Manabu Arai
Chiba University
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Publication
Featured researches published by Manabu Arai.
European Journal of Cancer | 2009
Rikiya Nakamura; Masahiro Sakakibara; Takeshi Nagashima; Takafumi Sangai; Manabu Arai; Toshihiko Fujimori; Shigetsugu Takano; Takashi Shida; Yukio Nakatani; Masaru Miyazaki
It has been revealed that sentinel lymph nodes (SLNs) from patients with node-negative breast cancer involve RT-PCR detected micrometastases and isolated tumour cells. However, the prognostic significance of the pathologically undetectable micrometastases is still controversial. In this study, we evaluated Foxp3 positive regulatory T cells (Treg) in SLNs as host-side immune marker that has the potential to detect these micrometastases. In the analyses of training set (n=30), elevated Treg was strongly associated with the pathologically undetectable micrometastases. In the analyses of validation set (n=129) in patients with node-negative, relapse-free survival in patients with elevated Treg was significantly shorter than those with lower Treg (p=0.005). Furthermore, in multivariate analyses, elevated Treg was correlated with relapse-free survival (p=0.012). Our data indicate that Treg may increase in the microenvironment of SLNs along with pathologically undetectable micrometastases and is a prognostic predictor in patients with node-negative breast cancer.
Journal of The American College of Surgeons | 2008
Masahiro Sakakibara; Takeshi Nagashima; Takafumi Sangai; Rikiya Nakamura; Hiroshi Fujimoto; Manabu Arai; Toshiki Kazama; Hideyuki Hashimoto; Yukio Nakatani; Masaru Miyazaki
BACKGROUND In this study, we report a breast-conserving surgery (BCS) approach that uses projection and reproduction techniques of breast MRI obtained in the surgical position to the breast surface in patients with ductal carcinoma in situ (DCIS) of the breast. STUDY DESIGN Between February 2005 and January 2007, a total of 104 patients with operable breast cancer at our hospital had surgical-position breast MRI examinations. The 24 patients with relatively localized DCIS received BCS using the projection and reproduction techniques of the surgical-position breast MRI. During the same time period, 28 patients with relatively localized DCIS in whom prone-position breast MRI was performed, had conventional BCS using mammography-guided hookwires. In this study, we compared the surgical outcomes of our surgical approach with those of the conventional approach in a total of 52 patients with relatively localized DCIS. RESULTS Average volume of the pathologic specimens in the new technique group (27.5 cm(3)) was substantially smaller than that in the conventional BCS group (57.6 cm(3), p = 0.0007). In addition, the positive margin rate was substantially lower in the new technique group (12.5%) than in the conventional BCS group (39.3%; p = 0.029). CONCLUSIONS This study demonstrates that BCS can be done guided by the precise projection and reproduction techniques of the lesion obtained by surgical-position breast MRI. To the best of our knowledge, this is the first report of BCS technique for DCIS in this manner. Our surgical approach can be clinically useful in surgical planning and management in patients with DCIS.
Clinical Imaging | 2007
Takeshi Nagashima; Masahiro Sakakibara; Rikiya Nakamura; Manabu Arai; Masami Kadowaki; Toshiki Kazama; Yukio Nakatani; Keiji Koda; Masaru Miyazaki
BACKGROUND Primary chemotherapy for breast cancer is effective as postoperative adjuvant therapy. However, one of the critical disadvantages was a treatment delay for patients with progressive disease. The present study attempts to clarify quantitative parameters on MRI which can be used to predict the sensitivity to treatment in breast cancer patients. METHODS The subjects consisted of 26 patients with invasive ductal breast cancer who received primary chemotherapy before surgery. The mean maximum tumor dimension was 3.3cm, and 21 cases had nodal involvements. Three cases demonstrated histological grade 3. Dynamic enhanced MRI was evaluated at three different time periods; prior to, in the midst of preoperative chemotherapy, and just before the initial operation. The signal intensity ratio (SIR) and early contrast uptake (ECU) were calculated, as well as the correlation between these dynamic data and the tumor reduction rates were analyzed retrospectively. P-values of less than 0.05 were considered to indicate statistically significant. RESULTS Responders to chemotherapy had the significantly higher SIR and ECU values than non-responders (p=0.0454 and 0.0334, respectively). ECU value significantly decreased as tumor reduction by chemotherapy (p=0.0028). Pathological tumor dimension was significantly correlated with the tumor size estimated on presurgical MRI (p<0.0001). CONCLUSIONS Our current series demonstrated the significant correlation between pretreatment MRI data and tumor reduction by chemotherapy in breast cancer patients. With these results, it seems possible to define good and non-responders prior to treatment.
Breast Cancer | 2011
Naohito Yamamoto; Hiroshi Fujimoto; Rikiya Nakamura; Manabu Arai; Atsushi Yoshii; Sachiko Kaji; Makiko Itami
Breast Cancer | 2007
Rikiya Nakamura; Takeshi Nagashima; Masahiro Sakakibara; Shigeharu Nakano; Naoto Tanabe; Hiroshi Fujimoto; Manabu Arai; Masami Kadowaki; Takashi Oide; Toru Tanizawa; Masaru Miyazaki
The Breast | 2008
Rikiya Nakamura; Takeshi Nagashima; Masahiro Sakakibara; Takafumi Sangai; Hiroshi Fujimoto; Manabu Arai; Takashi Shida; Katsuhiko Kaneoya; Takuya Ueda; Yukio Nakatani; Hideyuki Hashimoto; Masaru Miyazaki
Breast Cancer | 2007
Masami Kadowaki; Takeshi Nagashima; Hiroto Sakata; Masahiro Sakakibara; Takafumi Sangai; Rikiya Nakamura; Hiroshi Fujimoto; Manabu Arai; Yasuhide Onai; Yuichirou Nagai; Yukimasa Miyazawa; Masaru Miyazaki
Nihon Rinsho Geka Gakkai Zasshi (journal of Japan Surgical Association) | 2011
Junta Sakakibara; Naohito Yamamoto; Rikiya Nakamura; Manabu Arai; Yohsuke Ohki; Masaru Miyazaki
Nihon Rinsho Geka Gakkai Zasshi (journal of Japan Surgical Association) | 2009
Nobumitsu Shiina; Manabu Arai; Takafumi Sangai; Masahiro Sakakibara; Takeshi Nagashima; Masaru Miyazaki
Ultrasound in Medicine and Biology | 2006
Takeshi Nagashima; Masahiro Sakakibara; Rikiya Nakamura; Masami Kadowaki; Manabu Arai; Masaru Miyazaki