研究者業績

Shiroki Ryoichi

  (白木 良一)

Profile Information

Affiliation
Director, Fujita Medical Innovation Center
(Concurrent)Professor
Degree
Medicine(Sep, 1992, Fujita Health University)

Contact information
rshirokifujita-hu.ac.jp
Other name(s) (e.g. nickname)
Fujita Health University
J-GLOBAL ID
200901043122694037
researchmap Member ID
1000209006

1984 Graduated from Keio University School of Medicine
1992 Research fellow Washington Uviversity School of Medicine St.Louis USA
1995 Assistant Professor, Urology, Fujita health University School of Medicine
2000 Associate Professor, Urology, Fujita health University School of Medicine
2009 Professor, Urology, Fujita health University School of Medicine
2014 Professor & Chairman, Urology, Fujita health University School of Medicine
2016 Vice President, Urology, Fujita health University Hospital


Papers

 360
  • Kenji Zennami, Tetsuya Takimoto, Takuhisa Nukaya, Makoto Sumitomo, Mayu Takeda, Eiji Sugihara, Hideyuki Saya, Ryoichi Shiroki
    Cancer science, Mar 18, 2026  
    The clinical significance of comprehensive genomic profiling (CGP) has been established in metastatic castration-resistant prostate cancer (PC). However, the role of genomic profiling in localized PC remains unclear. In this exploratory study, we evaluated somatic genomic alterations in localized PC using an in-house CGP platform to examine their associations with biochemical recurrence (BCR) and recurrence-free survival (RFS) after radical prostatectomy. DNA extracted from surgical specimens of 314 patients with localized PC was analyzed for alterations in 164 cancer-related genes. Six genes (PTEN, BRCA2, POLD1, ERBB3, MYC, and SETD2) were more frequently altered in patients who developed BCR in exploratory analyses. Patients harboring alterations in any of these genes (n = 96) showed higher pathological T stage, increased BCR rates (27.1% vs. 6.4%), and inferior RFS compared with alteration-negative patients (n = 218; p < 0.001). In multivariate analysis, the presence of these alterations was independently associated with worse RFS. Among individual genes, BRCA2 alteration, and particularly BRCA2-SETD2 co-alteration, were associated with unfavorable outcomes, although the latter finding was based on a limited number of cases. In patients who developed BCR, alterations were associated with shorter PSA doubling time and poorer outcomes after salvage radiotherapy, particularly in margin-negative cases; however, these subgroup analyses were based on small numbers and should be interpreted as hypothesis-generating. These findings suggest that somatic genomic alterations identified at prostatectomy are associated with early recurrence in localized PC. Further validation in independent cohorts is required to determine whether genomic profiling may contribute to future risk stratification and management strategies.
  • Takuhisa Nukaya, Kiyoshi Takahara, Shingo Toyoda, Lan Inoki, Wataru Fukuokaya, Keiichiro Mori, Takehiro Iwata, Kensuke Bekku, Ryoichi Maenosono, Takuya Tsujino, Yosuke Hirasawa, Takafumi Yanagisawa, Takeshi Hashimoto, Kazumasa Komura, Motoo Araki, Kazutoshi Fujita, Yoshio Ohno, Ryoichi Shiroki
    International journal of urology : official journal of the Japanese Urological Association, 32(11) 1677-1685, Nov, 2025  Peer-reviewedLast author
    OBJECTIVES: We aimed to evaluate overall survival (OS) and determine the optimal timing of cytoreductive nephrectomy (CN) in patients with metastatic renal cell carcinoma (mRCC) receiving immune checkpoint inhibitor (ICI)-based therapy. METHODS: This retrospective study reviewed medical records of 447 patients with mRCC treated with ICI at multiple Japanese institutions between January 2018 and August 2023. From this cohort, 178 patients with lymph node or distant metastases received either cytoreductive nephrectomy (CN group; n = 72) or ICI therapy without cytoreductive nephrectomy (non-CN group; n = 106) as first-line treatment. RESULTS: Median progression-free survival was 15.7 months, and median overall survival was 58.1 months. CN significantly improved OS, with the CN group's median OS not reached, compared to 29.6 months in the non-CN group (p = 0.01). Deferred CN also showed improved survival outcomes. Poor prognostic factors for immediate CN included International Metastatic Renal Cell Carcinoma Database Consortium poor risk, sarcomatoid differentiation, and a high neutrophil-to-lymphocyte ratio. CONCLUSIONS: We developed a prognostic model to guide patient selection for CN, emphasizing the need for personalized treatment strategies.
  • Keiichiro Mori, Takafumi Yanagisawa, Tatsushi Kawada, Satoshi Katayama, Ryoichi Maenosono, Takuya Tsujino, Takeshi Hashimoto, Yosuke Hirasawa, Lan Inoki, Shingo Toyoda, Takuhisa Nukaya, Kiyoshi Takahara, Wataru Fukuokaya, Fumihiko Urabe, Takehiro Iwata, Kensuke Bekku, Yoshio Ohno, Ryoichi Shiroki, Kazutoshi Fujita, Haruhito Azuma, Motoo Araki, Takahiro Kimura
    International journal of clinical oncology, 30(11) 2335-2341, Nov, 2025  Peer-reviewed
    BACKGROUND: Despite durable benefits of ipilimumab and nivolumab in metastatic renal cell carcinoma (mRCC), early progressive disease (PD), defined as disease progression within 3 months, occurs, and its predictors remain unclear. We aimed to investigate the clinical factors associated with early PD in patients with mRCC treated with this regimen. METHODS: A retrospective analysis of a multi-institutional database identified 193 patients with mRCC treated with ipilimumab plus nivolumab. Logistic regression analyses assessed associations between clinical factors and early PD. RESULTS: During a median follow-up of 17 months, patients had median overall (OS) and progression-free survival (PFS) of 35 and 14 months, respectively. Objective response and PD rates were 49.9% and 24.9%, respectively. Patients with early PD had significantly worse OS than those with non-early PD (10 vs. 42 months; P = 0.0002). Multivariate analyses identified bone metastasis and performance status (PS) as independent indicators of early PD (P = 0.03 and 0.01, respectively). Early PD rates varied by metastatic site (lung, 19.3%; bone, 31.2%; brain, 10%; and liver, 30%). Patients with clear-cell RCC had a median OS of 48 months and PFS of 22 months. The identified variables of early PD were consistent across all patient populations evaluated. CONCLUSIONS: Bone metastasis and PS predict early PD in patients with mRCC treated with ipilimumab plus nivolumab, with antitumor effect of the regimen varying by metastatic site. Clarifying the characteristics of early PD may guide clinical decision-making in treatment selection.
  • 山崎 捷悟, 内本 泰三, 小村 和正, 福岡屋 航, 橋本 剛, 猿田 真庸, 高原 健, 藤田 和利, 木村 高弘, 大野 芳正, 白木 良一, 東 治人
    日本癌治療学会学術集会抄録集, 63回 O22-1, Oct, 2025  
  • Takuhisa Nukaya, Kiyohito Ishikawa, Ryoichi Shiroki
    Journal of general and family medicine, 26(5) 451-457, Sep, 2025  Peer-reviewedLast author
    BACKGROUND: Acute uncomplicated cystitis (AUC) is a urinary tract infection and is generally treated using antimicrobial therapy. Escherichia coli is the main causative agent of AUC. Recently, the prevalence of fluoroquinolone (FQ)-resistant-E. coli has demonstrated a noticeable increase. In this study, we aimed to investigate the effectiveness of appropriate antimicrobial treatment in AUC caused by E. coli in real-world clinical settings. METHODS: This retrospective cohort study reviewed the records of patients with AUC treated at the urology department of Minami Cooperative Hospital between April 2016 and December 2020. Effectiveness was defined as clinical improvement. RESULTS: The study cohort of 730 patients had a median age of 65.5 years (interquartile range, 57-78 years) and 23.2% were aged <55 years. E. coli was detected in 73.4% of patients, of whom 26.7% had levofloxacin (LVFX)-resistant strains. LVFX-resistant E. coli was associated with age ≥55 years and recurrent cases. Effectiveness was determined in 75.1% of cases, of which 75% complied with the Japanese or other international guidelines. The overall treatment effectiveness was highest with β-lactam (BL)/β-lactamase inhibitor (BLI) combinations (94.7%). The effectiveness of first- and third-generation cephalosporins (CPs) was 81.1-83.3%, and that of FQs and sulfamethoxazole-trimethoprim (ST) was 82.6-83.8%. For LVFX-resistant E. coli, the treatment effectiveness was highest (100%) with BL/BLI combinations, intermediate (75-81%) with first- and third-generation CPs and ST, and lowest (50%) with FQs. CONCLUSIONS: BL/BLI combinations had the highest effectiveness for the treatment of AUC.

Misc.

 140

Books and Other Publications

 5

Presentations

 1137

Research Projects

 15

作成した教科書、教材、参考書

 1
  • 件名(英語)
    スタデイメイト泌尿器科学 勝岡洋治 編 金芳堂
    終了年月日(英語)
    2009/11/01
    概要(英語)
    医学生並びに研修医、コメデイカル向けの泌尿器科学の教科書:泌尿器科手術などを分担執筆