K Yamada

Kanagawa Cancer Center, Yokohama, Kanagawa, Japan

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Publications (122)405.45 Total impact

  • International journal of radiation oncology, biology, physics 09/2014; 90(1):S322-S323. DOI:10.1016/j.ijrobp.2014.05.1069 · 4.18 Impact Factor
  • Interactive Cardiovascular and Thoracic Surgery 06/2014; 18(suppl 1):S19-S19. DOI:10.1093/icvts/ivu167.72 · 1.11 Impact Factor
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    ABSTRACT: AIM: To analyse the correlation between computed tomography (CT) findings of small lung adenocarcinomas and the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society Classification of Lung Adenocarcinoma. MATERIALS AND METHODS: A retrospective review of 300 lung adenocarcinoma lesions (size ≤20 mm) after surgical resection in 295 consecutive patients was performed. Tumours were defined as air-containing type if the ratio of the maximum dimension of the tumour on mediastinal windows to the maximum dimension of the tumour on lung windows was ≤50%, and as solid-density type if the ratio was >50%. The incidence between CT findings (air bronchogram, vascular involvement, pleural tags, notches, and spiculation) and pathological findings were investigated. RESULTS: Of the 142 air-containing lesions, 114 were adenocarcinoma in situ (AIS), 28 were minimally invasive adenocarcinoma (MIA), and none of the lesions were invasive adenocarcinoma. Of the 158 solid-density lesions, 30 were AIS, 24 were MIA, and 104 were invasive adenocarcinoma. Notches and pleural tags were commonly observed in cases of invasive adenocarcinoma (p < 0.05). CONCLUSIONS: In the air-containing type of small lung adenocarcinomas, AIS and MIA were observed but no cases of invasive adenocarcinoma were found. The presence of notches and pleural tags were a significant factor in invasive adenocarcinoma.
    Clinical Radiology 11/2012; 68(1). DOI:10.1016/j.crad.2012.09.002 · 1.66 Impact Factor
  • International Journal of Radiation OncologyBiologyPhysics 11/2012; 84(3):S607. DOI:10.1016/j.ijrobp.2012.07.1619 · 4.18 Impact Factor
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    T Osawa · M Mase · T Miyati · H Kan · K Demura · H Kasai · M Hara · Y Shibamoto · K Yamada
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    ABSTRACT: We have developed the delta-apparent diffusion coefficient (ADC), a new parameter of the water dynamics of brain tissue using MRI. Delta-ADC is the changes in regional ADC values of the brain during the cardiac cycle. The study included 6 idiopathic normal pressure hydrocephalus (iNPH) patients (iNPH group) and 12 healthy volunteers (control group). ECG-triggered single-shot diffusion echo planar imaging (b = 0 and 1,000 s/mm(2)) was used on a 1.5-T MRI. The delta-ADC image was calculated from the maximum minus the minimum ADC value of all cardiac phase images (20 phases) on a pixel-by-pixel basis. Delta-ADC values in the white matter of the frontal, temporal, and occipital lobe were obtained. Delta-ADC values in the iNPH group were significantly higher than those in the control group in all regions. ADC values in the iNPH were also significantly higher than those in the control group, but the differences in the ADC between the groups in each region were much lower than those for the delta-ADC. Although the changes in the delta-ADC and ADC values were similar, there was no significant correlation between the delta-ADC and the ADC. These results suggest that the ADC and the delta-ADC may reflect different kinds of water dynamics. The ADC depends on the water content in brain tissue. On the other hand, delta-ADC depends on not only the water content, but also on the degree of the fluctuation of the water molecules. Delta-ADC analysis makes it possible to obtain non-invasively new and more detailed information on the regional brain condition in iNPH.
    Acta neurochirurgica. Supplement 01/2012; 114:197-200. DOI:10.1007/978-3-7091-0956-4_38
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    ABSTRACT: We sought to evaluate radioisotope cisternography (RICG)-related postpuncture CSF leakage by MRI. We conducted a prospective 3-day imaging study. Ten patients with orthostatic headache and other symptoms underwent pre-RICG brain and spinal MRI, magnetic resonance myelography (MRM), RICG, and post-RICG spinal MRI and MRM. For RICG, we used a 25-gauge pencil point spinal needle at the L3/4 or L4/5 level after which subjects took bed rest for 2.5 hours. On pre-RICG MRI and MRM, none of the 10 patients showed CSF leakage. However, 5 subjects (50%) showed epidural abnormalities suggesting CSF leakage on MRI after lumbar puncture for RICG. On RICG and subsequent MRM, 4 of the subjects showed definite findings of CSF leakage and 1 showed minimal leakage. RICG carries a risk of iatrogenic CSF leakage even with careful puncturing using a fine needle. This leakage produces abnormal RICG and MRM findings at the lumbosacral level. Therefore, abnormal RICG findings restricted to the lumbosacral level should be carefully interpreted when diagnosing SIH.
    Neurology 11/2010; 75(19):1730-4. DOI:10.1212/WNL.0b013e3181fc2997 · 8.30 Impact Factor
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    ABSTRACT: Current international guidelines recommend the use of platinum-based chemotherapy with thoracic radiotherapy (TRT) for patients with locally advanced non-small-cell lung cancer (NSCLC). Patients with unresectable stage IIIA or IIIB NSCLC were treated with nedaplatin (NP) at 50 mg m(-2) and irinotecan (CPT) at 60 mg m(-2) on days 1 and 8 every 4 weeks for two to four cycles with concurrent TRT (2 Gy per day, total 60 Gy). All 35 patients were able to receive a total of 60 Gy. Adverse effects and events in chemotherapy with TRT were grade 3 or 4 anaemia, neutropenia and thrombocytopenia, which occurred in 3.0%, 32.8% and 6.0% of patients, respectively. There was no grade 3 pneumonitis or oesophagitis. Adverse effects and events in chemotherapy alone were mild. There was no treatment-related death. An overall response rate was 94.3%. The median progression-free and overall survivals were 13.0 and 36.0 months, respectively. The 5-year disease-free and overall survival rates were 25.7% and 40.0%, respectively. NP and CPT treatment with concurrent TRT is effective and safe for patients with unresectable, locally advanced NSCLC.
    British Journal of Cancer 10/2010; 103(9):1325-30. DOI:10.1038/sj.bjc.6605875 · 4.82 Impact Factor
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    ABSTRACT: Malignant pleural mesothelioma (MPM) is a rare but fatal tumour. Although most MPM patients show pleural effusion at even the early stage, it is hard to diagnose as MPM at the early stage because a sensitive and reliable diagnostic marker for MPM has not been found in plasma or pleural effusion. In this study, we investigated whether intelectin-1 was specifically contained in MPM cells and the pleural effusion of MPM patient by immunohistochemistry, western blotting, and enzyme-linked immunosorbent assay. Malignant pleural mesothelioma cell lines, but not lung adenocarcinoma cell lines, secreted intelectin-1. In immunohistochemistry, epithelioid-type MPMs, but neither pleura-invading lung adenocarcinomas nor reactive mesothelial cells near the lung adenocarcinomas, were stained with anti-intelectin antibodies. Pleural effusion of MPM patients contained a higher concentration of intelectin-1 than that of lung cancer patients. These results suggest that detection of intelectin-1 may be useful for a differential diagnosis of epithelioid-type MPM in immunohistochemistry and that a high concentration of intelectin-1 in pleural effusion can be used as a new marker for clinical diagnosis of MPM.
    British Journal of Cancer 08/2010; 103(4):517-23. DOI:10.1038/sj.bjc.6605786 · 4.82 Impact Factor
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    ABSTRACT: A latex agglutination test (LAT) was developed for detecting antibodies against avian influenza virus. The recombinant avian influenza virus nucleoprotein expressed in Escherichia coli was purified, coupled with latex beads, and used as an antigen for the LAT. The LAT was capable of detecting anti-avian influenza virus antibodies irrespective of the avian-influenza subtype, and in most cases, the results correlated with the results of an agar gel precipitation test (AGPT). However, in comparison with the AGPT, the LAT could detect the anti-avian influenza virus antibodies for a longer period of time after the infection. The nonspecific agglutination observed in uninfected chicken sera was resolved by pretreating the sera with dried chicken-liver powder for 1 h. The LAT is easy to perform, and even after considering the time required for pretreatment of the serum, the total time required for obtaining the results is reduced in comparison to the time required in the case of the AGPT. This easy and rapid LAT is considered to be useful for monitoring avian influenza virus infection in the field.
    Journal of virological methods 08/2009; 161(2):259-64. DOI:10.1016/j.jviromet.2009.06.021 · 1.88 Impact Factor
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    ABSTRACT: The infectivity of the H9N2 virus to MDCK cells was time-dependently inhibited by Cu(2+) at concentrations of 2.5-250 microM. In 25 microM Cu(2+) solution, the virus titer decreased by approximately 3 and 4 log within 3 and 6 h, respectively. Compared to Cu(2+), Zn(2+) was much less effective in virus inactivation. The H9N2 virus hemagglutinin activity was not affected by 2.5-250 microM Cu(2+). The H9N2 virus neuraminidase (NA) activity was drastically reduced by 25 mM Cu(2+), marginally reduced by 250 microM Cu(2+), and not affected by 25 microM Cu(2+). Thus, we found that copper ions suppress the infectivity of influenza virus at lower concentrations at which neither NA nor hemagglutination inhibition occurs. Electron microscopic analysis revealed morphological abnormalities of the Cu(2+)-treated H9N2 virus. Additional studies should be undertaken to clarify the mechanism underlying the antiviral effect of copper ions on influenza virus.
    Archives of Virology 02/2008; 153(8):1467-72. DOI:10.1007/s00705-008-0154-2 · 2.28 Impact Factor
  • Noritaka Aihara · M. Mase · K. Yamada
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    ABSTRACT: BackgroundWe reviewed our experience and assessed whether clipping or coiling affected the incidence of symptomatic vasospasm. MethodWe treated ruptured aneurysm primarily by clipping between January 1996 and September 1997 (n=52: 1st period), and primarily by coiling between October 1997 and December 2000 (n=31: 2nd period). For the period between January 2001 and December 2004 (3rd period), we selected either clipping or coiling based on the radiological findings and the patients’ condition. Consequently, clipping treated 13 patients and coiling treated 6 patients. We analyzed the clearance rates of subarachnoid clots chronologically on computerized tomography (CT) scan and neuron specific enolase (NSE) levels in cerebrospinal fluid (CSF) as an index of brain damage. FindingsSymptomatic vasospasm occurred in 20 (38.5%) patients in the 1st period and 5 (16.1%) patients in the 2nd period. Subarachnoid clots on CT scan disappeared earlier in patients in the 2nd period than in patients in the 1st period. The level of NSE in CSF transiently increased in patients in the 1st period. Because coiling mostly treated patients with Hunt and Kosnik grade 4 in the 3rd period, the incidence of symptomatic vasospasm was high (3/6=50%) in the patients treated by coiling. ConclusionsWe suggest that, in patients treated by coiling, the earlier washout of subarachnoid clots and possibly less brain damage from surgical manipulation decreased the incidence of symptomatic vasospasm. However, the decreased invasiveness is of limited advantage for patients with in poor grade SAH.
    Cerebral Vasospasm, 12/2007: pages 343-345;
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    ABSTRACT: We conducted a feasibility study to examine whether small numbers of cancer cells could be utilised for analysis of the EGFR gene status using the loop-hybrid mobility shift assay, which is a modified heteroduplex technique. Cytology specimens obtained by transbronchial abrasion were successfully used for analysis of the EGFR gene status in 50 of 52 (96.2%) patients diagnosed with class V non-small-cell carcinoma. Furthermore, the relationship between the EGFR gene status and clinical outcome was analysed in 25 patients treated with gefitinib. Overall, 10 of 11 patients with EGFR mutations in exon 19 or 21 showed tumour regression with gefitinib treatment, compared to only two of 14 patients with wild-type EGFR. The response rate was significantly higher in the EGFR mutation group than in the wild-type EGFR group (90.9 vs 14.3%, P=0.00014). Logistic regression analysis revealed that EGFR mutations in cytology specimens represented an independent predictor of the gefitinib response. The overall and progression-free survivals were significantly longer in the EGFR mutation group than in the wild-type EGFR group (P<0.05). In conclusion, cytology specimens could be useful for analysing the EGFR status in the majority of patients with non-small-cell lung cancer to determine whether they are likely to benefit from gefitinib treatment.
    British Journal of Cancer 11/2006; 95(8):1070-5. DOI:10.1038/sj.bjc.6603396 · 4.82 Impact Factor
  • H. Ito · H. Nakayama · K. Watanabe · H. Saito · F. Oshita · K. Yamada · K. Noda
    Lung Cancer 07/2005; 49. DOI:10.1016/S0169-5002(05)81377-7 · 3.74 Impact Factor
  • Lung Cancer 07/2005; 49. DOI:10.1016/S0169-5002(05)81488-6 · 3.74 Impact Factor
  • Lung Cancer 07/2005; 49. DOI:10.1016/S0169-5002(05)80740-8 · 3.74 Impact Factor
  • Lung Cancer 07/2005; 49. DOI:10.1016/S0169-5002(05)81165-1 · 3.74 Impact Factor
  • M Mase · T Miyati · K Yamada · H Kasai · M Hara · Y Shibamoto
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    ABSTRACT: The aim of this study is to clarify biophysics of normal pressure hydrocephalus (NPH) based on non-invasive intracranial compliance measurement using magnetic resonance imaging (MRI). Patients with NPH after subarachnoid hemorrhage (NPH group, n = 5), brain atrophy or asymptomatic ventricular dilation (VD group, n = 5), and healthy volunteers (control group, n = 12) were included in this study. Net blood flow (bilateral internal carotid and vertebral arteries, and jugular veins) and cerebrospinal fluid (CSF) flow in subarachnoid space at the C2 level of cervical vertebra were measured using phase-contrast cine MRI. CSF pressure gradient and intracranial volume changes during a cardiac cycle were calculated based on Alperin's method. Compliance index (Ci = delta V/delta P) was obtained from the maximum pressure gradient and volume changes. Pressure volume response (PVR) was measured in the NPH group during a shunt operation. Ci in the NPH group was the lowest among the three studies groups. No difference was found between the control and VD groups. There was a linear correlation between Ci and PVR. In conclusion, intracranial compliance can be determined by cine MRI non-invasively. It is well known that NPH has relatively low intracranial compliance, this non-invasive method can be used for the diagnosis of NPH.
    Acta neurochirurgica. Supplement 02/2005; 95:303-6.
  • H Katano · K Kato · A Umemura · K Yamada
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    ABSTRACT: Three-dimensional CT angiography (3D-CTA) was employed for perioperative evaluation of carotid endarterectomy (CEA) as an alternative to conventional angiography. A total of 62 carotid arteries were examined before and after CEA, 26 with an early 3D-CT system and 36 with multidetector helical CT allowing sophisticated reconstruction by a personal workstation. In addition to patients who had undergone conventional angiography at other institutes, 10 subjects underwent CEA on the basis of 3D-CTA findings alone. The findings provided detailed information with an excellent view of carotid stenoses. Volume rendering images comprehensively visualized lesions and surrounding structures as well as calcifications, which were also well depicted by maximum intensity projection images. Evaluation of the cerebral circulation is one problem that still requires solution, although cerebral vessels were delineated by 3D-CTA. One patient experienced transient hemiparesis, but no significant permanent deficit. We conclude that 3D-CTA is a safe and accurate modality that is a practical alternative to conventional perioperative angiography.
    British Journal of Neurosurgery 05/2004; 18(2):138-48. DOI:10.1080/02688690410001680993 · 0.95 Impact Factor
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    ABSTRACT: A 43-year-old-woman who had sever anterior chest pain visited our hospital on April 3, 2000. A well-defined abnormal shadow was seen in the middle and lower field of the right lung on chest X-ray. Computed tomography showed a large fat density mass in the right pleural cavity with a septum enhanced by contrast medium. Percutaneous needle biopsy revealed lipoma or liposarcoma. Complete resection could be done with combined resection of right lung, lpericardium, parietal pleura and diaphragm. Final histologic diagnosis was well differentiated liposarcoma. There are few reports of liposarcoma arising in the thoracic cavity, we present our case and review the 23 cases reported from the Japanese literatures.
    Kyobu geka. The Japanese journal of thoracic surgery 08/2003; 56(7):593-6.
  • A Umemura · K Yamada
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    ABSTRACT: B-mode ultrasonography has been used to evaluate cervical carotid artery lesions. Recently, the technology for direct visualization of blood reflectors has made B-mode flow imaging (B-flow) possible without the limitations of Doppler technology. We evaluated the efficacy of B-flow in examining the cervical carotid artery. Sixty patients with ischemic cerebrovascular disease were examined. Conventional B-mode imaging and blood flow images by power Doppler imaging (PDI) and B-flow were obtained. B-flow enabled simultaneous imaging of tissue and blood flow. Compared with PDI, B-flow provided higher spatial resolution and higher frame rate hemodynamic imaging. Consequently, a clear definition of the vessel lumen was obtained even in the stenotic portion of the carotid artery. In evaluating the degree of carotid stenosis, B-flow measurement agreed with digital subtraction angiography as well as PDI measurement. In addition, bloodstream swirl at the site of wall ulceration or vascular elongation was observed. B-flow was prominent in visualizing hemodynamic flow and detection of stenotic lesion in the cervical carotid artery. Combined with conventional B-mode technique, B-flow seems to be useful in evaluating carotid stenosis.
    Stroke 10/2001; 32(9):2055-7. DOI:10.1161/hs0901.095648 · 6.02 Impact Factor

Publication Stats

1k Citations
405.45 Total Impact Points

Institutions

  • 1993–2012
    • Kanagawa Cancer Center
      Yokohama, Kanagawa, Japan
  • 1997–2010
    • Nagoya City University
      • • Department of Neurosurgery (Hospital)
      • • Department of Radiology
      • • Department of Neurosurgery
      Nagoya, Aichi, Japan
  • 2008–2009
    • Obihiro University of Agriculture and Veterinary Medicine
      • Research Center for Animal Hygiene and Food Safety e
      Obibiro, Hokkaidō, Japan
  • 2005
    • The University of Tokushima
      • Department of Optical Science and Technology
      Tokusima, Tokushima, Japan
  • 2001
    • Shizuoka Hospital
      Sizuoka, Shizuoka, Japan
  • 2000
    • Nagoya University
      • Division of Neurosurgery
      Nagoya-shi, Aichi-ken, Japan
  • 1996–1998
    • Fujitsu Ltd.
      • File Memory Laboratory
      Kawasaki Si, Kanagawa, Japan
  • 1988–1998
    • The University of Tokyo
      • Division of Internal Medicine
      Edo, Tōkyō, Japan
    • Setsunan University
      Ōsaka, Ōsaka, Japan
  • 1992–1996
    • Oita University
      • Department of Physiology
      Ōita, Ōita, Japan