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Dive into the research topics where Kazuhiro Yasufuku is active.

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Featured researches published by Kazuhiro Yasufuku.


The New England Journal of Medicine | 2011

Normothermic Ex Vivo Lung Perfusion in Clinical Lung Transplantation

Marcelo Cypel; Jonathan C. Yeung; Mingyao Liu; Masaki Anraku; Fengshi Chen; W. Karolak; Masaaki Sato; Jane Laratta; S. Azad; Mindy Madonik; Chung-Wai Chow; C. Chaparro; Michael Hutcheon; Lianne G. Singer; Arthur S. Slutsky; Kazuhiro Yasufuku; Marc de Perrot; A. Pierre; Thomas K. Waddell; Shaf Keshavjee

BACKGROUND More than 80% of donor lungs are potentially injured and therefore not considered suitable for transplantation. With the use of normothermic ex vivo lung perfusion (EVLP), the retrieved donor lung can be perfused in an ex vivo circuit, providing an opportunity to reassess its function before transplantation. In this study, we examined the feasibility of transplanting high-risk donor lungs that have undergone EVLP. METHODS In this prospective, nonrandomized clinical trial, we subjected lungs considered to be high risk for transplantation to 4 hours of EVLP. High-risk donor lungs were defined by specific criteria, including pulmonary edema and a ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen (PO(2):FIO(2)) less than 300 mm Hg. Lungs with acceptable function were subsequently transplanted. Lungs that were transplanted without EVLP during the same period were used as controls. The primary end point was primary graft dysfunction 72 hours after transplantation. Secondary end points were 30-day mortality, bronchial complications, duration of mechanical ventilation, and length of stay in the intensive care unit and hospital. RESULTS During the study period, 136 lungs were transplanted. Lungs from 23 donors met the inclusion criteria for EVLP; in 20 of these lungs, physiological function remained stable during EVLP and the median PO(2):FIO(2) ratio increased from 335 mm Hg in the donor lung to 414 and 443 mm Hg at 1 hour and 4 hours of perfusion, respectively (P<0.001). These 20 lungs were transplanted; the other 116 lungs constituted the control group. The incidence of primary graft dysfunction 72 hours after transplantation was 15% in the EVLP group and 30% in the control group (P=0.11). No significant differences were observed for any secondary end points, and no severe adverse events were directly attributable to EVLP. CONCLUSIONS Transplantation of high-risk donor lungs that were physiologically stable during 4 hours of ex vivo perfusion led to results similar to those obtained with conventionally selected lungs. (Funded by Vitrolife; ClinicalTrials.gov number, NCT01190059.).


The New England Journal of Medicine | 2013

Probability of Cancer in Pulmonary Nodules Detected on First Screening CT

Annette McWilliams; Martin C. Tammemagi; John R. Mayo; Heidi C. Roberts; Geoffrey Liu; Kam Soghrati; Kazuhiro Yasufuku; Simon Martel; Francis Laberge; Michel Gingras; Sukhinder Atkar-Khattra; Christine D. Berg; Kenneth G. Evans; Richard J. Finley; John Yee; John C. English; Paola Nasute; John R. Goffin; Serge Puksa; Lori Stewart; Scott Tsai; Michael R. Johnston; Daria Manos; Garth Nicholas; Glenwood D. Goss; Jean M. Seely; Kayvan Amjadi; Alain Tremblay; Paul Burrowes; Paul MacEachern

BACKGROUND Major issues in the implementation of screening for lung cancer by means of low-dose computed tomography (CT) are the definition of a positive result and the management of lung nodules detected on the scans. We conducted a population-based prospective study to determine factors predicting the probability that lung nodules detected on the first screening low-dose CT scans are malignant or will be found to be malignant on follow-up. METHODS We analyzed data from two cohorts of participants undergoing low-dose CT screening. The development data set included participants in the Pan-Canadian Early Detection of Lung Cancer Study (PanCan). The validation data set included participants involved in chemoprevention trials at the British Columbia Cancer Agency (BCCA), sponsored by the U.S. National Cancer Institute. The final outcomes of all nodules of any size that were detected on baseline low-dose CT scans were tracked. Parsimonious and fuller multivariable logistic-regression models were prepared to estimate the probability of lung cancer. RESULTS In the PanCan data set, 1871 persons had 7008 nodules, of which 102 were malignant, and in the BCCA data set, 1090 persons had 5021 nodules, of which 42 were malignant. Among persons with nodules, the rates of cancer in the two data sets were 5.5% and 3.7%, respectively. Predictors of cancer in the model included older age, female sex, family history of lung cancer, emphysema, larger nodule size, location of the nodule in the upper lobe, part-solid nodule type, lower nodule count, and spiculation. Our final parsimonious and full models showed excellent discrimination and calibration, with areas under the receiver-operating-characteristic curve of more than 0.90, even for nodules that were 10 mm or smaller in the validation set. CONCLUSIONS Predictive tools based on patient and nodule characteristics can be used to accurately estimate the probability that lung nodules detected on baseline screening low-dose CT scans are malignant. (Funded by the Terry Fox Research Institute and others; ClinicalTrials.gov number, NCT00751660.).


European Respiratory Journal | 2007

Endobronchial ultrasound: new insight for the diagnosis of sarcoidosis.

M. Wong; Kazuhiro Yasufuku; Takahiro Nakajima; Felix J.F. Herth; Yasuo Sekine; Kiyoshi Shibuya; Toshihiko Iizasa; Kenzo Hiroshima; W. K. Lam; Takehiko Fujisawa

A diagnosis of sarcoidosis should be substantiated by pathological means in order to thoroughly exclude other diseases. The role of real-time endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the diagnosis of sarcoidosis has not been reported. The purpose of the present study is to evaluate the diagnostic yield of EBUS-TBNA in demonstrating the pathological features of sarcoidosis. In total, 65 patients with suspected sarcoidosis, with enlarged hilar or mediastinal lymph nodes on computed tomography, were included in the study. Patients with a suspected or known malignancy or previously established diagnosis of sarcoidosis were excluded. Convex probe endobronchial ultrasonography integrated with a separate working channel was used for EBUS-TBNA. Surgical methods were performed in those in whom no granulomas were detected by EBUS-TBNA. Patients were followed up clinically. EBUS-TBNA was performed on a total of 77 lymph node stations in 65 patients. A final diagnosis of sarcoidosis was made for 61 (93.8%) of the patients. The remaining four patients were diagnosed as having Wegeners granulomatosis (n = 1) or indefinite (n = 3). In patients with a final diagnosis of sarcoidosis, EBUS-TBNA demonstrated noncaseating epithelioid cell granulomas in 56 (91.8%) of the patients. No complications were reported. Endobronchial ultrasound-guided transbronchial needle aspiration proved to be a safe procedure with a high yield for the diagnoses of sarcoidosis.


Journal of Clinical Oncology | 2008

Endobronchial Ultrasound With Transbronchial Needle Aspiration for Restaging the Mediastinum in Lung Cancer

Felix J.F. Herth; Jouke T. Annema; Ralf Eberhardt; Kazuhiro Yasufuku; Armin Ernst; Mark Krasnik; Robert C. Rintoul

PURPOSE To investigate the sensitivity and accuracy of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for restaging the mediastinum after induction chemotherapy in patients with non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS One hundred twenty-four consecutive patients with tissue-proven stage IIIA-N2 disease who were treated with induction chemotherapy and who had undergone mediastinal restaging by EBUS-TBNA were reviewed. On the basis of computed tomography, 58 patients were classified as having stable disease and 66 were judged to have had a partial response. All patients subsequently underwent thoracotomy with attempted curative resection and a lymph node dissection regardless of EBUS-TBNA findings. RESULTS Persistent nodal metastases were detected by using EBUS-TBNA in 89 patients (72%). Of the 35 patients in whom no metastases were assessed by EBUS-TBNA, 28 were found to have residual stage IIIA-N2 disease at thoracotomy. The majority (91%) of these false negative results were due to nodal sampling error rather than detection error. Overall sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of EBUS-TBNA for mediastinal restaging after induction chemotherapy were 76%, 100%, 100%, 20%, and 77%, respectively. CONCLUSION EBUS-TBNA is a sensitive, specific, accurate, and minimally invasive test for mediastinal restaging of patients with NSCLC. However, because of the low negative predictive value, tumor-negative findings should be confirmed by surgical staging before thoracotomy.


Journal of Immunology | 2002

Evidence for Immune Responses to a Self-Antigen in Lung Transplantation: Role of Type V Collagen-Specific T Cells in the Pathogenesis of Lung Allograft Rejection

M. Azizul Haque; Teruaki Mizobuchi; Kazuhiro Yasufuku; Takehiko Fujisawa; Randy R. Brutkiewicz; Yan Zheng; Kena Woods; Gerald N. Smith; Oscar W. Cummings; Kathleen M. Heidler; Janice S. Blum; David S. Wilkes

We have reported that lung allograft rejection involves an immune response to a native protein in the lung, type V collagen (col(V)), and that col(V)-induced oral tolerance prevented acute and chronic rejection. In support of these findings col(V) fragments were detected in allografts during rejection, but not in normal lungs. The purpose of the current study was to isolate and characterize col(V)-specific allograft-infiltrating T cells and to determine their contribution to the rejection response in vivo. Two col(V)-specific T cell lines, LT1 and LT3, were isolated from F344 (RT1lv1) rat lung allografts during rejection that occurred after transplantation into WKY (RT1l) recipients. Both cell lines, but not normal lung lymphocytes, proliferated in response to col(V). Neither LT1 nor LT3 proliferated in response to alloantigens. LT1 and LT3 were CD4+CD25− and produced IFN-γ in response to col(V). Compared with normal CD4+ T cells, both cell lines expressed a limited V-β TCR repertoire. Each cell strongly expressed V-β 9 and 16, but differed in expression of other V-βs. Adoptive transfer of each cell line did not induce pathology in lungs of normal WKY rats. In contrast, adoptive transfer of LT1, but not LT3, caused marked peribronchiolar and perivascular inflammation in isograft (WKY) lungs and abrogated col(V)-induced oral tolerance to allograft (F344) lungs. Collectively, these data show that lung allograft rejection involves both allo- and autoimmune responses, and graft destruction that occurs during the rejection response may expose allograft-infiltrating T cells to potentially antigenic epitopes in col(V).


The Journal of Thoracic and Cardiovascular Surgery | 2012

Experience with the first 50 ex vivo lung perfusions in clinical transplantation.

Marcelo Cypel; Jonathan C. Yeung; T.N. Machuca; M. Chen; Lianne G. Singer; Kazuhiro Yasufuku; Marc de Perrot; A. Pierre; Thomas K. Waddell; Shaf Keshavjee

OBJECTIVE Normothermic ex vivo lung perfusion is a novel method to evaluate and improve the function of injured donor lungs. We reviewed our experience with 50 consecutive transplants after ex vivo lung perfusion. METHODS A retrospective study using prospectively collected data was performed. High-risk brain death donor lungs (defined as Pao(2)/Fio(2) <300 mm Hg or lungs with radiographic or clinical findings of pulmonary edema) and lungs from cardiac death donors were subjected to 4 to 6 hours of ex vivo lung perfusion. Lungs that achieved stable airway and vascular pressures and Pao(2)/Fio(2) greater than 400 mm Hg during ex vivo lung perfusion were transplanted. The primary end point was the incidence of primary graft dysfunction grade 3 at 72 hours after transplantation. End points were compared with lung transplants not treated with ex vivo lung perfusion (controls). RESULTS A total of 317 lung transplants were performed during the study period (39 months). Fifty-eight ex vivo lung perfusion procedures were performed, resulting in 50 transplants (86% use). Of these, 22 were from cardiac death donors and 28 were from brain death donors. The mean donor Pao(2)/Fio(2) was 334 mm Hg in the ex vivo lung perfusion group and 452 mm Hg in the control group (P = .0001). The incidence of primary graft dysfunction grade 3 at 72 hours was 2% in the ex vivo lung perfusion group and 8.5% in the control group (P = .14). One patient (2%) in the ex vivo lung perfusion group and 7 patients (2.7%) in the control group required extracorporeal lung support for primary graft dysfunction (P = 1.00). The median time to extubation, intensive care unit stay, and hospital length of stay were 2, 4, and 20 days, respectively, in the ex vivo lung perfusion group and 2, 4, and 23 days, respectively, in the control group (P > .05). Thirty-day mortality (4% in the ex vivo lung perfusion group and 3.5% in the control group, P = 1.00) and 1-year survival (87% in the ex vivo lung perfusion group and 86% in the control group, P = 1.00) were similar in both groups. CONCLUSIONS Transplantation of high-risk donor lungs after 4 to 6 hours of ex vivo lung perfusion is safe, and outcomes are similar to those of conventional transplants. Ex vivo lung perfusion improved our center use of donor lungs, accounting for 20% of our current lung transplant activity.


Clinical Cancer Research | 2010

EML4-ALK Fusion Gene Assessment Using Metastatic Lymph Node Samples Obtained by Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration

Yuichi Sakairi; Takahiro Nakajima; Kazuhiro Yasufuku; Dai Ikebe; Hajime Kageyama; Manabu Soda; Kengo Takeuchi; Makiko Itami; Toshihiko Iizasa; Ichiro Yoshino; Hiroyuki Mano; Hideki Kimura

Purpose: Anaplastic lymphoma kinase (ALK) fusion genes represent novel oncogenes for non–small cell lung cancers (NSCLC). Several ALK inhibitors have been developed, and are now being evaluated in ALK-positive NSCLC. The feasibility of detecting ALK fusion genes in samples obtained by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) was determined. The clinicopathologic characteristics of ALK-positive lung cancer were also analyzed. Experimental Design: From April 2008 to July 2009, NSCLC cases with hilar/mediastinal lymph node metastases detected by EBUS-TBNA were enrolled. Positive expression of ALK fusion protein was determined using immunohistochemistry, and ALK gene rearrangements were further examined to verify the translocation between ALK and partner genes using fluorescent in situ hybridization and reverse transcription-PCR. Direct sequencing of PCR products was performed to identify ALK fusion variants. Results: One hundred and nine cases were eligible for the analysis using re-sliced samples. Screening of these specimens with immunohistochemistry revealed ALK positivity in seven cases (6.4%), all of which possessed echinoderm microtubule–associated protein-like 4–ALK fusion genes as detected by fluorescent in situ hybridization and reverse transcription-PCR. All ALK-positive cases had an adenocarcinoma histology and possessed no EGFR mutations. Compared with ALK-negative cases, ALK-positive cases were more likely to have smaller primary tumors (P < 0.05), to occur at a younger age (<60 years; P < 0.05), and to occur in never/light smokers (smoking index < 400; P < 0.01). Mucin production was frequently observed in ALK-positive adenocarcinomas (29.4%; P < 0.01). Conclusions: EBUS-TBNA is a practical and feasible method for obtaining tissue from mediastinal and hilar lymph nodes that can be subjected to multimodal analysis of ALK fusion genes in NSCLC. Clin Cancer Res; 16(20); 4938–45. ©2010 AACR.


Chest | 2010

The utility of sonographic features during endobronchial ultrasound-guided transbronchial needle aspiration for lymph node staging in patients with lung cancer: a standard endobronchial ultrasound image classification system.

Taiki Fujiwara; Kazuhiro Yasufuku; Takahiro Nakajima; Masako Chiyo; Shigetoshi Yoshida; Makoto Suzuki; Kiyoshi Shibuya; Kenzo Hiroshima; Yukio Nakatani; Ichiro Yoshino

BACKGROUND Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure with a high yield for lymph node staging of lung cancer. The aim of this study was to assess the utility of sonographic features of lymph nodes during EBUS-TBNA for the prediction of metastasis in patients with lung cancer and to establish a standard endobronchial ultrasound (EBUS) image classification system. METHODS Digital images of lymph nodes obtained during EBUS-TBNA in patients with lung cancer were categorized according to the following characteristics: (1) size (short axis) less or more than 1 cm, (2) shape (oval or round), (3) margin (indistinct or distinct), (4) echogenicity (homogeneous or heterogeneous), (5) presence or absence of central hilar structure, and (6) presence or absence of coagulation necrosis sign. The sonographic findings were compared with the final pathologic results. RESULTS A total of 1,061 lymph nodes were retrospectively evaluated in 487 patients. The accuracy of predicting metastatic property for each category was as high as 63.8% to 86.0%. A multivariate analysis revealed that round shape, distinct margin, heterogeneous echogenicity, and presence of coagulation necrosis sign were independent predictive factors for metastasis. Two hundred eighty-five of the 664 lymph nodes (42.9%) having at least one metastatic feature of the four categories were pathologically proven metastatic, and 96.0% of lymph nodes (381/397) were proven not metastatic when all four categories were determined as benign. CONCLUSIONS Sonographic features of lymph nodes based on the new EBUS imaging classification may be helpful in the prediction of metastatic lymph nodes during EBUS-TBNA.


Respiratory Medicine | 2009

The role of EBUS-TBNA for the diagnosis of sarcoidosis – comparisons with other bronchoscopic diagnostic modalities

Takahiro Nakajima; Kazuhiro Yasufuku; Katsushi Kurosu; Yuichi Takiguchi; Taiki Fujiwara; Masako Chiyo; Kiyoshi Shibuya; Kenzo Hiroshima; Yukio Nakatani; Ichiro Yoshino

BACKGROUND The diagnosis of sarcoidosis requires both compatible clinical features and pathologic findings as a means to exclude other differential diagnoses. The utility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for diagnosis of sarcoidosis has been reported, although its indication remains unclear for cases of suspicious sarcoidosis. To clarify the role of EBUS-TBNA for the diagnosis of sarcoidosis, we compared three diagnostic modalities: EBUS-TBNA, transbronchial lung biopsy (TBLB) and bronchoalveolar lavage fluid analysis (BAL). METHODS Thirty-eight patients with suspicious sarcoidosis who had enlarged hilar and/or mediastinal lymph nodes on chest CT were retrospectively reviewed. Patients with malignancies or prior established diagnosis of sarcoidosis were excluded. BAL was initially performed followed by TBLB and finally EBUS-TBNA at the same setting. Microbacterial examinations were also performed from all samples. RESULTS Pathological findings compatible with sarcoidosis were obtained in 32 patients. The remaining 6 patients were diagnosed as one case each of chronic eosinophilic pneumonia, atypical mycobacterial infection and tuberculosis, and the remaining three were pathologically indefinite cases. Clinically, 35 patients were diagnosed with sarcoidosis. The diagnostic accuracy of sarcoidosis was significantly better by EBUS-TBNA (91.4%, p<0.001) compared to the other two modalities. According to chest roentgenogram classifications, there were 31 stage I patients and 4 stage II patients. For stage I patients, EBUS-TBNA was significantly better (90.3%, p<0.001), but each modality showed 100% accuracy for stage II patients. CONCLUSION It is recommended that EBUS-TBNA is added to the conventional diagnostic modalities for patients with suspicious stage I sarcoidosis on chest roentgenogram.


Journal of Heart and Lung Transplantation | 2011

Impact of extracorporeal life support on outcome in patients with idiopathic pulmonary arterial hypertension awaiting lung transplantation

Marc de Perrot; John Granton; Karen McRae; Marcelo Cypel; A. Pierre; Thomas K. Waddell; Kazuhiro Yasufuku; Michael Hutcheon; C. Chaparro; Lianne G. Singer; Shaf Keshavjee

BACKGROUND Our management of patients with idiopathic pulmonary arterial hypertension (iPAH) awaiting lung transplantation changed in 2006 with the introduction of extracorporeal life support (ECLS) as an option to bridge these patients to transplantation (BTT). METHODS To study the effect of this change on waiting list mortality and post-transplant outcome, 21 consecutive iPAH patients listed for lung transplantation between January 2006 and September 2010 (second cohort) were compared with 23 consecutive iPAH patients listed between January 1997 and December 2005 (first cohort). RESULTS Between the first and second cohort, the number of patients admitted to the hospital as BTT increased from 4% (1 of 23) to 48% (10 of 21; p = 0.0009). Six patients were BTT with ECLS in the second cohort, including 4 with the Novalung device (Novalung GmbH, Hechingen, Germany) connected as a pumpless oxygenating right-to-left shunt between the pulmonary artery and left atrium. While on the waiting list, 5 patients (22%) died in the first cohort and none in the second cohort (p = 0.03). Time on the waiting list decreased from 118 ± 85 to 53 ± 40 days between the first and second cohort (p = 0.004). After lung transplantation, the 30-day mortality was 16.7% in the first cohort and 9.5% in the second cohort (p = 0.5). The postoperative intensive care unit stay increased from 17 ± 13 to 36 ± 30 days between the first and second cohort (p = 0.02). The long-term outcome after lung transplantation remained similar between both cohorts. CONCLUSIONS Aggressive management with ECLS of iPAH patients awaiting lung transplantation could have a major impact to reduce the waiting list mortality. This may, however, be associated with longer intensive care unit stay after transplant.

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Shaf Keshavjee

University Health Network

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A. Pierre

University Health Network

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Marcelo Cypel

University Health Network

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