研究者業績

保科 勇斗

ホシナ ハヤト  (HAYATO HOSHINA)

基本情報

所属
自治医科大学 医学部 腎泌尿器外科学講座 泌尿器科学部門 助教

研究者番号
80989301
ORCID ID
 https://orcid.org/0009-0009-5067-0241
J-GLOBAL ID
202301005181374020
researchmap会員ID
R000052593

論文

 15
  • Ibuki Tsuru, Satoru Taguchi, Ryo Tanaka, Taketo Kawai, Tomoyuki Kaneko, Yu Nakamura, Yoshifumi Miyauchi, Hayato Hoshina, Daisuke Obinata, Masashi Koshiba, Masashi Shiozaki, Jun Takahashi, Masato Kano, Akihiro Naito, Shohei Suda, Michio Noda, Nozomi Sugiyama, Takehiro Tanaka, Yukari Uemura, Jimpei Miyakawa, Jun Kamei, Shigenori Kakutani, Aya Niimi, Yuta Yamada, Yusuke Sato, Yukio Yamada, Hiroaki Nishimatsu, Takashi Murata, Sayuri Takahashi, Tappei Takada, Yoshiyuki Akiyama, Satoru Takahashi, Tetsuya Fujimura, Hiroshi Fukuhara, Tohru Nakagawa, Haruki Kume
    Japanese journal of clinical oncology 2026年7月9日  
    BACKGROUND: Triplet therapy with darolutamide and docetaxel has reshaped the treatment landscape of metastatic castration-sensitive prostate cancer (mCSPC). However, real-world evidence regarding its oncological outcomes and toxicity remains limited. METHODS: We retrospectively reviewed 112 consecutive patients with mCSPC who were treated with triplet therapy. A deep prostate-specific antigen (PSA) response was defined as a PSA level < 0.2 ng/ml or a ≥ 90% decline from baseline. Castration-resistant prostate cancer (CRPC)-free survival was used as the survival endpoint. Clinicopathological factors associated with CRPC-free survival were analysed using a Cox proportional hazards model. Treatment-related adverse events (AEs) were comprehensively documented by type and grade. RESULTS: During a median follow-up of 17.1 months, 15 patients developed CRPC and four died of prostate cancer; 1-year CRPC-free survival and overall survival rates were 89.8% (95% confidence interval, 83.9%-96.0%) and 98.8% (96.5%-100%), respectively. A deep PSA response was achieved in 73.2% of patients (PSA nadir <0.2 ng/ml) and in 96.4% (PSA ≥ 90% decline). In both the univariable and multivariable analyses, no baseline factor was significantly associated with CRPC-free survival. Grade ≥ 3 hematologic AEs occurred in 75.0% of patients. Among the 31 patients who discontinued docetaxel, 26 discontinued due to non-hematologic AEs. CONCLUSIONS: Triplet therapy demonstrated substantial clinical activity in real-world patients with mCSPC, with high rates of deep PSA response despite frequent AEs. These findings support the feasibility of triplet therapy in routine practice. Given the substantial toxicity burden, careful patient selection and proactive AE management remain important.
  • Satoshi Ando, Diego Andres Del Aguila Moraga, Hayato Hoshina, Hiroshi Kawahira, Toshiya Nakaguchi, Tetsuya Fujimura
    International journal of urology : official journal of the Japanese Urological Association 33(6) e70514 2026年6月  
    OBJECTIVES: To evaluate nerve-sparing status objectively using an artificial intelligence method applied to intraoperative images and to determine whether combining this assessment with preserved urethral length improves prediction of urinary continence recovery after robot-assisted radical prostatectomy. METHODS: We analyzed 195 patients with intraoperative still images from robot-assisted radical prostatectomy performed between May 2020 and 2022. Images were evaluated with a deep learning image classification model that determined whether the neurovascular bundle was preserved. Patients were categorized into two groups: those with both preserved urethral length of at least 26 mm and artificial intelligence-assessed neurovascular bundle preservation, and all other patients. The primary endpoint was time to urinary continence recovery. Kaplan-Meier analysis and Cox proportional hazards models were used. RESULTS: Artificial intelligence reclassified neurovascular bundle preservation in 60 of 195 patients (30.8%), including 48 cases of surgeon overestimation and 12 of underestimation. Patients who met both criteria had significantly better urinary continence recovery than the other patients, with higher continence rates at 30, 60, 90, and 365 days after surgery on log-rank testing. In multivariable Cox models, the combined factor independently predicted continence recovery at 60, 90, and 365 days, with hazard ratios of 1.99, 1.78, and 1.49 and corresponding 95% confidence intervals of 1.07-3.72, 1.07-2.95, and 1.09-2.04 (p values 0.03, 0.03, and 0.01, respectively). CONCLUSIONS: Objective evaluation of nerve-sparing status using artificial intelligence, when combined with preserved urethral length, improves prediction of early urinary continence recovery after robot-assisted radical prostatectomy and may provide an indicator of surgical quality.
  • Diego Andrés Del Aguila Moraga, Huitao Wang, Satoshi Ando, Hayato Hoshina, Hiroshi Kawahira, Yukihiro Nomura, Toshiya Nakaguchi
    International journal of computer assisted radiology and surgery 2026年2月12日  
    PURPOSE: Preserving neurovascular bundles (NVB) during robot-assisted radical prostatectomy (RARP) is vital for reducing postoperative complications such as urinary incontinence and erectile dysfunction. Building on our previous work in ensemble-based NVB classification, we propose the hybrid self-supervised teacher-student model (Hybrid T-S model) that leverages multi-task learning to predict NVB preservation in prostatectomy videos. METHODS: Our approach integrates a self-supervised framework (DINO) as an online self-distillation objective on multi-crop views to learn robust embeddings in a limited data setting, rather than as a stand-alone large-scale pretraining. A teacher encoder, which is an exponential moving average (EMA) of the student encoder, and a reconstruction decoder are trained jointly with a classification head in a single end-to-end framework. This model is evaluated on single frames from patients who underwent RARP surgery. RESULTS: Our experimental evaluation shows that the Hybrid T-S model outperforms previous NVB classification methods. This highlights the benefits of integrating self-supervised learning and multi-task objectives in this surgical context. We achieved an average accuracy of 86.55%, precision of 83.93%, recall of 90.73%, F1-score of 87%, and AUROC of 88.35%, based on fivefold cross-validation. CONCLUSION: Incorporating representation learning through self-distillation, classification, and reconstruction provides complementary signals that enhance the prediction of NVB preservation. Our Hybrid T-S model can assist surgeons in real decision-making and improve patient recovery.
  • Hayato Hoshina, Toru Sugihara, Ei-Ichiro Takaoka, Satoshi Ando, Haruki Kume, Tetsuya Fujimura
    International journal of urology : official journal of the Japanese Urological Association 33(1) e70357 2026年1月  
  • Hayato Hoshina, Toru Sugihara, Masayuki Kurokawa, Ei-Ichiro Takaoka, Satoshi Ando, Haruki Kume, Tetsuya Fujimura
    Current oncology (Toronto, Ont.) 32(6) 2025年6月7日  
    We assessed the efficacy of the lung immune prognostic index (LIPI) in predicting the progression of pathological T3 renal cell carcinoma (RCC). The LIPI scores of patients with pathological T3 RCC were calculated in the pre- and post-operative phases. Patients were divided into zero-point, one-point, and two-point groups according to their LIPI score and into the upstage and non-upstage groups according to the pre- and post-operative increase in LIPI score. Overall survival (OS) was evaluated using Kaplan-Meier curves stratified by group. Univariate and multivariate analyses of OS were performed via Cox proportional hazard regression analysis. LIPI scores were calculated in 80 patients wherein blood sampling data were available. The upstage and non-upstage groups comprised eight and seventy-two patients, respectively. Kaplan-Meier curves showed a significant difference in the pre- to post-operative LIPI score upstage group. LIPI score change was a poor prognostic factor using univariate analysis (OS: hazard ratio (HR) = 4.10, 95% confidence interval (CI) = 1.07-15.61, p = 0.038) and multivariate analysis (OS: HR = 4.38, 95% CI = 1.13-16.89, p = 0.031). An increase in the LIPI score in the pre-operative phase was a poor prognostic factor for pathological T3 RCC.

MISC

 57
  • 志賀淑之, 杉本真樹, 安部光洋, 錦見礼央, 保科勇斗, 米岡祐輔, 斎川周, 井上泰, 吉松正, 日下部将史, 亀山周二
    Japanese Journal of Endourology 31(2) 253-259 2018年9月  
    複合現実Mixed Reality (MR), 拡張現実Augmented Reality (AR), 仮想現実Virtual Reality (VR) 技術は, 医療画像解析における不可欠な技術として空間認識を改善させ, 画像手術支援に期待される有用なツールである. 医療行為での失敗や危機感を事前に繰り返し体験でき, 患者個別医療や繊細な医療技術の習熟に大きく貢献できる. 【目的】これらの技術を応用して術前患者画像を3Dホログラム化して, 泌尿器科手術におけるナビゲーション手術と手術教育の可能性を検討した. 【対象と方法】ロボットおよび開腹腎部分切除術ならびにロボット前立腺全摘除術を対象とした. 滅菌環境下で直感的なインターフェイス操作が可能な半透明型HMD方式のMRウェアラブルコンピュータHoloLens (Microsoft社) を使用した. 【結果】これまでの手術に比べて, VRならびにMRは腎部分切除術における腫瘍切除時間の短縮と出血量の低減に寄与した. 術者は腫瘍や血管周囲を含めた臓器解剖の距離感を直感的に体感でき, 周辺臓器の空間認識が改善され, 手術支援が大幅に効率化された. また助手やスタッフとイメージを共有でき, さらにHoloLensは術者目線の録画もできるため, 手術教育にも役立った. 【結論】VRならびにMRは手術ナビゲーションだけでなく, シミュレーションや教育にも有用なツールである.
  • 志賀 淑之, 安部 光洋, 斎川 周, 米岡 祐輔, 保科 勇斗, 井上 泰, 吉松 正, 亀山 周二, 杉本 真樹
    Japanese Journal of Endourology 30(3) 174-174 2017年11月  
  • 志賀 淑之, 乙供 太郎, 斎川 周, 米岡 祐輔, 保科 勇斗, 渡辺 洋志, 安部 光洋, 吉松 正, 亀山 周二
    泌尿器外科 30(臨増) 888-888 2017年5月  
  • 保科 勇斗, 米岡 祐輔, 斎川 周, 渡辺 洋志, 安部 光洋, 吉松 正, 志賀 淑之, 亀山 周二
    泌尿器外科 30(臨増) 914-914 2017年5月  
  • 渡辺 洋志, 保科 勇斗, 米岡 祐輔, 斎川 周, 安部 光洋, 吉松 正, 志賀 淑之, 亀山 周二
    日本泌尿器科学会総会 105回 PP08-06 2017年4月  
  • 齊川 周, 米岡 祐輔, 保科 勇斗, 渡辺 洋志, 安部 光洋, 吉松 正, 志賀 淑之, 亀山 周二, 堀内 啓
    日本泌尿器科学会総会 105回 PP22-03 2017年4月  
  • 志賀 淑之, 斎川 周, 保科 勇斗, 米岡 祐輔, 渡辺 洋志, 安部 光洋, 吉松 正, 亀山 周二
    Japanese Journal of Endourology 29(3) 190-190 2016年11月