Yuichi Tabe

Thickness of subcutaneous fat as a strong risk factor for wound infections in elective colorectal surgery: impact of prediction using preoperative CT.

Background/Aims:In this study, we have attempted to identify and assess factors that would be most predictive of postoperative incisional surgical site infection (SSI) in colorectal surgery, including representative markers for nutrition or obesity. Methods: 152 patients who underwent elective colorectal resection were identified for inclusion in this study. The outcome of interest was incisional SSI. Variables thought to be predictive of incisional SSI, including body mass index (BMI) and the thickness of subcutaneous fat (TSF), were assessed by univariate and multivariate analysis. TSF was evaluated preoperatively using computed tomography (CT). Results: The study’s overall incidence of incisional SSI following a colorectal operation was 29 (19.1%). TSF was independently associated with incisional SSI. While BMI was significantly associated with incisional SSI on univariate analysis, this variable lost its significance on multivariate analysis that included TSF. Other nutritional markers were not significantly associated with the risk of incisional SSI. Conclusions:Our results suggest that the risk of incisional SSI increases with obesity, and that the most useful predictor of incisional SSI is TSF, as evaluated by preoperative CT. These findings indicate that CT is useful for the evaluation of TSF and the prediction of the risk of incisional SSI.

Intragastric monosodium l-glutamate stimulates motility of upper gut via vagus nerve in conscious dogs

Monosodium l-glutamate (MSG) is a substance known to produce the umami taste. Recent studies indicate that MSG also stimulates a variety of activities in the gastrointestinal tract through its receptor in the gut, but no study has reported the activity in conscious large experimental animals. The aim of our study was to investigate whether direct intragastric MSG stimulates gut motility and to identify the mechanism in conscious dogs. Contractile response to intraluminal injection of MSG was studied in the fed and fasted states by means of chronically implanted force transducers. MSG (5, 15, 45, and 90 mM/kg) dissolved in water was injected into the stomach and duodenum in normal and vagotomized dogs. MSG solution was administered into the stomach before feeding, and gastric emptying was evaluated. Several inhibitors of gastrointestinal motility (atropine, hexamethonium, and granisetron) were injected intravenously before MSG administration to the stomach. The effect of MSG was investigated in Pavlov (vagally innervated corpus pouch), Heidenhain (vagally denervated corpus pouch), and antral pouch (vagally innervated) dogs. Upper gut motility was significantly increased by intragastric MSG but not significantly stimulated by intraduodenal MSG. Intragastric MSG (45 mM/kg) stimulated postprandial motility and accelerated gastric emptying. MSG-induced contractions were inhibited by truncal vagotomy, atropine, hexamethonium, and granisetron. Gut motility was increased by intrapouch injection of MSG in the Pavlov pouch, but it was not affected in the Heidenhain or antral pouch dogs. We conclude that intragastric MSG stimulates upper gut motility and accelerates gastric emptying. The sensory structure of MSG is present in the gastric corpus, and the signal is mediated by the vagus nerve.

Effect of distal subtotal gastrectomy with preservation of the celiac branch of the vagus nerve to gastrointestinal function: an experimental study in conscious dogs.

Objective:To evaluate the effects of distal subtotal gastrectomy with preservation of the celiac branch of the vagus nerve on gastrointestinal function. Summary Background Data:The operative procedure of distal subtotal gastrectomy with preservation of the celiac branch of the vagus nerve is now in the spotlight in Japan with the goal of finding a function-preserving surgical technique. However, there has been no analysis of the effect of this type of surgery on gastrointestinal function. In this article, we describe the results of a fundamental experiment on distal subtotal gastrectomy with preservation of the celiac branch of the vagus nerve. Methods:Twenty conscious dogs were divided into 2 groups, each subdivided into 2 groups of 5: a normal intact dog group (NG) divided into 2 groups, with preservation (PNG) and resection (RNG; these dogs were truncally vagotomized including transaction of the celiac branch) of the celiac branch, and a gastrectomy dog group (GG) divided into 2 groups, with preservation (PGG) and resection (RGG) of the celiac branch. The motility of the dogs was recorded using strain gauge force transducers. The effects of the preservation of the celiac branch of the vagus nerve on gastrointestinal motility, gastric emptying, and pancreatic insulin release were evaluated. Results:The motility index of gastrointestinal motility with preservation of the celiac branch was higher than the motility index with resection of the celiac branch in fasted and fed of NG and GG. In gastric emptying, significant differences were found between the PNG and RNG but not between the PGG and RGG. In the fasted state for 80 minutes of the PNG and PGG, the serum insulin concentration reached a peak during the early phase III at 20 minutes in the gastric body and the antrum. Conclusions:This study has shown that it is effective to preserve the celiac branch of the vagus nerve for gastroduodenal motility, gastric emptying, and pancreatic insulin release after a gastrectomy.

Process of distant lymph node metastasis in colorectal carcinoma: Implication of extracapsular invasion of lymph node metastasis

BackgroundWe previously demonstrated that extracapsular invasion (ECI) at a metastatic sentinel node was significantly associated with the presence of positive non-sentinel nodes in patients with breast cancer. However, the mechanism of metastatic spreading of tumor cells to distant lymph nodes in patients with colorectal carcinoma is not fully understood. In this study, we investigated the factors that may determine the likelihood of additional regional lymph node metastasis when metastasis is found in nodes at the N1 site in colorectal cancer, especially focusing on the presence of ECI.MethodsTwo hundred and twenty-eight consecutive patients who underwent colorectal resection were identified for inclusion in this study, of which 37 (16.2%) had positive lymph nodes at the N1 site. Six of these 37 cases had additional metastasis in N2 site lymph nodes. We reviewed the clinicopathological features of these cases and performed statistical analysis of the data.ResultsIn the univariate analysis ECI at the N1 site was the only factor significantly associated with the presence of cancer cells in the N2 site. Other factors, including number of positive lymph nodes, lymphovascular invasion of the primary tumor, tumor size and tumor depth of invasion, were not associated with metastatic involvement at the N2 site.ConclusionsOur results suggest that the presence of ECI at metastatic lymph nodes at the N1 site is correlated with further metastasis at the N2 site. These findings imply the possibility that ECI might indicate the ability of colorectal tumor cells to disseminate to distant lymph nodes.

Extracapsular invasion as a risk factor for disease recurrence in colorectal cancer.

AIM To evaluate the presence of extracapsular invasion (ECI) in positive nodes as a predictor of disease recurrence disease in colorectal cancer. METHODS Two hundred and twenty-eight consecutive patients who underwent colorectal resection were identified for inclusion in this study, of which 46 had positive lymph nodes. Among 46 cases with stage IIIcolorectal cancer, 16 had ECI at positive nodes and 8 had disease recurrence. The clinical and pathological features of these cases were reviewed. RESULTS In the univariate analysis, the number of positive lymph nodes and depth of tumor invasion were significantly associated with the presence of ECI at positive nodes. Multivariate analysis demonstrated that only ECI was a predictor of recurrence. The recurrence-free interval differed significantly among patients with ECI at positive nodes. CONCLUSION Our results suggest that ECI at metastatic nodes can identify which cases are at high risk of short-term disease recurrence in colorectal cancer.

Correlation between colonic motility and defecatory disorders after anterior resection of the rectum in canine models

Abstract  The objective of this study was to describe the correlation between changes in colonic motility and defecatory disorders in four experimental canine models, with an emphasis on denervation. Therefore, we constructed a model by dividing 20 healthy mongrel dogs into four groups, i.e. control, denervation, transection and anterior resection of the rectum (AR) (denervation plus transection), and focused on the correlation between colonic motility and defecatory disorders by counting the colonic migrating motor complexes (CMMCs) and colonic non‐migrating motor complexes (CNMCs). Gastrointestinal and colonic contractile activities were continuously recorded on a computer with strain gauge force transducers. The dogs’ feces were checked daily, and their consistency was recorded as normal, semisolid, or watery. Compared with the control group, the transection group showed elongation of the propagation time (P < 0.05), and the mean motility index of colonic contractile activity at C4 and C5 in the denervation group was greater than that in the control group (P < 0.05). The AR group showed three features of colonic motility: (i) elongation of the mean CMMC cycle (P < 0.05); (ii) shortening of the propagation time (P < 0.05); and (iii) increment of the number of CNMCs. Concerning fecal consistency, the AR group only showed watery diarrhoea. In conclusion, we revealed the existence of a correlation between defecatory disorders and changes in colonic motility. Increased knowledge among colorectal surgeons of the changes in colonic motility that occur following colorectal surgery is very important and could lead to the curtailment of defecatory disorders among patients.

Ectopic Sebaceous Glands in the Esophagus: Endoscopic Findings over Three Years

Sebaceous glands in the esophagus are rare and are of particular interest because of their as yet unknown origin. We report a case with ectopic sebaceous glands diagnosed by esophageal endoscopy and biopsy, with follow-up endoscopic examinations for 3 years. Few cases with follow-up endoscopic findings have been reported. In our case, there were no significant overall changes during 3 years of follow-up, but the lesions fluctuated over time. While taking the endoscopic findings of the present or past cases into account, we discuss the possible pathogenic mechanisms of this condition.

A Case of Very Well-Differentiated Adenocarcinoma With Carcinoid Tumor in the Ascending Colon

Malignant tumors with mixed glandular and neuroendocrine characteristics with at least 30% of each component are classified as mixed adenoneuroendocrine carcinoma (MANEC) by the World Health Organization 2010 classification. We report here a case of very well-differentiated adenocarcinoma accompanied by carcinoid tumor, categorized as MANEC. A 41-year-old Japanese man was clinically diagnosed with ascending colon cancer and underwent right hemicolectomy. Using an immunohistologic technique, the pathologic diagnosis was very well-differentiated adenocarcinoma accompanied by carcinoid tumor and marked eosinophil infiltration, which was categorized as MANEC. By immunohistochemical analysis, tumor cells of the carcinoid component exhibited very low proliferation activity. Our case was thought to be MANEC without high malignant potential. MANEC as per the World Health Organization 2010 classification seems to include tumors with diverse grades of malignancy, and it might need to have subclassifications according to the malignancy potential of the tumor cells.

Adenocarcinoma of Ascending Colon Associated with Sarcoid Reaction in Regional Lymph Nodes.

Lymph node swelling in the setting of malignancy generally suggests metastasis of the primary tumor. A granulomatous reaction, i.e. sarcoid reaction, occurring within the lymph nodes draining carcinomas is a well-known but uncommon occurrence. The phenomenon is especially rarely seen in colon carcinoma. We herein report a rare case of a 56-year-old Japanese male with adenocarcinoma of the ascending colon associated with sarcoid reaction in the regional lymph nodes. A typical ileocecal resection and lymph node dissection were performed. Histopathological examination revealed moderately differentiated adenocarcinoma of the ascending colon, and the dissected lymph nodes included epithelioid granulomas with multinucleated giant cells. These findings suggest the existence of a sarcoid reaction associated with colon carcinoma; there was no metastasis in the dissected lymph nodes. The significance of this rare condition is discussed.

Elevated C-reactive protein is associated with the tumor depth of invasion but not with disease recurrence in stage II and III colorectal cancer.

BACKGROUND/AIMS We previously demonstrated that elevated serum C-reactive protein (CRP) level is associated with depth of tumor invasion in operable colorectal cancer. There is also increasing evidence to show that raised CRP concentration is associated with poor survival in patients with colorectal cancer. The purpose of this study was to investigate the correlation between preoperative CRP concentrations and short-term disease recurrence in cases with stage II and III colorectal cancer. METHODOLOGY Of the 224 cases with resected colorectal cancer, 55 patients with TNM stage II and 50 with stage III were analyzed in this study. The clinical features were reviewed according to the CRP level, and statistical analysis was performed. In cases with stage II and III, 11 and 6 of which had elevated serum CRP (>=10mg/L), respectively. Recurrence-free interval was defined as the interval from surgery to the time disease recurrence was diagnosed. Among the cases with stage II and III colorectal cancer, 4 and 10 had recurrent disease. RESULTS Among various clinicopathological characteristics, depth of tumor invasion was independently associated with preoperative elevation of CRP in stage II and III colorectal cancer in multivariate subgroup analysis. However, recurrence-free interval by Kaplan-Meier curves did not differ significantly among patients with preoperative CRP concentrations. CONCLUSIONS Our results suggest that elevated serum CRP level is associated with depth of tumor, but not with recurrent disease in stage II and III colorectal cancer.