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PubMed1998

Coexpression of MUC1 mucin peptide core and the Thomsen-Friedenreich antigen in colorectal neoplasms.

BACKGROUND: Controversial findings have been reported regarding the expression of the Thomsen-Friedenreich (TF) antigen in colorectal neoplasms when different monoclonal antibodies (MoAbs) have been used. Moreover, there is no information available regarding the carrier protein(s) of this antigen. METHODS: Forty-five colorectal adenomas and 48 carcinomas were studied by avidin-biotin complex-peroxidase immunohistochemistry. The immunohistochemistry employed the MoAb BW835, which was reactive to a carrier specific and site specific TF antigen on MUC1 mucin, as well as reference antibodies directed to MUC1 (HMFG2) or MUC2 core peptides (4F1) and directed to TF antigen irrespective of its carrier (A78-G/A7, peanut agglutinin). To evaluate the coexpression of different epitopes by the same antigen, sandwich enzyme-linked immunoadsorbent assays were performed. RESULTS: Although MUC1 peptide antigen and MUC1-bound TF antigen were not detectable in normal or transitional mucosa surrounding colorectal neoplasms, expression of these antigens in adenomas accompanied the development of high grade dysplasia. By contrast, MUC2 expression detected by the MoAb 4F1 was inversely correlated with the progression of the adenoma-carcinoma sequence. In well- and moderately differentiated colorectal carcinomas, the neo-expressed TF antigen is predominantly bound to MUC1. This feature could be demonstrated by antigen coexpression using peptide and the TF antigen specific MoAbs. However, in mucinous carcinomas exhibiting a weak MUC1 peptide expression in most specimens, the presence of TF antigen on the MUC2 peptide core cannot be ruled out. CONCLUSIONS: TF antigen is strongly coexpressed with MUC1 mucin peptide core in the colorectal adenoma-carcinoma sequence, resulting in well- and moderately differentiated carcinomas. Only in mucinous carcinomas may it be coexpressed with MUC2 antigen.

Adenocarcinoma↗
PubMed1996

Ki-67 and p53 immunoreactive stain and early colorectal neoplasms.

The aim of this work was to conduct a histopathological study of the different pathways of colorectal tumorigenesis by using Ki-67 and p53 immunoreactive stains. Between 1987 and 1993, 14,023 patients were investigated by colonoscopy at Akita Red Cross Hospital and several affiliated hospitals. Five hundred and sixty-five cases of early colorectal neoplasms identified in this population were used in the present study. Specimens were cut in half: one half was cut along the vertical axis, the other half along the horizontal axis to analyze the structure of glands which opened to the surface. They were stained with hematoxylin-eosin, Ki-67 and p53 immunoreactive stains. macroscopically, early colorectal neoplasms were classified into two types: protruding type and depressed type. The protruding type was mainly composed of branching glands. In contrast, the depressed type was almost completely composed of straight glands which opened to the surface. The Ki-67 positive ratio was almost equal. However, the p53 positive ratio was significantly different in the protruding type and the depressed type. The results suggest the existence of at least two pathways of colorectal tumorigenesis: one with the process of branching structure and one without the process of branching structure. Furthermore, there were clinical and immunohistochemical indications that the depressed type invades into deeper layers more rapidly than does the protruding type.

Adolescent↗
PubMed2006

The high prevalence of colorectal neoplasms in preoperative patients with abdominal aortic aneurysm or peripheral artery disease.

OBJECTIVE: In Japan, the incidence of both colorectal carcinoma and vascular disease is increasing. We screened preoperative patients with abdominal aortic aneurysm (AAA) or peripheral artery disease (PAD) for colorectal cancer. DESIGN OF STUDY: This study was retrospective and cross-sectional. MATERIALS: The subjects were 492 patients admitted for elective surgery of AAA or PAD. METHODS: The patients underwent immunochemical faecal occult blood tests (FOBT) before operation, and those with positive results underwent investigations for colorectal neoplasm. We compared the results with that of screening programmes performed on the general population. RESULTS: Of the 408 patients that underwent FOBT, 104 (25.5%) were positive. After colonoscopy, six (1.5%) had colorectal carcinoma and 16 (3.9%) had advanced adenoma. These values were several folds higher than that for the general population in Japan. CONCLUSIONS: Patients with AAA or PAD carry a high risk for colorectal neoplasm.

Aged↗
PubMed1995

Flow cytometric analysis of DNA synthetic phase fraction of the normal appearing colonic mucosa in patients with colorectal neoplasms.

DNA synthetic (S) phase fractions of normal appearing colonic mucosa in Japanese and British patients with colorectal neoplasms were compared with those in patients without colonic neoplasms. Normal crypts were isolated from fresh surgical specimens of the large intestine by the use of EDTA. After fixation with 70% ethanol, isolated crypts were digested with pepsin into single nuclei suspensions. These were stained with propidium iodide and examined by flow cytometry. S phase fraction was calculated from the flow cytometry DNA histogram using Baisch's method. S phase fractions of normal appearing crypts in Japanese and British patients with colorectal tumours were not significantly different and analysed together. S phase fraction of normal appearing colonic crypts in 14 patients with familial adenomatous polyposis (FAP) was 10.23 (2.59%) (mean SD)) ranging from 5.8 to 18.8. S phase fraction of background normal mucosal in patients with large adenomas (over 2 cm) and adenocarcinomas were 9.74 (3.76%) (range, 2.7-16.1) and 8.93 (3.54%) (range, 2.9-18.9) respectively. In normal mucosa of patients without any colorectal neoplasms, S phase fraction was 8.99 (3.94)% (range, 3.9-17.7). There was no statistically significant difference in S phase fractions of normal mucosa in the four groups. Our results show that an increase in proliferative activity of background colonic crypts is not necessary for tumour development.

Adenocarcinoma↗
PubMed1989

Fiberoptic sigmoidoscopy as the first screening procedure for colorectal neoplasms in an asymptomatic population.

As the first screening for colorectal neoplasms, a total of 2243 examinations by fiberoptic sigmoidoscopy (FS) were performed on 1573 asymptomatic patients. One hundred seventy neoplasms were found in 134 patients (6 percent of total examinations), including nine adenocarcinomas (0.4 percent). A flat, intramucosal cancer and a small, 5-mm cancer detected by FS could not be demonstrated by barium enema examination. On further investigation, additional adenomas were identified in the proximal colon in 22 percent of patients in whom neoplasms had first been detected by FS and in only 4.4 percent of those in whom FS findings were negative but other criteria were positive. It is concluded that FS is the procedure of choice for the first screening of asymptomatic patients, not only because it enables detection of flat and small lesions within its observation range, but also because it could lead to detection of proximal neoplasms.

Adult↗
PubMed1993

Increased risk of early colorectal neoplasms after hepatic transplant in patients with inflammatory bowel disease.

UNLABELLED: Inflammatory bowel disease (IBD) is associated with an increase in colon and rectal carcinoma. Immunosuppression after transplantation increases the incidence of certain types of tumors. PURPOSE: We reviewed the postoperative course of IBD patients who had undergone hepatic transplantation for primary sclerosing cholangitis to see whether there was an increase in the rate of colorectal neoplasms. METHODS: The charts of 44 patients from two institutions who had undergone a hepatic transplant for primary sclerosing cholangitis were reviewed. Of these 44 patients, 33 had IBD (32 chronic ulcerative colitis, 1 Crohn's). Of these 33 patients, 2 had previously undergone total colectomy/proctectomy and 4 died in the perioperative period. The remaining 27 patients had all undergone colonoscopic evaluation just prior to transplant. Postoperatively all patients were given prednisone, cyclosporine, and azathioprine. Minimum follow-up was 12 months; mean follow-up was 39 months. RESULTS: Three of the 27 patients (11.1 percent) developed early colorectal neoplasms (2 cancers, 1 large villous adenoma with severe dysplasia) at 9, 12, and 13 months post-transplant. All three patients were successfully treated with a total colectomy/proctectomy or resection of any remaining colon. These 3 patients had a mean 19-year history of IBD (range, 9-27 years), while the 24 patients without tumors had a mean 18-year history of IBD (range, 6-39 years). CONCLUSION: There is a subset of transplant patients with primary sclerosing cholangitis and IBD who rapidly develop colorectal neoplasms. Frequent surveillance is recommended for IBD patients in the post-transplant period.

Adult↗
PubMed2003

Colorectal neoplasms: role of intravenous contrast-enhanced CT colonography.

PURPOSE: To evaluate whether computed tomographic (CT) colonography with intravenously administered contrast material can help predict malignant differentiation of colorectal neoplasms (> or =10 mm in diameter). MATERIALS AND METHODS: Enhancement of 29 consecutive colorectal neoplasms on pre- and postcontrast CT colonographic images was retrospectively measured. The neoplasms were subsequently resected. Enhancement was calculated by subtraction of attenuation values (in Hounsfield units) obtained with precontrast and postcontrast 45-second-delay prone CT colonographic sequences. The neoplasms were graded as follows: grade 1, adenoma; grade 2, adenoma with high-grade dysplasia; grade 3, well-differentiated adenocarcinoma; grade 4, moderately differentiated adenocarcinoma; and grade 5, poorly differentiated adenocarcinoma. Correlation among size, histologic grade, and degree of enhancement was made with Pearson and Spearman coefficients. The ability of the degree of enhancement to help predict adenocarcinoma (histologic grade, > or =3) was calculated. RESULTS: Histologic-CT colonographic correlation was performed in 29 neoplasms (mean diameter, 27.9 mm; range, 10-65 mm). There was no correlation between size and degree of enhancement, size and histologic grade (R = -0.17, P =.33), or histologic grade and degree of enhancement (R = 0.23, P =.23). However, increasing enhancement was noted between grades 2 and 5. When an enhancement threshold of 40 HU was used for the diagnosis of adenocarcinoma (grades 3-5), sensitivity was 92%, specificity was 20%, positive predictive value was 50%, and negative predictive value was 75%. CONCLUSION: The degree of contrast enhancement on a 45-second-delay CT colonographic image does not correlate with size or degree of histologic differentiation, although increasing enhancement with lesser degrees of differentiation was noted.

Adenocarcinoma↗
PubMed1998

Validity of new immunological human fecal hemoglobin and albumin tests in detecting colorectal neoplasms--an endoscopy-controlled study.

BACKGROUND: Screening for occult blood by means of guaiac tests has an unsatisfactory sensitivity for the detection of colorectal neoplasms. To increase sensitivity and specificity the immunological determination of human hemoglobin and albumin in feces has been developed. The validity of analyzing only two samples from one bowel movement of either test is not known. METHODS: An immunological determination of human fecal hemoglobin and albumin using luminescence immunoassays (LIA) was performed in 739 patients with gastrointestinal complaints before scheduled colonoscopy. Each patient collected two 1 ml samples from one stool. There were no dietary restrictions. RESULTS: The sensitivity for detecting colorectal carcinomas was 95.3% (95% confidence interval 84.2-99.4%) with hemoglobin and 67.4% (95% confidence interval 51.2-80.9%) with albumin. The sensitivity for detecting large adenomatous polyps was 62.9% (95% confidence interval 50.5-74.1%) with hemoglobin and 32.9% (95% confidence interval 22.1-45.1%) with albumin. The specificity was 97% for hemoglobin, 96% for albumin and 94% for the combined test. CONCLUSIONS: The immunological determination of fecal hemoglobin is superior to albumin and has a better sensitivity for the detection of colorectal neoplasms than that reported for guaiac tests, even if two samples from one bowel movement are examined. The immunological determination of fecal hemoglobin should therefore be evaluated for use in colorectal cancer screening.

Colonoscopy↗
PubMedDate not supplied

[Role of p53 gene in colorectal neoplasms].

A prospective study on the role of the p53 gene in sporadic colorectal neoplasms is presented and the level of mutant p53 protein was measured in the tissue removed during colonoscopy from: patients previously operated for colorectal malignant neoplasms, patients with active neoplasms, first degree relatives and during regular checks. 72% of patients with an active tumour showed a positive p53 and 38% in follow-up checks. Longer follow-up periods and a major number of patients are necessary to assess the prognostic importance of the p53 protein.

Colorectal Neoplasms↗
PubMed1982

Trophic effects of gastrin on colorectal neoplasms in the rat.

This study was designed to determine the effect of gastrin on colorectal neoplasms in the rat. Multiple colon and rectal cancers were induced in each of 57 rats with methylazoxymethanol. Animals were randomly assigned to groups: (1) antral exclusion, (2) antrectomy, (3) sham, or (4) sham with subsequent pentagastrin injections. Resulting tumors were analyzed for concentration and synthesis of DNA, RNA, and protein. The number of tumors per rat and distribution of tumors within the colons did not vary among groups. Antrectomy did not alter the gastrin level, and tumors developing in these animals did not differ from those of sham controls. Antral exclusion markedly raised serum gastrin levels. Both chronic endogenous hypergastrinemia and administration of exogenous pentagastrin significantly increased tumor synthesis and concentration of DNA, RNA, and protein. We conclude that gastrin exerts a trophic effect on colorectal neoplasms in rats. This biological phenomenon suggests a tumor regulatory role for the hormone.

Animals↗
PubMed1998

Colorectal neoplasms: a retrospective study.

A total of 254 cases of colorectal neoplasms were studied. A male predominance was noted with both benign and malignant neoplasms (M:F of 4.6:1 and 1.1:1 respectively). The peak incidence was in the fifth decade. The rectum was the commonest site for both benign and malignant neoplasms (75% and 63% respectively) followed by the sigmoid colon (11% and 16% respectively). Right-sided cancers presented commonly as fungating masses (74%) while left sided cancers were predominantly of the ulcerating/infiltrating pattern (81%). The commonest benign neoplasm was tubular adenoma (39%) while the commonest malignant neoplasm was adenocarcinoma (90%) followed by squamous cell carcinoma (4%). Advanced stage on presentation was noted with these cancers, especially the mucinous adenocarcinoma variant. This may be explained by the usual late presentation of patients to orthodox doctors in our environment.

Adolescent↗
PubMed2006

Flat colorectal neoplasms and the impact of the revised Vienna Classification on their reporting: a case-control study in UK and Japanese patients.

OBJECTIVE: The prevalence and interpretation of flat colorectal neoplasms in the East or West remain highly variable. Several factors may contribute to this variability including differences in reporting techniques between Japanese and Western histopathologists when lesions are classified. The aims of this study were (i) to determine the frequency and characteristics of flat colorectal neoplasms in British and Japanese patients, (ii) to examine whether histopathological discrepancies exist between Western and Japanese-trained pathologists applying conventional classification methods and (iii) to determine the impact of the revised Vienna Classification on any differences observed. MATERIAL AND METHODS: One hundred and forty-four patients in the United Kingdom with neoplastic lesions prospectively identified by a colonoscopist, fully-trained in Japan, were age and gender-matched with 144 Japanese patients with neoplastic lesions detected by the same colonoscopist. Two British and two Japanese pathologists were independently asked to assess all neoplasms using both conventional and revised Vienna Classification methods. RESULTS: No significant difference in the frequency of flat neoplasms was found between British and Japanese patients; however, flat neoplasia from Japanese patients tended to contain more advanced pathologies. Discrepancies in histological diagnoses were observed between pathologists but which were reduced with the revised Vienna Classification. Japanese pathologists tended to diagnose higher grades of dysplasia for the same lesion compared to their British counterparts. CONCLUSIONS: The frequency of flat neoplasms in British and Japanese patients is similar. However, Japanese lesions, especially flat (IIb) and slightly depressed (IIc) neoplasms tend to be more biologically aggressive. The revised Vienna Classification achieves greater consensus.

Asian People↗
PubMed2006

Differences in characteristics of colorectal neoplasm between young and elderly Thais.

AIM: To analyze the differences of clinical characteristics of colorectal neoplasm including polyps between the elderly and young Thai patients. METHODS: Colonoscopy database from December 2000 to October 2004 was retrospectively analyzed. There were 1822 eligible patients who underwent colonoscopy (with a mean age of 56.6 years). Patients were classified into two groups: the older age group (aged > or = 60 years; n = 989) and the younger age group (aged < 60 years; n = 833). Data were recorded on age, colonoscopic indications, tumor location, colonoscopic findings and their related histological findings. RESULTS: Colorectal malignancy related lesions were more often found in the older age group (21%) than in the younger age group (12%). Left-sided lesions were detected more commonly than right-sided in both age groups in approximately two-thirds of all cases. Hematochezia showed greater association with left-sided lesions in the elderly. No relationship was found between age and neoplasm staging and severity. CONCLUSION: The chance of detecting colorectal neoplasm by colonoscopy was higher in the elderly than in the young Thais. However, both groups had the lesions predominantly located in the left side.

Adenocarcinoma↗
PubMedDate not supplied

Flat-elevated colorectal neoplasms exhibit a high malignant potential.

The potential of flat-elevated colorectal adenomas to undergo rapid malignant transformation and progression to invasive carcinoma is still under discussion. Therefore, a total of 130 colorectal neoplastic lesions > or = 1 cm in diameter were examined after endoscopic or surgical resection. Lesions were macroscopically classified into three categories: (1) flat elevation (22 lesions), superficially elevated lesion with a smooth surface; (2) granular laterally spreading tumor (GLST; 26 lesions), laterally spreading aggregates of nodules forming a lesion with granular surface, and (3) polypoid (82 lesions), pedunculated, subpedunculated and sessile polyps. The adenomatous component showed a tubulovillous architecture in 9/26 (35%) of GLST and 18/82 (22%) of polypoid lesions, however none of the flat-elevated lesions had a villous component (p <0.01; p <0.05). Carcinoma was present in 17/22 (77%) flat elevations, 37/82 (45%) polypoid lesions and 11/26 (42%) GLST (p <0.05). None of the carcinomas arising in GLST and only 1/37 (3%) of those developing in polypoid lesions were invasive carcinomas, but 4/17 (24%) carcinomas arising in flat elevations showed submucosal invasion. Moreover, while all 5 noncancerous flat elevations showed severe atypia, 17/82 (21%) polypoid lesions and 5/26 (19%) GLST showed moderate atypia. In conclusion, flat-elevated colorectal neoplasms have a high malignant potential and the role of these lesions as precursors of colorectal carcinomas deserves greater emphasis.

Adenoma↗
PubMed1990

Endoscopic Nd-YAG laser treatment of colorectal neoplasms. A four-year longitudinal study.

In order to gain a longitudinal perspective of the benefits, complications, and role of the neodymium yttrium aluminum garnet (Nd-YAG) laser in the treatment of colorectal neoplasms, we performed a review of endoscopies using the laser during a 53-month period ending in January 1989. We reviewed the records of 100 patients for details of the endoscopic procedure and demographic data. Performance status and survival were critically assessed. We performed 275 procedures on 57 men and 43 women with an average age of 76.5 years. An average of 2.75 procedures, each lasting an average of 45 minutes, were performed per patient. Half of the patients had fulgurations of rectal tumors with the common indication being bleeding. Thirteen morbid events and no deaths occurred. Ninety-six per cent of the procedures were performed with the patient under intravenous sedation. The Karnofsky performance scale applied to surviving patients revealed that 90 per cent were able to care for themselves and scored greater than 70. Average survival was 5.58 months. Our results indicate that the Nd-YAG is a safe and effective tool in the treatment of colorectal neoplasms offering palliation as well as maintenance of quality of life.

Adult↗
PubMed1994

[Blood gastrin and colorectal neoplasms].

Gastrin has a trophic effect on the mucosa of the gastrointestinal tract and seems to have the potential for promoting colonic cancerogenesis through a chronic stimulation of the epithelial proliferation. Plasma gastrin has been reported to be elevated in patients with colorectal neoplasms. The aim of the present study was to verify this observation. Presurgical serum levels of gastrin were compared between 49 patients with colorectal neoplasms and 47 controls hospitalized for other surgical lesions. Results show significantly higher gastrin levels of case group than controls: 72.72 + 85.41 vs. 46.79 + 24.09 pg/ml (p < 0.05), and provide support for the hypothesis of a gastrin-stimulated neoplastic growth enhancing at the same time the potential therapeutic role of reducing gastrin secretion.

Adenoma↗
PubMed1996

Dynamic contrast-enhanced subtraction versus T2-weighted spin-echo MR imaging in the follow-up of colorectal neoplasm: a prospective study of 41 patients.

PURPOSE: To compare dynamic contrast-enhanced subtraction (DCES) and T2-weighted spin-echo (SE) magnetic resonance (MR) imaging in the differentiation of fibrosis from recurrence during the follow-up of treated colorectal neoplasms. MATERIALS AND METHODS: Forty-one patients with 39 malignant and 16 benign lesions confirmed by means of surgery (n = 23), biopsy (n = 24), or 12-month follow-up examination (n = 8) underwent DCES MR imaging and T2-weighted SE MR imaging. Enhancement of an abnormal pelvic structure within the first 90 seconds on DCES images or high signal intensity on T2-weighted SE images was considered indicative of malignancy. RESULTS: Sensitivity, specificity, and positive and negative predictive values were, respectively, 97%, 81%, 93%, and 100% for DCES MR imaging and 77%, 56%, 81%, and 56% for T2-weighted MR imaging. The number of correctly classified lesions was significantly higher with DCES imaging compared with T2-weighted imaging (P < or = .006). CONCLUSION: DCES imaging is more accurate than T2-weighted SE imaging for differentiating fibrosis from recurrence during the follow-up of treated colorectal neoplasms.

Colon↗