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Dive into the research topics where Ryo-ichi Yoshimura is active.

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Featured researches published by Ryo-ichi Yoshimura.


Journal of Magnetic Resonance Imaging | 2001

Relationship between bone marrow cellularity and apparent diffusion coefficient.

Yoshie Nonomura; Mayumi Yasumoto; Ryo-ichi Yoshimura; Kyoko Haraguchi; Sukeyuki Ito; Takumi Akashi; Isamu Ohashi

This study was performed to determine if there is a relationship between apparent diffusion coefficient (ADC) and cellularity of bone marrow of the posterior ilium. Four groups of various marrow cellularity underwent diffusion‐weighted echo‐planar imaging: 1) adults with normal hypocellularity (21 patients); 2) adults with normal normocellularity (13 patients); 3) young children with normal hypercellularity (5 patients); and 4) adults with lymphoma‐related hypercellularity (3 patients). In all adults, marrow cellularity was confirmed by uni‐or bilateral bone marrow biopsies. In children, the iliac marrow was presumed hypercellular because of their ages. A total of 66 ADC values of bone marrow calculated from diffusion‐weighted images with b‐values of 30 and 300 seconds/mm2 was evaluated. Hypercellular marrow (normal and lymphoma‐related) showed the highest mean ADC, and hypocellular the lowest ADC. Statistically significant differences were found between three groups of normal marrow: hypocellular, normocellular, and hypercellular. There is a positive correlation between ADC and cellularity of bone marrow. J. Magn. Reson. Imaging 2001;13:757–760.


Cancer | 2002

Site specific dependency of second primary cancer in early stage head and neck squamous cell carcinoma

Eiji Yamamoto; Hitoshi Shibuya; Ryo-ichi Yoshimura; Masahiko Miura

A study was conducted to determine the site specificity of second primary cancer (SPC) following early (Stage I and II) squamous cell carcinoma of the head and neck (SCH) and its impact on prognosis.


Radiotherapy and Oncology | 2003

Neck node metastasis after successful brachytherapy for early stage tongue carcinoma

Tsuneaki Nakagawa; Hitoshi Shibuya; Ryo-ichi Yoshimura; Masahiko Miura; Norihiko Okada; Seiji Kishimoto; Mitsuo Amagasa; Ken Omura

BACKGROUND AND PURPOSE The accuracy of factors for predicting lymph node metastasis in patients with early-stage (stage I and II) mobile tongue carcinoma and prognostic factors associated with the clinical and pathological findings of lymph node metastasis were examined. MATERIAL AND METHODS Between 1971 and 1998, 616 patients with early stage mobile tongue carcinoma were treated by brachytherapy with or without external irradiation. Neck lymph node metastasis occurred in a total of 237 cases, and 191 of them were not associated with primary failure. Neck dissection was performed in 169 of these 191 cases, and 16 cases were treated by radiotherapy. A pathological analysis was possible in 159 of the 169 neck dissection cases. RESULTS There were 88 tongue cancer recurrences, and the incidence of neck metastasis was 38% (191/528) in the cases of primary controlled early tongue carcinoma, and 25% (38/151) and 41% (153/377), in stage-I and -II carcinoma, respectively. Neck metastasis was diagnosed within 12 months in 80% of cases, and within 24 months in 95%. Macroscopic appearance, tumor thickness and tumor length were identified as significant risk factors by a univariate analysis, but macroscopic appearance was the only significant risk factor identified by a multivariate analysis (P<0.001). The incidence of cervical lymph node metastasis was 62% among the invasive/ulcerative type tongue carcinomas, and was lower among the superficial type and exophytic/nodular type (20 and 35%, respectively). Regional and/or distant failure occurred in 75 of the 169 neck dissection cases (44%). The incidence of regional/distant failure was extremely high (49/68=72%) in the extra-nodal invasion group, and extra-nodal invasion was found even in small metastatic node less than 1 cm in length (20%). CONCLUSIONS The macroscopic appearance of the primary tongue carcinoma has a major impact on the incidence of lymph node metastasis in patients with early tongue cancer, and extra-nodal invasion was the dominant risk factor for regional and distant failure. Treatment policy for clinically negative neck metastasis in early tongue cancer patients should be determined after considering the possibility of neck metastases and the morbidity associated with elective neck dissection.


International Journal of Radiation Oncology Biology Physics | 2002

TRIMODAL COMBINATION THERAPY FOR MAXILLARY SINUS CARCINOMA

Ryo-ichi Yoshimura; Hitoshi Shibuya; Ichiro Ogura; Masahiko Miura; Teruo Amagasa; Shoji Enomoto; Seiji Kishimoto

PURPOSE This study was conducted to evaluate the effectiveness of trimodal combination therapy (radiotherapy, intra-arterial chemotherapy, antrotomy) for the treatment of primary maxillary sinus carcinoma. METHODS AND MATERIALS Between 1977 and 1996, 110 patients with maxillary squamous cell carcinoma were treated with trimodal combination therapy at Tokyo Medical and Dental University Hospital. All tumors were classified according to the 1997 UICC TNM staging system. Eighty percent of patients had T3 or T4 tumors. The T3 and T4 tumors were also classified into three groups according to their location, as visualized using computed tomography: the posterior-lateral (P) group, the medial (M) group, and the upper (U) group. Eight patients received additional radiotherapy, and 37 patients underwent a second surgical procedure, in addition to the trimodal combination therapy. RESULTS The 5-year cause-specific survival and local control rates were 71% and 65%, respectively. The 5-year local control rate was 80% for the T1+2 tumors, 64% for the T3 tumors, and 52% for the T4 tumors (p = 0.06). Patients in the P+M group who received a 5-fluorouracil (5-FU) dosage of more than 3500 mg had a better 5-year local control rate than patients who received a 5-FU dosage of less than 3500 mg (p = 0.01). No improvement in the local control rate after a second surgical procedure or additional irradiation treatment was observed in any of the groups. CONCLUSION Trimodal combination therapy provides good local control, with the final outcome depending on the T stage of the tumor and the dosage of 5-FU.


International Journal of Radiation Oncology Biology Physics | 2009

QUALITY OF LIFE OF ORAL CANCER PATIENTS AFTER LOW-DOSE-RATE INTERSTITIAL BRACHYTHERAPY

Ryo-ichi Yoshimura; Hitoshi Shibuya; Masahiko Miura; Hiroshi Watanabe; Fumio Ayukawa; Keiji Hayashi; Kazuma Toda

PURPOSE To assess the quality of life (QOL) of oral cancer patients treated with low-dose-rate interstitial brachytherapy (LDR-BT) alone. METHODS AND MATERIALS Between June 2005 and July 2006, a total of 56 patients with oral cancer were enrolled in this prospective study. QOL was assessed by means of the core questionnaire and head and neck questionnaire module of the European Organization for Research and Treatment of Cancer (EORTC Quality of Life Questionnaire-Core 30 [QLQ-C30] and QLQ Head and Neck 35 [H&N35]). The questionnaires were distributed to the patients before the start of treatment and 3 months, 6 months, and 12 months after the start of LDR-BT. RESULTS It was possible to analyze the results for 20 of the initial 56 patients because they did not experience metastasis or recurrence during this study. No functions or symptoms asked about in the QLQ-C30 deteriorated during the first year. The emotional function score steadily and significantly increased. No symptoms in the QLQ-H&N35 significantly deteriorated. The scores for pain, trouble with social eating, and weight loss on the QLQ-H&N35 steadily and significantly decreased. Age, gender, and LDR-BT source had no effect on the change in QOL during the first year, but T-stage significantly affected the change in global health status, tumor site affected the changes in swallowing, sensory problems, sticky saliva, and complications affected the changes in pain, swallowing, and mouth opening. CONCLUSIONS QOL of oral cancer patients treated with LDR-BT is high. However, tumor stage, tumor site, and complications affected the changes in a few functions and symptoms during the first year.


Japanese Journal of Clinical Oncology | 2011

A Consensus-based Guideline Defining Clinical Target Volume for Primary Disease in External Beam Radiotherapy for Intact Uterine Cervical Cancer

Takafumi Toita; Tatsuya Ohno; Yuko Kaneyasu; Tomoyasu Kato; Takashi Uno; Kazuo Hatano; Yoshiki Norihisa; Takahiro Kasamatsu; Takeshi Kodaira; Ryo-ichi Yoshimura; Satoshi Ishikura; Masahiro Hiraoka

OBJECTIVE To develop a consensus-based guideline to define clinical target volume for primary disease (clinical target volume primary) in external beam radiotherapy for intact uterine cervical cancer. METHODS The working subgroup of the JCOG Radiation Therapy Study Group began developing a guideline for primary clinical target volume in November 2009. The group consisted of 10 radiation oncologists and 2 gynecologic oncologists. The process started with comparing the contouring on computed tomographic images of actual cervical cancer cases among the members. This was followed by a comprehensive literature review that included primary research articles and textbooks as well as information on surgical procedures. Extensive discussion occurred in face-to-face meetings (three occasions) and frequent e-mail communications until a consensus was reached. RESULTS The working subgroup reached a consensus on the definition for the clinical target volume primary. The clinical target volume primary consists of the gross tumor volume, uterine cervix, uterine corpus, parametrium, vagina and ovaries. Definitions for these component structures were determined. Anatomical boundaries in all directions were defined for the parametrium. Examples delineating these boundaries were prepared for the posterior border of the parametrium for various clinical situations (i.e. central tumor bulk, degree of parametrial involvement). CONCLUSIONS A consensus-based guideline defining the clinical target volume primary was developed for external beam radiotherapy for intact uterine cervical cancer. This guideline will serve as a template for radiotherapy protocols in future clinical trials. It may also be used in actual clinical practice in the setting of highly precise external beam radiotherapy, including intensity-modulated radiotherapy.


Strahlentherapie Und Onkologie | 2007

Curative Brachytherapy for Recurrent/Residual Tongue Cancer

Fumio Ayukawa; Hitoshi Shibuya; Ryo-ichi Yoshimura; Hiroshi Watanabe; Masahiko Miura

Purpose:The efficacy of curative low-dose-rate (LDR) brachytherapy for recurrent and/or residual cancer following radical operation or irradiation and posttreatment quality of life (QoL) were assessed.Patients and Methods:Between January 1979 and April 2004, 88 patients who had received curative LDR brachytherapy (28 with postoperative close or positive margins, six with postoperative recurrence, six with recurrence after external-beam irradiation, and 48 with recurrent/residual cancer after curative brachytherapy) were analyzed retrospectively. Late complications were assessed based on the RTOG/EORTC late radiation morbidity score scheme.Results:The 5-year relapse-free and cause-specific survival rates were 92% and 96%, respectively, in the close/positive margin group and 52% and 56%, respectively, in the postbrachytherapy recurrence or residual cancer group. The incidence of late side effects was 8% (2/26) in the close or positive margin group and 22% (4/18) in the postbrachytherapy group. The only grade 4 late complication (bone exposure) was observed in one patient in the postbrachytherapy group.Conclusion:LDR brachytherapy as reirradiation for recurrent/residual tongue cancer was effective, and there was no increase in complications.Ziel:Die Wirksamkeit einer kurativen Brachytherapie mit niedriger Dosisleistung (LDR) bei Rezidiv und/oder Resttumor nach radikaler Operation oder Bestrahlung wurde bezüglich der Lebensqualität nach Behandlung untersucht.Patienten und Methodik:88 Patienten, die zwischen Januar 1979 und April 2004 eine LDR-Brachytherapie erhalten hatten, wurden retrospektiv analysiert (28 mit knappen oder positiven Schnitträndern, sechs mit postoperativem Rezidiv, sechs mit Rezidiv nach Teletherapie sowie 48 mit Rezidiv bzw. Resttumor nach Brachytherapie). Späte Komplikationen wurden auf der Grundlage des „late radiation morbidity score scheme“ der RTOG/EORTC klassifiziert.Ergebnisse:Die rezidivfreie und die tumorspezifische 5-Jahres-Überlebensrate betrugen in der Gruppe mit knappen oder positiven Schnitträndern 92% und 96% sowie in der Gruppe mit Rezidiv oder Resttumor nach Brachytherapie 52% und 56%. Die Rate später Nebenwirkungen lag in der Gruppe mit Heilung/positivem Resultat bei 8% (2/26) und in der Gruppe nach Brachytherapie bei 22% (4/18). Die einzige Spätfolge des Grades 4 (Knochenfreilegung) war bei einem Patienten in der Gruppe nach Brachytherapie zu verzeichnen.Schlussfolgerung:Die LDR-Brachytherapie als erneute Bestrahlung erwies sich bei Rezidiv oder Resttumor eines Zungenkarzinoms als wirksam. Es kam zu keinem Anstieg der Komplikationen.


International Journal of Radiation Oncology Biology Physics | 2010

Outcomes in Patients With Early-Stage Hypopharyngeal Cancer Treated With Radiotherapy

Ryo-ichi Yoshimura; Yoshikazu Kagami; Yoshinori Ito; Masao Asai; Hiroshi Mayahara; Minako Sumi; Jun Itami

PURPOSE To analyze the outcome in patients with early-stage hypopharyngeal cancer (HPC) who were treated with radiotherapy (RT). METHODS AND MATERIALS Between February 1988 and February 2007, 77 patients with Stage I or Stage II HPC underwent definitive RT in the Division of Radiation Oncology at the National Cancer Center Hospital. Eleven of the patients received local irradiation, and the other 66 patients received elective bilateral neck irradiation and booster irradiation to the primary lesion. The median follow-up period for all the patients was 33 months from the start of RT, ranging from 3 to 229 months. RESULTS The rates of overall survival, HPC-specific survival, HPC recurrence-free survival, and local control with laryngeal voice preservation for the 77 patients at 5 years were 47%, 74%, 57%, and 70%, respectively. The survival rates were not affected by the patient characteristics or treatment factors, but the RT field was significantly correlated with local control in a multivariate analysis. Seven of the patients had Grade 3 or greater complications, but these complications occurred after salvage surgery in 6 of the patients. Of the 77 patients, 83% had synchronous or metachronous malignancies, but these malignancies did not influence the survival of the patients if the malignancies were detected at an early stage. CONCLUSION RT is an appropriate treatment method for early-stage HPC. However, because synchronous or metachronous malignancies occur at a relatively high frequency, careful follow-up and the early detection of such malignancies are critical.


Radiotherapy and Oncology | 2008

Prediction of lymphatic metastasis based on gene expression profile analysis after brachytherapy for early-stage oral tongue carcinoma

Hiroshi Watanabe; Kaoru Mogushi; Masahiko Miura; Ryo-ichi Yoshimura; Tohru Kurabayashi; Hitoshi Shibuya; Hiroshi Tanaka; Shuhei Noda; Mayumi Iwakawa; Takashi Imai

BACKGROUND AND PURPOSE The management of lymphatic metastasis of early-stage oral tongue carcinoma patients is crucial for its prognosis. The purpose of this study was to evaluate the predictive ability of lymphatic metastasis after brachytherapy (BRT) for early-stage tongue carcinoma based on gene expression profiling. PATIENTS AND METHODS Pre-therapeutic biopsies from 39 patients with T1 or T2 tongue cancer were analyzed for gene expression signatures using Codelink Uniset Human 20K Bioarray. All patients were treated with low dose-rate BRT for their primary lesions and underwent strict follow-up under a wait-and-see policy for cervical lymphatic metastasis. Candidate genes were selected for predicting lymph-node status in the reference group by the permutation test. Predictive accuracy was further evaluated by the prediction strength (PS) scoring system using an independent validation group. RESULTS We selected a set of 19 genes whose expression differed significantly between classes with or without lymphatic metastasis in the reference group. The lymph-node status in the validation group was predicted by the PS scoring system with an accuracy of 76%. CONCLUSIONS Gene expression profiling using 19 genes in primary tumor tissues may allow prediction of lymphatic metastasis after BRT for early-stage oral tongue carcinoma.


Brachytherapy | 2010

High–dose rate brachytherapy alone in postoperative soft tissue sarcomas with close or positive margins

Jun Itami; Minako Sumi; Yasuo Beppu; Hirokazu Chuman; Akira Kawai; Naoya Murakami; Madoka Morota; Hiroshi Mayahara; Ryo-ichi Yoshimura; Yoshinori Ito; Yoshikazu Kagami

PURPOSE In the management of soft tissue sarcomas, perioperative radiation therapy has been used to reduce the risk of local recurrence after resection. However, a significance of postoperative high-dose rate brachytherapy (HDRBT) remains to be studied. Retrospective analysis was performed to elucidate the role of postoperative HDRBT. METHODS AND MATERIALS Twenty-five patients with 26 soft tissue sarcoma lesions underwent postoperative HDRBT using (192)Ir remote afterloader without external beam radiation therapy. Ninety-two percent of the lesions were Grade 2 or 3 malignancies, and 50% were resected with positive surgical margins. The remaining 50% had very close margins. Fourteen lesions were treated for local recurrences after previous resections. Applicators of HDRBT were placed during the operation to include only the tumor bed excluding surgical scars. Applied dose was mainly 36Gy/6 fractions/3 d b.i.d. RESULTS Five-year local recurrence-free survival was 78.2% in all the 26 lesions. Recurrences were not seen within the treated volume of HDRBT. Two groups were defined according to the marginal status and number of previous operations. Group 1 was the lesions with a positive margin and foregoing resections. The remaining lesions were classified as Group 2. Five-year local recurrence-free survival was 43.8% and 93.3% in Group 1 and Group 2, respectively with a statistically significant difference (p=0.004). CONCLUSIONS Postoperative HDRBT was effective in controlling local lesions; but in Group 1 lesions, addition of a wide field external beam radiation therapy seems to be necessary to improve the local control rate.

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Hitoshi Shibuya

Tokyo Medical and Dental University

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Masahiko Miura

Tokyo Medical and Dental University

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Kazuma Toda

Tokyo Medical and Dental University

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Keiji Hayashi

Tokyo Medical and Dental University

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K. Nakagawa

Tokyo Medical and Dental University

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Minako Sumi

Japanese Foundation for Cancer Research

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