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Dive into the research topics where Hiroya Kuroyanagi is active.

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Featured researches published by Hiroya Kuroyanagi.


Surgery | 2009

Factors affecting the difficulty of laparoscopic total mesorectal excision with double stapling technique anastomosis for low rectal cancer

Takashi Akiyoshi; Hiroya Kuroyanagi; Masatoshi Oya; Tsuyoshi Konishi; Meiki Fukuda; Yoshiya Fujimoto; Masashi Ueno; Satoshi Miyata; Toshiharu Yamaguchi

BACKGROUND Although the laparoscopic approach is accepted for the treatment of colon cancer, its value for low rectal cancer is unknown. The purpose of this study was to evaluate the influence of patient and tumor factors, particularly pelvic dimensions, on the difficulties in laparoscopic total mesorectal excision (TME) for low rectal cancer. METHODS Seventy-nine consecutive patients underwent laparoscopic TME with intracorporeal rectal transection and double stapling technique (DST) anastomosis for low rectal cancer. Gender, body mass index (BMI), tumor diameter, tumor depth, tumor distance from the anal verge, preoperative chemoradiotherapy, and 5 pelvic dimensions (pelvic inlet, pelvic outlet, length of sacrum, interspinous distance, and intertuberous distance) were analyzed as variables affecting the difficulties of laparoscopic TME. The dependent variables were pelvic operative time, which was defined as the time required for dissection of the rectum from the pelvis, intracorporeal transaction, and anastomosis. Other dependent variables were intraoperative blood loss, overall postoperative morbidity, and anastomotic leakage. Univariate and multivariate analyses were performed to determine the predictive significance of variables. RESULTS Multivariate analysis showed that BMI (P < .0001), tumor distance from the anal verge (P = .0003), tumor depth (P = .0021), and pelvic outlet (P = .0362) were independently predictive of pelvic operative time. Pelvic operative time was related to intraoperative blood loss (P < .0001). The tumor distance from the anal verge (P = .0333, odds ratio [OR]: 1.06) was related to postoperative morbidity, and pelvic outlet was related to anastomotic leakage (P = .0305, OR: 1.13). CONCLUSION BMI, tumor distance from the anal verge, tumor depth, and pelvic outlet were independent predictors for operative time and morbidity. These factors should be taken into account when planning laparoscopic TME.


American Journal of Surgery | 2011

Incidence of and risk factors for anastomotic leakage after laparoscopic anterior resection with intracorporeal rectal transection and double-stapling technique anastomosis for rectal cancer

Takashi Akiyoshi; Masashi Ueno; Yosuke Fukunaga; Satoshi Nagayama; Yoshiya Fujimoto; Tsuyoshi Konishi; Hiroya Kuroyanagi; Toshiharu Yamaguchi

BACKGROUND Laparoscopic rectal cancer surgery involving rectal division with intracorporeal stapling devices is technically difficult. This study aimed to identify risk factors for anastomotic leakage associated with laparoscopic anterior resection for rectal cancer. METHODS We studied 363 patients who underwent laparoscopic anterior resection with intracorporeal rectal transection and double-stapling technique (DST) anastomosis for rectal cancer between July 2005 and February 2010. Twenty-two independent clinical variables were examined by univariate and multivariate analyses. The outcome of interest was clinical anastomotic leakage. RESULTS Anastomotic leakage was identified in 13 (3.6%) patients. Multivariate analysis identified middle/lower rectal cancer (odds ratio, 9.446) and lack of pelvic drain (odds ratio, 3.814) as independent predictive factors for anastomotic leakage. The number of cartridges used for rectal division had no significant impact on anastomotic leakage. CONCLUSIONS Laparoscopic anterior resection involving intracorporeal rectal transection and DST anastomosis is safe if performed using an appropriate technique.


Surgical Endoscopy and Other Interventional Techniques | 2008

Standardized technique of laparoscopic intracorporeal rectal transection and anastomosis for low anterior resection.

Hiroya Kuroyanagi; Masatoshi Oya; Masashi Ueno; Yoshiya Fujimoto; Toshiharu Yamaguchi; Tetsuichiro Muto

BackgroundRectal transection and anastomosis at the lower rectum is the most challenging part of laparoscopic low anterior resection. Therefore, some have demonstrated that rectal transection should be performed using instruments for open surgery with small laparotomy. In our institute, however, rectal transection using a currently available endostapler followed by anastomosis with a double stapling technique is usually performed.MethodsThe important points of our technique are as follows: trocar placement, optimal device choice, harmonious movement between the operator and assistant for rectal transection, optimal point of piercing with the center rod of the circular stapler, and ideal positioning of the proximal colon.ResultsSeventy-eight patients underwent low anterior resection using this technique. There were no conversions to open surgery. All rectal transections were completed laparoscopically with an available endostapler. A diverting ileostomy was created in six cases. Anastomotic leakage occurred in only two patients (2.6%) and rectovaginal fistula in only one patient (1.3%).ConclusionsOur standardized technique is considered to be safe and feasible for rectal transection and anastomosis using the double stapling technique (DST).


Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2011

Effect of body mass index on short-term outcomes of patients undergoing laparoscopic resection for colorectal cancer: a single institution experience in Japan.

Takashi Akiyoshi; Masashi Ueno; Yosuke Fukunaga; Satoshi Nagayama; Yoshiya Fujimoto; Tsuyoshi Konishi; Hiroya Kuroyanagi; Toshiharu Yamaguchi

Background: The impact of body mass index (BMI) on laparoscopic surgery for colorectal cancer in Asian countries is unclear, partly because obesity is less common in Asia than in western countries. The purpose of this study was to evaluate the association between BMI and short-term outcomes after laparoscopic resection for colorectal cancer in Japanese patients. Methods: A cohort of 1194 patients who underwent laparoscopic resection for colorectal cancer at Cancer Institute Hospital between July 2005 and February 2010 were enrolled in this prospective study. Outcomes were analyzed according to BMI category: nonobese (BMI<25), obese I (25⩽BMI<30), and obese II (BMI≥30). Results: A total of 926 patients (78%) were classified as nonobese, 243 (20%) were obese I, and 25 (2%) were obese II. Mean operating time (214 min vs. 244 min vs. 293 min) and mean estimated blood loss (23 mL vs. 42 mL vs. 88 mL) increased significantly with increasing BMI (P<0.0001, respectively). The rate of postoperative complications was significantly higher in obese II patients than in nonobese and obese I patients (24% vs. 9.2% vs. 9.1%, P=0.0428). Multivariate analysis showed that a BMI in the obese II range was an independent predictive factor for developing anastomotic leakage (odds ratio: 10.27, 95% confidence interval, 1.98-53.44). Conclusions: Laparoscopic surgery for colorectal cancer is technically more demanding in Japanese obese II patients than in nonobese or obese I patients. Special care is required because of the increased risk of developing postoperative complications.


Digestive Surgery | 2009

Simultaneous Resection of Colorectal Cancer and Synchronous Liver Metastases: Initial Experience of Laparoscopy for Colorectal Cancer Resection

Takashi Akiyoshi; Hiroya Kuroyanagi; Akio Saiura; Yoshiya Fujimoto; Rintaro Koga; Tsuyoshi Konishi; Masashi Ueno; Masatoshi Oya; Makoto Seki; Toshiharu Yamaguchi

Background/Aims:Although laparoscopy is accepted for treatment of colorectal cancer, there is no established consensus for its use when resection of synchronous liver metastases is performed simultaneously. The purpose of this study was to evaluate whether laparoscopic colorectal resection with simultaneous resection of synchronous liver metastases was technically feasible and whether it may be a therapeutic option. Methods: Ten patients underwent laparoscopic resection for primary colorectal cancer, combined with synchronous resection of liver metastases. Results: The primary tumor location was in the sigmoid colon in 3 patients and the rectum in 7. All laparoscopic colorectal resections were successful, with no conversion to open surgery. Simultaneously, there were 7 conventional open and 3 laparoscopy-assisted liver resections. The median total operating time was 446 (range 300–745) min, including 222 (range 152–313) min for colorectal resection. The median total estimated blood loss was 175 (range 30–1,200) ml, including 10 (range 0–550) ml for colorectal resection. There was no major morbidity, except 1 patient who developed decubitus. Conclusion: This preliminary report suggests that laparoscopic resection for sigmoid colon and rectal cancer, combined with synchronous resection of liver metastases, is a safe and feasible procedure in selected patients.


World Journal of Gastrointestinal Surgery | 2010

Treatment of colorectal carcinoids: A new paradigm

Tsuyoshi Konishi; Toshiaki Watanabe; Hirokazu Nagawa; Masatoshi Oya; Masashi Ueno; Hiroya Kuroyanagi; Yoshiya Fujimoto; Takashi Akiyoshi; Toshiharu Yamaguchi; Tetsuichiro Muto

It is often difficult to evaluate the grade of malignancy and choose an appropriate treatment for colorectal carcinoids in clinical settings. Although tumor size and depth of invasion are evidently not enough to stratify the risk of this rare tumor, the present guidelines or staging systems do not mention other clinicopathological variables. Recent studies, however, have shed light on the impact of lymphovascular invasion on the outcome of colorectal carcinoids. It has been revealed that the presence of lymphovascular invasion was among the strongest risk factors for metastasis along with tumor size and depth of invasion. Furthermore, tumors smaller than 1 cm, within submucosal invasion and without lymphovascular invasion, carry minimal risk for metastasis with 100% 5-year survival in the studies from Japan as well as from the USA. This would suggest that these tumors could be curatively treated by endoscopic resection or transanal local excision. On the other hand, colorectal carcinoids with either lymphovascular invasion or tumor size larger than 1 cm carry the risk for metastasis equivalent to adenocarcinomas. Therefore, it should be emphasized that histological examination of lymphovascular invasion is mandatory in the specimens obtained by endoscopic resection or transanal local excision, as this would provide useful information for determining the need for additional radical surgery with regional lymph node dissection. Although the present guidelines or TNM staging system do not mention the impact of lymphovascular invasion, this would be among the next promising targets in order to establish better guidelines and staging systems, particularly in early-stage colorectal carcinoids.


Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2011

Colon cancer in the splenic flexure: comparison of short-term outcomes of laparoscopic and open colectomy.

Masayuki Nakashima; Takashi Akiyoshi; Masashi Ueno; Yosuke Fukunaga; Satoshi Nagayama; Yoshiya Fujimoto; Tsuyoshi Konishi; Rota Noaki; Keiko Yamakawa; Yasutomo Nagasue; Hiroya Kuroyanagi; Toshiharu Yamaguchi

Background: Laparoscopic surgery for colon cancer in the splenic flexure (SF cancer) is technically demanding and has not been evaluated in randomized clinical trials. This study aimed to evaluate the safety and feasibility of laparoscopic surgery for SF cancer. Methods: Thirty-three patients undergoing laparoscopic surgery for SF cancer (LAC group) were retrospectively compared with 22 patients undergoing open surgery for SF cancer (OC group) between April 2003 and June 2010. Results: Left hemicolectomy was the most performed procedure in both groups (79% vs. 82%). Median operating time was significantly longer (209 vs. 178 min) and estimated blood loss was significantly lower (15 vs. 113 mL) in the LAC group than in the OC group. Conversion to open surgery was needed for 1 (3%) patient because of bleeding near the pancreas. Tumor stage was more advanced in the OC group than in the LAC group, but N stages were similar between groups. The median number of lymph nodes harvested was significantly higher in the LAC group than in the OC group (16 vs. 12). The rate of postoperative complications was significantly lower in the LAC group than in the OC group (6% vs. 36%). Time to flatus (1 vs. 3 d), time to liquid diet (2 vs. 5 d), and hospital stay (12 vs. 16 d) were significantly shorter in the LAC group than in the OC group. Conclusions: Laparoscopic surgery for SF cancer is feasible.


American Journal of Surgery | 2011

Prognostic factors for survival after salvage surgery for locoregional recurrence of colon cancer.

Takashi Akiyoshi; Yoshiya Fujimoto; Tsuyoshi Konishi; Hiroya Kuroyanagi; Masashi Ueno; Masatoshi Oya; Satoshi Miyata; Toshiharu Yamaguchi

BACKGROUND Although locoregional recurrence after rectal cancer resection has been extensively investigated, studies of salvage surgery for locoregionally recurrent colon cancer are scarce. This study aimed to determine the predictors of postsalvage survival for locoregionally recurrent colon cancer. METHODS We studied 45 consecutive patients who underwent macroscopically complete resection of locoregionally recurrent colon cancer between April 1988 and December 2007. The primary end point was cancer-specific survival, and 20 clinical variables were analyzed for their prognostic significance. RESULTS Cancer-specific 5-year survival for the entire cohort of 45 patients was 46%. Multivariate survival analysis showed that margin status (P = .0311), number of locoregional recurrent tumors (P = .0002), pathological grade (P = .0416), largest tumor diameter (P = .0247), and distant metastasis (P = .0006) were independently associated with cancer-specific survival. CONCLUSIONS Salvage surgery for locoregional recurrence of colon cancer can provide a chance for long-term survival in selected patients.


Surgical Endoscopy and Other Interventional Techniques | 2010

Introduction of laparoscopic low anterior resection for rectal cancer early during residency: a single institutional study on short-term outcomes

Satoshi Ogiso; Takashi Yamaguchi; Hiroaki Hata; Hiroya Kuroyanagi; Yoshiharu Sakai

BackgroundLaparoscopic surgery for rectal cancer is unpopular because it is technically challenging. Suitable training systems have not been widely studied or established despite the steep learning curve for this procedure. We developed a systematic training program that enables resident surgeons to perform laparoscopic low anterior resection (LLAR) for rectal cancer and evaluated the safety and feasibility of this training program.MethodsWe analyzed prospectively gathered data on all LLARs for rectal cancer performed at a single center over a 7-year period. Patients were assessed for demographic characteristics, tumor characteristics, operative procedure, operative time, blood loss, conversion to open surgery, complications, time to bowel recovery, distal margin, and number of lymph nodes harvested. We compared the early surgical, oncological, and functional outcomes of LLARs performed by expert surgeons with those of LLARs performed by resident surgeons for both intraperitoneal and extraperitoneal rectal cancer. All analyses were performed on an intention-to-treat basis.ResultsA total of 137 patients met the inclusion criteria for this study. Of the 75 LLARs for intraperitoneal rectal cancer, 40 were performed by expert surgeons (I-E group) and 35 by resident surgeons (I-R group). Of the 62 LLARs for extraperitoneal rectal caner, 51 were performed by expert surgeons (E-E group) and 11 by resident surgeons (E-R group). The operative time was longer in the E-R group than in the E-E group. The time to resumption of diet was longer in the I-E group than in the I-R group. The other early outcomes, including blood loss, anastomotic leakage, conversion to open surgery, and number of lymph nodes harvested, were similar in the I-E and I-R groups and in the E-E and E-R groups.ConclusionOur systematic training program on LLAR for rectal cancer enables resident surgeons to perform this procedure safely early during residency, with acceptable short-term outcomes.


World Journal of Surgery | 2009

Risk Factors for Complications After Laparoscopic Surgery in Colorectal Cancer Patients: Experience of 401 Cases at a Single Institution

Koya Hida; Takashi Yamaguchi; Hiroaki Hata; Hiroya Kuroyanagi; Satoshi Nagayama; Harue Tada; Satoshi Teramukai; Masanori Fukushima; Kinya Koizumi; Yoshiharu Sakai

BackgroundLaparoscopic surgery is widely used for the treatment of colorectal cancer, but little is known about perioperative risk factors for complications.MethodsClinical data were reviewed for 401 consecutive unselected colorectal cancer patients who underwent laparoscopic surgery at Kyoto Medical Center between 1998 and 2005. The outcome variable was incidence of postoperative complications. Using logistic regression analysis, 58 background, clinical, preoperative, and intraoperative factors were assessed as potential predictors of complications.ResultsThe set of independent protective factors that had the greatest influence on the incidence of local complications after colon surgery was as follows: cefmetazole use for prophylaxis (versus oral only; adjusted odds ratio (OR) 0.18, 95% confidence interval (CI) 0.06–0.54), high operative infusion rate (per ml/min; OR 0.82, 95% CI 0.70–0.95), regular laxative use (OR 0.33, 95% CI 0.12–0.79), and double-stapled anastomosis (versus hand-sewn; OR 0.15, 95% CI 0.03–0.83). Independent risk factors for local complications after rectal surgery were abdominoperineal resection (versus low anterior resection, OR 4.84, 95% CI 1.64–14.9), long operative time (per hour, OR 1.55, 95% CI 1.11–2.23), and history of heart disease (OR 5.18, 95% CI 1.34–21.5). The occurrence of complications was not found to be associated with overall survival in this study.ConclusionsWe identified intraoperative management such as low operative infusion rate is one of the independent significant risk factors for complications after laparoscopic surgery for colorectal cancer in addition to patient characteristics and surgical procedure.

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Masashi Ueno

Japanese Foundation for Cancer Research

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Yoshiya Fujimoto

Japanese Foundation for Cancer Research

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Toshiharu Yamaguchi

Japanese Foundation for Cancer Research

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Takashi Akiyoshi

Japanese Foundation for Cancer Research

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Masatoshi Oya

Japanese Foundation for Cancer Research

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Tsuyoshi Konishi

Japanese Foundation for Cancer Research

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Tetsuichiro Muto

Japanese Foundation for Cancer Research

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Satoshi Nagayama

Japanese Foundation for Cancer Research

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Yosuke Fukunaga

Japanese Foundation for Cancer Research

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