Prophylactic portal infusion chemotherapy as adjuvant therapy for the prevention of metachronous liver metastasis in colorectal cancer

Adjuvant therapy for completely resected stage II colon cancer

BACKGROUND

Colon cancer is potentially curable by surgery. Although adjuvant chemotherapy benefits patients with stage III disease, there is uncertainty of such benefit in stage II colon cancer. A systematic review of the literature was performed to better define the potential benefits of adjuvant therapy for patients with stage II colon cancer.

OBJECTIVES

To determine the effects of adjuvant therapy on overall survival and disease-free survival in patients with stage II colon cancer.

SEARCH STRATEGY

Ovid MEDLINE (1986-2007), EMBASE (1980-2007), and EBM Reviews - Cochrane Central Register of Controlled Trials ( to 2007) were searched using the medical headings "colonic neoplasms", "colorectal neoplasms", "adjuvant chemotherapy", "adjuvant radiotherapy" and "immunotherapy", and the text words "colon cancer" and "colonic neoplasms". In addition, proceedings from the annual meetings of the American Society of Clinical Oncology and the European Society of Medical Oncology (1996 to 2004) as well as personal files were searched for additional information.

SELECTION CRITERIA

Randomized trials or meta-analyses containing data on stage II colon cancer patients undergoing adjuvant therapy versus surgery alone.

DATA COLLECTION AND ANALYSIS

:Three reviewers summarized the results of selected studies. The main outcomes of interest were overall and disease-free survival, however, data on toxicity and treatment delivery were also recorded.

MAIN RESULTS

With regards to the effect of adjuvant therapy on stage II colon cancer, the pooled relative risk ratio for overall survival was 0.96 (95% confidence interval 0.88, 1.05). With regards to disease-free survival, the pooled relative risk ratio was 0.83 (95% confidence interval 0.75, 0.92).

AUTHORS' CONCLUSIONS

Although there was no improvement in overall survival in the pooled analysis, we did find that disease-free survival in patients with stage II colon cancer was significantly better with the use of adjuvant therapy. It seems reasonable to discuss the benefits of adjuvant systemic chemotherapy with those stage II patients who have high risk features, including obstruction, perforation, inadequate lymph node sampling or T4 disease. The co-morbidities and likelihood of tolerating adjuvant systemic chemotherapy should be considered as well. There exists a need to further define which high-risk features in stage II colon cancer patients should be used to select patients for adjuvant therapy. Also, researchers must continue to search for other therapies which might be more effective, shorter in duration and less toxic than those available today.

Reduced E-cadherin expression and enlargement of cancer nuclei strongly correlate with hematogenic metastasis in colorectal adenocarcinoma

BACKGROUND

Synchronous and metachronous hematogenic metastases are frequently detected in patients with colorectal carcinoma. Once these metastases have developed, the prognoses of patients are poor. Previously, we reported that enlargement of cancer nuclei significantly correlated with metastatic potential of gastric cancer and hepatocellular carcinoma. Moreover, recently it has been reported that reduced expression of E-cadherin is associated with tumor metastasis. To evaluate the correlation between nuclear area (NA) of cancer cells and expression of E-cadherin, and to elucidate whether these factors correlate with clinical outcome in patients with colorectal carcinoma, 105 consecutive patients were investigated.

METHODS

In each case, the NAs of 600 cancer nuclei were analyzed by means of a computer-assisted image analysis system and E-cadherin expression was detected immunohistochemically by an anti-E-cadherin monoclonal antibody. The expression levels of E-cadherin were divided into three groups according to the percentages of E-cadherin-positive cells (level 0: positive cells < or = 50%, level 1: 50% < positive cells < or = 80%, level 2: positive cells > 80%).

RESULTS

The mean NA of cancer cells in 105 tumors was 57 microm2. The NAs of cancer cells enlarged in proportion to the decrease of E-cadherin expression levels (level 0, n = 48, 62 microm2; level 1, n = 35, 57 microm2, level 2, n = 22, 46 microm2, P = 0.002). The 10-year survival rates decreased in proportion to the reduced E-cadherin expression levels (80% in level 2, 64% in level 1, and 42% in level 0, P = 0.004). Moreover, the 10-year survival rate of 54 patients with large NA tumors (< or = 54 microm2, 36%) was significantly poorer than that of 51 patients with small NA tumors (< 54 microm2, 80%, P < 0.001). The NA of cancer cells was recognized as an important predictor for prognosis and hematogenic metastasis. Although reduced E-cadherin expression was not recognized as the risk factor for hematogenic metastasis, 80% of patients who developed hematogenic metastasis had tumors with both enlarged cancer nuclei and reduced E-cadherin expression.

CONCLUSIONS

Detection of NA of cancer cells and E-cadherin expression in patients with colorectal carcinoma may reveal important information for hematogenic metastasis.

Computerized nuclear morphometry is a useful technique for evaluating the high metastatic potential of colorectal adenocarcinoma

BACKGROUND

Nuclear profiles have been reported to be useful prognostic predictors in various cancers. Data from computerized morphometry are objective and are quickly obtained by conventional microscopic analysis. However, this image analysis of nuclear features has been only rarely applied to investigations of colorectal adenocarcinoma. The aim of this study was to evaluate the correlation between the morphologic nuclear features and clinicopathologic parameters in cases of colorectal adenocarcinoma.

METHODS

Morphometric nuclear features (nuclear area, perimeter, and shape) were analyzed in 343 patients with colorectal carcinoma and in 57 patients with colorectal adenoma. In each case, 300 nuclei of carcinoma or adenoma cells were analyzed on routine hematoxylin and eosin stained slides by means of a computer-assisted image analysis system that involved tracing the nuclear profiles (magnification x400) on a computer monitor. The morphometric data were compared with patients' survival, clinicopathologic status, and DNA ploidy pattern of tumors.

RESULTS

The mean nuclear area (NA) enlarged from normal colorectal mucosa to adenoma and carcinoma (normal mucosa: n = 343, mean NA = 19 micrometer(2); adenoma: n = 57, mean NA = 34 micrometer(2); mucosal carcinoma: n = 15, mean NA = 45 micrometer(2); P < 0.001). In 343 colorectal carcinomas, NAs of cancer cells in tumors with lymphatic invasion, venous invasion, lymph node metastasis, or hepatic metastasis were significantly larger than those of cancer cells in tumors without such factors. The mean NA of DNA aneuploid tumors was larger than that of DNA diploid tumors (P < 0.001). The nuclear area of cancer cells was determined to be one of the independent prognostic factors in multivariate analysis (P < 0.001). Moreover, the large nuclear area of cancer cells was recognized as one of the risk factors of metachronous hematogenic metastasis in patients after curative surgery.

CONCLUSIONS

Data from computerized morphometry are objective and can be obtained rapidly by conventional microscopic analysis. The nuclear area of cancer cells appears to predict 1) the ability of cancer cells to invade the microvessels in the colorectal wall and 2) the ability of cancer cells to metastasize to the lymph nodes or liver. Therefore, nuclear morphometry is beneficial in mass screening to select patients who are at risk of hematogenic or lymph node metastatic recurrence after curative surgery for colorectal carcinoma.

Flow cytometric examination of p53 protein in primary tumors and metastases to the liver and lymph nodes of colorectal cancer

PURPOSE AND METHODS

To confirm prognostic significance of overexpression of p53 in cases of colorectal cancer, expression of p53 protein was examined by flow cytometry in 113 cases of colorectal cancer and its metastasis to the liver and lymph nodes.

RESULTS

Overexpression of p53 was found in 44 (39 percent) of the 113 primary tumors. There were no significant correlations among the level of p53 protein in the primary tumor, clinicopathologic features, and prognosis of colorectal cancer. Overexpression of p53 protein was detected in 72 percent (18/25) of liver metastases and in 40 percent (10/25) of lymph node metastases. Frequency of samples that were positive for p53 was significantly higher for liver metastases than for primary tumors and lymph node metastases (P < 0.01). By comparing overexpression of p53 in primary tumors with that in corresponding secondary tumors, a decrease of more than 5 percent in the fluorescence index, compared with primary tumor, was not found in liver metastasis but was found in 20 percent of lymph node metastases. Incidence of cases with lower level expression of p53, compared with primary tumor, was significantly higher in lymph node metastases (32 percent) than in liver metastases (8 percent; P < 0.05).

CONCLUSIONS

From these results, it seems possible that overexpression of p53 may not be a good prognostic indicator of colorectal cancer and may be influenced by environments of the tumor.