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Featured researches published by A. Takeda.


British Journal of Radiology | 2010

CT evaluations of focal liver reactions following stereotactic body radiotherapy for small hepatocellular carcinoma with cirrhosis: relationship between imaging appearance and baseline liver function

N. Sanuki-Fujimoto; A. Takeda; T. Ohashi; Etsuo Kunieda; Shogo Iwabuchi; Kentaro Takatsuka; Naoyoshi Koike; Naoyuki Shigematsu

This study aimed to assess the imaging appearances of focal liver reactions following stereotactic body radiotherapy (SBRT) for small hepatocellular carcinoma (HCC) and to examine relationships between imaging appearance and baseline liver function. We retrospectively studied 50 lesions in 47 patients treated with SBRT (30-40 Gy in 5 fractions) for HCC, who were followed up for more than 6 months. After SBRT, all patients underwent regular follow-ups with blood tests and dynamic CT scans. At a median follow-up of 18.1 months (range 6.2-43.7 months), all lesions but one were controlled. 3 density patterns describing focal normal liver reactions around HCC tumours were identified in pre-contrast, arterial and portal-venous phase scans: iso/iso/iso in 4 patients (Type A), low/iso/iso in 8 patients (Type B) and low/iso (or high)/high in 38 patients (Type C). Imaging changes in the normal liver surrounding the treated HCC began at a median of 3 months after SBRT, peaked at a median of 6 months and disappeared 9 months later. Liver function, as assessed by the Child-Pugh classification, was the only factor that differed significantly between reactions to treatment showing non-enhanced (Type A and B) and enhanced (Type C) appearances in CT. Hence, liver tissue with preserved function is more likely to be well enhanced in the delayed phase of a dynamic contrast-enhanced CT scan. The CT appearances of normal liver seen in reaction to the treatment of an HCC by SBRT were therefore related to background liver function and should not be misread as recurrence of HCC.


International Journal of Radiation Oncology Biology Physics | 2014

Threshold Doses for Focal Liver Reaction After Stereotactic Ablative Body Radiation Therapy for Small Hepatocellular Carcinoma Depend on Liver Function: Evaluation on Magnetic Resonance Imaging With Gd-EOB-DTPA

Naoko Sanuki; A. Takeda; Yohei Oku; Takahisa Eriguchi; Shuichi Nishimura; Yosuke Aoki; Tomikazu Mizuno; Shogo Iwabuchi; Etsuo Kunieda

PURPOSEnFocal liver reaction (FLR) appears on radiographic images after stereotactic ablative body radiation therapy (SABR) in patients with hepatocellular carcinoma (HCC) and chronic liver disease. We investigated the threshold dose (TD) of FLR and possible factors affecting the TD on gadoxetate acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI).nnnMETHODS AND MATERIALSnIn 50 patients who were treated with SABR for small HCC and followed up by MRI for >6 months, FLR, seen as a hypointense area, was evaluated on the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI. The follow-up MRI with the largest extent of FLR was fused to the planning computed tomography (CT) image, and patients with good image fusion concordance were eligible. After delineating the border of the FLR manually, a dose-volume histogram was used to identify the TD for the FLR. Clinical and volumetric factors were analyzed for correlation with the TD.nnnRESULTSnA total of 45 patients were eligible for analysis with a median image fusion concordance of 84.9% (range, 71.6-95.4%). The median duration between SABR and subsequent hepatobiliary phase MRI with the largest extent of FLR was 3 months (range, 1-6 months). The median TD for FLR was 28.0 Gy (range, 22.3-36.4 Gy). On univariate analysis, pre-treatment Child-Pugh (CP) score and platelet count were significantly correlated with the TD. On multiple linear regression analysis, CP score was the only parameter that predicted TD. Median TDs were 30.5 Gy (range, 26.2.3-36.4 Gy) and 25.2 Gy (range, 22.3-27.5 Gy) for patients with CP-A and CP-B disease, respectively.nnnCONCLUSIONnThe TD was significantly correlated with baseline liver function. We propose 30 Gy for CP-A disease and 25 Gy for CP-B disease in 5 fractions as TDs for FLR after SABR for patients with HCC and chronic liver disease. Use of these TDs will help to predict potential loss of liver tissue after SABR.


Hepatology Research | 2015

Influence of liver toxicities on prognosis after stereotactic body radiation therapy for hepatocellular carcinoma

Naoko Sanuki; A. Takeda; Yohei Oku; Takahisa Eriguchi; Shuichi Nishimura; Yosuke Aoki; Etsuo Kunieda

To better define clinically relevant non‐classic radiation‐induced liver disease (RILD) following stereotactic body radiotherapy (SBRT) in patients with small hepatocellular carcinoma (HCC).


Clinical Breast Cancer | 2013

Outcomes of Clinically Node-Negative Breast Cancer Without Axillary Dissection: Can Preserved Axilla Be Safely Treated With Radiation After a Positive Sentinel Node Biopsy?

Naoko Sanuki; A. Takeda; Atsushi Amemiya; Toru Ofuchi; Masashi Ono; Haruki Ogata; Ryo Yamagami; Jun Hatayama; Takahisa Eriguchi; Etsuo Kunieda

PURPOSEnWe analyzed whether axillary nodal irradiation could control clinically node-negative disease, including those patients with a positive sentinel lymph node biopsy (SLNB), most of whom received regional nodal irradiation. We also evaluated toxicity profiles that resulted from nodal irradiation.nnnPATIENTS AND METHODSnFrom 1988 to 2011, 2107 patients with cT1-T2N0M0 breast cancer underwent breast conservation therapy in the absence of axillary dissection: nx group (n = 1548), without any axillary surgery; the sn(-) group (n = 518), with a negative SLNB; and sn(+) group (n = 104), with a positive SLNB.nnnRESULTSnThe median follow-up times were 88, 56, and 55 months for the nx, sn(-), and sn(+) groups, respectively. The nx group had more risk factors than did the other 2 groups in terms of age, grade, or T stage. Ninety-eight percent of the sn(-)group received only tangent irradiation, and 100% and 83% of the sn(+) and nx group, respectively, received additional regional nodal irradiation. The 5-year cumulative incidences of axillary failure and regional nodal failure were 34, 3, and 0 (2.7%, 0.7%, and 0%; P = .02, log-rank test) and 57, 4, and 0 (4.4, 1%, and 0; P = .04), respectively. Overall survival rates in 5 years were 96.4%, 98.9%, and 97.6% (P = .03), respectively. Symptomatic but transient radiation pneumonitis developed in 31, 16, and 6 (2.0%, 3.1%, and 5.7%). Mild arm edema was observed in 1, 4, and 0 (0.06%, 0.8%, and 0%) in the nx, sn(-), sn(+) groups, respectively.nnnCONCLUSIONSnTreatment without axillary dissection showed excellent outcomes with negligible toxicity for patients with clinically node negative, including those with a positive SLNB. Regional nodal irradiation after a positive SLNB is a reasonable alternative to axillary dissection.


Breast Care | 2013

Axillary Irradiation with High Tangent Fields for Clinically Node-Negative Breast Cancer: Can 3-D Conformal Radiotherapy with a Field-in-Field Technique Better Control the Axilla?

Naoko Sanuki; A. Takeda; Atsushi Amemiya; Toru Ofuchi; Masato Ono; Haruki Ogata; Ryo Yamagami; Jun Hatayama; Takahisa Eriguchi; Etsuo Kunieda

Background: The target volume for postoperative breast irradiation is the remaining breast tissue, and the axillary region is not an intentional target volume. Patients and Methods: Between 2001 and 2009, eligible women with pT1-2cN0/pN0(sn) breast cancer underwent breast-conserving therapy without axillary dissection. Treatment outcomes between 2 radiotherapy planning groups, high tangent fields with 2-dimensional (2-D) simulation-based planning and 3-dimensional (3-D) computed tomography-based planning with a field-in-field technique, were compared. The correlating factors for axillary failure were also calculated. Results: In total, 678 patients were eligible. As of May 2009, the median follow-up times for the 2-D (n = 346) and 3-D (n = 332) groups were 94 and 52 months, respectively. Patient characteristics were balanced, except for a younger population in the 2-D group and more lymphovascular invasion in the 3-D group. On multivariate analysis, 2-D planning was the only risk factor for axillary failure. In the 2-D and 3-D groups, the 5-year cumulative incidences of axillary failure were 8 (3.1%) and 1 (0.3%) (log-rank p = 0.009), respectively. The respective 5-year overall survival rates were 97.4 and 98.4% (p = 0.4). Conclusion: High tangent irradiation with 3-D planning improved axillary control compared to that with 2-D planning, suggesting that optimizing axillary dose distribution may impact outcomes.


Journal of Radiotherapy in Practice | 2012

Multiple myeloma relapse in the irradiated liver: involvement of hepatocyte growth factor akin to that after hepatocyte transplantation

Akiko Uetake; A. Takeda; Naoyuki Shigematsu; Eiji Ikeda; Minako Kametaka; T. Ohashi; Etsuo Kunieda

We described a rare case of multiple myeloma in a 60-year-old man, in whom relapse limited to the irradiated area in the left lobe of the liver developed following radiotherapy for lesions in 11th and 12th thoracic spines. Immunohistochemical analysis revealed expression of hepatocyte growth factor (HGF) and hepatocyte growth factor receptor (c-Met) in the hepatocytes in the irradiated area of the liver. We speculate that the malignant plasma cells might have proliferated in response to local increase of HGF production in the irradiated liver. The role of HGF in the extraosseous spread of multiple myeloma and also under the experimental condition of hepatic transplantation is discussed.


International Journal of Radiation Oncology Biology Physics | 2007

Symptomatic Extrapulmonary Soft-Tissue Fibrosis Resulting From Hypofractionated Stereotactic Radiotherapy Pulmonary Nodular Lesion

Takatsugu Kawase; A. Takeda; E. Kunieda; Ryochi Ishibashi; Y. Kamikubo; Akitomo Sugawara; Toshio Ohashi; Junichi Fukada; Naoyuki Shigematsu; Atsushi Kubo


Japanese journal of clinical radiology | 2013

Pitfalls in stereotactic body radiation therapy for heptocellular carcinoma

N. Sanuki; A. Takeda; Y. Oku; T. Eriguchi; E. Kunieda


International Journal of Radiation Oncology Biology Physics | 2012

Outcomes of Clinically Node Negative Breast Cancer Without Axillary Dissection: Can the Preserved Axilla Be Safely Treated With Radiation After a Positive Sentinel Node Biopsy?

Naoko Sanuki; A. Takeda; Atsushi Amemiya; T. Ofuchi; M. Ono; H. Ogata; R. Yamagami; Takahisa Eriguchi; Etsuo Kunieda


International Journal of Radiation Oncology Biology Physics | 2008

Stereotactic Body Radiotherapy (SBRT) for Primary Lung Cancer at a Dose of 50 Gy per 5 Fractions to the Periphery of the Planning Target Volume (PTV) Calculated by a Superposition Algorithm

A. Takeda; Naoko Sanuki; Etsuo Kunieda; Toshio Ohashi; Yohei Oku; Toshiaki Takeda; Naoyuki Shigematsu; Atsushi Kubo

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