Nobuyuki Shigaki

Publications (2)2.63 Total impact

• Article: Chemotherapy with bevacizumab for metastatic colorectal cancer: a retrospective review of 181 Japanese patients.

  Seiya Saito, Naoko Hayashi, Nobutaka Sato, Masaaki Iwatsuki, Yoshifumi Baba, Yasuo Sakamoto, Yuji Miyamoto, Masayuki Watanabe, Minoru Yoshida, Kenji Sakai, Takashi Katsumori, Shigeru Katahuchi, Nobuyuki Shigaki, Kazutaka Yamada, Masami Kimura, Tomio Tanigawa, Sadamu Takano, Masafumi Kuramoto, Hideo Baba
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  ABSTRACT: BACKGROUND: There has so far been little information on the clinical effect of bevacizumab against colorectal cancer in Japan. Hence, this study was conducted to retrospectively evaluate the safety and efficacy of bevacizumab in clinical practice. METHODS: A total of 181 patients with metastatic colorectal cancer (mCRC) received bevacizumab in combination with chemotherapy at 18 hospitals in Kumamoto prefecture, Japan. We surveyed the medical records of all patients regarding the patient characteristics, objective tumor responses, and adverse events. We analyzed their overall survival and the survival benefit when continuing the administration of bevacizumab beyond disease progression (progressive disease; PD) in patients who received bevacizumab-containing 1st line therapy. RESULTS: The response rate (RR) in all lines of therapy was 42 %. The 1st line patients showed significantly better survival in comparison to the patients who received further lines of treatment (P = 0.005). There were no significant differences in survival between the group with post-PD treatment with bevacizumab and the group with post-PD treatment without bevacizumab (P = 0.13). The most common grade 3 or greater adverse event associated with bevacizumab was hypertension (12.2 %). Especially, a high incidence of gastrointestinal (GI) perforation was shown in this study (4.4 %) and most of the patients with GI perforation had some risk factors for this complication. CONCLUSION: Although the survival benefit of bevacizumab in Japanese patients with mCRC was similar to that observed in previous clinical trials, this study showed a high incidence of GI perforation in comparison to previous studies. Therefore, the careful selection of patients with few risk factors for this complication is likely to lead to a greater benefit from bevacizumab treatment.
  International Journal of Clinical Oncology 06/2012; · 1.41 Impact Factor
• Article: Reduction of estrogen and prolactin receptors in 7,12-dimethylbenz(a)anthracene-induced rat mammary tumor by high doses of estrogen

  Nobuyuki Shigaki, Masaharu Kimura, Sadamu Takano, Noboru Fujino, Masanobu Akagi
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  ABSTRACT: Daily injections of 100 μg17 β-estradiol, or 250 μg tamoxifen, for 10 days led to a regression of the 7,12-dimenthylbenz(a)anthracene (DMBA)-induced rat mammary tumor. Estrogen receptor (ER), progesterone receptor (PgR), and prolactin receptor (PRL-R) in the regressed tumor were significantly reduced in the estrogen-treated rats. ER and PRL-R were low but PgR increased significantly in the tumor of the tamoxifen-treated rats. A single administration of 100 μg estradiol induced a transient decrease of ER and PRL-R, and an increase of PgR, in the DMBA-tumor. Similar decreases in ER and PRL-R and the increase of PgR were observed 8 hours after the 5th injection of 100 μg estradiol—a time when the tumor had already regressed. These results suggest that high dose-estrogen has a direct inhibitory effect on the concentration of both ER and PRL-R in the DMBA-tumor, and that this effect might be accumulative with repeated administrations. It is unlikely that the inhibition of the estrogenic effect caused by loss of ER is the sole mechanism of the regression of the DMBA-tumor, since the increased synthesis of PgR as a marker of estrogen action was observed even after the ER-reduction and tumor-regression.
  Surgery Today 04/1987; 17(5):395-401. · 1.22 Impact Factor