performed using hard tissues or materials; however, in such cases, we believe that closure should be attempted progressively in a two-stage reconstruction.


Pathology International | 2006

Primary adenoid squamous cell carcinoma of the oral cavity

Kimihde Kusafuka; Mitsuru Ebihara; Hiroto Ishiki; Yoshinori Takizawa; Yoshiyuki Iida; Tetsuro Onitsuka; Reiko Takakuwa; Masako Kasami; Ichiro Ito; Toru Kameya

Adenoid squamous cell carcinoma (ASCC) is an uncommon but well‐recognized variant of squamous cell carcinoma that was first described by Lever in 1947. ASCC has been reported to originate in the sun‐exposed skin of the head and neck and in other sites. An additional case of ASCC is reported here. The patient was a 64‐year‐old Japanese woman who requested examination of a reddish lesion on the left floor of the mouth. The biopsy material was diagnosed as squamous cell carcinoma. Clinical examination showed a well‐circumscribed, 20 × 10 mm‐sized lesion, which was categorized as cT2cN0cm 0. Tumor resection was therefore performed. Histologically, most parts of the lesion were conventional squamous cell carcinoma in situ, but the invasive part consisted of ASCC with gland‐like or reticular appearance. The latter part was negative for mucin staining. Immunohistochemically, this lesion was positive for pancytokeratin, high‐molecular‐weight keratin, cytokeratin (CK) 7/8, CK19, E‐cadherin and p53, but negative for vimentin, CK20, and S‐100 protein. The Ki‐67 labeling index was 50.3% in the ASCC part and 34.5% in the carcinoma in situ part. These findings and a review of the literature indicate that a gland‐like feature of ASCC is associated with the loss of cell adhesion in the center of the cancer nests, and it can be confirmed simply by mucin staining to be neither an adenosquamous carcinoma nor ductal involvement of conventional squamous cell carcinoma.


Virchows Archiv | 2007

Primary nasopharyngeal mucoepidermoid carcinoma in Japanese patients: two case reports with histochemical and immunohistochemical analysis and a review of the literature.

Kimihide Kusafuka; Yoshinori Takizawa; Yoshiyuki Iida; Mitsuru Ebihara; Tetsuro Onitsuka; Toru Kameya

Mucoepidermoid carcinoma is a common neoplasm of the salivary glands. Salivary gland-type neoplasms are very rare in the nasopharynx, and there are only few reports on mucoepidermoid carcinoma of the nasopharynx. Two additional cases of mucoepidermoid carcinoma arising from the nasopharynx are reported here. Case 1: the patient was a 57-year-old Japanese woman who had bloody sputum. Case 2: the patient was a 51-year-old Japanese woman who underwent resection of a nasopharyngeal tumor. Histologically, both tumors were also low-grade mucoepidermoid carcinomas with clear cells. Histochemically, the gland-like nests and mucous cells were positive for mucin staining. Immunohistochemically, the lesions were positive for cytokeratins (CKs), p63, and MUC1, but negative for alpha-smooth muscle actin and EBER mRNA. The Ki-67 labeling indices of the two tumors were 10.4% and 4.3%, respectively. The two present cases and a review of the English literature indicate that salivary gland-type neoplasms arising from the nasopahrynx are extremely rare. The prognosis of salivary gland-type carcinomas of the nasopharynx is still unknown.


Japanese Journal of Clinical Oncology | 2010

The Role of Pulmonary Resection in Tumors Metastatic from Head and Neck Carcinomas

Hiroyuki Daiko; Kanji Nagai; Junji Yoshida; Mitsuyo Nishimura; Tomoyuki Hishida; Mitsuru Ebihara; Masakazu Miyazaki; Takeshi Shinozaki; Shinpei Miyamoto; Minoru Sakuraba; Masahisa Saikawa; Ryuichi Hayashi

OBJECTIVE The purpose of this study was to determine the role of surgical treatment and to identify factors affecting the survival of patients undergoing pulmonary resection for tumors metastatic from head and neck carcinomas. METHODS Thirty-three patients who had undergone resection of pulmonary tumors metastatic from head and neck carcinomas, other than thyroid cancers and sarcomas of the head and neck, were reviewed. RESULTS The operative morbidity rate was only 6%, no patients died within 30 days after resection and complete resection was achieved in 94% of patients. The overall 1- and 3-year survival rates were 76% and 43%, respectively, and the median survival time was 21 months. The factors found on univariate analysis to significantly affect survival were a disease-free interval of < or =2 years, tongue carcinoma and squamous cell carcinoma. The factor found, on multivariate analysis, to most strongly affect survival was tongue carcinoma. The most frequent pattern of initial recurrence after pulmonary resection was distant metastasis (64%). CONCLUSIONS The safety and effectiveness of surgical treatment for pulmonary tumors metastatic from head and neck carcinomas in adaptive criteria for resection are well demonstrated. The poor survival after surgical resection of pulmonary tumors metastatic from cancers of the tongue should be noted.


Archives of Otolaryngology-head & Neck Surgery | 2011

Free Jejunal Patch Graft for Reconstruction After Partial Hypopharyngectomy With Laryngeal Preservation

Shimpei Miyamoto; Minoru Sakuraba; Takayuki Asano; Ryuichi Hayashi; Mitsuru Ebihara; Masakazu Miyazaki; Hiroyuki Daiko; Takeshi Shinozaki; Yoshihiro Kimata

OBJECTIVES To examine postoperative complications and swallowing function associated with free jejunal patch graft transfer after partial hypopharyngectomy with laryngeal preservation. DESIGN Retrospective medical record review. SETTING Academic research. PATIENTS A consecutive series of 43 patients who underwent free jejunal patch graft transfer after partial hypopharyngectomy with laryngeal preservation composed the study sample. They represented the following 3 groups based on the type of hypopharyngeal defect: 13 patients with defects of the posterior wall (PW group), 28 patients with defects extending to the unilateral piriform sinus (PS-PW group), and 2 patients with defects extending to the bilateral piriform sinuses (PS-PS group). MAIN OUTCOME MEASURES Postoperative complications and oral intake ability were compared among the groups. RESULTS Except for 1 patient, all the patients in the PW and PS-PS groups resumed oral intake within 2 weeks after surgery. Four patients in the PS-PW group had severe dysphagia, 2 of whom could not discontinue tube feeding. CONCLUSIONS Free jejunal patch graft transfer after partial hypopharyngectomy allows satisfactory swallowing function, with a low complication rate. Postoperative dysphagia was slightly more common in the PS-PW group than in the PW group.


Japanese Journal of Clinical Oncology | 2013

The Effectiveness of Chemoradiation Therapy and Salvage Surgery for Hypopharyngeal Squamous Cell Carcinoma

Kensuke Suzuki; Ryuichi Hayashi; Mitsuru Ebihara; Masakazu Miyazaki; Takeshi Shinozaki; Hiroyuki Daiko; Minoru Sakuraba; Sadamoto Zenda; Makoto Tahara; Satoshi Fujii

OBJECTIVE The objective of this study was to evaluate the results of salvage surgery after definitive chemoradiation for hypopharyngeal squamous cell carcinoma. METHODS This was a retrospective cohort study. Of the 79 patients with previously untreated hypopharyngeal squamous cell carcinoma who received definitive chemoradiation from January 2004 to January 2009, 24 who had recurrence and underwent salvage surgery at the National Cancer Center Hospital East, Chiba, Japan, were enrolled in this study. RESULTS Of the 24 patients who underwent salvage surgery with curative intent, 13 had an isolated local failure, eight had an isolated neck failure and three had combined local and regional failure. Postoperative surgical complications were observed in eight (33.3%) patients. Of the 24 patients undergoing salvage surgery, 12 (50%) had recurrence. In 11 of these patients, death ensued from salvage failure, defined as the presence of any recurrence after salvage treatment. The causes of cancer-specific death ensuing from salvage failure were regional recurrence of the tumor (n = 6) (one of whom had concurrent distant metastases) and distant metastases alone (n = 5). No local recurrence after salvage surgery was observed in our group of patients. The disease-free and overall 24-month survival rates were 49.0 and 50.0%, respectively. Those patients who initially presented with unresectable disease had lower overall survival compared with those who initially presented with resectable disease (P = 0.0003). CONCLUSIONS The oncologic outcomes were acceptable in those patients in whom salvage surgery was carried out. Those who initially presented with unresectable disease had a poor prognosis.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2008

Alveolar soft part sarcoma of the larynx: A case report of an unusual location with immunohistochemical and ultrastructural analyses

Kimihide Kusafuka; Koji Muramatsu; Tsugumi Yabuzaki; Hiroto Ishiki; Rie Asano; Tomoyuki Kamijo; Yoshiyuki Iida; Mitsuru Ebihara; Testuro Onitsuka; Toru Kameya

Alveolar soft part sarcoma (ASPS) is a rare mesenchymal neoplasm of uncertain origin. In this article, we report a case of ASPS occurring in the larynx, an extremely rare location for this rather unusual tumor.

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Satoshi Ebihara

Osaka Electro-Communication University

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Minoru Sakuraba

Saitama Medical University

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Seiji Kishimoto

Tokyo Medical and Dental University

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