R Tsuchiya

Osaka Medical Center for Cancer and Cardiovascular Diseases, Ōsaka, Ōsaka, Japan

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Publications (381)754.28 Total impact

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    ABSTRACT: The objective of this study was to compare the sensitivity of detection of lung nodules on low-dose screening CT images between radiologists and technologists. 11 radiologists and 10 technologists read the low-dose screening CT images of 78 subjects. On images with a slice thickness of 5 mm, there were 60 lung nodules that were ≥5 mm in diameter: 26 nodules with pure ground-glass opacity (GGO), 7 nodules with mixed ground-glass opacity (GGO with a solid component) and 27 solid nodules. On images with a slice thickness of 2 mm, 69 lung nodules were ≥5 mm in diameter: 35 pure GGOs, 7 mixed GGOs and 27 solid nodules. The 21 observers read screening CT images of 5-mm slice thickness at first; then, 6 months later, they read screening CT images of 2-mm slice thickness from the 78 subjects. The differences in the mean sensitivities of detection of the pure GGOs, mixed GGOs and solid nodules between radiologists and technologists were not statistically significant, except for the case of solid nodules; the p-values of the differences for pure GGOs, mixed GGOs and solid nodules on the CT images with 5-mm slice thickness were 0.095, 0.461 and 0.005, respectively, and the corresponding p-values on CT images of 2-mm slice thickness were 0.971, 0.722 and 0.0037, respectively. Well-trained technologists may contribute to the detection of pure and mixed GGOs ≥5 mm in diameter on low-dose screening CT images.
    The British journal of radiology 09/2012; 85(1017):e603-8. · 2.11 Impact Factor
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    ABSTRACT: To publicize clinical results of Japanese lung cancer patients registered in 2002. Study design. In 2002, The Japanese Joint Committee for Lung Cancer Registration conducted a prospective observational study for lung cancer patients registered at starting treatments with follow-ups in 2004 and 2009. At first, 18,552 cases were registered from 358 institutes, while we analyzed 14,695 samples whose living periods could be identified. There were two times males as many as females with a mean age of 67.1 years. The most frequent histology was adenocarcinoma in 56.7%, following squamous cell carcinoma in 25.7% and small cell carcinoma in 9.2%. Clinical stage was IA in 29.3%, IB in 15.3%, IIA in 1.4%, IIB in 6.2%, IIIA in 11.8%, IIIB in 14.6% and IV in 21.0%. Surgery was performed in 8454 cases (57.5%). Five-year survival rate was 44.3% for all patients, 14.7% for cases of small cell carcinoma, 46.8% for non-small cell carcinoma, 59.6% for surgery cases, 8.5% for no surgery cases, 37.7% for males and 59.0% for females. The rates in clinical stage settings in cases of small cell carcinoma and non small cell carcinoma, was 52.7% and 79.4% for IA, 39.3% and 56.7% for IB, 31.7% and 49.0% for IIA, 29.9% and 42.3% for IIB, 17.2% and 30.9% for IIIA, 12.4% and 16.7% for IIIB and 3.8% and 5.8% for IV, respectively. An analysis of Japanese lung cancer patients registered in 2002 revealed that the most frequent histology type was adenocarcinoma following squamous cell carcinoma and small cell carcinoma. Prognosis in 5 years was superior in cases of female, non small cell lung cancer and surgery to those of male, small cell lung cancer and no surgery, respectively. Further investigation is needed with respect to dependences of those survival differences.
    Nihon Kokyūki Gakkai zasshi = the journal of the Japanese Respiratory Society. 04/2010; 48(4):333-44.
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    ABSTRACT: To evaluate a custom-developed software for analyzing malignant degrees of small peripheral adenocarcinomas on volumetric CT data compared to pathological prognostic factors. Forty-six adenocarcinomas with a diameter of 2cm or less from 46 patients were included. The custom-developed software can calculate the volumetric rates of solid parts to whole nodules even though solid parts show a punctate distribution, and automatically classify nodules into the following six types according to the volumetric rates of solid parts: type 1, pure ground-glass opacity (GGO); type 2, semiconsolidation; type 3, small solid part with a GGO halo; type 4, mixed type with an area that consisted of GGO and solid parts which have air-bronchogram or show a punctate distribution; type 5, large solid part with a GGO halo; and type 6, pure solid type. The boundary between solid portion and GGO on CT was decided using two threshold selection methods for segmenting gray-scale images. A radiologist also examined two-dimensional rates of solid parts to total opacity (2D%solid) which was already confirmed with previous reports. There were good agreements between the classification determined by the software and radiologists (weighted kappa=0.778-0.804). Multivariate logistic regression analyses showed that both 2D%solid and computer-automated classification were significantly useful in estimating lymphatic invasion (p=0.0007, 0.0027), vascular invasion (p=0.003, 0.012), and pleural invasion (p=0.021, 0.025). Using our custom-developed software, it is feasible to predict the pathological prognostic factors of small peripheral adenocarcinomas.
    Lung cancer (Amsterdam, Netherlands) 04/2010; 70(3):286-94. · 3.14 Impact Factor
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    ABSTRACT: In 1986, Japanese Association for Thoracic Surgery started a nationwide survey of the number of primary lung cancer undergoing resection and this survey was continued annually. Thereafter, investigations of lung cancer surgical results have been conducted three times. The postoperative overall 5-year survival rate was 47.8% in resected cases in 1989, 52.3% in 1994, and 62.0% in 1999, showing improvement over the decade (p < 0.01). To clarify the factors influencing survival improvements retrospectively. The subjects of the investigation are the patients who underwent resection for primary lung cancers in 1989, 1994, and 1999. Postoperatively, after 5 years, surveys of surgical results were sent to institutes where lung cancer resection had been performed. The subjects undergoing resection who provided 10 items (age, sex, pathologic T factor, pathologic N factor, pathologic M factor, date of resection, histology, curability, prognosis, and survival time) numbered 3004 in 1989, 6895 in 1994, and 12,235 in 1999. They were classified according to the Union International Contre le Cancer 1997 revised tumor, node, and metastasis classification. Differences in age, gender, histology, pathologic stage, curability, and operative death rates were analyzed for each survey year. According to the changes in proportions, the cases over 70 years of age, women, and pathologic stage I increased significantly (p < 0.001), whereas in cases with small cell lung cancer, incomplete resection and operative death decreased significantly over time (p < 0.001). The postoperative 5-year survival rate in Japan improved between 1989 and 1999. The main cause of this improvement was the increase in early stage lung cancer, especially cases with tumors 2 cm or less in size.
    Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 11/2009; 4(11):1364-9. · 4.55 Impact Factor
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    ABSTRACT: This retrospective study was designed to identify the predictors of long-term survival and the risk factors for complications after surgery in patients aged 80 years or older with clinical (c)-stage I non-small cell lung cancer. The Japanese Joint Committee of Lung Cancer Registry collated the clinicopathological profiles and outcomes of 13,344 patients who underwent pulmonary resection for primary lung cancer in 1999. The data of 367 patients aged 80 years or older with c-stage I non-small cell lung cancer were analyzed for prognostic factors and risk factors for postoperative complications. The median age was 82 years (range, 80-90 years). Of the total patient number, 102 (27.8%) had some form of comorbidity diagnosed preoperatively. Thirty-one (8.4%) patients presented with postoperative complications, and the operative mortality was 1.4%. The 5-year survival rates were 55.7% for c-stage I patients, 62.0% for c-stage IA, and 47.2% for c-stage IB. Advanced pathologic stage and comorbidity were significant independent predictors of shortened survival (p < 0.0001 and p = 0.032, respectively). Comorbidity and mediastinal lymph node dissection were identified as factors that increased the risk of postoperative complications (p < 0.0001 and p = 0.036, respectively). Survival rates were independent of the extent of pulmonary resection (lobectomy or limited resection). Octogenarian patients with c-stage I lung cancer in this study had a satisfactory long-term outcome and low-mortality rate. Comorbidity is a factor associated with both prognosis and operative risks. A selection of the patients who would be curable without mediastinal lymph node dissection after an accurate preoperative staging is beneficial to decrease the postoperative complications because this procedure is a risk factor.
    Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 07/2009; 4(10):1247-53. · 4.55 Impact Factor
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    ABSTRACT: No analyses have been reported on the impact of visceral pleura invasion (VPI) on staging, in relation with the International Association for the Study of Lung Cancer proposals for the 7th edition of the tumor, node, metastasis (TNM) classification of the International Union Against Cancer staging system. The purpose of this study was to evaluate the impact of VPI on survival and propose a method of incorporating VPI status into the TNM classification. We reviewed the data on 9758 non-small cell lung cancer patients, who underwent anatomic surgical resection in 1999, accumulated by the Japanese Joint Committee for Lung Cancer Registration, to gain insight into their clinicopathologic characteristics and outcomes. VPI was defined as tumor extension beyond the elastic layer of the visceral pleura. Patients were divided into nine groups according to VPI status and tumor diameter, in accordance with the International Association for the Study of Lung Cancer proposals. On the basis of survival, the nine groups were divided into the following five levels: tumors < or =2 cm without VPI; tumors < or =2 cm with VPI and tumors 2.1 to 3 cm without VPI; tumors 2.1 to 3 cm with VPI and tumors 3.1 to 5 cm without VPI; tumors 3.1 to 5 cm with VPI and tumors 5.1 to 7 cm without VPI; and tumors 5.1 to 7 cm with VPI and tumors >7 cm without VPI or T3 tumors. The T status of tumors, 7 cm or less, with VPI should be upgraded to the next T level in the future edition of the TNM classification of International Union Against Cancer staging system.
    Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 06/2009; 4(8):959-63. · 4.55 Impact Factor
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    ABSTRACT: Twenty-two resected goblet cell type adenocarcinomas of the lung were examined clinicopathologically and immunohistochemically. The stage and survival curve of goblet cell type adenocarcinomas were compared with those of 44 cases of pure or mixed Clara cell and bronchial surface epithelial cell (Clara and BSE) type adenocarcinomas. Each case of goblet cell type was matched with two cases of Clara and BSE type as to sex, age and date of surgery. In goblet cell type adenocarcinomas, lymph node metastasis was less frequently and intrapulmonary metastasis was more frequently detected than in other types of adenocarcinomas (p < 0.001 and p < 0.05, respectively). Goblet cell type adenocarcinomas showed better prognoses than Clara and BSE type adenocarcinomas. However, the estimated survival curves of those two groups become similar after adjustment of the TNM condition using Cox's proportional-hazard general linear model. This result indicated that the longer survival of goblet cell type adenocarcinoma was due to the characteristic distribution of TNM conditions, that is, unique local growth and low incidence of lymph node metastasis. When goblet cell type adenocarcinoma was macroscopically classified into two types, i.e. solitary peripheral nodule type (nodular type) and multifocal nodular type or consolidation of all or part of a lobe (diffuse type), the nodular type had better prognosis than the diffuse type (p < 0.05). Immunohistochemically, 83%, 11%, and 0% of goblet cell type adenocarcinomas were positive for NCC-CO-450, carcinoembryonic antigen (CEA), and surfactant apoprotein, respectively. Most Clara and BSE type adenocarcinomas were negative for NCC-CO-450, but positive for CEA and surfactant apoprotein. NCC-CO-450 was considered to be a good immunohistochemical marker of goblet cell type adenocarcinoma of the lung. These results indicated that goblet cell type tumors are different from most adenocarcinomas of other types both clinicopathologically and immunohistochemically. Acta Pathol Jpn 41: 737-743, 1991.
    Pathology International 12/2008; 41(10):737 - 743. · 1.72 Impact Factor
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    ABSTRACT: Recently, Yamakawa et al. following Masaoka's clinical staging of thymic epithelial tumors, proposed a TNM classification and staging system for thymic epithelial tumors including thymoma and thymic carcinoma. The present authors consider that division of thymomas into circumscribed types (either encapsulated or non-encapsulated but confined to within the thymus) and those invasive to adjacent organs or structures is sufficiently practical, and that a staging system is applicable to thymic carcinoma, carcinoid tumors and germ cell tumors of the anterior mediastinum, which are more malignant than thymoma. Therefore, the utility of the Yamakawa/MasaokaTNM and staging system was evaluated and a modification proposed based on experience with 16 thymic carcinomas. Although there were no cases at stage II, the survival curves obtained using the proposed modified system were more clearly separated between stages I and III or IV and between stages III and IV than the curves obtained using the Yamakawa/Masaoka system. However, the differences were not significant because of the small number of cases included. A statistically significant difference was noted between the survival curves for patients who underwent complete and incomplete surgical resection of the tumor. The utility of this proposed TNM and staging system must be evaluated by other investigators, since no cases of small cell carcinoma, lymphoepithelioma-like carcinoma, sarcomatoid carcinoma and clear cell carcinoma were included in this series, all of which are considered to have high-grade histology. An evaluation of carcinoid tumor and germ cell tumor of the anterior mediastinum must also be made.
    Pathology International 12/2008; 44(7):505 - 512. · 1.72 Impact Factor
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    ABSTRACT: We conducted a study to determine optimal scan conditions for automatic exposure control (AEC) in computed tomography (CT) of low-dose chest screening in order to provide consistent image quality without increasing the collective dose. Using a chest CT phantom, we set CT-AEC scan conditions with a dose-reduction wedge (DR-Wedge) to the same radiation dose as those for low-tube current, fixed-scan conditions. Image quality was evaluated with the use of the standard deviation of the CT number, contrast-noise ratios (CNR), and receiver-operating characteristic (ROC) analysis. At the same radiation dose, in the scan conditions using CT-AEC with the DR-Wedge, the SD of the CT number of each slice position was stable. The CNR values were higher at the lung apex and lung base under CT-AEC with the DR-Wedge than under standard scan conditions (p < 0.0002). In addition, ROC analysis of blind evaluation by four radiologists and three technologists showed that the image quality was improved for the lung apex (p < 0.009), tracheal bifurcation (p < 0.038), and lung base (p < 0.022) in the scan conditions using CT-AEC with the DR-Wedge. We achieved improvement of image quality without increasing the collective dose by using CT-AEC with the DR-Wedge under low-dose scan conditions.
    Radiological Physics and Technology 07/2008; 1(2):244-50.
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    ABSTRACT: The validation of tumor, node, metastasis staging system in terms of prognosis is an indispensable part of establishing a better staging system in lung cancer. In 2005, 387 Japanese institutions submitted information regarding the prognosis and clinicopathologic profiles of patients who underwent pulmonary resections for primary lung neoplasms in 1999 to the Japanese Joint Committee of Lung Cancer Registry. The data of 13,010 patients with only lung carcinoma histology (97.6%) were analyzed in terms of prognosis and clinicopathologic characteristics. The 5-year survival rate of the entire group was 61.4%. For the small cell histology (n = 390), the 5-year survival rates according to clinical (c) and pathologic (p) stages were as follows: 58.8% (n = 161) and 58.3% (n = 127) for IA, 58.0% (n = 77) and 60.2% (n = 79) for IB, 47.1% (n = 17) and 40.6% (n = 29) for IIA, 25.3% (n = 38) and 41.1% (n = 29) for IIB, 29.0% (n = 61) and 28.3% (n = 60) for IIIA, 36.3% (n = 19) and 34.6% (n = 40) for IIIB, and 27.8% (n = 12) and 30.8% for IV (n = 13). For the non-small cell histology (n = 12,620), the 5-year survival rates according to c-stage and p-stage were as follows: 77.3% (n = 5642) and 83.9% (n = 4772) for IA, 59.8% (n = 3081) and 66.3% (n = 2629) for IB, 54.1% (n = 205) and 61.0% (n = 361) for IIA, 43.9% (n = 1227) and 47.4% (n = 1330) for IIB, 38.3% (n = 1628) and 32.8% (n = 1862) for IIIA, 32.6% (n = 526) and 29.6% (n = 1108) for IIIB, and 26.5% (n = 198) and 23.1% (n = 375) for IV. Adenocarcinoma, female gender, and age less than 50 years were significant favorable prognostic factors. This large registry study provides benchmark prognostic statistics for lung cancer. The prognostic difference between stages IB and IIA was small despite different stages. Otherwise, the present tumor, node, metastasis staging system well characterizes the stage-specific prognoses.
    Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 02/2008; 3(1):46-52. · 4.55 Impact Factor
  • Haigan 01/2008; 48(3):176-184.
  • Haigan 01/2008; 48(6):754-758.
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    ABSTRACT: We have measured the polarizations of J/psi and psi(2S) mesons as functions of their transverse momentum p(T) when they are produced promptly in the rapidity range |y| < 0.6 with p(T) > or =5 GeV/c. The analysis is performed using a data sample with an integrated luminosity of about 800 pb(-1) collected by the CDF II detector. For both vector mesons, we find that the polarizations become increasingly longitudinal as p(T) increases from 5 to 30 GeV/c. These results are compared to the predictions of nonrelativistic quantum chromodynamics and other contemporary models. The effective polarizations of J/psi and psi(2S) mesons from B-hadron decays are also reported.
    Physical Review Letters 09/2007; 99(13):132001. · 7.73 Impact Factor
  • Ryosuke Tsuchiya
    Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 08/2007; 2(7 Suppl 3):S113-4. · 4.55 Impact Factor
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    ABSTRACT: Accurate staging of lymph node involvement is a critical aspect of the initial management of nonmetastatic non-small cell lung cancer (NSCLC). We sought to determine whether the current N descriptors should be maintained or revised for the next edition of the international lung cancer staging system. A retrospective international lung cancer database was developed and analyzed. Anatomical location of lymph node involvement was defined by the Naruke (for Japanese data) and American Thoracic Society (for non-Japanese data) nodal maps. Survival was calculated by the Kaplan-Meier method, and prognostic groups were assessed by Cox regression analysis. Current N0 to N3 descriptors defined distinct prognostic groups for both clinical and pathologic staging. Exploratory analyses indicated that lymph node stations could be grouped together into six "zones": peripheral or hilar for N1, and upper or lower mediastinal, aortopulmonary, and subcarinal for N2 nodes. Among patients undergoing resection without induction therapy, there were three distinct prognostic groups: single-zone N1, multiple-zone N1 or single N2, and multiple-zone N2 disease. Nevertheless, there were insufficient data to determine whether the N descriptors should be subdivided (e.g., N1a, N1b, N2a, N2b). Current N descriptors should be maintained in the NSCLC staging system. Prospective studies are needed to validate amalgamating lymph node stations into zones and subdividing N descriptors.
    Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 08/2007; 2(7):603-12. · 4.55 Impact Factor
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    ABSTRACT: We describe a search for anomalous production of events with two leptons (e or mu) of the same electric charge in pp[over ] collisions at a center-of-mass energy of 1.96 TeV. Many extensions to the standard model predict the production of two leptons of the same electric charge. This search has a significant increase in sensitivity compared to earlier searches. Using a data sample corresponding to 1 fb(-1) of integrated luminosity recorded by the CDF II detector, we observe no significant excess in an inclusive selection (expect 33.2+/-4.7 events, observe 44) or in a supersymmetry-optimized selection (expect 7.8+/-1.1 events, observe 13.).
    Physical Review Letters 07/2007; 98(22):221803. · 7.73 Impact Factor
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    ABSTRACT: The objective of this retrospective study was to identify prognostic factors in completely resected clinical (c-) stage I non-small cell lung cancer cases. In 2001, the Japanese Joint Committee of Lung Cancer Registry collected data on the outcome and clinicopathological profiles of 7408 patients who had undergone resection for primary lung cancer in 1994. They included 3315 c-stage I patients who underwent complete resection, and in this study attempted to identify prognostic factors in the c-stage IA and c-stage IB cases. The overall 5-year survival rate was 66.5%: 74.7% in the 2085 c-stage IA cases and 52.5% in the 1230 c-stage IB cases. The survival curve of the c-stage IA cases was higher than that of the c-stage IB cases. Multivariate analysis of the c-stage IA cases revealed six factors that predicted a significantly better outcome: age, gender, pathological (p-) T status, p-N status, nodal dissection, and tumor diameter (< or =2 cm), and the same analysis of the c-stage IB cases revealed six factors: age, gender, p-T status, p-N status, operative procedure, and tumor diameter (<5 cm). The c-stage IA patients whose tumor diameter was 2 cm or less had a higher survival rate than the patients whose tumor diameter was more than 2 cm, and the c-stage IB patients whose tumor diameter was less than 5 cm had a higher survival rate than the patients whose tumor diameter was 5 cm or more. Tumor size is an independent prognostic factor for postoperative survival in c-stage I patients.
    Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 06/2007; 2(5):408-13. · 4.55 Impact Factor
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    ABSTRACT: We measure the ratio of cross section times branching fraction, Rp=sigma chi c2 B(chi c2-->J/psi gamma)/sigma chi c1 B(chi c1-->J/psi gamma), in 1.1 fb(-1) of pp collisions at square root s=1.96 TeV. This measurement covers the kinematic range pT(J/psi)>4.0 GeV/c, |eta(J/psi)<1.0, and pT(gamma)>1.0 GeV/c. For events due to prompt processes, we find Rp=0.395+/-0.016(stat)+/-0.015(syst). This result represents a significant improvement in precision over previous measurements of prompt chi c1,2 hadro production.
    Physical Review Letters 06/2007; 98(23):232001. · 7.73 Impact Factor
  • Physical review D: Particles and fields 05/2007; 75(11):119901.
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    ABSTRACT: We present a measurement of the inclusive production cross section for Z bosons decaying to tau leptons in pp̅ collisions at √s=1.96 TeV. We use a channel with one hadronically-decaying and one electronically-decaying tau. This measurement is based on 350 pb-1 of CDF Run II data. Using a sample of 504 opposite sign eτ events with a total expected background of 190 events, we obtain σ(pp̅ →4Z)·B(Z→ττ)=264±23(stat)±14(syst)±15(lumi) pb, in agreement with the next-to-next-to-leading order QCD prediction. This is the first CDF cross section measurement using hadronically-decaying taus in Run II.
    Phys. Rev. D. 05/2007; 75(9).

Publication Stats

4k Citations
754.28 Total Impact Points

Institutions

  • 2009
    • Osaka Medical Center for Cancer and Cardiovascular Diseases
      Ōsaka, Ōsaka, Japan
  • 2007–2009
    • Niigata Cancer Center Hospital
      Niahi-niigata, Niigata, Japan
    • University of Helsinki
      • Department of Physics
      Helsinki, Province of Southern Finland, Finland
  • 1988–2009
    • National Cancer Center, Japan
      • • Center for Cancer Control and Information Services
      • • Department of Diagnostic Radiology
      • • Endoscopy Division
      Edo, Tōkyō, Japan
  • 2008
    • Fukuoka University
      • Department of Internal Medicine
      Hukuoka, Fukuoka, Japan
  • 1984–2008
    • National Hospital Organization Kyushu Cancer Center
      Hukuoka, Fukuoka, Japan
  • 1977–2007
    • University of Illinois, Urbana-Champaign
      Urbana, Illinois, United States
  • 1970–2007
    • Waseda University
      Edo, Tōkyō, Japan
  • 2004–2006
    • University of Florida
      Gainesville, Florida, United States
    • Academia Sinica
      • Institute of Physics
      Taipei, Taipei, Taiwan
    • Osaka City General Hospital
      Ōsaka, Ōsaka, Japan
  • 2005
    • Kyorin University
      • Department of Surgery
      Edo, Tōkyō, Japan
  • 2003
    • Chiba-East National Hospital
      Tiba, Chiba, Japan
  • 2000
    • Tohoku University
      Japan
  • 1972–1977
    • Nagasaki University
      Nagasaki, Nagasaki, Japan
  • 1971–1975
    • Nagasaki University Hospital
      Nagasaki, Nagasaki, Japan