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C Fenger

Publications and source records attributed to C Fenger.

At least 73 records · Page 4Linked to original sources
PubMed1993

Effect of stimulation of mucosal HCO3- secretion on acid-induced injury to porcine duodenal mucosa.

The effect of stimulation of duodenal mucosal bicarbonate secretion with vasoactive intestinal peptide (VIP) on acid-induced damage to the duodenal mucosa was studied in anaesthetized pigs in which bile and pancreatic juice were diverted from the duodenum. Mucosal damage was quantitatively assessed histologically, and mucosal blood flow was determined by means of radioactively labelled microspheres. Compared with placebo, intravenous infusion of VIP (500 pmol/kg/h) significantly stimulated duodenal mucosal bicarbonate secretion (47 +/- 13 versus 249 +/- 53 mumol/h) without concomitant changes in mucosal blood flow (51.5 +/- 7.8 versus 48.5 +/- 9.1 ml/min/100 g) or arterial bicarbonate concentration (24.2 +/- 1.1 versus 23.4 +/- 0.9 mM). The same dose of VIP increased the acid disappearance rate in the duodenum (2.2 +/- 0.14 versus 3.3 +/- 0.09 mmol/h) and reduced the extent of damage to the duodenal surface (16 +/- 2% versus 7 +/- 2%) during duodenal infusion of 0.03 M HCl but not 0.1 M HCl. We conclude that the protection offered by VIP against the small dose of acid is most likely secondary to the effect of VIP on mucosal bicarbonate secretion. Thus, this study suggests that duodenal mucosal bicarbonate secretion, independent of mucosal blood flow, is an integral factor in duodenal mucosal defence.

Analysis of Variance↗
PubMed1993

The Funen Adenoma Follow-up Study. Incidence and death from colorectal carcinoma in an adenoma surveillance program.

The results of a prospective randomized study of 1056 patients with colorectal adenomas are presented. After initial polypectomy from 1978 to 1992, patients were allocated at random to different follow-up intervals varying from 6 to 48 months, except 53 patients who were allocated to intervals of 6 months. The examinations were mainly done by colonoscopy. Ten patients developed colorectal carcinoma, a number similar to that expected (7.96), when compared with a sex- and age-matched normal Danish population. The expected number of carcinomas was also calculated from adenoma to carcinoma conversion rates estimated in other studies and compared with that observed. If all carcinomas develop in large (> or = 10 mm) adenomas or adenomas with severe dysplasia, the expected number of carcinomas would have been 62 and 110, respectively, indicating a significant reduction of carcinomas in the present study. One patient died of colorectal carcinoma, which is significantly lower than the number expected (7.58). Two patients died of complications from therapeutic and diagnostic colonoscopy--that is, 2 deaths in 3959 colonoscopies. In conclusion, the follow-up strategy has resulted in a mortality from colorectal carcinoma which is reduced when compared with the normal population, in spite of an apparently similar incidence of carcinoma. However, previous suggested adenoma-carcinoma conversion rates indicate that a major reduction of incidence actually has taken place.

Adenoma↗
PubMed1992

Can Hemoccult-II replace colonoscopy in surveillance after radical surgery for colorectal cancer and after polypectomy?

Surveillance after colorectal carcinoma and adenoma includes colonoscopy, which is a demanding procedure for the patient, doctor, and society. Therefore, it was investigated whether a simple fecal occult blood test could replace colonoscopy. Hemoccult-II (H-II) was performed before 1,244 colonoscopies in patients with previous cancer and before 328 colonoscopies in an adenoma surveillance program. The H-II test was positive in 3 of 9 patients with local recurrence, in 2 of 13 with metachronous cancer, and in 31 of 186 with adenomas. The test was positive more often in patients with large and multiple adenomas, sigmoid adenomas, and adenomas with villous elements and moderate-to-severe dysplasia, but the sensitivity did not reach more than 25 to 40 percent. It was concluded that markers more sensitive than H-II are needed to detect metachronous cancers and new adenomas. In the meantime, colonoscopy has to be used with intervals of several years, but not for detection of local recurrent cancer, which in most cases may be found by simpler means.

Chi-Square Distribution↗
PubMed1992

Echo pattern of lymph nodes in colorectal cancer: an in vitro study.

Surgical specimens from 75 patients with colorectal cancer were examined within 15 min of removal with a 7.5 MHz linear-array transducer. The echo pattern of 139 lymph nodes was analysed to evaluate previous criteria of malignancy and to establish other possible criteria, which could be tested in vivo. The pathologist examined each node without knowledge of the sonographic finding. Malignant nodes were larger than benign nodes. Of 21 nodes less than 5 mm in diameter, 20 were benign. Round nodes were malignant more often (45/78) than ovoid nodes (6/61). A homogeneous echo pattern was associated with malignancy in 39 of 82 nodes in contrast to 12 of 57 with a heterogeneous pattern. Thirty-one nodes were ovoid as well as heterogeneous and all of these were benign. A hyperechoic centre was found in 14 nodes of which two were malignant. The highest predictive value for malignancy (59%) was obtained by combining the discriminative properties of shape, homogeneity and echogenicity.

Colorectal Neoplasms↗
PubMed1992

Observer homogeneity in the histologic diagnosis of Helicobacter pylori. Latent class analysis, kappa coefficient, and repeat frequency.

Four pathologists independently examined 82 antral mucosal biopsy specimens for the presence of Helicobacter pylori and indicated whether their assessments were certain. The pathologists made a positive diagnosis in from 56% to 84% of the specimens (significant heterogeneity, p < 0.01). The frequency of uncertain diagnoses was from 4% to 20% (p < 0.01). Uncertain statements occurred more frequently among negative than among positive diagnoses. For the six pairs of observers the kappa coefficients were between 0.39 and 0.82. By a latent class analysis measures of diagnostic accuracy were calculated comparing the observers' assessments with an estimated consensus diagnosis. The predictive values of a positive diagnosis ranged from 0.70 to 1.00. By calculation of repeat frequencies--that is, the probability that an observer's statement was confirmed by another observer--it became evident that uncertain statements were less frequently (61%) confirmed than were certain ones (85%). It is concluded that observer homogeneity is only moderate with regard to the histologic diagnosis of H. pylori, which should be considered both in daily clinical routine and in scientific studies. Disagreement between observers was associated with negative diagnoses, presumably because the pathologists felt more uncertain in these cases.

Adult↗
PubMed1992

Causes of death during the first 5 years of a randomized trial of mass screening for colorectal cancer with fecal occult blood test.

The main purpose of population screening for colorectal cancer is to reduce mortality from the disease. The criteria of death from colorectal cancer are defined in the present randomized trial of 61,938 persons between 45 and 74 years old, and the need for an impartial death review committee was demonstrated. Causes of death within the first 5 years are described within subgroups of the test group and compared with those in the control group. Death rates were higher among non-responders to screening than among controls and among those in whom Hemoccult-II had been performed at least once. Persons with negative Hemoccult-II had a lower death rate than controls. The overall autopsy rate was 32%. Lethal complications from treatment of colorectal neoplasia were evaluated per se. Death from colorectal cancer occurred in 74 persons in the total screening group and in 91 among controls. Sources of bias are discussed. A method of evaluating possible benefit to those being screened is suggested. Final results cannot be expected before 1996.

Aged↗
PubMed1992

Interval cancers in screening with fecal occult blood test for colorectal cancer.

Interval cancers, which are cancers diagnosed in spite of one or more negative screening tests, were studied in a randomized population with Hemoccult-II for colorectal cancer in 61,938 persons between 45 and 74 years old. Three biannual screenings were performed from 1985 to 1991, and 52% of all the cancers detected after doing at least one Hemoccult-II test were interval cancers (81 persons). These were more advanced than cancers diagnosed after a positive Hemoccult-II test, of larger size, less frequently of Dukes stage A, more often invading neighboring organs, and less often resectable for cure. They were located in the rectum more often than cancers diagnosed by screening and cancers in controls. Otherwise, interval cancers did not differ from cancers in controls or cancers in non-responders, and all characteristics suggested that no delay in diagnosis resulted from one or more negative Hemoccult-II tests, compared with controls. However, even if screening with Hemoccult-II demonstrates a reduction in mortality from colorectal cancer, the present high number of interval cancers makes it necessary to look for other methods of screening populations for colorectal cancer.

Aged↗
PubMed1991

[Curative local excision of colorectal cancer. A prospective study].

The importance of local treatment for early colorectal cancer is apparent because of increasing endoscopical activity for diagnostic purposes and screening. Curative local treatment was attempted in 63 patients with polypoid, mobile tumours thought to be within the bowel wall and without palpable lymph nodes in the perirectal tissue. Tumours more than 3 cm in diameter were excluded, unless they were pedunculated or were believed to be adenomas with carcinoma. Removal was effected by polypectomy, piecemeal removal, peranal excision, posterior rectotomy or colotomy. Complications were few, and hospitalization was shorter than after conventional surgery, but one patient died from treatment. More extensive surgery followed in 12 patients, in whom cancer remained in the resection margin or where this could not be excluded. However, seven of the 12 patients had no residual cancer tissue. Survival without recurrence was longer in patients with tumours below 3 cm in diameter. Recurrence was seen in nine patients, but not in those with cancer limited to head and the stalk of pedunculated tumours and not with cancer limited to the luminal part of submucosa, regardless of shape of tumour. Adenoma in continuity with cancer did not influence survival significantly, but synchronous adenomas in other parts tended to increase recurrence-free survival. Local treatment is satisfactory in most patient with cancer within pedunculated polyps and in some with cancer in sessile polypopid tumours. Criteria of selection are not optimal and the use of endoluminal ultrasound examinations must be evaluated in prospective trials. At present, conventional surgery should be used when cancer in the resection margin cannot be excluded, when cancer is present in the deeper layers of muscularis propria and in patients with poorly differentiated cancers.

Adult↗
PubMed1991

[Colonoscopy after radical surgery for colorectal cancer. A 10-year prospective study of 309 patients].

Experience from ten year colonoscopic follow-up in patients after radical surgery for colorectal cancer is presented. In all, 309 patients below 76 years were included from 1978 to 1983. All had preoperative proctoscopy and barium enema. Colonoscopy was performed perioperatively, every six months the first three years, four and five years, seven to eight years and ten years after surgery. A minority had double-contrast barium enemas. Synchronous adenomas were removed during surgery and at perioperative colonoscopy and these patients had the same risk of metachronous cancer as those without synchronous adenomas. Five patients with six metachronous cancers, all had new curative surgery. Patients with synchronous adenomas had a higher risk of metachronous adenomas, but had a better prognosis than those without synchronous adenomas. Colonoscopically demonstrated intraluminal local recurrence in the colon could not be treated with new radical surgery in contrast to four out of eight intraluminal recurrences in the rectum. Most local recurrences were extraluminal and were diagnosed by other means.

Adenoma↗
PubMed1991

Melanocytes in the anal canal epithelium.

We studied the presence of melanocytes in the various epithelial zones of the anal canal, using a recently introduced melanocyte-specific antibody (HMB-45) together with antibody to S-100 protein. In normal and canals and in haemorrhoids, melanocytes, defined as intraepithelial HMB-45/S-100 positive cells, were frequently demonstrated in the anal squamous zone, only sporadically in the anal transitional zone, and not at all in the colorectal zone. In the epithelium surrounding, but clearly separated from, resected primary anal malignant melanomas, increased numbers of benign melanocytes were demonstrated in the squamous zone and transitional zone, but also in the colorectal zone. We interpret this finding as a tumour-induced proliferation of benign melanocytes normally present, but in very small numbers or in some way 'masked', in the epithelium of the upper anal canal. The demonstration of melanocytes in all three zones of the anal canal substantially supports the observation that malignant melanoma of the anal canal may originate not only below but also above the dentate line.

Anal Canal↗
PubMed1991

Anal neoplasia and its precursors: facts and controversies.

The normal anal mucosa shows a complex histology, and a large variety of tumors and lesions with more or less malignant potential may arise in this region. Several of these seem to be related to venereal diseases, homosexual behavior, and anal intercourse, and to immunosuppression. Human papilloma virus (HPV) has been identified in many cases, but the relation to the histological picture is not constant and the significance is unclear. However, these observations have helped us to identify risk groups. Histological classification is often difficult and it is likely that the reproducibility is limited. This may, in part, explain different observations with regard to frequency and biological behavior. A reliable diagnosis still largely depends on exact clinical information on location and appearance, detailed knowledge of the normal histology, and careful handling of the specimen. The revised World Health Organization (WHO) classification represents an improvement, but more variants are still identified and a classification based on conventional histology alone seems in many cases unsatisfactory. Immunohistochemistry and hybridization and other techniques hopefully will provide us with improved typing of these lesions.

Adenocarcinoma↗
PubMed1990

[Rectoscopy and Hemoccult II in irritable colon. A prospective study].

It was investigated whether Hemoccult-II test (H-II) could reduce the number of colonic examinations in patients with the irritable bowel syndrome, with normal rigid proctoscopic findings. A negative H-II was obtained in 299 patients from general practice and a positive test in nine. Colonoscopy was done in 157 and double contrast barium enema in 142 after random allocation. The nine patients with positive H-II all had colonoscopy. Among the 299 with negative H-II, colonic adenomas were detected in ten and an early cancer in an adenoma in the sigmoid colon; overlooked rectal adenomas were found in three, rectal cancer in one, rectal carcinoid in another and a coecal cancer, which could be palpated, in a third patient. Two patients with colonic cancer and one with adenoma were detected among those with positive H-II. All patients were followed by clinical examination after one year. In conclusion, colonic examination should carry a low priority in patients with symptoms of irritable bowel, negative Hemoccult-II and normal rigid proctoscopic findings performed by an experienced examiner. The investigation confirmed the recommendation of total colonoscopy in patients with a positive H-II and added support for increasing number of endoscopy services in contrast to those of diagnostic radiology, which should be reduced.

Adenoma↗
PubMed1990

Neuronal hyperplasia in the anal canal.

In a consecutive series of minor surgical specimens from the anal canal, neuronal hyperplasia was found in nine of 56 haemorrhoidectomy specimens and in four of 23 fibrous polyps. In an additional series of 14 resections of the anal canal, neuronal hyperplasia was present in six cases, of which five showed haemorrhoids. In all cases, neuronal hyperplasia was located in the submucosa beneath squamous epithelium and extended over an area from 5 to 12 mm. Immunohistochemically, the foci of hyperplasia were found to consist of both neuronal and Schwann cell components. Staining for vasoactive intestinal peptide, neuropeptide Y and calcitonin gene related peptide, did not demonstrate any increased terminal density. It is suggested that anal neuronal hyperplasia in these cases represents an acquired lesion due to local mechanical influence.

Anal Canal↗
PubMed1990

Observer reproducibility in grading dysplasia in colorectal adenomas: comparison between two different grading systems.

The two most well known and well defined grading systems for dysplasia in colorectal adenomas were compared with regard to reproducibility. The Konishi-Morson system (KMS) operates with several histological and cytological variables and grades of mild, moderate, and severe dysplasia. The Kozuka system is based on the extent of nuclear pseudostratification and also has three grades of dysplasia (III-V). As the group of severe dysplasia is very large in this system, it was extended with two higher grades, similarly based on individual histological criteria, known hereafter as the extended Kozuka system (EKS). Fifty six adenomas were graded by two observers, each observer grading twice according to the KMS criteria and twice according to EKS criteria. Intraobserver reproducibility was excellent for the KMS and moderate for the EKS, but this was not significant. The overall interobserver reproducibility was similar (moderate) for the KMS and for the EKS. Kappa values for interobserver reproducibility on individual categories were excellent for severe dysplasia according to the KMS, but low for all other categories in both systems. By simplifying both systems into two groups a high reproducibility can be obtained, but this implies that all the original grades (III-V) for the EKS must be grouped together. It is therefore recommended that a simplified KMS is used for further studies on the biological importance of dysplasia and for comparison between histological changes and other markers for colorectal neoplasia.

Adenoma↗
PubMed1989

[Prognosis in synchronous liver metastasis from colorectal cancer. A multicenter study of patients with cancer of the rectum and cancer of the rectosigmoid colon].

A prospective investigation of 188 patients with cancer of the rectum and rectosigmoid colon with synchronous liver metastases is described. The mean survival time for 183 patients who did not receive any treatment for the liver metastases was six months and only one survived for longer than 37 months. After extirpation of the primary tumour, the most significant prognostic factors were etrahepatic metastases, enlarged liver on account of metastases and more than three liver metastases. Serum basic phosphatases had the greatest significance among a series of laboratory tests. In the sub-groups with the best possible prognoses, the mean survival time was 12 months. 25% five-year survival has been described in the literature following resection of the liver in patients with a maximum of three metastases, no other metastases and age under 70 years. Provided this holds true, liver surgery will be a therapeutic possibility in at least 100 patients per annum in Denmark with synchronous liver metastases and 25 of these will be cured. This figure requires an improved programme for the diagnosis of synchronous liver metastases than at present and the same high frequency of extirpation of the primary colorectal cancer on a national basis which was achieved in the present material.

Aged↗
PubMed1989

Repeated screening for colorectal cancer with fecal occult blood test. A prospective randomized study at Funen, Denmark.

Two screenings with Hemoccult-II were performed in a randomized study, allocating 30,970 persons to screening and 30,968 as controls in a population of 140,000 between 45 and 74 years old on the island of Funen, Denmark. The test was completed in 20,672 initially and in 18,779 of these during rescreening 2 years later. Positive H-II tests were found in 215 and 159 persons during the two screenings, respectively. A total colonoscopy was performed in 187 and 144, and cancer was detected in 37 and 13 and adenomata in 86 and 76, respectively. Interval cancers had developed in 40 persons at the end of the second screening, and 39 non-responders had developed cancer. Cancer was diagnosed in 115 controls and an adenoma in 100 during the same period. Interval cancers presented as rectal cancers more frequently than those detected by screening. Early cancers were more frequent in the screening group, and, accordingly, more patients had curative and also less extensive surgery, with a low postoperative mortality. The total number of deaths from colorectal cancer was 37 in the screening group, including interval cancers and cancers in non-responders and persons who developed cancer before they could be invited, which suggests a reduction in mortality of 27% (51 deaths among controls, compared with 37). The reduction is as yet not statistically significant, and final evaluation must await at least one more screening, ending in 1990, and a follow-up of some years. Removal of more large adenomas during screening makes it possible that the incidence of cancer will decrease.

Adenoma↗