Nobuo Murata

Pneumoperitoneum with carbon dioxide enhances liver metastases of cancer cells implanted into the portal vein in rabbits

AbstractBackground: Little is known about the role of the CO2 pneumoperitoneum on tumor cells that spread from the portal system into the liver during laparoscopic surgery for gastrointestinal malignancies. Therefore, we designed a study to investigate the effect of CO2 pneumoperitoneum on cancer cells implanted in the portal vein in a rabbit model. Methods: Immediately after intraportal inoculation of 2.5 × 105 cells of VX2 cancer, the rabbits received either CO2 pneumoperitoneum at a pressure of 10 mmHg for 30 min (pneumoperitoneum group, n= 14) or laparotomy alone for 30 min (laparotomy group, n= 14). Results: The number (p < 0.01) and area of cancer nodules (p= 0.045) on the liver surface on day 17 were greater in the pneumoperitoneum group than in the laparotomy group. The frequency of cancer nodules >3.0 mm in diameter was higher in the pneumoperitoneum group than in the laparotomy group (p < 0.001). Conclusions: Compared with laparotomy, CO2 pneumoperitoneum enhanced the development of liver metastases in this experimental model.

Influence of trocar placement and CO2 pneumoperitoneum on port site metastasis following laparoscopic tumor surgery

AbstractBackground: The mechanisms involved in the development of port site metastasis following laparoscopic tumor surgery remain controversial. Therefore, we decided to investigate the influence of trocar placement and CO2 pneumoperitoneum on abdominal wound implantation in relation to intraperitoneal tumor growth in a rabbit model. Methods: Rabbits received either CO2 pneumoperitoneum with insertion of nine trocars (pneumoperitoneum group, n= 15), insertion of nine trocars alone (nonpneumoperitoneum group, n= 15), or nine abdominal incisions (control group, n= 13) 3 days after intraperitoneal inoculation of VX2 cancer cells. Results: The frequency of overall wound implantation on day 17 in the pneumoperitoneum group (24.4%) and nonpneumoperitoneum group (27.4%) tended to be higher than that in the control group (15.3%) (p= 0.06). There was no significant difference among the three groups in the growth of cancer nodules on the omentum. Conclusions: The presence of a trocar may be a factor contributing to port site metastasis but CO2 pneumoperitoneum appears not to be a factor.

Serum Levels of Tissue Inhibitor of Metalloproteinases-1 (TIMP-1) in Colorectal Cancer Patients

PurposeExpression of tissue inhibitor of metalloproteinases (TIMP)-1 in colorectal cancer tissue is known to be related to disease progression; however, the clinical significance of measuring the blood level of TIMP-1, which we evaluate herein, has not yet been clarified.MethodsThe serum level of TIMP-1 was measured by a one-step enzyme immunoassay in 123 patients who underwent resection of primary colorectal cancer.ResultsAn elevated level of serum TIMP-1 was associated with advanced Dukes’ stage (P = 0.03), greater diameter of the primary tumor (P = 0.03), more lymph node metastasis (P = 0.04), and liver metastasis (P ≪ 0.001). There was a weakly positive correlation between the serum carcinoembryonic antigen (CEA) level and the serum TIMP-1 level. In patients who underwent potentially curative resection, the disease-free survival was not different between those with a high TIMP-1 level (≧203.5 ng/ml, n = 32) and those with a low TIMP-1 level (≪203.5 ng/ml, n = 66, P = 0.62). In patients with Dukes’ stage D cancer who underwent noncurative resection, the survival times were not different between those with a high TIMP-1 level (n = 13) and those with a low TIMP-1 level (n = 10, P = 0.20).ConclusionsElevated levels of serum TIMP-1 reflect the extent of colorectal cancer, without a close correlation with the serum CEA level. These findings suggest that measuring the serum TIMP-1 level would not help to predict the prognosis of patients with colorectal cancer.

Laparoscopic gastropexy for acute gastric volvulus: A case report

A 7-year-old girl presented with an acute gastric volvulus that was reduced with a nasogastric catheter. An anterior gastropexy was undertaken laparoscopically. The gastrocolic omentum was deficient along most of the greater curvature, which had allowed organoaxial volvulus. Two years later, gastric volvulus has not recurred. Laparoscopy is an acceptable approach for the evaluation and treatment of children with acute gastric volvulus.

Fulminant amoebic colitis with perforation successfully treated by staged surgery: a case report

Radical surgery for fulminant amoebic colitis leads to extremely high mortality; however, resective surgery is mandatory if a patient develops massive fecal peritonitis. We herein report an extremely rare case of fulminant amoebic colitis with multiple perforations, which was successfully treated by staged surgical procedures. A 48-year-old man who had been treated with predonisolone under a diagnosis of ulcerative colitis was admitted. Biopsy specimens from the colonic mucosa revealed Entamoeba histolytica. On the day of diagnosis, he developed severe abdominal pain and underwent emergency laparoptomy, showing total colonic gangrene with multiple perforations associated with massive fecal peritonitis. Subtotal colectomy, mucous fistula of the rectosigmoid, and ileostomy were performed. He recovered well although disseminated intravascular coagulopathy developed postoperatively. As the middle and upper part of rectum was found to be severely stenotic 4 months after surgery, we performed proctectomy, ileal pouch anal canal anastomosis, and diverting ileostomy, which was reversed 6 months later. The patient has been well with satisfactory anal function 37 months after the initial surgery. This case suggests that (1) early and accurate diagnosis of amoebiasis is important to avoid surgical intervention, and (2) staged surgery including total colectomy should be considered as one of the treatment choices even in patients with total necrotizing amoebic colitis.

Effect of CO2 Pneumoperitoneum on Growth of Liver Micrometastases in a Rabbit Model

Little is known about the risk of metachronous liver metastases following laparoscopic resection for gastrointestinal malignancies. The effect of CO2 pneumoperitoneum on the growth of established liver micrometastases was investigated in a rabbit model. Male Japanese white rabbits weighing 2.8 to 3.3 kg were randomized to three groups (n= 15 per group) 3 days following intraportal inoculation of a tumor suspension containing 5 × 104 cells of VX2 cancer. In the pneumoperitoneum group, insufflation with CO2 was maintained at a pressure of 10 mmHg for 30 minutes. In the laparotomy group the abdominal cavity remained open through a 45 mm midline incision for 30 minutes; in the control group no treatment other than anesthesia was performed. Cancer nodules on the liver surface were compared among the three groups on day 17. There was no difference in the number of cancer nodules among the groups (p= 0.72). A significant difference in the total area of cancer nodules (mean ± SEM) was found only between the pneumoperitoneum group (696.0 ± 177.0 mm2) and the control group (247.2 ± 60.7 mm2) (p < 0.05). The frequency of cancer nodules larger than 3.0 mm in maximal diameter tended to be highest in the pneumoperitoneum group (p= 0.053). These results suggests that CO2 pneumoperitoneum may promote the growth of established liver micrometastases in this animal model.

Increased insufflation pressure enhances the development of liver metastasis in a mouse laparoscopy model

Background: The effect of different insufflation pressures and durations of CO2 pneumoperitoneum on the growth of liver metastasis was investigated in a mouse model. The possible mechanisms involved in the pressure-related enhancement of liver metastasis were also examined. Methods: Mice inoculated intraportally with colon 26 cells underwent CO2 pneumoperitoneum at different pressures (5,10, or 15 mmHg) for 30 or 60 min, or received no treatment other than tumor cell inoculation (control). The subsequent growth of liver mestastases was examined. Mice injected intraportally with 111In-oxine-labeled colon 26 cells underwent pneumoperitoneum at three different pressures or served as controls. The radioacitivity of the liver was determined to evaluate tumor accumulation in the liver. Mice received pneumoperitoneum at three different pressures or received trocar placement alone. Changes in plasma interleukin-6 levels were determined. Results: The growth of liver metastases on day 14 was influenced by increased insufflation pressures (p < 0.05) rather than the prolonged duration of pneumoperitoneum without significant interaction. The 15-mmHg pneumoperitoneum group showed a higher (p < 0.05) accumulation of radioactivity in the liver compared with the 5-mmHg pneumoperitoneum group and controls. Pneumoperitoneum groups with 5 and 10 mmHg showed higher (p < 0.05) peak levels of IL-6 compared with controls. Conclusions: An elevated insufflation pressure plays an important role in the enhancement of liver metastases, and this pressure-related adverse effect may be partly relevant to facilitating accumulation of tumor cells in the liver.

Liver metastasis following pneumoperitoneum with different gases in a mouse model

BackgroundThe validity of using CO2 in laparoscopic tumor surgery has not yet been established. To address this question, we investigated the growth of liver metastases following insufflation with different gases in a mouse laparoscopy model.MethodsMale BALB/C mice inoculated intraportally with colon 26 cells were randomized to undergo pneumoperitoneum with CO2 (n=16), helium (n=16), argon (n=16), or air (n=17), or to act as controls without insufflation (n=17).ResultsThe growth of cancer nodules on the liver 14 days after surgery was greater in mice following insufflation with CO2 (p<0.01), helium (p<0.01), argon (p=0.01), and air (p=0.07) than in control mice. No significant differences were found between the four insufflation groups in the growth of liver metastases.ConclusionThese results suggest that insufflation plays an important role in the development of liver metastases but that the choice of gas may not affect their growth.

The influence of different insufflation pressures during carbon dioxide pneumoperitoneum on the development of pulmonary metastasis in a mouse model

AbstractBackground: The effects of different insufflation pressures on the development of pulmonary metastasis was investigated in a mouse laparoscopy model. Methods: BALB/C mice intravenously inoculated with colon 26 cells were randomized to one of five treatment groups (10 mice per group): pneumoperitoneum at different pressures of 5, 10 or 15 mmHg; full laparotomy for 60 min; or anesthesia control. Cancer nodules on the lung surface 19 days postoperatively were compared between groups. Results: (a) As compared with the control group, pneumoperitoneum at 10 and 15 mmHg and laparotomy enhanced the growth of pulmonary metastases (p < 0.01). (b) The growth of metastases also was greater in laparotomy group mice than in mice undergoing pneumoperitoneum at 5 and 10 mmHg (p < 0.05). Conclusions: These results suggest that the effects of different insufflation pressures on the growth of pulmonary metastases are not identical, and that pneumoperitoneum with high pressure may promote pulmonary metastases similar to those with laparotomy.

Influence of perioperative blood transfusion on the prognosis of patients with gastric cancer receiving anticancer chemotherapy.

AbstractBackground. The deleterious effect of blood transfusions on survival has been reported in patients with cancers of various organs. However, it remains unclear whether there is any adverse effect of blood transfusion when the patients are administered anticancer drugs after surgery for gastric cancers. Methods. Data from patients with gastric resection for advanced gastric cancer were retrospectively analyzed to determine the influence of perioperative blood transfusion on the survival rate. All patients were administered anticancer drugs (mitomycin C [MMC] and tegafur-uracil [UFT]). Sixty-nine (33%) of 208 patients received blood transfusion perioperatively, while 139 patients (67%) did not receive transfusion. Multivariate analysis of clinicopathologic prognostic factors, including blood transfusion, was performed. Lymphocyte subsets were measured to investigate the immunosuppressive effect of blood transfusion. Results. The 5-year survival rate was 48.8% in the 69 transfused patients and 66.9% in the 139 non-transfused patients (P < 0.01). Coxs multiple regression analysis showed that, when patients received anticancer drugs, perioperative blood transfusion was not a significant factor affecting survival after the gastric cancer surgery. However, the CD4/CD8 ratio at 3 months after the surgery was significantly lower in the transfused group than in the non-transfused group. Conclusion. Blood transfusion did not affect the survival of operated patients who received postoperative adjuvant chemotherapy. However, the finding that the ratio of CD4/CD8 after surgery was significantly higher in the non-transfused group than in the transfused group supports the notion that transfusion causes broad-spectrum immunosuppression.