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Featured researches published by Wasaburo Koizumi.


Lancet Oncology | 2008

S-1 plus cisplatin versus S-1 alone for first-line treatment of advanced gastric cancer (SPIRITS trial): a phase III trial

Wasaburo Koizumi; Hiroyuki Narahara; Takuo Hara; Akinori Takagane; Toshikazu Akiya; Masakazu Takagi; Kosei Miyashita; Takashi Nishizaki; Osamu Kobayashi; Wataru Takiyama; Yasushi Toh; Takashi Nagaie; Seiichi Takagi; Yoshitaka Yamamura; Kimihiko Yanaoka; Hiroyuki Orita; Masahiro Takeuchi

BACKGROUND Phase I/II clinical trials of S-1 plus cisplatin for advanced gastric cancer have yielded good responses and the treatment was well tolerated. In this S-1 Plus cisplatin versus S-1 In RCT In the Treatment for Stomach cancer (SPIRITS) trial, we aimed to verify that overall survival was better in patients with advanced gastric cancer treated with S-1 plus cisplatin than with S-1 alone. METHODS In this phase III trial, chemotherapy-naive patients with advanced gastric cancer were enrolled between March 26, 2002, and Nov 30, 2004, at 38 centres in Japan, and randomly assigned to S-1 plus cisplatin or S-1 alone. In patients assigned to S-1 plus cisplatin, S-1 (40-60 mg depending on patients body surface area) was given orally, twice daily for 3 consecutive weeks, and 60 mg/m(2) cisplatin was given intravenously on day 8, followed by a 2-week rest period, within a 5-week cycle. Those assigned to S-1 alone received the same dose of S-1 twice daily for 4 consecutive weeks, followed by a 2-week rest period, within a 6-week cycle. The primary endpoint was overall survival. Secondary endpoints were progression-free survival, proportions of responders, and safety. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00150670. FINDINGS 305 patients were enrolled; seven patients were ineligible or withdrew consent, therefore, 148 patients were assigned to S-1 plus cisplatin and 150 patients were assigned to S-1 alone. Median overall survival was significantly longer in patients assigned to S-1 plus cisplatin (13.0 months [IQR 7.6-21.9]) than in those assigned to S-1 alone (11.0 months [5.6-19.8]; hazard ratio for death, 0.77; 95% CI 0.61-0.98; p=0.04). Progression-free survival was significantly longer in patients assigned to S-1 plus cisplatin than in those assigned to S-1 alone (median progression-free survival 6.0 months [3.3-12.9] vs 4.0 months [2.1-6.8]; p<0.0001). Additionally, of 87 patients assigned S-1 plus cisplatin who had target tumours, one patient had a complete response and 46 patients had partial responses, ie, a total of 54% (range 43-65). Of 106 patients assigned S-1 alone who had target tumours, one patient had a complete response and 32 had partial responses, ie, a total of 31% (23-41). We recorded more grade 3 or 4 adverse events including leucopenia, neutropenia, anaemia, nausea, and anorexia, in the group assigned to S-1 plus cisplatin than in the group assigned to S-1 alone. There were no treatment-related deaths in either group. INTERPRETATION S-1 plus cisplatin holds promise of becoming a standard first-line treatment for patients with advanced gastric cancer.


Oncology | 2000

Phase II Study of S-1, a Novel Oral Derivative of 5-Fluorouracil, in Advanced Gastric Cancer

Wasaburo Koizumi; Minoru Kurihara; Shuji Nakano; Koichi Hasegawa

Purpose: To assess the efficacy and safety of S-1, a novel oral fluoropyrimidine derivative, we conducted a multicenter late phase II study in patients with advanced gastric cancer. Patients and Methods: Fifty-one patients who had received no previous chemotherapy were enrolled. Fifty patients were eligible for efficacy and safety analyses. The overall response was evaluated for the 43 patients who had metastatic lesions. S-1 was administered orally after breakfast and dinner for 28 days, followed by a 14-day break. The dosages were assigned according to the patients’ body surface area (BSA): BSA <1.25 m2, 40 mg; 1.25–1.5 m2, 50 mg, and BSA ≥1.5 m2, 60 mg, twice daily. Results: The overall response to treatment was evaluated as partial response in 19 of the 43 patients (44%; 95% confidence interval 30–59%). The median survival time in all patients was 207 days with 1- and 2-year survival rates of 36.0 and 14.0%, respectively. Grade 3 adverse reactions included decreased hemoglobin values in 2 patients, leukopenia, neutropenia and diarrhea in 1 patient each. No other grade 4 or unexpected adverse reactions were seen. Conclusions: S-1 is effective against advanced gastric cancer. This oral treatment is suitable for outpatients because of its mild toxicity. Further therapeutic benefits are likely to be obtained by combining S-1 with other chemotherapeutic agents.


Lancet Oncology | 2009

Fluorouracil versus combination of irinotecan plus cisplatin versus S-1 in metastatic gastric cancer: a randomised phase 3 study

Narikazu Boku; Seiichiro Yamamoto; Haruhiko Fukuda; Kuniaki Shirao; Toshihiko Doi; Akira Sawaki; Wasaburo Koizumi; Hiroshi Saito; Kensei Yamaguchi; Hiroya Takiuchi; Junichiro Nasu; Atsushi Ohtsu

BACKGROUND The best chemotherapy regimen for metastatic gastric cancer is uncertain, but promising findings have been reported with irinotecan plus cisplatin and S-1 (tegafur, 5-chloro-2,4-dihydropyrimidine, and potassium oxonate). We aimed to investigate the superiority of irinotecan plus cisplatin and non-inferiority of S-1 compared with fluorouracil, with respect to overall survival, in patients with metastatic gastric cancer. METHODS We undertook a phase 3 open label randomised trial in 34 institutions in Japan. We enrolled patients aged 20-75 years or younger, who had histologically proven gastric adenocarcinoma, and randomly assigned them by minimisation to receive either: a continuous infusion of fluorouracil (800 mg/m(2) per day, on days 1-5) every 4 weeks (n=234); intravenous irinotecan (70 mg/m(2), on days 1 and 15) and cisplatin (80 mg/m(2), on day 1) every 4 weeks (n=236); or oral S-1 (40 mg/m(2), twice a day, on days 1-28) every 6 weeks (n=234). The primary endpoint was overall survival. Analyses were done by intention to treat. This study is registered with Clinicaltrials.gov, number NCT00142350, and with UMIN-CTR, number C000000062. FINDINGS All randomised patients were included in the primary analysis. Median overall survival was 10.8 months (IQR 5.7-17.8) for individuals assigned fluorouracil, 12.3 months (8.1-19.5) for those allocated irinotecan plus cisplatin (hazard ratio 0.85 [95% CI 0.70-1.04]; p=0.0552), and 11.4 months (6.4-21.3) for those assigned S-1 (0.83 [0.68-1.01]; p=0.0005 for non-inferiority). Three treatment-related deaths occurred in the irinotecan plus cisplatin group and one was recorded in the S-1 group. INTERPRETATION S-1 is non-inferior to fluorouracil and, in view of the convenience of an oral administration, could replace intravenous fluorouracil for treatment of unresectable or recurrent gastric cancer, at least in Asia. Irinotecan plus cisplatin is not superior to fluorouracil in this setting.


British Journal of Cancer | 2003

Phase I/II study of S-1 combined with cisplatin in patients with advanced gastric cancer

Wasaburo Koizumi; S Tanabe; Katsunori Saigenji; Atsushi Ohtsu; Narikazu Boku; F Nagashima; Kuniaki Shirao; Yasuhiro Matsumura; Masahiro Gotoh

A dose-escalation study of cisplatin (CDDP) combined with S-1, a new oral dihydropyrimidine dehydrogenase inhibitory fluoropyrimidine, was performed to determine the maximum-tolerated dose (MTD), recommended dose (RD), dose-limiting toxicities (DLTs), and objective response rate (RR) in advanced gastric cancer (AGC). S-1 was given orally at 40 mg m−2 b.i.d. for 21 consecutive days following a 2-week rest. CDDP was planned to be given intravenously on day 8, at a dose of 60, 70, or 80 mg m−2 depending on the DLT. Treatment was repeated every 5 weeks, unless disease progression was observed. In the phase I portion, the MTD of CDDP was presumed to be 70 mg m−2, because 33.3% of patients (2/6) developed DLTs, mainly neutropenia. Therefore, the RD of CDDP was estimated as 60 mg m−2. In the phase II portion, 19 patients including six patients of the RD phase I portion were evaluated. The median administered courses was four (range: 1–8). The incidences of severe (grades 3–4) haematological and nonhaematological toxicities were 15.8 and 26.3%, respectively, but all were manageable. The RR was 74% (14/19, 95% confidence interval: 54.9−90.6%), and the median survival day was 383. This regimen is considered to be active against AGC with acceptable toxicity.


Journal of Clinical Oncology | 2006

Pharmacodynamic Studies of Gefitinib in Tumor Biopsy Specimens From Patients With Advanced Gastric Carcinoma

Federico Rojo; Josep Tabernero; Joan Albanell; Eric Van Cutsem; Atsushi Ohtsu; Toshihiko Doi; Wasaburo Koizumi; Kuniaki Shirao; Hiroya Takiuchi; S. Ramon y Cajal; José Baselga

PURPOSE Epidermal growth factor receptor (EGFR) is highly expressed in some gastric cancers and is implicated in cancer cell growth and proliferation. The objective of this study was to assess the in situ biologic activity of the EGFR tyrosine kinase inhibitor gefitinib in gastric tumor samples in a phase II study. METHODS Patients with previously treated stage IV adenocarcinoma of the stomach or gastroesophageal junction were randomly assigned to receive gefitinib (250 or 500 mg/d). Tumor biopsies, obtained at screening and on day 28 of treatment, were assessed for biomarker expression using immunohistochemistry and analysis of apoptosis. RESULTS One hundred sixteen tumor samples from 70 patients were available, 70 were baseline and 46 were on-therapy biopsies. At baseline, levels of EGFR expression significantly correlated with levels of phosphorylated EGFR (pEGFR; P < .001) and Ki67 expression (P = .011), but not with phosphorylated mitogen-activated protein kinase (pMAPK). After gefitinib treatment, levels of pEGFR in tumor cells were significantly reduced (P = .001); this was not the case for pMAPK and phosphorylated Akt (pAkt). However, in some cases gefitinib inhibited pAkt and these tumors had enhanced apoptosis. Likewise, there was a significant correlation between increased exposure to geftinib and enhanced apoptosis. CONCLUSION Gefitinib reached the tumors at concentrations sufficient to inhibit EGFR activation in advanced gastric carcinoma patients, although this did not translate into clinical benefit. Overall, intratumoral phosphorylation of MAPK and Akt was not significantly inhibited by gefitinib. However, the finding that decreases in pAkt correlated with enhanced apoptosis deserves further exploration.


Gastrointestinal Endoscopy | 2002

Clinical outcome of endoscopic aspiration mucosectomy for early stage gastric cancer

Satoshi Tanabe; Wasaburo Koizumi; Hiroyuki Mitomi; Hisao Nakai; Satoshi Murakami; Shizuka Nagaba; Mitsuhiro Kida; Masahito Oida; Katsunori Saigenji

BACKGROUND Endoscopic mucosal resection is an established treatment option for early stage gastric cancer. However, several problems with endoscopic mucosal resection remain to be solved, such as appropriate treatment for recurrence and incomplete tumor resection. The outcome for patients undergoing endoscopic aspiration mucosectomy (endoscopic mucosal resection) by a modification of the cap-fitted technique was evaluated retrospectively to determine factors associated with complete resection and tumor recurrence. METHODS Endoscopic mucosal resection was performed in 106 patients with early stage gastric cancers up to 20 mm in diameter that were well or moderately differentiated adenocarcinoma. All were superficial lesions without ulceration, distinct signs of submucosal invasion, or a poorly demarcated border. En bloc (tumors <10 mm in diameter) or piecemeal (tumors 10-20 mm in diameter) resection was performed. Follow-up endoscopy was performed at 2, 6, 12, 18, and 24 months and thereafter once per year. Outcome and factors associated with complete resection and tumor recurrence were assessed retrospectively. RESULTS Sixty-eight patients (64%) underwent en bloc resection and 38 (36%) piecemeal resection. The mean longest dimension (SD) of the resected lesions was significantly greater after piecemeal resection (12.3 [4.0] mm) than after en bloc resection (7.6 [4.0] mm; p < 0.01). In patients with tumors completely resected, there was no recurrence after either en bloc or piecemeal resection. Six of 8 patients found to have submucosal invasion after endoscopic mucosal resection underwent surgery. Patients with incompletely resected intramucosal lesions underwent additional endoscopic treatment. Cancer recurred in 3 patients (2.8%), all of whom had lesions measuring more than 15 mm in diameter. CONCLUSIONS Endoscopic mucosal resection is safe and useful for the management of early stage gastric cancer. Further improvement in outcome requires more accurate preoperative diagnosis and postoperative histopathologic evaluation. Patients with incompletely resected lesions should undergo aggressive additional treatment.


Oncology | 2003

A Pilot Phase II Study of Capecitabine in Advanced or Recurrent Gastric Cancer

Wasaburo Koizumi; Katsunori Saigenji; Shigeki Ujiie; Masanori Terashima; Yu Sakata; Taguchi T

Objectives: To evaluate the efficacy and safety of capecitabine in patients with advanced or recurrent gastric cancer, we conducted a pilot phase II study in Japan. Methods: Patients with advanced or recurrent gastric cancer were given oral capecitabine 828 mg/m2 twice daily for 3 weeks, followed by 1 week of no treatment. Two or more cycles were administered. From July 1996 to December 1997, 32 patients were enrolled in the study. The response to capecitabine was evaluated in 31 patients, excluding 1 found to be ineligible. Results: The overall response rate was 19.4% (6/31, 95% confidence interval: 7.5–37.5%). The median duration of response was 124.5 days, the median time to disease progression 85.0 days, and the median survival time 247.5 days. Drug-related adverse events of grade 3 or higher were infrequent: in 2 patients (6.3%) total bilirubin concentration increased, and 1 patient (3.1%) each had elevation of GOT, anemia, lymphopenia, increased creatinine, and hand-foot syndrome. No patient had gastrointestinal toxicity of grade 3 or higher. Conclusion: Capecitabine was suggested to be safe and effective in the treatment of advanced or recurrent gastric cancer. Further phase II studies of capecitabine on a large scale are warranted.


Gastrointestinal Endoscopy | 1999

Usefulness of endoscopic aspiration mucosectomy as compared with strip biopsy for the treatment of gastric mucosal cancer

Satoshi Tanabe; Wasaburo Koizumi; Mikio Kokutou; Hiroshi Imaizumi; Keita Ishii; Mitsuhiro Kida; Yasushi Yokoyama; Masahito Ohida; Katsunori Saigenji; Hitoshi Shimao; Hiroyuki Mitomi

BACKGROUND Several techniques are available for the endoscopic treatment of gastric intramucosal cancers, but their advantages and disadvantages have not been adequately evaluated. We compared the therapeutic usefulness of endoscopic aspiration mucosectomy with that of strip biopsy. METHODS Between May 1995 and May 1997, we performed strip biopsy (May 1995 through February 1996) or endoscopic aspiration mucosectomy (March 1996 through May 1997) in a consecutive series of patients with intestinal-type intramucosal cancer. Parameters of assessment included the following: size of removed specimens, en bloc resection rate, time required for resection, duration of hospitalization, and complications. RESULTS Forty-nine patients with gastric intramucosal cancers underwent endoscopic aspiration mucosectomy and 44 underwent strip biopsy. The two groups were similar with respect to age, gender, and lesion macroscopic appearance, size, and site. The mean longest diameter of the resected specimens was significantly greater with endoscopic aspiration mucosectomy (20.3 +/- 3.4 mm) than with strip biopsy (15. 8 +/- 4.4 mm) (p < 0.001). The rate of en bloc resection (resection of an entire lesion in one procedure) was significantly higher with endoscopic aspiration mucosectomy (61.2%, 30 of 49) than with strip biopsy (36.4%, 16 of 44) (p < 0.05). The number of specimens obtained by piecemeal resection was slightly, but not significantly, higher with strip biopsy (2.4 +/- 1.7) than with endoscopic aspiration mucosectomy (2.0 +/- 1.7). The time required for treatment was similar for each procedure. The duration of hospitalization was significantly shorter with endoscopic aspiration mucosectomy (12.8 +/- 5.3 days) than with strip biopsy (15.9 +/- 74 days) (p < 0.05). As for complications, the rate of bleeding was 20. 5% (9 of 44) with strip biopsy and 10.2% (5 of 49) with endoscopic aspiration mucosectomy; bleeding was controlled in all cases by treatment with a heater probe. CONCLUSIONS Endoscopic resection of large gastric intramucosal tumors is easier with endoscopic aspiration mucosectomy compared with strip biopsy. Endoscopic aspiration mucosectomy is a useful procedure for en bloc resection.


Gastric Cancer | 2002

Phase II study of paclitaxel with 3-h infusion in patients with advanced gastric cancer

Kensei Yamaguchi; Masahiro Tada; Horikoshi N; Toru Otani; Hiroya Takiuchi; Soh Saitoh; Ryunosuke Kanamaru; Yasushi Kasai; Wasaburo Koizumi; Yuh Sakata; Taguchi T

Abstract.Abstract.Background: To increase the options for agents for gastric cancer chemotherapy, we performed a phase II clinical trial on the use of a 3-h infusion of paclitaxel to confirm its efficacy and the feasibility of its use in patients with advanced gastric cancer.Methods: Thirty-two (32) patients with measurable metastatic gastric cancer were enrolled in this study. Seventeen patients (53%) had received prior chemotherapy for metastatic disease, 4 patients (13%) had adjuvant chemotherapy alone, and 11 patients (34%) were chemotherapy-naive.Paclitaxel was intravenously infused for 3 h, at a dose of 210 mg/m2, once every 3 weeks. To prevent hypersensitivity reactions, standard premedication was administered to all patients.Results: Nine (28%; 9/32 ) objective partial responses (PRs) were observed (95% confidence interval [CI], 14%–47%), and the remaining 23 patients showed stable (12 patients; 37.5%) and progressive disease (11 patients; 34.4%). The median time to response was 20 days (range, 14–38 days). The median response duration was 87 days (range, 50–103 days). The median survival of all patients was 234 days (range, 13–646+ days). The major adverse reactions were myelosuppression (grade 3/4 leukopenia and neutropenia were observed in 59% and 88% of the patients, respectively), alopecia, and peripheral neuropathy. Peripheral neuropathy was observed in 19 patients, however, most of the patients recovered after the completion of treatment.Conclusion: A 3-h infusion of paclitaxel is an effective therapy for advanced gastric cancer and is clinically well tolerated by the patients.


British Journal of Cancer | 2012

Phase I study of TAS-102 treatment in Japanese patients with advanced solid tumours

Toshihiko Doi; Atsushi Ohtsu; Takayuki Yoshino; Narikazu Boku; Y Onozawa; Akira Fukutomi; Shuichi Hironaka; Wasaburo Koizumi; T Sasaki

Background:TAS-102 consists of α, α, α-trifluorothymidine (TFT) and an inhibitor of thymidine phosphorylase (TPI). We conducted a dose-escalation phase I study in Japanese patients with advanced solid tumours.Methods:TAS-102 was administered twice daily on days 1–5 and days 8–12 in a 28-day cycle to patients with solid tumours refractory to standard chemotherapy, to determine its maximum tolerated dose (MTD), dose-limiting toxicities (DLTs), and pharmacokinetics (PKs). MTD was evaluated in cycle 1.Results:Safety and PKs were evaluated in 21 patients treated with TAS-102 at 30, 40, 50, 60, or 70 mg m−2 per day. DLTs, such as grade 4 leucopenia, grade 4 neutropenia, and grade 4 thrombocytopenia, were observed in two patients at doses of 30 and 70 mg m−2. α, α, α-trifluorothymidine and TPI exposures increased dose dependently, and the percentage of decrease in neutrophil count and TFT exposure were significantly correlated. The disease control rate was 50.0% with a median progression-free survival of 2.4 months in 18 colorectal cancer patients. The dose of TAS-102 was not increased above 70 mg m−2 per day because of the increased tendency for grade 3 and 4 neutropenia, and 70 mg m−2 per day was the recommended dose for phase II studies.Conclusions:TAS-102 at 70 mg m−2 per day was tolerated in Japanese patients with advanced solid tumours. Phase II studies are ongoing in patients with colorectal cancer.

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