Increased peritoneal dissemination after laparotomy versus pneumoperitoneum in a mouse cecal cancer model

BACKGROUND

The effect of carbon dioxide (CO(2)) pneumoperitoneum on the liberation of cancer cells from the primary tumor is not clear. This study investigated the influence of laparotomy versus CO(2) pneumoperitoneum on the progression of colon cancer with serosal invasion in a mouse model.

METHODS

Pieces of human colon adenocarcinoma (HT29) tumor were implanted in the cecal wall of 45 BALB/c nude mice. Each mouse underwent one of three procedures: laparotomy, CO(2) pneumoperitoneum, or anesthesia (control). Three weeks later, the size and weight of cecal tumors, the number of nodules, and the tumor volume score of peritoneal dissemination were examined. Another 45 mice were treated in the same way. The cecal tumor was resected on days 1, 3, or 5 after treatment. Total RNA was isolated from the resected tumors. The expression of E-cadherin and beta-1 integrin messenger RNA (mRNA) was examined by semiquantitative real-time reverse transcriptase-polymerase chain reaction assay.

RESULTS

Significantly more nodules of peritoneal dissemination were found in the laparotomy group than in the control group (p < 0.05). The tumor volume score of peritoneal dissemination in the laparotomy group was significantly higher than in the other two groups (p < 0.05). The expression of E-cadherin mRNA at day 5 in the laparotomy group was significantly less than in the other two groups (p < 0.05). There were no differences in beta-1 integrin among three groups.

CONCLUSIONS

Peritoneal dissemination was more extensive after laparotomy than after CO(2) pneumoperitoneum in a mouse model of cecal cancer with serosal invasion. Decreased expression of E-cadherin mRNA in tumors after laparotomy, but not after CO(2) pneumoperitoneum, may be associated with the increase in peritoneal dissemination.

Laparoscopic versus conventional open resection of rectal carcinoma: A clinical comparative study

AIM: To evaluate the feasibility of laparoscopic resection of rectal carcinoma and to compare the short-term outcome of laparoscopic procedure with conventional open surgery for rectal cancer.

METHODS: Thirty-eight patients with rectal cancer were included in a prospective non-randomized study. The patients were assigned to laparoscopic (n = 18) or open (n = 18) colorectal resection. Case selection, surgical technique, and clinical and pathological results were reviewed.

RESULTS: The operative time was longer in laparoscopic resection group (LAP) than in open resection group (189 ± 18 min vs 146 ± 22 min, P < 0.05). Intraoperative blood loss and postoperative complications were less in LAP resection group than in open resection group. An earlier return of bowel motility was observed after laparoscopic surgery. The overall postoperative morbidity was 5.6% in the LAP resection group and 27.8% in open resection group (P < 0.05). No anastomotic leakage was found in both groups. The pathologic examination showed that the length of the resected specimen, the mean number of harvested lymph nodes in laparoscopic resection group were comparable to those in open resection group.

CONCLUSION: Laparoscopic total mesorectal excision (TME) for rectal cancer is a feasible but technically demanding procedure. The present study demonstrates the safety of the procedure, while oncologic results are comparable to the open surgery, with a favorable short-term outcome.

[Colorectal cancer: 74 patients treated by laparoscopic resection with a mean follow-up of 5 years]

OBJECTIVE

The aims of this study were to analyse the results and long term outcome in a prospective non randomised trial of 74 patients treated by laparoscopic colo-rectal resection for cancer, and to determine wether survival and recurrence are or are not compromised by an initial laparoscopic approach.

PATIENTS AND METHODS

Seventy-four patients with colo-rectal carcinoma were included in a prospective trial and treated by laparoscopic resection. All patients were reviewed at 1, 3, and 6 months interval. A median of 5 years follow up was available. Forty-eight patients (65%) had more than 3 years of follow up.

RESULTS

Six conversions (8.1%) were necessary: 2 for tumor invasion of adjacent organs, 2 for limited margin resection in lower rectal tumors, 1 for small bowel injury and 1 for obesity. After surgery, passing flatus occurred at 34.3 +/- 16.7 h and oral intake could be reinstaured at 42.6 +/- 22 h. Mean postoperative stay was 8.2 +/- 3.4 days. No death occurred. The overall morbidity was about 13.5%. The rate of late complications was 5.4%. Two port site metastasis (2.6%) were seen in locally advanced carcinoma. Recurrence rate at 5 years was 0% for Dukes A, 20% for Dukes B, 39.2% for Dukes C. Survival rate at 5 years was 100% for Dukes A, 80% for Dukes B, and 60.7% for Dukes C. These results are similar to those of conventional open surgery.

CONCLUSION

Laparoscopic colorectal resection for cancer can be performed safely, with a low morbidity and rare late complications. Long term follow up (5 years) assessment shows similar outcome compared with conventional surgery.

Laparoscopic Versus Open Surgery For Colorectal Carcinoma

The role of laparoscopic resection in the management of colorectal cancer is still unclear. It has been shown that laparoscopic colectomies can be accomplished with acceptable morbidity. Major concerns are port-site recurrences and neoplastic dissemination. The aims of this study were to compare perioperative results and long-term outcomes in a prospective, nonrandomized study of patients treated by laparoscopic versus open colorectal resection for cancer. In particular, the effects of an initial laparoscopic approach on survival and recurrence were examined. One hundred fifty-seven patients with colorectal carcinoma were included in the prospective trial: 74 underwent laparoscopic resection and 83 underwent conventional open surgery. The two groups were comparable in terms of characteristics, demographic data, stage of disease, and use of adjuvant or palliative chemoradiotherapy. All patients were observed at 1.3- and 6-month intervals. The median duration of follow-up was 60 months (range, 10-125 months). The mean operating time was significantly longer in the laparoscopic group. Six conversions (8.1%) were necessary. The passage of flatus and the restarting of oral intake (P = 0.0001) occurred earlier in the laparoscopic surgery group than in the open conventional surgery group. The mean postoperative stay was significantly shorter in the former group (P = 0.005), as was the length of the scar (P = 0.001). There were no deaths in either group. The overall morbidity was significantly lower (13% versus 33.7%; P = 0.001) in patients treated laparoscopically. No significant differences were observed between the groups in the length of specimens, the size of the tumor, or the number of nodes removed. Late complications were more frequent after open resection (12% versus 5.4%; P = 0.01). Two port-site metastases (2.6%) were seen in stage III and IV locally advanced carcinoma. There was no significant difference in recurrent disease between the groups (24.3% versus 25%) during the 60-month follow-up. Stage-for-stage comparisons showed that disease recurrence rates and crude death rates were comparable.

Plasma concentration of tissue inhibitor of matrix metalloproteinase 1 in patients with colorectal carcinoma

BACKGROUND

The expression of tissue inhibitor of matrix metalloproteinase (TIMP) 1 in tumour tissue from patients with colorectal carcinoma has been reported to be related to disease progression. However, the clinical significance of plasma TIMP-1 has not been fully elucidated.

METHODS

The plasma level of TIMP-1 protein was determined by enzyme-linked immunosorbent assay in samples from 54 patients who underwent resection of the primary tumour.

RESULTS

Plasma TIMP-1 levels were associated significantly with depth of invasion and metastasis to lymph nodes and liver. Circulating TIMP-1 levels were significantly higher in patients with serosal invasion, liver metastases and Dukes' stage C tumours. Using a cut-off value of 160 ng/ml, serosal invasion and Dukes' C stage could be predicted with an accuracy of 68.5 per cent. With a cut-off value of 170 ng/ml, metastasis to the lymph node and liver could be predicted with an accuracy of 66.7 and 70.4 per cent respectively. These values were greater than those for carcinoembryonic antigen and CA19-9.

CONCLUSION

These data suggest that the plasma concentration of TIMP-1 correlates with both invasion and metastasis in patients with colorectal carcinoma.

Laparoscopic colectomy for Dukes A colon cancer

The use of laparoscopic surgery to treat colon cancer has been well studied; however, the specific use of laparoscopic colectomy for Dukes A colon cancer has not been evaluated. The data of laparoscopic colectomy were compared with those of conventional open colectomy, and the surgical results of patients who underwent surgery for Dukes A colon cancer were evaluated. Between November 1993 and October 1997, 20 patients underwent laparoscopic colectomy for Dukes A colon cancer. Operation time, blood loss, first passage of flatus, day of resumption of oral intake, length of hospital stay after surgery, and number of dissected lymph nodes were compared between 20 patients who underwent laparoscopic colectomy and 23 patients who underwent conventional open colectomy for Dukes A colon cancer. In patients with laparoscopic colectomy, when compared with those with conventional open colectomy, mean blood loss was less (103 g vs. 318 g), flatus returned more quickly (3.5 days vs. 4.2 days), oral intake resumed earlier (3.7 days vs. 4.7 days), and postoperative hospital stay was shorter (16.4 days vs. 24.6 days). The mean number of dissected lymph nodes was not different between the two groups (9.2 vs. 9.2 for D2 dissection). No patient had port-site metastasis or recurrence during a follow-up period from 13 to 60 months (median, 38 months). Review of the literature and the authors' findings indicated that none of the 142 reported patients had port-site metastasis after laparoscopic colectomy for Dukes A colon cancer. The results indicate that laparoscopic colectomy is safe and useful when applied to patients with Dukes A colon cancer and performed carefully by trained surgeons.

Histopathologic criteria for local excision of colorectal cancer: multivariate analysis

BACKGROUND

Local treatment of colorectal cancer, including endoscopic removal of colonic polyps and transanal resection of rectal tumors, has become widely accepted. However, risk factors predicting the presence of lymph node metastasis have not been fully investigated. To determine the criteria for local excision of colorectal cancer, histopathologic factors independently predicting the lymph node metastasis were investigated.

METHODS

We performed a retrospective histopathologic study on 335 patients who underwent resection of colorectal cancer and dissection of regional lymph nodes between 1982 and 1996. Features of node-positive tumors (n = 150) were compared with those of node-negative tumors (n = 185), with special reference to the histopathologic findings of the resected tumor. Multivariate analysis was done using the stepwise logistic regression test.

RESULTS

Node-positive tumors, when compared with node-negative tumors, were characterized by tumor larger than 6 cm (42% vs. 22%), serosal invasion (88% vs. 56%), lymphatic invasion (32% vs. 5%), venous invasion (9% vs. 2%), and histology other than well-differentiated (66% vs. 29%). Multivariate analysis showed that factors independently associated with lymph node metastasis were serosal invasion, lymphatic invasion, and histologic type. When these three risk factors were negative, lymph node metastasis was rare (5%). When one, two, or three factors were positive, the frequency of lymph node metastasis was 38%, 66%, and 85%, respectively.

CONCLUSIONS

In colorectal cancer, factors independently associated with lymph node metastasis are serosal invasion, lymphatic invasion, and histologic type. When these three parameters are favorable, local treatment of colorectal cancer does not require additional lymph node dissection.