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Dive into the research topics where Masatsugu Ishii is active.

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Featured researches published by Masatsugu Ishii.


Digestive Surgery | 2014

Oncological impact of laparoscopic lymphadenectomy with preservation of the left colic artery for advanced sigmoid and rectosigmoid colon cancer.

Masashi Yamamoto; Junji Okuda; Keitaro Tanaka; Masatsugu Ishii; Hiroki Hamamoto; Kazuhisa Uchiyama

Background: Laparoscopic lymphadenectomy around the inferior mesenteric artery (IMA) with preservation of the left colic artery (LCA) remains a controversial approach. The aim of the study was to investigate the clinical outcomes. Methods: This study analysed 211 patients who underwent laparoscopic resection of advanced (≥T3) sigmoid and rectosigmoid colon cancers with D3 lymphadenectomy including 91 high ligations of the IMA (HL) and 120 low ligations with preservation of the LCA (LL) from January 1998 to December 2009. Results: There were no significant differences in operative result between the groups. In stage II cancer, the overall survival rate (94.8% HL vs. 91.8% LL; 95% confidence interval (CI), -0.8 to 0.68, p = 0.920) and disease-free survival (93.0% HL vs. 87.6% LL; 95% CI, -0.8 to 0.40, p = 0.540) did not differ significantly between the two groups. A similar tendency in overall survival was observed in patients with stage III cancer (88.3% HL vs. 86.9% LL; 95% CI, -0.44 to 0.57, p = 0.989) and disease-free survival (71.4% HL vs. 69.8% LL; 95% CI, -0.38 to 0.40, p = 0.637). Conclusions: Laparoscopic lymphadenectomy around the IMA with preservation of the LCA resulted in acceptable clinical outcomes in patients with advanced sigmoid and rectosigmoid colon cancer.


Scientific Reports | 2016

Prediction of postoperative liver regeneration from clinical information using a data-led mathematical model

Kimiyo N. Yamamoto; Masatsugu Ishii; Yoshihiro Inoue; Fumitoshi Hirokawa; Ben D. MacArthur; Akira Nakamura; Hiroshi Haeno; Kazuhisa Uchiyama

Although the capacity of the liver to recover its size after resection has enabled extensive liver resection, post-hepatectomy liver failure remains one of the most lethal complications of liver resection. Therefore, it is clinically important to discover reliable predictive factors after resection. In this study, we established a novel mathematical framework which described post-hepatectomy liver regeneration in each patient by incorporating quantitative clinical data. Using the model fitting to the liver volumes in series of computed tomography of 123 patients, we estimated liver regeneration rates. From the estimation, we found patients were divided into two groups: i) patients restored the liver to its original size (Group 1, n = 99); and ii) patients experienced a significant reduction in size (Group 2, n = 24). From discriminant analysis in 103 patients with full clinical variables, the prognosis of patients in terms of liver recovery was successfully predicted in 85–90% of patients. We further validated the accuracy of our model prediction using a validation cohort (prediction = 84–87%, n = 39). Our interdisciplinary approach provides qualitative and quantitative insights into the dynamics of liver regeneration. A key strength is to provide better prediction in patients who had been judged as acceptable for resection by current pragmatic criteria.


World Journal of Surgery | 2018

Preoperative Chemotherapy May Not Influence the Remnant Liver Regenerations and Outcomes After Hepatectomy for Colorectal Liver Metastasis

Yoshihiro Inoue; Kensuke Fujii; Keitaro Tashiro; Masatsugu Ishii; Shinsuke Masubuchi; Masashi Yamamoto; Tetsunosuke Shimizu; Mitsuhiro Asakuma; Fumitoshi Hirokawa; Michihiro Hayashi; Yoshihumi Narumi; Kazuhisa Uchiyama

BackgroundVarious chemotherapy regimens have been shown to improve outcomes when administered before tumor excision surgery. However, there is no consensus on the utility of multidisciplinary treatment with preoperative chemotherapy for treating colorectal liver metastasis (CLM).Materials and methodsTwo hundred-fifty patients who underwent hepatectomy were retrospectively analyzed using propensity score matching. Postoperative outcomes were evaluated with a focus on the effect of pre-hepatectomy chemotherapy on regeneration of the remnant liver in patients with CLM. The remnant liver volumes (RLVs) were postoperatively measured with multidetector computed tomography on days 7 and months 1, 2, 5, and 12 after the operation.ResultsRLV regeneration and blood test results did not significantly differ between patients who underwent preoperative chemotherapy versus those who did not immediately after surgery or at any time point from postoperative day 7 to postoperative month 12. The 1-, 2-, and 3-year overall survival (OS) rates for all patients were 94.6, 86.2, and 79.9%, respectively; the corresponding disease-free survival (RFS) rates were 49.3, 38.6, and 33.7%, respectively. There were no significant differences in OS and RFS between the two groups after hepatic resection. The recurrence rates, including marginal and intrahepatic recurrences, as well as resection frequency of the remnant liver were not significantly different between the two groups.ConclusionPreoperative chemotherapy may have no appreciable benefit for patients with CLM in terms of perioperative and long-term outcomes.


Wspolczesna Onkologia-Contemporary Oncology | 2018

The utility of the subcuticular suture in hepatic resection

Yoshihiro Inoue; Kensuke Fujii; Masatsugu Ishii; Syuji Kagota; Hiroki Hamamoto; Wataru Osumi; Yusuke Tsuchimoto; Shinsuke Masubuchi; Masashi Yamamoto; Akira Asai; Koji Komeda; Shinya Fukunishi; Fumitoshi Hirokawa; Kazuhide Higuchi; Kazuhisa Uchiyama

Aim of the study Despite recent technical progress and advances in the perioperative management of liver surgery, postoperative surgical site infection (SSI) is still one of the most common complications that extends hospital stays and increases medical expenses following hepatic surgery. Material and methods From 2001 to 2017 a total of 1180 patients who underwent hepatic resection for liver tumours were retrospectively analysed with respect to the predictive factor of superficial incisional SSI, using a propensity score matching by procedure (subcuticular or mattress suture). Results The incidence of superficial and deep incisional SSIs was found to be 7.1% (84/1180). By propensity score matching (PSM), 121 of the 577 subcuticular suture group patients could be matched with 121 of the 603 mattress suture group patients. Multivariate analysis demonstrated wound closure technique as the only independent risk factor that correlated significantly with the occurrence of superficial incisional SSIs (p = 0.038). C-reactive protein (CRP) levels on postoperative day 4 were significantly higher in patients with incisional SSIs than in those without (p < 0.001). Conclusions Wound closure technique with subcuticular continuous spiral suture using absorbable suture should be considered to minimise the incidence of incisional SSIs. Moreover, wounds should be carefully checked when CRP levels are high on postoperative day 4.


Videosurgery and Other Miniinvasive Techniques | 2018

Comparison of resection site of standardized laparoscopic hepatic tumor resection

Yoshihiro Inoue; Masatsugu Ishii; Yusuke Tsuchimoto; Shinsuke Masubuchi; Masashi Yamamoto; Akira Asai; Shinya Fukunishi; Fumitoshi Hirokawa; Kazuhide Higuchi; Kazuhisa Uchiyama

Introduction The degree of difficulty in laparoscopic hepatic resection (LHR) was higher in tumors involving the suprahepatic segments than other sites. However, thanks to surgical instruments and procedures being improved and standardized, LHR can be performed safely in all regions. Aim We report our standardized surgical techniques and outcomes in a series of patients undergoing LHR in our hospital and analyze the surgical outcomes, particularly with regard to the site of resection. Material and methods We retrospectively analyzed data from 238 patients who underwent standardized laparoscopic partial hepatic resection between 2010 and 2017. In standardized LHR, the operator formed a triangle with the laparoscope in the center, maintaining a co-axial position by changing the port where the laparoscope was inserted. Results Operative time for the resection of tumors of the right hepatic lobe was 202 ±92 min and 140 ±104 min for tumors of the left hepatic lobe (p = 0.0024); intraoperative blood loss was 80 ±170 ml and 19 ±127 ml, respectively (p = 0.0016). No differences were found in the surgical outcomes between the various segments of the right hepatic lobe. In the left hepatic lobe, operative time was significantly shorter with laparoscopic tumor resection in segment III (p = 0.0023). Conclusions During standardized LHR, a better field of vision with the greater ease can be established during resection of the left hepatic lobe compared to that of the right hepatic lobe. Nonetheless, LHR of the right lobe can be performed safely using various surgical instruments and techniques.


Journal of Medical Case Reports | 2018

Intestinal endometriosis combined with colorectal cancer: a case series

Masatsugu Ishii; Masashi Yamamoto; Keitaro Tanaka; Mitsuhiro Asakuma; Shinsuke Masubuchi; Hiroki Hamamoto; Hiroshi Akutagawa; Yutaro Egashira; Yoshinobu Hirose; Junji Okuda; Kazuhisa Uchiyama

BackgroundIntestinal endometriosis is a common benign disease among menstruating women that affects the intestinal tract.Case presentationThis case report presents seven Japanese cases of intestinal endometriosis with colorectal cancer treated by laparoscopic surgery. Five of the seven cases reported here are women presenting with bowel obstruction due to colorectal endometriosis with colorectal cancer. It can be confused with serious lesions such as advanced colorectal cancer with peritoneal involvement or invasion of adjacent organs (T4).ConclusionsTherefore, we should consider the probability that the cause of bowel obstruction is not T4 but intestinal endometriosis. For surgical treatment, we recommend laparoscopic surgery for colorectal resection because of its benefits of differential diagnosis of T4, preserving fertility, and preventing excessive surgical stress. We performed laparoscopic resection in seven patients with intestinal endometriosis and colorectal cancer. These cases demonstrate the difficulty of establishing a differential diagnosis of intestinal endometriosis with colorectal cancer from T4.


Journal of Gastrointestinal Surgery | 2018

The Relationship Between Postoperative Chemotherapy and Remnant Liver Regeneration and Outcomes After Hepatectomy for Colorectal Liver Metastasis

Yoshihiro Inoue; Kensuke Fujii; Masatsugu Ishii; Syuji Kagota; Hiroki Hamamoto; Wataru Osumi; Tetsuji Terasawa; Yusuke Tsuchimoto; Shinsuke Masubuchi; Masashi Yamamoto; Akira Asai; Koji Komeda; Shinya Fukunishi; Fumitoshi Hirokawa; Masahiro Goto; Yoshihumi Narumi; Kazuhide Higuchi; Kazuhisa Uchiyama

BackgroundPostoperative chemotherapy for treating colorectal liver metastasis (CLM) has been introduced with the aim of improving therapeutic outcomes. However, there is no consensus on the utility of multidisciplinary treatments with postoperative chemotherapy. Therefore, we evaluated surgical outcomes in patients with CLMs who underwent hepatectomy, while focusing on the effects of post-hepatectomy chemotherapy on remnant liver regeneration.MethodsTwo hundred ninety patients who underwent hepatectomy were retrospectively analyzed using propensity score matching. Postoperative outcomes were evaluated with a focus on the effects of post-hepatectomy chemotherapy on regeneration of the remnant liver in patients with CLM. The remnant liver volumes (RLVs) were measured postoperatively using multi-detector computed tomography on day 7 and months 1, 2, 5, and 12 after the operation.ResultsRLV regeneration and postoperative blood laboratory data did not differ significantly between patients who received postoperative chemotherapy and those who did not receive postoperative chemotherapy immediately after surgery or at any time point from postoperative day 7 to postoperative month 12. The recurrence rates, including same and other segmental intrahepatic recurrences, as well as the resection frequency of the remnant liver were not significantly different between the two groups.ConclusionPostoperative chemotherapy may be of small significance for patients with CLM in terms of the remnant liver volume regeneration and functional recovery.


Digestive Surgery | 2018

Surgical Outcome and Hepatic Regeneration after Hepatic Resection for Hepatocellular Carcinoma in Elderly Patients

Yoshihiro Inoue; Ryo Tanaka; Kensuke Fujii; Nao Kawaguchi; Masatsugu Ishii; Shinsuke Masubuchi; Masashi Yamamoto; Fumitoshi Hirokawa; Michihiro Hayashi; Kazuhisa Uchiyama

Introduction: The rising proportion of elderly patients (aged 80 yearsor above) in our population means that more elderly patients are undergoing hepatectomy. Methods: Five-hundred and thirty patients who underwent hepatectomy for hepatocellular carcinoma (HCC) were retrospectively analyzed with respect to their preoperative status and perioperative results, including remnant liver regeneration. The remnant liver volume was postoperatively measured with multidetector CT on postoperative day 7 and 1, 2, 5, and 12 months after surgery. An elderly group (aged 80 or older) was compared with a non-elderly group (aged less than 80 years). Results: Underlying diseases of the cardiovascular system were significantly more common in the elderly group (57.8%, p = 0.0008). The postoperative incidence of Clavien-Dindo Grade IIIa or higher complications was 20.0% in the elderly group and 24.3% in the non-elderly group, and this difference was not significant. As for regeneration of the remnant liver after resection, this was not morphologically delayed compared to the non-elderly group. Conclusions: In this study, we have demonstrated that safe, radical hepatectomy, similar to procedures performed on non-elderly patients, can be performed on patients with HCC aged 80 and older with sufficient perioperative care.


American Journal of Surgery | 2018

Risk factors for surgical site infection after stoma closure comparison between pursestring wound closure and conventional linear wound closure: Propensity score matching analysis

Masashi Yamamoto; Keitaro Tanaka; Shinsuke Masubuchi; Masatsugu Ishii; Hiroki Hamamoto; Shigenori Suzuki; Yasuhiko Ueda; Junji Okuda; Kazuhisa Uchiyama


Journal of Gastrointestinal Surgery | 2017

Laparoscopic Liver Resection Using the Lateral Approach from Intercostal Ports in Segments VI, VII, and VIII

Yoshihiro Inoue; Yusuke Suzuki; Kensuke Fujii; Nao Kawaguchi; Masatsugu Ishii; Shinsuke Masubuchi; Masashi Yamamoto; Fumitoshi Hirokawa; Michihiro Hayashi; Kazuhisa Uchiyama

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Kazuhisa Uchiyama

Wakayama Medical University

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