Masaru Yokoyama

Impact of Oral Antimicrobial Prophylaxis on Surgical Site Infection and Methicillin-Resistant Staphylococcus aureus Infection After Elective Colorectal Surgery. Results of a Prospective Randomized Trial

Abstract The impact of oral antimicrobial prophylaxis on the surgical site infection and methicillin-resistant Staphylococcus aureus (MRSA) infection after elective colorectal surgery was evaluated by a prospective randomized single-blind study. The patients were randomly allocated to receive either mechanical bowel cleansing with polyethylene glycol alone (group 1) or mechanical cleansing plus oral antimicrobial prophylaxis with kanamycin and erythromycin for 2 days prior to surgery (group 2). In both groups, cefotiam was intravenously given twice a day for 3 days. A total of 143 patients (71 for group 1 and 72 for group 2) were eligible. The incidence of a surgical site infection was 23.9% in group 1 and 11.1% in group 2 (P = 0.04). The incidence of MRSA infection including at surgical and remote sites was 11.1% in group 1 and 5.6% in group 2 (P = 0.19). A multivariate logistic regression analysis showed that the risk of surgical site infection was influenced by the choice of the chemical bowel preparation (P = 0.03) and blood loss (P < 0.01), while an MRSA infection was predominantly influenced by blood loss (P < 0.01) followed by coexisting underlying diseases (P = 0.07). These results suggest that preoperative antimicrobial prophylaxis would be useful for reducing the incidence of a surgical site infection without increasing the risk of an MRSA infection following elective colorectal surgery.

Short-term intravenous antimicrobial prophylaxis in combination with preoperative oral antibiotics on surgical site infection and methicillin-resistant Staphylococcus aureus infection in elective colon cancer surgery: Results of a prospective randomized trial

PurposeWe performed a prospective randomized study to assess the effectiveness of short-term intravenous antimicrobial prophylaxis in combination with preoperative oral antibiotics on a surgical site and methicillin-resistant Staphylococcus aureus (MRSA) infection in elective colon cancer surgery.MethodsThe patients were administered preoperative oral antibiotics, kanamycin and erythromycin, after mechanical cleansing, which began within 24 h of elective surgery for colon cancer. The patients were randomly assigned to receive the intravenous administration of cefmetazol or cefotiam on the day of surgery (group 1) or for 3 days (group 2). A total of 275 patients (136 for group 1 and 139 for group 2) were eligible for the study.ResultsThe incidence of a surgical site infection was 5.1% in group 1 and 6.5% in group 2 (P = 0.80). The incidence of MRSA infection was 2.2% in group 1 and 2.9% in group 2 (P > 0.99). A multivariate logistic regression analysis showed that the American Society of Anesthesiologists physical status score and the duration of surgery were independent significant factors affecting the surgical site infection and MRSA infection.ConclusionThese findings suggest that short-term intravenous antimicrobial prophylaxis in combination with preoperative oral antibiotics may be successfully applied to colon cancer surgery that is generally performed in Japan.

Minilaparotomy approach for colonic cancer: initial experience of 54 cases

BackgroundThe early outcomes of minilaparotomy for resection of colonic cancer were evaluated.MethodsIn this study, 54 patients (34 Dukes’ A, 15 Dukes’ B, and 5 Dukes’ C) successfully underwent curative resection of colonic cancer via minilaparotomy (skin incision, =7 cm). The major exclusion criteria for this approach required a body mass index greater than 25 kg/m2, a tumor size exceeding 7 cm, a preoperative ileus, and tumor invading the adjacent organs. Patients (n = 54) who had undergone conventional open surgery before the introduction of this technique served as the control group by matching several clinicopathologic factors including body mass index.ResultsThe passage of flatus (p < 0.01) and the beginning of oral intake (p = 0.02) were earlier, analgesic requirements were lower (p < 0.01), and postoperative serum C-reactive protein levels were lower in the minilaparotomy group (p < 0.01). The blood loss and frequency of postoperative complications did not differ between the groups.ConclusionA minilaparotomy approach is a feasible, minimally invasive, and attractive alternative to conventional laparotomy for selected patients with colonic cancer.

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.

Primitive neuroectodermal tumor arising in the colon: report of a case.

Peripheral primitive neuroectodermal tumors (pPNETs) are usually found in the soft tissue of the extremities, paravertebral region, and chest wall. We report a rare case of a pPNET arising in the colon. A 59-year-old man underwent left hemicolectomy for an infiltrative ulcerating tumor, 11 cm long, in the descending colon. Histological examination of the resected specimen revealed small, round cell proliferation with rosette-like structures, and confirmed regional lymph node involvement and peritoneal dissemination near the primary tumor. Immunohistochemically, the tumor cells were positive for synaptophysin and MIC2 (CD 99). ESW-FLI1 chimeric mRNA was detected in the tumor by reverse transcriptase–polymerase chain reaction. The patient underwent resection of recurrence in the retroperitoneum 3 months later, but metastasis rapidly developed and he died of the disease 7 months after his first operation.

Oncological effects of insufflation with different gases and a gasless procedure in rats.

Background: The validity of using carbon dioxide (CO2) pneumoperitoneum in laparoscopic tumor surgery has not been investigated thoroughly. The oncologic effects of a gasless procedure and insufflation with different gases were compared in rats. Methods: In all the experiments, Donryu rats were randomized to receive a gasless procedure; to receive insufflation with CO2, helium, or air at 10 mmHg for 30 min, or to serve as control subjects without insufflation. In experiment 1, involving 60 rats, ascites hepatoma AH130 cells were inoculated intraperitoneally just before the procedures. The S-phase fraction of the intraperitoneal tumor cells was determined using a flow cytometry on day 7. In experiment 2, 60 rats injected intraperitoneally with latex particles received one of the procedures. At the end of the procedure, peritoneal macrophages were harvested to determine the number of phagocytosed particles. In experiment 3, 75 rats inoculated intraperitoneally with AH130 cells received one of the procedures for 5 consecutive days and were followed for survival analysis. Results: Experiment 1: The S-phase fraction was lower after insufflation with air or helium (p < 0.01) than with the anesthesia control condition. Insufflation with CO2 showed a higher S-phase fraction than the gasless procedure or insufflation with air or helium ( p < 0.01). Experiment 2: The phagocytotic activity of peritoneal macrophages was increased by insufflation with helium and air, as compared with the control condition ( p < 0.01). Insufflation with CO2 deteriorated the phagocytotic activity more than the gasless procedure ( p < 0.05) or insufflation with air or helium ( p < 0.001). Experiment 3: Insufflation with gases demonstrated shorter survival than the anesthesia control condition or the gasless procedure regardless of the gases used (p < 0.01). Conclusions: These results suggest that the choice of gases may affect the proliferation of tumor cells and the phagocytotic activity of peritoneal macrophages, insufflation itself may promote tumor spread regardless of the gases used, and the gasless procedure may be oncologically advantageous in this animal model.

Liver metastases are less established after gasless laparoscopy than after carbon dioxide pneumoperitoneum and laparotomy in a mouse model

Background: Although the liver is the most frequent site of cancer recurrence after conventional open surgery for colorectal cancer, the effect of laparoscopic procedures with or without gas insufflation on the development of liver metastases is largely unknown. Methods: Male BALB/C mice inoculated intraportally with colon 26 cells were randomized to undergo carbon dioxide pneumoperitoneum (n = 14), abdominal wall lifting (n = 14), or full laparotomy (n = 12), or to serve as control subjects without any procedures other than tumor inoculation (n = 13). Results: The growth of liver metastases 14 days after surgery was enhanced after full laparotomy (p < 0.01) and pneumoperitoneum (p = 0.02), as compared with that in the control subjects, whereas there was no difference in the growth of liver metastases between abdominal wall lifting and the control condition (p = 0.99). Conclusions: These results suggest that the defense against liver metastasis is better preserved after the gasless procedure than after laparotomy and carbon dioxide pneumoperitoneum in the reported animal model.

Spermatic cord metastasis from colon cancer: Report of a case

We herein report an extremely rare case of a solitary metastasis to the spermatic cord from colon cancer. A 71-year-old man who had undergone a right hemicolectomy for stage II cecal cancer 12 months prior, and who had not received adjuvant chemotherapy, was found to have a mass in the right groin region. Computed tomography (CT) revealed that the right spermatic cord was involved in a heterogeneously enhanced mass that measured 37 mm in diameter. A right high orchiectomy was performed. Histological examination of the resected tumor revealed well-differentiated adenocarcinoma compatible with a metastasis from colon cancer. The patient has been doing well, without recurrence, for 15 months postoperatively. To our knowledge, this is the 9th case of a solitary metastasis to the spermatic cord from colon cancer to be reported in the Japanese literature. The survival data of the collected cases suggest that resection of the solitary metastasis to the spermatic cord from colon cancer improves the patient prognosis.

Incarcerated recurrent rectal prolapse with ileal strangulation: Report of a case

We report a rare case of incarcerated rectal prolapse with ileal strangulation occurring after a Gant-Miwa procedure with anal encircling (Thiersch’s procedure) for recurrent rectal prolapse. The patient was a 78-year-old woman who presented to our outpatient clinic the day after sudden rectal protrusion had occurred. She had undergone a Gant-Miwa procedure for rectal prolapse 4 years previously, and another Gant-Miwa procedure with anal encircling for recurrent rectal prolapse 18 months earlier. The patient attempted to reduce the prolapse manually, but was unsuccessful. On admission, a 10 × 4-cm semispherical mass was observed extra-anally, with a necrotic surface. We performed an emergency laparotomy, which rerealed a prolapse of the anterior wall of the rectum with part of the ileum protruding into the sac formation. Thus, we resected the incarcerated ileum followed by primary anastomosis and proctectomy (Hartmann’s procedure) with good results. This case demonstrates that ileal strangulation can occur as a complication of rectal prolapse recurrence after perineal repair.