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Featured researches published by Takashi Kawanaka.


Radiation Medicine | 2006

Chemoradiation Therapy for Cervical Cancer : Toxicity of Concurrent Weekly Cisplatin

Hitoshi Ikushima; K. Osaki; Shunsuke Furutani; Kyou Yamashita; Takashi Kawanaka; Yoshiomi Kishida; Seiji Iwamoto; Yoshihiro Takegawa; Takaharu Kudoh; Hiromu Nishitani

PurposeTo retrospectively evaluate the toxicity of concurrent weekly cisplatin and radiation therapy (RT) for locally advanced cervical cancer.Materials and MethodsBetween April 2001 and December 2004, 21 consecutive previously untreated patients with locally advanced cervical cancer were treated with concurrent chemoradiation therapy (CCRT) at the Tokushima University Hospital. Clinical stages were II: 5, III: 15, IVA: 1. External beam radiation therapy (EBRT) was delivered with 10 MV X-rays, 2 Gy fraction per day; total dose to the whole pelvis was 50 Gy. Iridium-192 high-doserate (HDR) intracavitary radiation therapy was performed with 10–30 Gy (median, 24 Gy) targeted at point A. Concurrent chemotherapy consisted of cisplatin, administered weekly at a dose of 40 mg/m2 for patients who were younger than 65 years and 30 mg/m2 for those 65 years or over. A maximum single dose of cisplatin, up to 70 mg/body, was administered in 5 cycles during EBRT.ResultsA total of 86 cycles of cisplatin were administered to the 21 patients, with a median of 4 cycles (range, 2–5). Severe hematological toxicity occurred in 18 patients (86%), including grade 3 in 17 patients (81%) and grade 4 in one patient (4.8%). Moderate or severe gastrointestinal toxicity occurred in 11 patients (52%), including grade 2 in 10 patients (48%) and grade 3 in one patient (4.8%). The grades of hematological toxicity were significantly greater in the 40 mg/m2 group than in the 30 mg/m2 group. All of the patients who were administered 40 mg/m2 of cisplatin developed grade 3 or greater hematological toxicity, including one patient with grade 4 toxicity. In the 30 mg/m2 group, 3 of 10 patients developed less than grade 3 toxicity, and all patients completed radiation therapy without interruption.ConclusionThe incidence of severe acute hematological toxicity was significantly higher in this study than in previously reported randomized controlled trials (RCTs), especially in the group of 40 mg/m2 cisplatin. A dose of 30 mg/m2 of cisplatin was considered to be feasible in weekly cisplatin and radiation therapy.


Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology | 2010

High-dose-rate brachytherapy for patients with maxillary gingival carcinoma using a novel customized intraoral mold technique

Takaharu Kudoh; Hitoshi Ikushima; Keiko Kudoh; Reiko Tokuyama; Kyohsuke Osaki; Shunsuke Furutani; Takashi Kawanaka; Akiko Kubo; Hiromu Nishitani; Eiichi Honda

OBJECTIVE The purpose of this study was to introduce a novel customized intraoral mold treatment for maxillary gingival carcinoma (UGC). STUDY DESIGN Two patients with UGC were treated as salvage therapy using this technique. The mold was designed to keep normal soft tissues adjacent to the tumor away from the radioactive source as much as possible, and it was shielded by lead. The radiation dose on the buccal mucosa and tongue was measured at the inner and outer surfaces of the intraoral mold before starting high-dose-rate brachytherapy by the remote afterloading system, and was reduced to almost one tenth. RESULTS The patient had no recurrence and no severe adverse effects on the normal soft tissue adjacent to the tumor until the end of the follow-up period. CONCLUSION High-dose-rate brachytherapy using the novel customized intraoral mold might be a treatment option of not only salvage therapy, but definitive therapy of UGC.


Radiation Medicine | 2008

Effective bladder preservation strategy with low-dose radiation therapy and concurrent intrarrterial chemotherapy for muscle-invasive bladder cancer

Hitoshi Ikushima; Seiji Iwamoto; Kyohsuke Osaki; Shunsuke Furutani; Kyoh Yamashita; Takashi Kawanaka; Akiko Kubo; Yoshihiro Takegawa; Takaharu Kudoh; Hiro-omi Kanayama; Hiromu Nishitani

PurposeThe aim of this study was to evaluate retrospectively the toxicity and response, bladder preservation, and survival of patients with muscle-invasive bladder cancer treated with multimodality therapy consisting of low-dose radiation therapy (RT) and concurrent intraarterial chemotherapy (IACT).Methods and materialsBetween November 1999 and July 2005, a total of 27 consecutive, previously untreated patients with muscle-invasive bladder cancer underwent transurethral bladder tumor resection followed by concurrent low-dose RT and IACT. Patients who achieved a complete response (CR) were followed up closely without further therapy, and patients who did not achieve a CR underwent further treatment.ResultsComplete response was achieved in 22 of 27 patients (81%). Of these 22 patients, 7 developed recurrences, and 3 died of their disease. In five patients who did not achieve CR, one died from bone metastases. The 3-year overall survival rate was 81%, with a median follow-up time of 27 months; and 22 of 27 patients (81%) with a preserved bladder were tumor-free at the last follow-up. Three patients (11%) developed grade 3 acute hematological toxicity.ConclusionMultimodality therapy consisting of low-dose RT and concurrent IACT for muscle-invasive bladder cancer can achieve survival rates similar to those in patients treated with radical cystectomy, with successful bladder preservation and minimal adverse effects.


Urologia Internationalis | 2015

Clinical Significance of Neoadjuvant Combined Androgen Blockade for More Than Six Months in Patients with Localized Prostate Cancer Treated with Prostate Brachytherapy.

Tomokazu Senzaki; Tomoharu Fukumori; Hidehisa Mori; Yoshito Kusuhara; Masatsugu Komori; Junichiro Kagawa; Tomoya Fukawa; Yasuyo Yamamoto; Kunihisa Yamaguchi; Masayuki Takahashi; Akiko Kubo; Takashi Kawanaka; Shunsuke Furutani; Hitoshi Ikushima; Hiro-omi Kanayama

Introduction: The aim of this study is to clarify the clinical significance of neoadjuvant combined androgen blockade (CAB) for ≥6 months in patients with localized prostate cancer. Patients and Methods: A total of 431 patients with localized prostate cancer who underwent prostate brachytherapy (BT) with or without neoadjuvant CAB for ≥6 months with mean follow-up time of 64.6 months (range 24-108 months) were evaluated retrospectively. Of those 431, 232 patients received BT in combination with neoadjuvant CAB for ≥6 months. Biochemical recurrence-free rates (BRFRs) in 364 patients with at least 3 years of follow-up were evaluated by log-rank test. Results: BRFR in patients with low-, intermediate- and high-risk prostate cancer were 98.1, 94.2 and 89.1%, respectively. In patients with intermediate-risk prostate cancer only, neoadjuvant CAB was significantly associated with BRFR (p = 0.0468). Especially in patients with intermediate-risk prostate cancer with radiation dose received by 90% of the prostate (D90) <180 Gy, neoadjuvant CAB exerted a favorable impact on BRFR (p = 0.0429). On multivariate analyses, neoadjuvant CAB and D90 were independent predictors of BRFR (p = 0.0061 and p < 0.0001, respectively). Conclusions: Neoadjuvant CAB for ≥6 months has a favorable impact on BRFR in patients with intermediate-risk prostate cancer, particularly in patients with relatively low radiation doses of D90.


Journal of Radiation Research | 2016

Multi-institutional retrospective analysis of learning curves on dosimetry and operation time before and after introduction of intraoperatively built custom-linked seeds in prostate brachytherapy

Hiromichi Ishiyama; Takefumi Satoh; Atsunori Yorozu; Shiro Saito; Masaaki Kataoka; Katsuyoshi Hashine; Ryuji Nakamura; Susumu Tanji; Koji Masui; Koji Okihara; Toshio Ohashi; Tetsuo Momma; Manabu Aoki; Kenta Miki; Masako Kato; Masashi Morita; Norihisa Katayama; Yasutomo Nasu; Takashi Kawanaka; Tomoharu Fukumori; Fumitaka Ito; Ryoichi Shiroki; Yuji Baba; Akito Inadome; Yasuo Yoshioka; Hitoshi Takayama; Kazushige Hayakawa

This multi-institutional retrospective analysis examined learning curves for dosimetric parameters and operation time after introduction of intraoperatively built custom-linked (IBCL) seeds. Data from consecutive patients treated with seed implantation before and after introduction of IBCL seeds (loose seed, n = 428; IBCL seed, n = 426) were collected from 13 centers. Dose–volume histogram parameters, operation times, and seed migration rates were compared before and after introduction of IBCL seeds. At the 1-month CT analysis, no significant differences were seen in dose to 90% of prostate volume between before and after IBCL seed introduction. No learning curve for dosimetry was seen. Prostate and rectal volume receiving at least 150% of prescription dose (V150 and RV150) were higher in the loose-seed group than in the IBCL-seed group. Operation time was extended by up to 10 min when IBCL seeds were used, although there was a short learning curve of about five patients. The percentage of patients with seed migration in the IBCL-seed group was one-tenth that in the loose-seed group. Our study revealed no dosimetric demerits, no learning curve for dosimetry, and a slightly extended operation time for IBCL seeds. A significant reduction in the rate of seed migration was identified in the IBCL-seed group.


The Journal of Medical Investigation | 2009

Risk factors for radiation pneumonitis caused by whole breast irradiation following breast-conserving surgery.

Akiko Kubo; Kyosuke Osaki; Takashi Kawanaka; Shunsuke Furutani; Hitoshi Ikushima; Hiromu Nishitani


Gynecologic Oncology | 2007

Radiation therapy for cervical cancer in the elderly.

Hitoshi Ikushima; Yoshihiro Takegawa; Kyohsuke Osaki; Shunsuke Furutani; Kyoh Yamashita; Takashi Kawanaka; Akiko Kubo; Takaharu Kudoh; Hiromu Nishitani


The Journal of Medical Investigation | 2008

Prognostic significance of HIF-2α expression on tumor infiltrating macrophages in patients with uterine cervical cancer undergoing radiotherapy

Takashi Kawanaka; Akiko Kubo; Hitoshi Ikushima; Toshiaki Sano; Yoshihiro Takegawa; Hiromu Nishitani


The Journal of Medical Investigation | 2008

Can Kampo therapy prolong the life of cancer patients

Yoshihiro Takegawa; Hitoshi Ikushima; Kyousuke Ozaki; Shunsuke Furutani; Takashi Kawanaka; Takaharu Kudoh; Masafumi Harada


The Journal of Medical Investigation | 2013

Changes of tumor and normal structures of the neck during radiation therapy for head and neck cancer requires adaptive strategy

Ryota Bando; Hitoshi Ikushima; Takashi Kawanaka; Takaharu Kudo; Motoharu Sasaki; Masahide Tominaga; Taro Kishi; Shunsuke Furutani; Akiko Kubo; Koichi Tamura

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Akiko Kubo

University of Tokushima

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K. Osaki

University of Tokushima

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