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Featured researches published by Tadao Tokoro.


Diseases of The Colon & Rectum | 2004

Comparison of Long-Term Functional Results of Colonic J-Pouch and Straight Anastomosis After Low Anterior Resection for Rectal Cancer: A Five-Year Follow-Up

Jin-ichi Hida; Takehito Yoshifuji; Tadao Tokoro; Kiyohiko Inoue; Tomohiko Matsuzaki; Kiyotaka Okuno; Hitoshi Shiozaki; Masayuki Yasutomi

PURPOSEFew reports on the long-term functional outcome of colonic J-pouch reconstruction have been published, and data comparing J-pouch and straight reconstruction are contradictory. This prospective study compares the functional outcome of colonic J-pouch and straight anastomosis five years after low anterior resection for rectal cancer.METHODSFunctional outcome was compared in 46 patients with J-pouch reconstruction (J-group) and 48 patients with straight anastomosis (S-group). Clinical status was evaluated with a 17-item questionnaire inquiring about different aspects of bowel function. Reservoir function was evaluated by manovolumetry. The Fisher’s exact test and Wilcoxon’s rank-sum test were used to compare categoric and quantitative data, respectively.RESULTSAmong patients with an ultralow anastomosis (≤4 cm from the anal verge), the number of bowel movements during the day (≥5, 4.3 vs. 29.2 percent; P = 0.028) and at night (>1/week, 4.3 vs. 33.3 percent; P = 0.013) and urgency (4.3 vs. 33.3 percent; P = 0.013) and soiling (21.7 vs. 50.0 percent; P = 0.043) were less in the J-group than in the S-group. Among patients with a low anastomosis (5 to 8 cm from the verge), patients in the J-group had fewer bowel movements at night (>1/week, 0 vs. 20.8 percent; P = 0.028) and less urgency (0 vs. 20.8 percent; P = 0.028). Reservoir function was better in the J-group than in the S-group in both the ultralow (maximum tolerable volume (mean), 101.7 vs. 76.3 ml; P = 0.004; threshold volume (mean), 46.5 vs. 30.4 ml; P < 0.001; compliance (mean), 4.9 vs. 2.5 ml/cm H2O; P < 0.001) and low-anastomosis (maximum tolerable volume, 120.4 vs. 97.9 ml; P < 0.001; threshold volume, 58.3 vs. 40.8 ml; P < 0.001; compliance, 5.2 vs. 3.1 ml/cm H2O; P < 0.001) groups.CONCLUSIONSJ-pouch reconstruction increased reservoir function and provided better functional outcome than straight anastomosis, even five years after surgery, especially in patients whose anastomosis is less than 4 cm from the anal verge.


Diseases of The Colon & Rectum | 1999

Enlargement of colonic pouch after proctectomy and colonanal anastomosis: Potential cause for evacuation difficulty

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Tadao Tokoro; Tsukasa Wakano; Toshihiro Uchida

PURPOSE: Although the functional outcome after low anterior resection for rectal cancer using colonic J-pouch reconstruction is superior to that using conventional straight reconstruction, the one drawback of colonic J-pouch reconstruction is difficulty with evacuation. Recently it has been suggested that construction of a larger colonic J-pouch causes the evacuation difficulty. The purpose of this study was to elucidate the cause of evacuation difficulty with colonic J-pouch reconstruction. METHODS: We compared pouchography of 26 patients with 10-cm colonic J-pouch reconstructions (10-J group) and 27 patients with 5-cm colonic J-pouch reconstructions (5-J group) at three months, one year, and two years after surgery. Functional assessments were performed one year postoperatively. Clinical function was evaluated using a questionnaire. Evacuation function was evaluated by the balloon expulsion and saline evacuation tests. RESULTS: The greatest width of the pouch in the 10-J group in the anteroposterior view was significantly greater than that in the 5-J group at all three measurement times (3 months, 4.9vs. 4 cm;P=0.0011; 1 year, 9vs. 5.6 cm;P<0.0001; 2 years, 9.2vs. 5.8 cm;P<0.0001). The value in the 10-J group at one year after surgery was 1.9 times that at three postoperative months; in the 5-J group this ratio was 1.4. There was a significant difference between these ratios (P<0.0001). No significant difference existed between the values at two years and one year after surgery in either the 10-J or the 5-J group. An evacuation difficulty was significantly more common in the 10-J group than the 5-J group. Evacuation function in the 10-J group was significantly inferior to that in the 5-J group. CONCLUSIONS: The evacuation difficulty observed in patients with larger colonic J-pouch reconstructions is associated with excessive distention of the pouch occurring within one year of surgery.PURPOSE Although the functional outcome after low anterior resection for rectal cancer using colonic J-pouch reconstruction is superior to that using conventional straight reconstruction, the one drawback of colonic J-pouch reconstruction is difficulty with evacuation. Recently it has been suggested that construction of a larger colonic J-pouch causes the evacuation difficulty. The purpose of this study was to elucidate the cause of evacuation difficulty with colonic J-pouch reconstruction. METHODS We compared pouchography of 26 patients with 10-cm colonic J-pouch reconstructions (10-J group) and 27 patients with 5-cm colonic J-pouch reconstructions (5-J group) at three months, one year, and two years after surgery. Functional assessments were performed one year postoperatively. Clinical function was evaluated using a questionnaire. Evacuation function was evaluated by the balloon expulsion and saline evacuation tests. RESULTS The greatest width of the pouch in the 10-J group in the anteroposterior view was significantly greater than that in the 5-J group at all three measurement times (3 months, 4.9 vs. 4 cm; P = 0.0011; 1 year, 9 vs. 5.6 cm; P < 0.0001; 2 years, 9.2 vs. 5.8 cm; P < 0.0001). The value in the 10-J group at one year after surgery was 1.9 times that at three postoperative months; in the 5-J group this ratio was 1.4. There was a significant difference between these ratios (P < 0.0001). No significant difference existed between the values at two years and one year after surgery in either the 10-J or the 5-J group. An evacuation difficulty was significantly more common in the 10-J group than the 5-J group. Evacuation function in the 10-J group was significantly inferior to that in the 5-J group. CONCLUSIONS The evacuation difficulty observed in patients with larger colonic J-pouch reconstructions is associated with excessive distention of the pouch occurring within one year of surgery.


Diseases of The Colon & Rectum | 1998

Results from pelvic exenteration for locally advanced colorectal cancer with lymph node metastases

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Akihiro Nakajima; Toshihiro Uchida; Tsukasa Wakano; Tadao Tokoro; Kiyoshige Fujimoto

PURPOSE: We examined the survival benefit of pelvic exenteration for locally advanced colorectal cancer with lymph node metastases, because this issue remains controversial. METHODS: Medical records of 50 patients who underwent curative pelvic exenteration for colorectal cancer were reviewed retrospectively. Nodal metastases were examined by the clearing method in 29 patients and by the conventional manual method in 21 patients. RESULTS: Invasion to contiguous pelvic organs was present in 40 patients (80 percent) and absent in 10 patients (20 percent). Node metastases were present in 33 patients (66 percent). Operative morbidity and mortality rates were 22 percent (11 patients) and 6 percent (3 patients), respectively. Respective five-year survival rates were 60 and 80 percent in the groups with and without organ invasion (no significant difference). Five-year survival rates in patients with nodal metastases was 54.6 percent but was significantly higher, 82.4 percent, in patients without nodal metastases. Five-year survival in 28 patients with both organ invasion and nodal metastases was 53.6 percent. CONCLUSIONS: Long-term survival was afforded by pelvic exenteration for locally advanced colorectal cancer with nodal metastases.


Diseases of The Colon & Rectum | 2005

Optimal ligation level of the primary feeding artery and bowel resection margin in colon cancer surgery: the influence of the site of the primary feeding artery.

Jin-ichi Hida; Kiyotaka Okuno; Masayuki Yasutomi; Takehito Yoshifuji; Toshihiro Uchida; Tadao Tokoro; Hitoshi Shiozaki

PURPOSEIn colon cancer surgery, it is recommended that en bloc resection involving extended lymphadenectomy, characterized as a hemicolectomy, be performed by ligating the primary feeding artery at a high position and resecting proximal and distal with 5-cm to 10-cm bowel margins. However, there is little evidence to unequivocally support such extensive lymphovascular resection.METHODSThe distribution of nodal metastases was obtained by the clearing method in 164 patients with colon cancer.RESULTSFor pericolic spread, for pT1 tumors, the distance from the primary tumor to a diseased node was 2.5 cm; for pT2, the distance was less than 5 cm; for 97.0 percent of pT3 tumors and 93.3 percent of pT4 tumors with nodes involved, the distance was less than 7 cm. For central spread, for pT1 tumors, the rate of spread to central nodes was 0 percent; for pT2, the rate of spread was 20.0 percent to intermediate nodes (for tumors more than 5 cm from the feeding artery, the rate for central nodes was 0 percent); for pT3, the rate was 30.6 percent to intermediate nodes and 15.3 percent to main nodes; for pT4, the rate was 44.4 percent to intermediate nodes and 22.2 percent to main nodes. For curative resection cases with pT3 tumors more than 7 cm from the feeding artery, the rate to central nodes was 0 percent.CONCLUSIONSIn T1 tumors, central node dissection is not required, but resection with proximal and distal 3-cm margins are required; in T2, central node dissection that includes the intermediate node should be performed in addition to resection with proximal and distal 5-cm margins. In T3 and T4, central node dissection that includes the main node should be performed in addition to resection with proximal and distal 7-cm margins. However, for T2 more than 5 cm from the primary feeding artery, and for T3 more than 7 cm from the primary feeding artery, proximal and distal resection alone may be adequate.


Archive | 1998

Indications for colonic J-pouch reconstruction after anterior resection for rectal cancer

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Kiyoshige Fujimoto; Akihiro Nakajima; Toshihiro Uchida; Tsukasa Wakano; Tadao Tokoro; Ryuichi Kubo; Katsuhisa Shindo

PURPOSE: Functional outcome after anterior resection for rectal cancer is improved by colonic J-pouch reconstruction compared with straight anastomosis. The indications for colonic J-pouch reconstruction have yet to be determined. Therefore, we attempted to determine the level at which J-pouch reconstruction provides an advantage over straight anastomosis. METHODS: A total of 48 patients who underwent 5-cm colonic J-pouch reconstruction (J-pouch group) and 80 patients who underwent straight anastomosis (straight group) underwent functional assessment one year postoperatively. RESULTS: The functional outcome in the J-pouch group was significantly better than that in the straight group when the distance of the anastomosis from the anal verge was less than 8 cm. The difference was particularly obvious when the level of the anastomosis was below 4 cm. However, functional outcome in the straight group when the anastomosis was between 9 and 12 cm from the anal verge was also satisfactory and did not differ from that in the J-pouch group when the anastomosis was between 5 and 8 cm from the anal verge. CONCLUSIONS: Colonic J-pouch reconstruction is indicated when the distance of anastomosis from the anal verge is less than 8 cm, and it is essential when the distance is less than 4 cm.


Archive | 1998

Indication for using high ligation of the inferior mesenteric artery in rectal cancer surgery

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Kiyoshige Fujimoto; Akihiro Nakajima; Toshihiro Uchida; Tsukasa Wakano; Tadao Tokoro; Ryuichi Kubo; Katsuhisa Shindo

PURPOSE: In surgery for rectal cancer, it is unclear whether the inferior mesenteric artery should be ligated at a high or low position. The study contained herein was undertaken to clarify the indications for high ligation of the inferior mesenteric artery. METHODS: Subjects included 198 patients with rectal cancer who underwent resection with high ligation of the inferior mesenteric artery. Nodal metastases were examined by the clearing method. RESULTS: The incidence of metastases to the lymph nodes surrounding the origin of the inferior mesenteric artery (root nodes) was 8.6 percent. Inferior mesenteric artery root nodal metastases occurred more frequently with pT3 and pT4 cancer. The five-year survival rate in patients with inferior mesenteric artery root nodal metastases was 38.5 percent; this rate was significantly lower than in those without inferior mesenteric artery root nodal metastases (73.4 percent). CONCLUSIONS: Although the five-year survival rate in patients with inferior mesenteric artery root nodal metastases was lower than in those without metastases, inferior mesenteric artery root nodal dissection should be performed after high ligation of the inferior mesenteric artery for patients with pT3 and pT4 cancers.


Diseases of The Colon & Rectum | 2004

Long-Term Functional Outcome of Low Anterior Resection With Colonic J-Pouch Reconstruction for Rectal Cancer in the Elderly

Jin-ichi Hida; Takehito Yoshifuji; Tadao Tokoro; Kiyohiko Inoue; Tomohiko Matsuzaki; Kiyotaka Okuno; Hitoshi Shiozaki; Masayuki Yasutomi

PURPOSE:Bowel function after low anterior resection for rectal cancer with colonic J-pouch reconstruction is more normal than after conventional straight anastomosis. However, few reports have examined the function of colonic J-pouch reconstruction in the elderly. Good function would obviate the need for colostomy, which is sometimes performed because of concern about fecal incontinence, which increases with age. This study evaluated the function of colonic J-pouch reconstruction in elderly patients aged 75 years or older.METHODS:Functional outcome was compared in 20 patients aged 75 years or older (older group) and 27 patients aged 60 to 74 years (old group) and 60 patients aged 59 years or younger (young group), 3 years after colonic J-pouch reconstruction, using a functional scoring system with a 17-item questionnaire (score range, 0 (overall good) to 26 (overall poor)).RESULTS:The functional scores in the three age groups were satisfactory and similar. Among patients with anastomoses 1 cm to 4 cm from the anal verge, all 17 categories on the questionnaire in the three age groups were similar. Among patients with anastomoses 5 cm to 8 cm from the anal verge, only the use of laxatives or glycerine enemas was more common in the older group than in the old and young group (90 vs. 38.5 percent and 43.3 percent; P = 0.01).CONCLUSIONS:Low anterior resection with colonic J-pouch reconstruction provides excellent functional outcome, including continence, for elderly patients. Colonic J-pouch reconstruction is a highly preferable alternative to permanent colostomy in elderly patients undergoing low anterior resection.


Diseases of The Colon & Rectum | 1999

Examination of nodal metastases by a clearing method supports pelvic plexus preservation in rectal cancer surgery.

Jin-ichi Hida; Masayuki Yasutomi; Tadao Tokoro; Ryuichi Kubo

PURPOSE: In rectal cancer surgery preservation of urinary and sexual function is attempted by means of operations preserving the autonomic nerves of the pelvic plexus. Emergence of residual cancer because of a more shallow plane of dissection is a problem of concern with these methods, so we examined indications for pelvic plexus preservation. METHODS: We studied 198 patients with rectal carcinoma who underwent abdominopelvic lymphadenectomy. Lymph nodes along the superior hemorrhoidal artery and middle hemorrhoidal artery medial to the pelvic plexus were defined as perirectal nodes, and nodes along the middle hemorrhoidal artery lateral to the pelvic plexus and along the internal iliac artery represented lateral intermediate nodes. Node metastases were examined by the clearing method. RESULTS: Metastasis to perirectal nodes occurred in 12.5 percent in patients with pT1 tumors, 28.9 percent of those with pT2 tumors, and 50.0 percent of those with rectosigmoid junctional cancer. Metastasis to lateral intermediate nodes was absent in patients with pT1 or pT2 tumors and was as low as 2.5 percent in patients with rectosigmoid junctional cancer. CONCLUSIONS: In patients with T1, T2, and rectosigmoid junctional cancer, perirectal node dissection is necessary, but chances of residual cancer should remain minimal when the pelvic plexus is preserved.


Archive | 1999

Horizontal inclination of the longitudinal axis of the colonic J-pouch

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Tadao Tokoro; Toshihiro Uchida; Tsukasa Wakano; Ryuichi Kubo

PURPOSE: Functional outcome after low anterior resection for rectal cancer is improved by the construction of a colonic J-pouch. One disadvantage of this type of reconstruction is evacuation difficulty, which has been associated with large pouches. The purpose of this study was to elucidate the causes of evacuation difficulty in large pouches using pouchography. METHODS: The angle between the longitudinal axis of the pouch and the horizontal line (pouch-horizontal angle) on lateral pouchography was determined in 26 patients with 10-cm J-pouch reconstructions (10-J group) and 27 patients with 5-cm J-pouch reconstructions (5-J group). Measurement were made at three months, one year, and two years after surgery. Clinical function was evaluated using a questionnaire one year postoperatively. RESULTS: The pouch-horizontal angle in the 10-J group was significantly smaller than that in the 5-J group at all three time points. In both groups the pouch-horizontal angle at one year was significantly smaller than that at three months. There were no significant differences between the pouch-horizontal angles at one and two years. An evacuation difficulty was significantly more common in the 10-J group than the 5-J group. CONCLUSIONS: The evacuation difficulty observed in patients with large colonic J-pouch reconstructions may be attributed to the development of a horizontal inclination within one year of surgery.


Surgery Today | 1999

Detection of a rectocele-like prolapse in the colonic J-pouch using pouchography: cause or effect of evacuation difficulties?

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Takehito Yoshifuji; Tadao Tokoro; Tsukasa Wakano; Toshihiro Uchida; Kazuki Ueda

The functional outcome after a low anterior resection for rectal cancer is improved by a colonic J-pouch reconstruction. One functional problem with J-pouches is difficulty in evacuation, which is more common with large reconstructions. Since rectoceles are common findings on defecography in patients with evacuation difficulties, we proposed that a rectocele-like prolapse may be thus found in patients with large J-pouches. Pouchography was used to identifya rectocele-like prolapse (RP) in 26 patients with a 10-cm J-pouch (10-J group) and 27 patients with a 5-cm J-pouch (5-J group). Pouchography was performed at 3 months, 1 year, and 2 years after surgery. Functional assessments were performed 1 year postoperatively. Clinical function was evaluated using a questionnaire. The evacuation function was evaluated by the balloon expulsion and saline evacuation test. No patients had an RP at 3 months or 1 year after surgery. An RP was significantly more common in the 10-J group than in the 5-J group at 2 years after surgery (P=0.0374). An evacuation difficulty was significantly more common in the 10-J group than in the 5-J group. The evacuation function in the 10-J group was also significantly inferior to that in the 5-J group. An RP appearing 2 years after surgery is more common in patients with evacuation difficulties and large colonic J-pouch reconstructions.

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