Keita Sasaki

Keita Sasaki


Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

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

Representative Publications

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10 November 2023 in Japanese Journal of Clinical Oncology
Verified
Journal Article
Closed access
RKRyosuke Kita
Ryosuke Kita
YYYoshitomo Yanagimoto
Yoshitomo Yanagimoto
HIHiroshi Imazeki
Hiroshi Imazeki
EBEisuke Booka
Eisuke Booka
TTTakahiro Tsushima
Takahiro Tsushima
SGStomach Cancer Study Group and Japan Esophageal Oncology Group of the Japan Clinical Oncology Group
Stomach Cancer Study Group and Japan Esophageal Oncology Group of the Japan Clinical Oncology Group
Treatment strategies for oesophagogastric junction adenocarcinoma have not been standardized despite its poor prognosis due to differences in the incidence rates between Western countries and Asia. This randomized Phase II/III trial was initiated in June 2023 to determine which neoadjuvant chemotherapy regimen, docetaxel, oxaliplatin and S-1 or fluorouracil, oxaliplatin and docetaxel, is a more promising treatment in Phase II and confirm the superiority of neoadjuvant chemotherapy with docetaxel, oxaliplatin and S-1 or fluorouracil, oxaliplatin and docetaxel followed by surgery and postoperative chemotherapy over upfront surgery and postoperative chemotherapy in terms of overall survival in patients with Clinical Stage III or IVA oesophagogastric junction adenocarcinoma in Phase III. A total of 460 patients, including 150 patients in Phase II and 310 patients in Phase III, are planned to be enrolled from 85 hospitals in Japan over 5 years. This trial has been registered in the Japan Registry of Clinical Trials as jRCTs031230182 (https://jrct.niph.go.jp/latest-detail/jRCTs031230182).

26 October 2023 in Japanese Journal of Clinical Oncology
Verified
Journal Article
Open access
PDF file
RKRyosuke Kita
Ryosuke Kita
SMSatoru Matsuda
Satoru Matsuda
MNMotoo Nomura
Motoo Nomura
RMRyunosuke Machida
Ryunosuke Machida
KSKeita Sasaki
Keita Sasaki
JGJapan Esophageal Oncology Group of the Japan Clinical Oncology Group
Japan Esophageal Oncology Group of the Japan Clinical Oncology Group
Although the efficacy of postoperative therapy with nivolumab after preoperative chemoradiotherapy for locally advanced oesophageal cancer has been proven in Western countries, the survival benefits of postoperative therapy after preoperative chemotherapy with docetaxel, cisplatin and 5-FU or cisplatin plus 5-FU as the Japanese standard therapy remain controversial. This randomized Phase III trial was designed to confirm the superiority of postoperative therapy with nivolumab over observation alone and S-1 over observation alone in patients with locally advanced oesophageal squamous cell carcinoma with no pathological complete response after preoperative chemotherapy followed by curative esophagectomy. A total of 450 patients will be enrolled from 56 hospitals in Japan over 5.5 years. The primary endpoint is relapse-free survival, and the secondary endpoints are disease-free survival, overall survival, adverse events and incremental cost-effectiveness ratio. This trial has been registered in the Japan Registry of Clinical Trials as jRCTs031230219 (https://jrct.niph.go.jp/latest-detail/jRCTs031230219).

1 November 2023 in BJS Open
Verified
Journal Article
Open access
THTadayoshi Hashimoto
Tadayoshi Hashimoto
STShunsuke Tsukamoto
Shunsuke Tsukamoto
KMKeiko Murofushi
Keiko Murofushi
YIYoshinori Ito
Yoshinori Ito
HHHidekazu Hirano
Hidekazu Hirano
YKYukihide Kanemitsu
Yukihide Kanemitsu
Background: Radical surgery is the standard treatment for rectal cancer, but can impact quality of life. Recently, the concept of total neoadjuvant therapy with a watch-and-wait strategy has been proposed in which patients with a cCR after total neoadjuvant therapy do not proceed to surgery. However, most investigations of a watch-and-wait strategy have reported cases where cCR was achieved coincidentally via total neoadjuvant therapy. The aim is to assess whether total neoadjuvant therapy is effective in early-stage rectal cancer in patients that achieve cCR and are offered a watch-and-wait strategy. Methods: JCOG2010 (TOWARd) is a multi-institutional, single-arm phase II/III confirmatory investigation of the safety and efficacy of total neoadjuvant therapy followed by a watch-and-wait strategy for rectal cancer. Key eligibility criteria include cT2–3 N0 M0 rectal adenocarcinoma, tumour diameter less than or equal to 5 cm, age 18–75 years, performance status 0–1, and no history of pelvic irradiation or rectal surgery. Total neoadjuvant therapy involves neoadjuvant chemoradiotherapy (capecitabine and radiotherapy: 45 Gy/25 fractions to the whole pelvis plus boost of 5.4 Gy/3 fractions to the primary tumour) followed by consolidation chemotherapy (four cycles of capecitabine/oxaliplatin). Patients will be re-staged every 8 weeks after total neoadjuvant therapy, and those who achieve cCR will undergo a watch-and-wait strategy, those with near complete response will undergo a watch-and-wait strategy or local resection, and those with an incomplete response will undergo radical surgery. The primary endpoint is the cCR rate in phase II and 5-year overall survival in phase III. Secondary endpoints include postoperative anal, urinary, and sexual function. A total of 105 patients (phase II, 40 patients; phase III, 65 patients) will be enrolled over 3.5 years. Conclusion: This trial will determine whether total neoadjuvant therapy and a watch-and-wait strategy is an effective alternative to radical surgery for early-stage rectal cancer in patients with cT2–3 N0 M0 and tumour size less than or equal to 5 cm. Registration number: jRCTs031220288 (https://jrct.niph.go.jp/en-latest-detail/jRCTs031220288).

19 August 2024 in Japanese Journal of Clinical Oncology
Verified
Journal Article
Open access
PDF file
KWKageaki Watanabe
Kageaki Watanabe
KSKeita Sasaki
Keita Sasaki
RMRyunosuke Machida
Ryunosuke Machida
JSJunichi Shimizu
Junichi Shimizu
YYYuki Yamane
Yuki Yamane
YOYuichiro Ohe
Yuichiro Ohe
Background: The treatment of lung cancer has made dramatic progress in the past decade, but due to the high cost of drugs, the total pharmaceutical cost has been rising explosively. There are currently no data available in Japan on which regimens are used, to what extent they are used, and what their total cost is. Methods: Sixty Japanese centers belonging to the Lung Cancer Study Group of the Japan Clinical Oncology Group were surveyed for information about the first-line treatment for advanced lung cancer in practice from July 2021 to June 2022. Three types of cancer were included: driver gene mutation-negative NSCLC, EGFR mutation-positive NSCLC, and extensive-stage small cell lung cancer (ES-SCLC). Results: Recent treatment costs for ICIs or ICI plus chemotherapy were about 20–55 times higher than those for conventional chemotherapy. Of the 3738 patients with driver gene aberration-negative NSCLC, 2573 (68.8%) received treatments with monthly cost of 500 000 Japanese yen (JPY) or more; 2555 (68.4%) received ICI therapy. Of the 1486 patients with EGFR mutation-positive NSCLC, 1290 (86.8%) received treatments with a monthly cost of 500 000 JPY or more; 1207 (81.2%) received osimertinib. ICI treatments with a monthly cost of 500 000 JPY or more were administered to 607 (56.3%) of 1079 patients with ES-SCLC. Elderly NSCLC patients received slightly more high-cost treatment than younger patients. Conclusion: Recent treatments cost many times more than conventional chemotherapy. This study revealed that high-cost treatments were widely used in advanced lung cancer and some of high-cost treatments were used despite the lack of clear evidence. Physicians should pay attention to the cost of treatments they use.

1 March 2008 in Toxicon
Verified
Journal Article
Closed access
KSKeita Sasaki
Keita Sasaki
YTYasunori Takayama
Yasunori Takayama
TTTatsuo Tahara
Tatsuo Tahara
KAKensaku Anraku
Kensaku Anraku
YIYushi Ito
Yushi Ito
NANorio Akaike
Norio Akaike

2 September 2024 in Japanese Journal of Clinical Oncology
Verified
Journal Article
Open access
PDF file
KMKAZUYA MOTOMURA
KAZUYA MOTOMURA
KSKeita Sasaki
Keita Sasaki
NSNarushi Sugii
Narushi Sugii
SYShigeru Yamaguchi
Shigeru Yamaguchi
HIHirotaka Inoue
Hirotaka Inoue
T(the Members of Japan Clinical Oncology Group Brain Tumor Study Group (JCOG-BTSG)
the Members of Japan Clinical Oncology Group Brain Tumor Study Group (JCOG-BTSG)
Background: This study aimed to investigate what treatment are selected for malignant brain tumors, particularly glioblastoma (GBM) and primary central nervous system lymphoma (PCNSL), in real-world Japan and the costs involved. Methods: We conducted a questionnaire survey regarding treatment selections for newly diagnosed GBM and PCNSL treated between July 2021 and June 2022 among 47 institutions in the Japan Clinical Oncology Group-Brain Tumor Study Group. We calculated the total cost and cost per month of the initial therapy for newly diagnosed GBM or PCNSL. Results: The most used regimen (46.8%) for GBM in patients aged ≤74 years was ‘Surgery + radiotherapy concomitant with temozolomide’. This regimen’s total cost was 7.50 million JPY (Japanese yen). Adding carmustine wafer implantation (used in 15.0%), TTFields (used in 14.1%), and bevacizumab (BEV) (used in 14.5%) to the standard treatment of GBM increased the cost by 1.24 million JPY for initial treatment, and 1.44 and 0.22 million JPY per month, respectively. Regarding PCNSL, ‘Surgery (biopsy) + rituximab, methotrexate, procarbazine, and vincristine (R-MPV) therapy’ was the most used regimen (42.5%) for patients of all ages. This regimen incurred 1.07 million JPY per month. The three PCNSL regimens based on R-MPV therapy were in ultra-high-cost medical care (exceeding 1 million JPY per month). Conclusions: Treatment of malignant brain tumors is generally expensive, and cost-ineffective treatments such as BEV are frequently used. We believe that the results of this study can be used to design future economic health studies examining the cost-effectiveness of malignant brain tumors.