Yasuo Kawaguchi

Single-port laparoscopic colectomy versus conventional laparoscopic colectomy for colon cancer: a comparison of surgical results

BackgroundSingle-port laparoscopic surgery is a new technique that leaves no visible scar. This new technique has generated strong interest among surgeons worldwide. However, single-port laparoscopic colon surgery has not yet been standardized. Our aim in this study was to evaluate the feasibility of single-port laparoscopic colectomy compared with conventional laparoscopic colectomy for colon cancer.MethodsWe conducted a case-matched, controlled study comparing single-port laparoscopic colectomy to conventional laparoscopic colectomy for right-sided colon cancer.ResultsA total of ten patients were included for the single-port laparoscopic colectomy (S-LAC) group and ten patients for the conventional laparoscopic colectomy (C-LAC) group. The length of the skin incision in the S-LAC group was significantly shorter than that of the C-LAC group.ConclusionOur early experiences indicated that S-LAC for right-sided colon cancer is a feasible and safe procedure and that S-LAC results in a better cosmetic outcome.

CDX2 Regulates Multidrug Resistance 1 Gene Expression in Malignant Intestinal Epithelium

The caudal-related homeobox transcription factor CDX2 has a key role in intestinal development and differentiation. CDX2 heterozygous mutant mice develop colonic polyps, and loss of CDX2 expression is seen in a subset of colon carcinomas in humans. Ectopic CDX2 expression in the stomach of transgenic mice promotes intestinal metaplasia, and CDX2 expression is frequently detected in intestinal metaplasia in the stomach and esophagus. We sought to define CDX2-regulated genes to enhance knowledge of CDX2 function. HT-29 colorectal cancer cells have minimal endogenous CDX2 expression, and HT-29 cells with ectopic CDX2 expression were generated. Microarray-based gene expression studies revealed that the Multidrug Resistance 1 (MDR1/P-glycoprotein/ABCB1) gene was activated by CDX2. Evidence that the MDR1 gene was a direct transcriptional target of CDX2 was obtained, including analyses with MDR1 reporter gene constructs and chromatin immunoprecipitation assays. RNA interference-mediated inhibition of CDX2 decreased endogenous MDR1 expression. In various colorectal cancer cell lines and human tissues, endogenous MDR1 expression was well correlated to CDX2 expression. Overexpression of CDX2 in HT-29 cells revealed increased resistance to the known substrate of MDR1, vincristine and paclitaxel, which was reversed by an MDR1 inhibitor, verapamil. These data indicate that CDX2 directly regulates MDR1 gene expression through binding to elements in the promoter region. Thus, CDX2 is probably important for basal expression of MDR1, regulating drug excretion and absorption in the lower gastrointestinal tract, as well as for multidrug resistance to chemotherapy reagent in CDX2-positive gastrointestinal cancers.

Primary lung cancer presenting with metastasis to the colon: a case report

Although about 50% of lung cancers have distant metastasis at the time of initial diagnosis, colonic metastases are extremely rare. This report presents a rare clinical case of colonic metastasis from primary squamous cell carcinoma of the lung.A 60-year-old female with anorexia and fatigue was referred to the department of pulmonary surgery in our hospital. The patient was diagnosed with primary squamous cell carcinoma of the lung, T2b N3 M1b Stage IV, and chemoradiotherapy was initiated. This treatment led to a good partial response in the primary lung lesion without any new metastatic lesions.The patient developed left abdominal pain due to a bulky sigmoid colon tumor 6 months later, and was preoperatively diagnosed with primary colon cancer. She underwent colonic resection, and the pathology specimen demonstrated poorly differentiated squamous cell carcinoma that was suspected to be colonic metastasis from the primary lung cancer. The postoperative course was uneventful, and she was discharged. Chemotherapy for the lung cancer was scheduled in the department of pulmonary surgery.This report presented a rare case of colonic metastasis from lung cancer. When patients with advanced primary lung cancer complain of abdominal symptoms, we should consider gastrointestinal tract metastasis from lung cancer.

Retroperitoneal abscess complicated with necrotizing fasciitis of the thigh in a patient with sigmoid colon cancer

BackgroundNecrotizing fasciitis of the thigh due to the colon cancer, especially during chemotherepy, has not been previously reported.Case presentationA 67-year-old man admitted to the hospital was diagnosed with sigmoid colon cancer that had spread to the left psoas muscle. Multiple hepatic metastases were also found, and combination chemotherapy with irinotecan and S-1 was administered. Four months after the initiation of chemotherapy, the patient developed gait disturbance and high fever and was therefore admitted to the emergency department of our hospital. Blood examination revealed generalized inflammation with a high C-reactive protein level. Computed tomography of the abdomen and pelvis showed gas and fluid collection in the retroperitoneum adjacent to the sigmoid colon cancer. The abscess was locally drained under computed tomographic guidance; however, the infection continued to spread and necrotizing fasciitis developed. Consequently, emergent debridement was performed. The patient recovered well, and the primary tumor was resected after remission of the local inflammation.ConclusionNecrotizing fasciitis of the thigh due to the spread of sigmoid colon cancer is unusual, but this fatal complication should be considered during chemotherapy for patients with unresectable colorectal cancer.

Preservation of peritoneal fibrinolysis owing to decreased transcription of plasminogen activator inhibitor-1 in peritoneal mesothelial cells suppresses postoperative adhesion formation in laparoscopic surgery

BACKGROUND Postoperative adhesion formation is regulated by peritoneal fibrinolysis, which is determined by tissue-type plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1). This study compared peritoneal fibrinolysis and adhesion formation after laparoscopic surgery (LAP) and open surgery (OP). METHODS We divided 154 male rats into 3 groups after cecal cauterization: Control, no treatment; LAP, CO2 pneumoperitoneum at 5 mmHg for 60 minutes; and OP, laparotomy for 60 minutes. Adhesions were quantified at day 7. The activity and mRNA level of tPA and PAI-1 were determined by enzyme-linked immunosorbent assay in plasma and peritoneal lavage and by real-time polymerase chain reaction in peritoneal mesothelial cells from omentum. We also examined peritoneal fibrinolysis in human gastric cancer patients treated with LAP (n = 14) or OP (n = 10). RESULTS In the animal study, adhesion scores, PAI-1 activity in peritoneal lavage fluid, and PAI-1 mRNA levels in peritoneal mesothelium were significantly greater in the OP group than the control and LAP groups. In the human study, postoperative PAI-1 mRNA levels were significantly greater in the OP group than the LAP group. Additionally, PAI-1 mRNA levels and subsequent adhesion formation were induced by prolonged operative time in the OP group, but not the LAP group. CONCLUSION Preservation of peritoneal fibrinolysis owing to decreased PAI-1 expression at the transcriptional level in peritoneal mesothelial cells is associated with suppression of postoperative adhesion formation in LAP. PAI-1 mRNA levels and subsequent adhesion formation were not induced by prolonged operative time in LAP. These results highlight the less invasiveness nature of LAP.

Adequate lymph node examination is essential to ensure the prognostic value of the lymph node ratio in patients with stage III colorectal cancer

PurposeThis study aimed to assess the prognostic value of the lymph node ratio (LNR), estimated by dividing the number of positive lymph nodes (LNs) by the number of LNs examined, for stage III colorectal cancer in comparison to the new tumor, nodes, and metastasis (TNM) system, and to evaluate the relationship between the number of LNs examined and the prognostic value of the LNR.MethodsWe retrospectively reviewed the clinicopathological data of a cohort of 266 patients with stage III colorectal cancer. We assessed the impact of LNR on the prediction of cancer recurrence in comparison to the TNM system, as well as the prognostic value of LNR in patients with a low LN count.ResultsIn multivariate analysis, the LNR was found to be an independent risk factor of cancer recurrence. The application of the LNR, in addition to the new TNM system, was more predictive of survival than the TNM system alone. A prognostic separation by LNR was observed in patients who had an adequate number of LNs examined, but not in patients with a low LN count.ConclusionsA stronger prognostic separation can be obtained by using the LNR together with the new TNM system. Adequate lymph node examination is important to ensure the prognostic value of LNR in patients with stage III colorectal cancer.

Chlorinated Water Modulates the Development of Colorectal Tumors with Chromosomal Instability and Gut Microbiota in Apc-Deficient Mice

The gastrointestinal tract is continuously exposed to a variety of chemicals and commensal bacteria. Recent studies have shown that changes in gut microbial populations caused by chlorine or other chemicals in the drinking water influence the development of human colorectal cancer, although the mechanism of tumorigenesis in the gut epithelium is obfuscated by the diversity of microflora and complexity of the tumor microenvironment. In this regard, mouse models that recapitulate human colorectal cancer are an invaluable tool. In this study, we used two conditional adenomatous polyposis coli (Apc) knockout mouse models to investigate the effect of chlorinated water on tumorigenesis in the digestive tract. Mice with colon-specific carcinoma—caused by either chromosomal (CDX2P 9.5-NLS Cre;Apc+/flox, abbreviated to CPC;Apc) or microsatellite (CDX2P9.5-G19Cre;Apcflox/flox and CDX2P9.5-G22Cre;Apcflox/flox) instability, respectively—were administered chlorinated (10.0 mg/L chlorine) or tap (0.7 mg/L chlorine) water and evaluated for colon polyp formation. In CPC;Apc mice given chlorinated drinking water, tumors tended to develop in the colon, whereas in those that drank tap water, tumors were mostly observed in the small intestine. There was no difference in the rate of tumor formation of CDX2P9.5-G19Cre;Apcflox/flox and CDX2P9.5-G22Cre;Apcflox/flox mice consuming chlorinated as compared to tap water, suggesting that microsatellite instability in the Apc gene does not significantly affect tumorigenesis. Chlorinated water altered the enteric environment by reducing the fecal populations of the obligatory anaerobes Clostridium perfringens and C. difficile, as well as species belonging to the Atopobium cluster, including Enterobacteriaceae and Staphylococcus sp., which was associated with colon tumorigenesis in CPC;Apc mice. These results suggest that differences in tumorigenesis among CPC;Apc mice consuming chlorinated versus tap water may be due to differences in gastrointestinal commensal populations.

Malignant peripheral nerve sheath tumor arising from the greater omentum: Case report

Malignant peripheral nerve sheath tumors (MPNSTs) are rare soft tissue tumors that arise from a peripheral nerve or exhibit nerve sheath differentiation. Most of these tumors arise on the trunk, extremities, or head and neck regions; they are very rarely located in the abdominal cavity. The patient was a 71-year-old man who was referred to our hospital for a mass and pain in the right lower abdomen. Abdominal computed tomography revealed a large (9 × 9 cm), well-circumscribed, lobulated, heterogeneously enhanced mass in the pelvis. Exploratory laparotomy revealed a large mass in the greater omentum, and the tumor was completely excised. Histopathological analysis revealed that the tumor was composed of spindle cells with high mitotic activity. On staining the tumor, positive results were obtained for S-100 but negative results were obtained for c-kit, cluster of differentiation (CD)34, α-smooth muscle actin, and desmin. These findings strongly supported a diagnosis of MPNST primarily arising from the greater omentum. To the best of our knowledge, this is the first reported case of an MPNST arising from the greater omentum. In this report, we have described the case of a patient with an MPNST arising from the greater omentum and have discussed the clinical characteristics and management of MPNSTs.

Single-Incision Laparoscopic Colectomy Using the Gelport System for Early Colon Cancer

Background Laparoscopic surgery has spread quickly during the past twenty years, and has become one of the important treatments in the field of colorectal surgery. Recently, natural orifice transluminal endoscopic surgery (NOTES) has been studied as the next generation of minimally-invasive surgery, but the feasibility and safety of the NOTES method have not been evaluated. In such a situation, single-incision laparoscopic surgery has attracted interest from surgeons worldwide. However, single-incision laparoscopic colorectal surgery has not yet been standardized. Methods From February 2010, single-incision laparoscopic colectomy was performed for 7 patients presenting with early colon cancer. All procedures were performed by two experts with the License of Endoscopic Surgical Skill Qualification System (ESSQS) of Japan Society for Endoscopic Surgery (JSES) in the field of colorectal Surgery. Results We used the Gelport system (Applied Medical, Rancho Santa Margarita, CA, USA) as the access port and 3 trocars of different sizes (Ethicon, Inc., Cincinnati, OH, USA). Using this technique, we did not experience any difficulties or use any articulated instruments. All of the present 7 patients underwent the single-incision laparoscopic colectomy successfully and had no complications. Conclusion: Single-incision laparoscopic surgery using the Gelport was performed safely in the present cases. The use of the Gelport as an access port can address the technical difficulty associated with this new technique.

Identification of patients likely to benefit from metastasectomy in stage IV colorectal cancer.

PurposeThe aim of the present study was to determine selection criteria for patients with stage IV colorectal cancer (CRC) who were likely to show survival benefits of metastasectomy.MethodsClinicopathological data of 119 patients with stage IV CRC who underwent primary CRC resection were retrospectively reviewed. The prognostic factors were analyzed according to the disease resectability status, and patients likely to show survival benefits of metastasectomy were identified.ResultsMetastasectomy was performed in 63 patients. Among these patients, R0 resection was reported in 55 patients, who comprised the curable group. The other 64 patients comprised the noncurable group. For the noncurable group, postoperative chemotherapy was identified as the only significant prognostic factor. In the curable group, T stage, histological type, elevated serum carcinoembryonic antigen (CEA) level and the presence of extra hepatic disease were identified as independent prognostic factors. Patients within the curable group were further classified into a low-risk group (zero to two prognostic factors) and a high-risk group (three or more prognostic factors). The overall survival (OS) of the high risk patients in the curable group was as poor as that of the patients in the noncurable group.ConclusionsStage IV CRC patients consisted of heterogeneous populations who had different prognostic factors, stratified by the disease resectability status. No prognostic benefit of metastasectomy was observed in high-risk patients undergoing curative metastasectomy. These results suggested that patients showing survival benefits of metastasectomy can be identified by considering the prognostic factors in patients undergoing curative metastasectomy.