Hiromichi Ishiyama

Prof. Hiromichi Ishiyama

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Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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2 August 2018 in Cancers
Verified
Journal Article
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HOHiroshi Onishi
Hiroshi Onishi
HYHideomi Yamashita
Hideomi Yamashita
YSYoshiyuki Shioyama
Yoshiyuki Shioyama
YMYasuo Matsumoto
Yasuo Matsumoto
KTKenji Takayama
Kenji Takayama
KKKengo Kuriyama
Kengo Kuriyama
Pretreatment pulmonary interstitial change (PIC) has been indicated as a risk factor of severe radiation pneumonitis (RP) following stereotactic body radiation therapy (SBRT) for early-stage lung cancer, but details of its true effect remain unclear. This study aims to evaluate treatment outcomes of SBRT for stage I non-small cell lung cancer in patients with PIC. A total of 242 patients are included in this study (88% male). The median age is 77 years (range, 55–92 years). A total dose of 40–70 Gy is administered in 4 to 10 fractions during a 4-to-25 day period. One, two, and three-year overall survival (OS) rates are 82.1%, 57.1%, and 42.6%, respectively. Fatal RP is identified in 6.9% of all patients. The percent vital capacity 10%), performance status of 2–4, presence of squamous cell carcinoma, clinical T2 stage, regular use of steroid before SBRT, and percentage predicting forced expiratory volume in one second (<70%) are associated with worse prognoses for OS. Our results indicate that fatal RP frequently occurs after SBRT for stage I lung cancer in patients with PIC.

1 May 2017 in Brachytherapy
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Journal Article
Closed access
HIHiromichi Ishiyama
Hiromichi Ishiyama
NKNobuhiko Kamitani
Nobuhiko Kamitani
HKHidemasa Kawamura
Hidemasa Kawamura
SKShingo Kato
Shingo Kato
MAManabu Aoki
Manabu Aoki
KHKazushige Hayakawa
Kazushige Hayakawa

1 September 2009 in International Journal of Radiation Oncology, Biology, Physics
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Journal Article
Closed access
HIHiromichi Ishiyama
Hiromichi Ishiyama
MKMasashi Kitano
Masashi Kitano
TSTakefumi Satoh
Takefumi Satoh
SKShouko Kotani
Shouko Kotani
MUMineko Uemae
Mineko Uemae
KHKazushige Hayakawa
Kazushige Hayakawa

1 April 2006 in Breast Cancer
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Journal Article
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HIHiromichi Ishiyama
Hiromichi Ishiyama
KNKeiji Niino
Keiji Niino
THTakaaki Hosoya
Takaaki Hosoya
KHKazushige Hayakawa
Kazushige Hayakawa
Purpose The present study aimed to determine the prevalence of subjective symptoms of late complications mainly caused by radiotherapy in breast-conserving therapy (BCT), and to identify patients and...

Verified
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HTHideyasu Tsumura
Hideyasu Tsumura
TSTakefumi Satoh
Takefumi Satoh
HIHiromichi Ishiyama
Hiromichi Ishiyama
KTKen-Ichi Tabata
Ken-Ichi Tabata
KTKouji Takenaka
Kouji Takenaka
MIMasatsugu Iwamura
Masatsugu Iwamura
Despite the absence of local prostate cancer recurrence, some patients develop distant metastases after prostate brachytherapy. We evaluate whether prostate brachytherapy procedures have a potential risk for hematogenous spillage of prostate cancer cells. Fifty-nine patients who were undergoing high-dose-rate (HDR) or low-dose-rate (LDR) brachytherapy participated in this prospective study. Thirty patients with high-risk or locally advanced cancer were treated with HDR brachytherapy after neoadjuvant androgen deprivation therapy (ADT). Twenty-nine patients with clinically localized cancer were treated with LDR brachytherapy without neoadjuvant ADT. Samples of peripheral blood were drawn in the operating room before insertion of needles (preoperative) and again immediately after the surgical manipulation (intraoperative). Blood samples of 7.5 mL were analyzed for circulating tumor cells (CTCs) using the CellSearch System. While no preoperative samples showed CTCs (0%), they were detected in intraoperative samples in 7 of the 59 patients (11.8%; preoperative vs. intraoperative, p = 0.012). Positive CTC status did not correlate with perioperative variables, including prostate-specific antigen (PSA) at diagnosis, use of neoadjuvant ADT, type of brachytherapy, Gleason score, and biopsy positive core rate. We detected CTCs from samples immediately after the surgical manipulation. Further study is needed to evaluate whether those CTCs actually can survive and proliferate at distant sites.

11 November 2013 in Journal of Radiation Research
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Journal Article
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HIHiromichi Ishiyama
Hiromichi Ishiyama
TSTakefumi Satoh
Takefumi Satoh
MKMasashi Kitano
Masashi Kitano
KTKen-Ichi Tabata
Ken-Ichi Tabata
SKShouko Komori
Shouko Komori
KHKazushige Hayakawa
Kazushige Hayakawa
The purpose of this study was to report the outcomes of high-dose-rate (HDR) brachytherapy and hypofractionated external beam radiotherapy (EBRT) combined with long-term androgen deprivation therapy (ADT) for National Comprehensive Cancer Network (NCCN) criteria-defined high-risk (HR) and very high-risk (VHR) prostate cancer. Data from 178 HR (n = 96, 54%) and VHR (n = 82, 46%) prostate cancer patients who underwent 192Ir-HDR brachytherapy and hypofractionated EBRT with long-term ADT between 2003 and 2008 were retrospectively analyzed. The mean dose to 90% of the planning target volume was 6.3 Gy/fraction of HDR brachytherapy. After five fractions of HDR treatment, EBRT with 10 fractions of 3 Gy was administered. All patients initially underwent ≥6 months of neoadjuvant ADT, and adjuvant ADT was continued for 36 months after EBRT. The median follow-up was 61 months (range, 25–94 months) from the start of radiotherapy. The 5-year biochemical non-evidence of disease, freedom from clinical failure and overall survival rates were 90.6% (HR, 97.8%; VHR, 81.9%), 95.2% (HR, 97.7%; VHR, 92.1%), and 96.9% (HR, 100%; VHR, 93.3%), respectively. The highest Radiation Therapy Oncology Group-defined late genitourinary toxicities were Grade 2 in 7.3% of patients and Grade 3 in 9.6%. The highest late gastrointestinal toxicities were Grade 2 in 2.8% of patients and Grade 3 in 0%. Although the 5-year outcome of this tri-modality approach seems favorable, further follow-up is necessary to validate clinical and survival advantages of this intensive approach compared with the standard EBRT approach.