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(1/2594) Classification of human colorectal adenocarcinoma cell lines.

Eleven human colorectal adenocarcinoma cell lines established in this laboratory were classified into three groups based on morphological features (light and electron microscopy), modal chromosome number, and ability to synthesize carcinoembryonic antigen (CEA). Group 1 cell lines contained both dedifferentiated and differentiating cells growing in tight clusters or islands of epithelium-like cells; their modal chromosome number was about 47, and they synthesized small to moderate amounts of CEA. Group 2 cell lines were more dedifferentiated, were hyperdiploid, and synthesized small amounts of CEA. Group 3 cell lines were morphologically similar to those of Group 1 by light microscopy. They differed ultrastructurally by containing microvesicular bodies; the modal chromosome number varied from hyperdiploid to hypertriploid or they had bimodal populations of hypodiploid and hypertriploid cells, and they synthesized relatively large amounts of CEA. No correlation could be found between Broder's grade or Duke's classification of the original tumor and modal chromosome number or ability to synthesize CEA. These findings support Nowell's hypothesis that the stem line is different for each solid tumor, which makes it difficult to relate chromosomal changes to the initiation of the neoplastic state.  (+info)

(2/2594) Incidence of rectosigmoid adenomatous polyps in subjects without prior colorectal adenoma or cancer: a prospective cohort study.

BACKGROUND: Subjects without known colorectal adenomas or cancer constitute a large majority of the population where 85% of all cases of colorectal cancer are thought to occur. Consequently these people should be considered for screening to decrease mortality from colorectal cancer in the general population. AIMS: To estimate the incidence rate of rectosigmoid adenomas in these subjects. METHODS: Subjects without adenomas or cancer at a previous examination which had visualised the rectosigmoid underwent a fibre endoscopy every three years. Endoscopic data and population characteristics were collected prospectively. RESULTS: A total of 450 subjects fulfilled the selection criteria; 287 (64%) underwent at least two examinations, and 163 had three or more. At the second examination, with a mean delay of 39 months, the incidence rate of rectosigmoid adenomas was 1.50% per patient year. The rate was 1.75% per patient year (95% CI 0.80-3.33) at the third endoscopy with an additional mean delay of 38 months. The cumulative incidence rate at six years was 7.3% (95% CI 4.3-10.3), representing a mean of 1.2% per patient year. This rate increased with age and was higher for men than for women after age adjustment (p< 0.03). CONCLUSIONS: The incidence rates are very low compared with those of patients with prior adenomas. These results should be considered in establishing rectosigmoid adenoma screening strategies.  (+info)

(3/2594) Evidence of improving survival of patients with rectal cancer in france: a population based study.

BACKGROUND: Over the past 20 years there have been many changes in the management of rectal cancer. Their impact on the overall population is not well known. AIMS: To determine trends in management and prognosis of rectal cancer in two French regions. SUBJECTS: 1978 patients with a rectal carcinoma diagnosed between 1978 and 1993. METHODS: Time trends in treatment, stage at diagnosis, operative mortality, and survival were studied on a four year basis. A non-conditional logistic regression was performed to obtain an odds ratio for each period adjusted for the other variables. To estimate the independent effect of the period a multivariate relative survival analysis was performed. RESULTS: Over the 16 year period resection rates increased from 66.0% to 80.1%; the increase was particularly noticeable for sphincter saving procedures (+30.6% per four years, p=0.03). The percentage of patients receiving adjuvant radiotherapy increased from 24.0% to 40.0% (p=0.02). The proportion of patients with Dukes' type A cancer increased from 17. 7% to 30.6% with a corresponding decrease in those with more advanced disease. Operative mortality decreased by 31.1% per four years (p=0.03). All these improvements have resulted in a dramatic increase in relative survival (from 35.4% for the 1978-1981 period to 57.0% for the 1985-1989 period). CONCLUSIONS: Substantial advances in the management of rectal cancer have been achieved, but there is evidence that further improvements can be made in order to increase survival.  (+info)

(4/2594) Loss of heterozygosity at 18q21 is indicative of recurrence and therefore poor prognosis in a subset of colorectal cancers.

Adjuvant therapies are increasingly used in colorectal cancers for the prevention of recurrence. These therapies have side-effects and should, thus, be used only if really beneficial. However, the development of recurrence cannot be predicted reliably at the moment of diagnosis, and targeting of adjuvant therapies is thus based only on the primary stage of the cancer. Loss of heterozygosity (LOH) in the long arm of chromosome 18 is suggested to be related to poor survival and possibly to the development of metastases. We studied the value of LOH at 18q21 as a marker of colorectal cancer prognosis, association with clinicopathological variables, tumour recurrence and survival of the patients. Of the 255 patients studied, 195 were informative as regards LOH status when analysed in primary colorectal cancer specimens using the polymerase chain reaction (PCR) and fragment analysis. LOH at 18q21 was significantly associated with the development of recurrence (P = 0.01) and indicated poor survival in patients of Dukes' classes B and C, in which most recurrences (82%) occurred. An increased rate of tumour recurrence is the reason for poor survival among patients with LOH at 18q21 in primary cancer. These patients are a possible target group for recurrence-preventing adjuvant therapies.  (+info)

(5/2594) Adjuvant therapy with oral fluoropyrimidines as main chemotherapeutic agents after curative resection for colorectal cancer: individual patient data meta-analysis of randomized trials.

BACKGROUND: Oral 5-fluorouracil and its prodrugs (tegafur, carmofur) is now being studied for adjuvant chemotherapy of curatively resected colorectal cancers. To evaluate the effect of these oral fluoropyrimidines (o-FPs), an individual patient data (IPD) meta-analysis of randomized clinical trials was performed in Japan as an inter-trialist group study. METHODS: Data from the three clinical trials in which postoperative adjuvant therapy with o-FPs was compared with surgery alone in patients with colorectal cancer were sought. IPD from a total of 4960 patients with follow-up periods of at least 5 years were analyzed. RESULTS: The results of the meta-analysis on an 'intention to treat' basis demonstrated a significant benefit of o-FPs in terms of the disease-free survival (DFS) of the total patients [risk ratio (RR) 0.830, 95% confidence interval (CI) 0.742-0.929, P = 0.001]. o-FPs were also demonstrated to be effective for survival in rectal cancer (RR 0.857, 95% CI 0.734-0.999, P = 0.049) and in Dukes'C colorectal cancer (RR 0.828, 95% CI 0.711-0.965, P = 0.016). CONCLUSION: The results suggest the advantage of long term o-FPs, possibly with the injection of mitomycin C, for prognosis for curatively resected colorectal cancer patients.  (+info)

(6/2594) Food groups and colorectal cancer risk.

Most studies of diet and colorectal cancer have considered nutrients and micronutrients, but the role of foods or food groups remains open to debate. To elucidate the issue, we examined data from a case-control study conducted between 1992 and 1997 in the Swiss canton of Vaud. Cases were 223 patients (142 men, 81 women) with incident, histologically confirmed colon (n= 119) or rectal (n= 104) cancer (median age 63 years), linked with the Cancer Registry of the Swiss Canton of Vaud, and controls were 491 subjects (211 men, 280 women, median age 58 years) admitted to the same university hospital for a wide spectrum of acute non-neoplastic conditions unrelated to long-term modifications of diet. Odds ratios (OR) were obtained after allowance for age, sex, education, smoking, alcohol, body mass index, physical activity and total energy intake. Significant associations were observed for refined grain (OR = 1.32 for an increase of one serving per day), and red meat (OR = 1.54), pork and processed meat (OR = 1.27), alcohol (OR = 1.28), and significant protections for whole grain (OR = 0.85), raw (OR = 0.85) and cooked vegetables (OR = 0.69), citrus (OR = 0.86) and other fruits (OR = 0.85), and for coffee (OR = 0.73). Garlic was also protective (OR = 0.32 for the highest tertile of intake). These findings in a central European population support the hypothesis that a diet rich in refined grains and red meat increases the risk of colorectal cancer; they, therefore, support the recommendation to substitute whole grains for refined grain, to limit meat intake, and to increase fruit and vegetable consumption.  (+info)

(7/2594) Serum YKL-40 and colorectal cancer.

YKL-40 is a mammalian member of the chitinase protein family. Although the function of YKL-40 is unknown, the pattern of its expression suggests a function in remodelling or degradation of extracellular matrix. High serum YKL-40 has been found in patients with recurrent breast cancer and has been related to short survival. In the present study we analysed YKL-40 in preoperative sera from patients with colorectal cancer and evaluated its relation to survival. Serum YKL-40 was determined by RIA in 603 patients. Survival after operation was registered, and median follow-up time was 61 months. Three hundred and forty patients died. Sixteen per cent of the patients with Dukes' A, 26% with Dukes' B, 19% with Dukes' C and 39% with Dukes' D had high serum YKL-40 levels (adjusted for age). Analysis of serum YKL-40 as a continuous variable showed an association between increased serum YKL-40 and short survival (P < 0.0001). Patients with high preoperative serum YKL-40 concentration had significantly shorter survival than patients with normal YKL-40 (HR = 1.7; 95% CI: 1.3-2.1, P < 0.0001). Multivariate Cox analysis including serum YKL-40, serum CEA, Dukes' stage, age and gender showed that high YKL-40 was an independent prognostic variable for short survival (HR = 1.4; 95% CI: 1.1-1.8, P = 0.007). These results suggest that YKL-40 may play an important role in tumour invasion.  (+info)

(8/2594) Laparoscopic resection does not adversely affect early survival curves in patients undergoing surgery for colorectal adenocarcinoma.

OBJECTIVE: To determine the survival curves for laparoscopic resection (LR) of colorectal cancer. SUMMARY BACKGROUND DATA: Laparoscopic resection for cure of colorectal cancer is controversial, and survival curves have not been determined. METHODS: A prospective database of 177 consecutive LRs of colorectal cancers performed between November 1991 and 1997 was reviewed. The TNM classification (stage 0, I, II, III, and IV) for colorectal cancers and the Kaplan-Meier method were used to determine survival curves. RESULTS: Of the 177 patients, 5 were excluded for not having adenocarcinomas. Twenty-five patients (14.5%) had conversion to open surgery; most of these patients had rectal cancer or tumor invasion to adjacent organs. Twelve patients were lost to follow-up. All 135 remaining patients had follow-up. Overall, 28 deaths occurred during the follow-up period, 15 of which were cancer-related. The median follow-up was 24 months for patients with stage I, II, and III disease and 9 months for patients with stage IV disease. Observed 2-year survival rates were 100% stage I, 88.7% stage II, 80.6% stage III, and 28.6% stage IV. Survival rates at 4 years were 100% stage I, 79.5% stage II, 53.7% stage III, and 0% stage IV. No trocar site recurrence was observed. CONCLUSIONS: Early survival curves for patients with colorectal cancer who underwent LR do not differ negatively from historical controls for conventional surgery. Further validation is needed.  (+info)