Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Osamu Muto.
Japanese Journal of Clinical Oncology | 2008
Kohei Shitara; Munakata M; Osamu Muto; Yuh Sakata
A 61-year-old female with surgically treated rectal cancer that had metastasized to lung and lymph nodes was treated with bevacizumab (BV) plus 5-fluorouracil (5-FU) and leucovorin (LV) as third-line chemotherapy after treatment failures with infusional 5-FU, LV and oxaliplatin (FOLFOX regimen); and infusional 5-FU, LV and irinotecan (FOLFIRI regimen). After four cycles of treatment, a computed tomography scan revealed reduced sizes of the lung and lymph node metastases. Tumor response has still been maintained after six cycles of treatment, and the chemotherapeutic response was evaluated as partial response according to the Response Evaluation Criteria In Solid Tumor guidelines. Manageable toxicity included grade 2 hypertension, grade 1 epistaxis and grade 1 stomatitis. Although there are no clinical trial results supporting the use of BV-containing therapy as third-line chemotherapy for advanced colorectal cancer, BV plus 5-FU and LV was effective and feasible in our patient with colon cancer that had progressed after treatment with 5-FU, irinotecan and oxaliplatin.
Oncology | 2008
Kohei Shitara; Yoshito Komatsu; Satoshi Yuki; Munakata M; Osamu Muto; Sen Shimaya; Yuh Sakata
Objective: The aim of this study was to evaluate the efficacy and safety of a combination regimen using irinotecan plus S-1 in patients with metastatic pancreatic cancer. Methods: Based on the results of our previous phase I/II study in patients with gastric and colorectal cancer, we initiated a regimen with irinotecan at 100 mg/m2 on days 1 and 15 and S-1 at 80 mg/m2 starting at day 1 for 14 consecutive days, followed by a 14-day rest period. This treatment was repeated every 28 days. Results: From November 2003 to December 2006, a total of 16 patients were enrolled. All patients presented with metastatic disease. Six patients had received prior gemcitabine. The median number of treatment cycles was 4 (range 1–16) and the response rate was 43.7% (95% confidence interval 19.5–68.1). The median time to progression was 4.9 months, and the median survival time was 11.3 months. Grade 3–4 neutropenia developed in 5 of 16 patients and grade 3 diarrhea in 1 patient. Conclusions: The combination of irinotecan and S-1 is feasible and promising for pancreatic cancer. Further evaluation of this combination chemotherapy is required.
Japanese Journal of Clinical Oncology | 2010
Isamu Okamoto; Munakata M; Masaki Miyazaki; Taroh Satoh; Takenori Takahata; Yasushi Takamatsu; Osamu Muto; Kazuhiko Koike; Kunihiko Ishitani; Taketo Mukaiyama; Yuh Sakata; Kazuhiko Nakagawa; Kazuo Tamura
OBJECTIVEnHormonal imbalance characterized by excessive production of growth hormone (GH) and a low circulating concentration of insulin-like growth factor (IGF)-1 has been demonstrated in individuals with various serious conditions. However, little is known about changes in the GH-IGF-1 axis in cancer patients.nnnMETHODSnWe prospectively examined the circulating levels of several hormones in 58 patients with solid tumors who were classified according to Eastern Cooperative Oncology Group performance status (PS): PS 0-1, n = 15; PS 2, n = 15; PS 3, n = 15; and PS 4, n = 13. The relations of hormone concentrations, with a focus on the GH-IGF-1 system, to PS were evaluated by Spearmans rank correlation test and regression analysis.nnnRESULTSnThe circulating levels of IGF-1, IGF-binding protein-3 and thyroid hormones (total T(3) and T(4)) were inversely correlated with PS score. The concentration of GH was increased irrespective of PS but not statistically significant. The ratio of IGF-I to GH was inversely correlated with PS. The levels of GH and IGF-1 in all patients were also inversely correlated.nnnCONCLUSIONSnThe present study suggests that the GH-IGF-1 axis is disturbed in patients with cancer.
Oncology | 2008
Kohei Shitara; Munakata M; Masaharu Kasai; Osamu Muto; Yuh Sakata
Background: The prognosis of advanced gastrointestinal cancer, especially in patients with poor performance status (PS), is generally dismal. Patients with PS 3–4 are almost ineligible for participation in clinical studies. Patients and Methods: From June 2000 to February 2007, 116 patients with poor PS (PS 3 = 73 and PS 4 = 43) were treated with chemotherapy. Retrospective analysis was performed. Results: Of the 107 patients with at least one measurable lesion, a partial response was obtained in 15 patients (14.0%). Of 65 patients with ascites and/or pleural effusion, 12 patients achieved decreased fluid accumulation. A decline in tumor markers was observed in 30 patients. As a result, 38 patients (32.7%) achieved tumor response, a decrease in fluid accumulation or a decline in tumor markers (responders), which resulted in a survival benefit compared to the other 78 patients without effect (6.9 vs. 2.2 months, p < 0.001). PS improvement was seen in 16 patients (13.8%). Conclusions: The results suggest that chemotherapy may be beneficial in gastrointestinal cancer patients with poor PS, as demonstrated by a certain degree of improvement in PS and survival in responders. Further study is required to confirm the benefit of chemotherapy in this patient population.
Japanese Journal of Clinical Oncology | 2010
Osamu Muto; Munakata M; Chikara Iino; Yuh Sakata
A 42-year-old man was found to have an adenocarcinoma arising from ectopic gastric mucosa in Meckels diverticulum, as diagnosed with surgical pathology. Recurrence was recognized with massive ascites at 1 year and 6 months after surgery. Chemotherapy in the first and second lines was not effective. In the third line of chemotherapy, pemetrexed and carboplatin were both administered and this resulted in a good response for massive ascites. This palliative therapy was effective and safe.
Gan to kagaku ryoho. Cancer & chemotherapy | 2006
Kohei Shitara; Munakata M; Kudo T; Kasai M; Osamu Muto; Okada R; Mitobe S; Ishiguro A; Sakuraba H; Ikami I; Yuh Sakata
Japanese Journal of Clinical Oncology | 2007
Kohei Shitara; Munakata M; Osamu Muto; Ristuko Okada; Sumako Mitobe; Masanari Mino; Isao Ikami; Yuh Sakata
Gan to kagaku ryoho. Cancer & chemotherapy | 2008
Kohei Shitara; Nakamura K; Kasai M; Munakata M; Osamu Muto; Kazaana K; Yuh Sakata
Gan to kagaku ryoho. Cancer & chemotherapy | 2009
Osamu Muto; Munakata M; Kohei Shitara; Sasaki S; Shimaya S; Sato K; Kasai M; Wada R; Kawamura S; Yuh Sakata
Gan to kagaku ryoho. Cancer & chemotherapy | 2007
Kohei Shitara; Munakata M; Osamu Muto; Kasai M; Okada R; Mitobe S; Yuh Sakata