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Featured researches published by Tsunekazu Hanai.


Diseases of The Colon & Rectum | 2004

Irrigation Volume Determines the Efficacy of “Rectal Washout”

K. Maeda; M. Maruta; Tsunekazu Hanai; Harunobu Sato; Yoshimune Horibe

PURPOSERectal stump washout has been recommended to prevent implantation of exfoliated malignant cells in the anastomosis after anterior resection for rectal cancer. The aim of this study was to investigate its efficacy, particularly the extent to which the volume of irrigation fluid might influence the efficacy of tumor cell elimination and whether tumor characteristics might influence the result.METHODSThe study comprised 30 consecutive patients operated on by anterior resection for rectal cancer. After cross-clamping the rectum below the tumor, a washout sample was collected for examination after every incremental 500 ml of saline irrigation up to 2 liters. The presence of shed cancer cells was correlated with the washout volume and tumor characteristics.RESULTSCancer cells were found in 29 of 30 patients (97 percent) in the first sample of irrigation fluid and decreased gradually in frequency and number with increasing irrigation volumes. No cancer cells were demonstrated after 1.5 liters of irrigation in patients with tumor below the peritoneal reflection, whereas cancer cells were still present in one-fourth of the patients with tumor located above the peritoneal reflection. Finally, only a small number of cancer cells was confirmed in one patient after 2 liters of irrigation.CONCLUSIONSThe irrigation volume determined the efficacy of rectal washout. With our method, 1 1/2 liters of saline irrigation appears to clear contents from cancer cells in patients with tumors below the peritoneal reflection whereas at least 2 liters is recommended for patients with tumor above the peritoneal reflection.


Journal of The American College of Surgeons | 2001

Laparoscopic lateral node dissection with autonomic nerve preservation for advanced lower rectal cancer

Ichiro Uyama; Atsushi Sugioka; Hideo Matsui; Junko Fujita; Yoshiyuki Komori; Tsunekazu Hanai; Akitake Hasumi

In Japan, radical resection with autonomic nerve preservation and lateral node dissection is standard surgery for advanced lower rectal cancers. But this operation has never been performed laparoscopically because many surgeons consider laparoscopic lateral node dissection with nerve preservation to be technically difficult, and any resulting insufficiency of the lateral lymph node dissection may reduce the curability of a patient’s cancer. Nonetheless, laparoscopic resection without lateral lymph node dissection is commonly performed for colorectal cancer to reduce the surgical invasiveness. Recently, we successfully performed laparoscopic radical resection with autonomic nerve preservation and lateral lymph node dissection in five patients with advanced lower rectal cancer. We describe here our surgical procedure and our initial clinical results.


Surgery Today | 2005

Modified Double-Stapling Technique in Low Anterior Resection for Lower Rectal Carcinoma

Harunobu Sato; K. Maeda; Tsunekazu Hanai; M. Matsumoto; H. Aoyama; Hiroshi Matsuoka

PurposeThe original double-stapling technique (DST) using a standard linear stapler horizontally can be difficult in patients with a narrow pelvis or an ultralow anastomosis. We review our experience of performing a modified DST (IO-DST) with vertical division of the rectum achieved using an endostapler.MethodsWe retrospectively studied the clinical outcomes of 90 patients who underwent low anterior resection (LAR) for lower rectal carcinoma. Low anterior resection was performed with IO-DST in 34 patients (IO-DST group), with the single-stapling technique (SST) in 47 (SST group), and with per anal anastomosis (PAA) in 9 (PAA group).ResultsThe distances from the anal verge to the tumor and to the anastomosis were significantly shorter in the IO-DST group than in the SST group (5.8 cm, 4.0 cm vs 7.0 cm, 5.0 cm, respectively), whereas it was equivalent in the IO-DST and PAA groups (5.0 cm, 4.0 cm). Blood loss was less in the IO-DST group than in the SST and PAA groups (400 ml vs 578 ml and 950 ml, respectively). The operative time was shorter in the IO-DST group than in the PAA group (281 min vs 327 min, respectively). There were no significant differences in the length of the distal surgical margin among the three groups. The IO-DST group patients suffered less bowel frequency than the SST group patients 1 month after surgery (2.5 times/day vs 4.0 times/day, respectively) and less than the PAA group patients more than 1 year after surgery (2.0 times/day vs 3.5 times/day, respectively). There were no significant differences in the incidence of complications or local recurrence among the three groups.ConclusionsIO-DST is a feasible and safe procedure for performing low anastomosis, which results in less bowel frequency after LAR for lower rectal carcinoma.


Digestive Surgery | 2015

Novel Antimesenteric Functional End-to-End Handsewn (Kono-S) Anastomoses for Crohn's Disease: A Report of Surgical Procedure and Short-Term Outcomes

Hidetoshi Katsuno; K. Maeda; Tsunekazu Hanai; Koji Masumori; Yoshikazu Koide; Toru Kono

Introduction: Anastomotic surgical recurrence after bowel resection is a major problem in patients with Crohns disease. The aim of this prospective observational study was to evaluate the efficacy of a novel technique for restoring bowel continuity after resection involving either the small or the large intestine. Methods: The first case was instructed by Dr. Kono at Fujita Health University. The involved bowel segment was divided transversely with a linear stapler. The edges of two stapled lines are then connected to create a supporting column, which prevented surgical recurrence from anastomotic distortion due to mesenteric longitudinal ulcers. Thereafter, an antimesenteric longitudinal enterotomy was performed on each side to create a large-sized handsewn end-to-end anastomosis. Results: Thirty consecutive patients underwent Kono-S anastomoses from December 2009 to August 2013. Neither anastomotic leakage nor surgical recurrence was observed during a median follow-up period of 35 months. Endoscopic surveillance was performed in 18 cases (69.2%) undergoing ileo-colonic or ileo-rectal anastomosis with an average Rutgeerts score of 0.78 (0-3) at a mean of 14.5 months postoperatively. Conclusion: The Kono-S anastomosis for Crohns disease has been a safe and feasible technique. Long-term outcomes are required to confirm its advantage in preventing surgical recurrence at the anastomosis.


Breast Cancer | 1997

The Relation between Superoxide Dismutase in Cancer Tissue and Clinico-pathological Features in Breast Cancer.

Katsumi Iwase; Kanefusa Kato; Susumu Ohtani; Toru Tsujimura; Tsunekazu Hanai; Asako Inagaki; Shin Jimbo; Naomi Kobayashi; Haruo Yamamoto; Akio Nagasaka; Kaoru Miura

The localization of Cu/Zn- and Mn-superoxide dismutase (SOD) in breast cancer tissue (12 papillotubular carcinomas, 21 solid-tubular carcinomas, 16 scirrhous carcinomas, 1 medullary carcinoma, 1 secreting carcinoma, 1 lobular carcinoma, 1 Paget’s disease) was investigated via an immunohistochemical technique using antihuman Cu/Zn- and Mn-SOD antibodies in 10% formalin fixed-paraffin embedded thin sections. Both SODs stained strongly in the normal breast gland, but not clearly in many cancer tissues. Furthermore, Cu/Zn-SOD stained more strongly in well differentiated tubular carcinomas than in poorly differentiated tubular carcinomas. It tended to stain less in tumors which recurred or had a poor outcome, and in tumors with a diploid pattern on DNA flow cytometry. Mn-SOD staining was similar to that of Cu/Zn-SOD, but no significant differences among subgroups was found, since the incidence of positively staining tumors was too small in all groups. The intensity of SOD staining seems to change in relation to cell proliferation and differentiation in breast carcinoma, and may be a prognostic indicator, since SOD decreased in poorly differentiated carcinoma and in tumors which developed distant metastasis. Thus, the localization of SOD in breast cancer tissue can provide useful information for cancer treatment.


Surgery Today | 2011

Trans-sacral resection of a solitary fibrous tumor in the pelvis: Report of a case

Hidetoshi Katsuno; K. Maeda; Tsunekazu Hanai; Harunobu Sato; Koji Masumori; Yoshikazu Koide; Hiroshi Matsuoka; Tomohito Noro; Yasunari Takakuwa; Ryouta Hanaoka

Solitary fibrous tumors (SFTs) develop most commonly in the pleura, although they have occasionally been reported to arise in the pelvic cavity. We report a case of an SFT presenting as a painless nodule in the pelvis of a 56-year-old woman. Histologically, the tumor was composed of spindle-shaped cells arranged without pattern, with short and narrow fascicles and interspersed bundles of thick collagen, and numerous blood vessels with a focally hemangiopericytoma-like appearance. Immunohistochemically, the tumor cells strongly expressed vimentin, CD34, and bcl-2. The tumor was excised via a trans-sacral approach, without preoperative transcatheter embolization, and the patient remains well more than 2 years after her operation. To our knowledge, this is the first case of an SFT in the pelvis, which was excised completely via a trans-sacral approach.


Asian Journal of Endoscopic Surgery | 2017

Laparoscopic versus open resection for transverse and descending colon cancer: Short-term and long-term outcomes of a multicenter retrospective study of 1830 patients

Shigeki Yamaguchi; Jo Tashiro; Ryuichiro Araki; Junji Okuda; Tsunekazu Hanai; Koki Otsuka; Shuji Saito; Masahiko Watanabe; Kenichi Sugihara

Previous randomized controlled trials demonstrated similar oncological outcomes between laparoscopic and open colectomies, except for cases involving transverse colon and splenic flexure colon cancer. The objective of this study was to confirm the oncological safety and advantages of the short‐term results of laparoscopic surgery for transverse and descending colon cancer in comparison with open surgery.


Asian Journal of Surgery | 2016

Surgical management of colorectal cancer for the aging population—A survey by the Japanese Society for Cancer of Colon and Rectum

Hiroshi Matsuoka; Kotaro Maeda; Tsunekazu Hanai; Harunobu Sato; Koji Masumori; Y. Koide; Hidetoshi Katsuno; Tomoyoshi Endo; Miho Shiota; Kenichi Sugihara

OBJECTIVE The treatment policy of colorectal cancer in elderly patients is controversial due to a lack of specific guidelines. To clarify the present management of colorectal cancer for aged patients, a questionnaire survey was conducted by the Japanese Society for Cancer of the Colon and Rectum. METHODS Questionnaire forms were sent to the 430 member institutions of the Japanese Society for Cancer of the Colon and Rectum. RESULTS The response rate of the surgical department to the questionnaire was 39%. Performance status was used for preoperative assessments, and electrocardiogram and ultrasonic cardiograms were conducted for cardiovascular evaluations in many institutions. The same extent of surgical procedures was often adopted for elderly and younger patients, and the frequency of a laparoscopic procedure was the same regardless of a patients age. A simultaneous hepatectomy for hepatic metastasis was considered in one-third of institutions. In many institutions, intersphincteric resection for patients with possible sphincter-saving surgery was not considered for elderly patients with low rectal cancer. CONCLUSION Japanese Society for Cancer of the Colon and Rectum member institutions often used the same surgical treatment strategies for both elderly and younger patients with the exception of performing intersphincteric resection.


Journal of the Anus, Rectum and Colon | 2018

Successful repair of a rectovaginal fistula caused by a tension-free vaginal mesh (TVM): a case report

Yoshikazu Koide; Kotaro Maeda; Tsunekazu Hanai; Koji Masumori; Hiroshi Matuoka; Hidetoshi Katsuno; Tomoyoshi Endo; Miho Shiota; Masahiro Mizuno; Yeong Cheol Cheong

Rectovaginal fistula caused by a tension-free vaginal mesh (TVM) is a rare condition. Moreover, a rectovaginal fistula is a challenging issue to address for surgeons regardless of causes. Due to a low rate of occurrence, treatment modality for a rectovaginal fistula caused by a TVM has previously received little attention. A successful surgery using several key techniques to address a rectovaginal fistula caused by a TVM is herein reported. A 78-year-old woman who underwent a TVM for a rectocele three months ago was referred to our hospital with a two-month history of anal bleeding. Mesh protruding into both the vagina and the rectum was confirmed. The patient was operated on under diagnosis of a rectovaginal fistula caused by TVM. TVM was removed by transvaginal dissection of the rectovaginal septum with division of both anterior and posterior arms of the TVM. Layer-to-layer sutures of rectal and vaginal walls were crossly performed with a drain placed in the rectovaginal septum after saline irrigation followed by a covering sigmoid colostomy. The wound healed without infection after surgery, and a water-soluble contrast enema demonstrated the healing of the rectovaginal fistula two months after surgery. No recurrent fistula was confirmed 15 months after stoma closure.


Journal of The American College of Surgeons | 2004

Hand-assisted laparoscopic function- preserving and radical gastrectomies for advanced-stage proximal gastric cancer1

Ichiro Uyama; Atsushi Sugioka; Yoichi Sakurai; Yoshiyuki Komori; Tsunekazu Hanai; Hideo Matsui; Junko Fujita; Yasuko Nakamura; Masahiro Ochiai; Akitake Hasumi

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K. Maeda

Fujita Health University

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Harunobu Sato

Fujita Health University

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Asako Inagaki

Fujita Health University

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