[Spincter preservation after selective chemoradiotherapy of rectal cancer. Interim results of the OCUM study]. / Spinktererhalt nach selektiver Radiochemotherapie des Rektumkarzinoms. Zwischenergebnisse der OCUM-Studie.

BACKGROUND: In a prospective multicenter observational study (OCUM) neoadjuvant chemoradiotherapy (nRCT) was selectively administered depending on the risk of local recurrence and based on the distance between tumor and mesorectal fascia in pretherapeutic high-resolution magnetic resonance imaging (MRI). OBJECTIVE: Frequency and quality of abdominoperineal excision (APE) and sphincter preserving operations. PATIENTS AND METHODS: Of 642 patients treated in 13 hospitals 389 received surgery alone and 253 nRCT followed by surgery. By univariate and multivariate analysis risk factors for APE were determined. Quality parameters were the quality grade of mesorectal excision, the pathohistological involvement of the circumferential resection margin and intraoperative local dissemination of tumor cells. RESULTS AND DISCUSSION: In 12.8 % of the patients APE was performed. Independent risk factors for APE were tumor location in the lower third of the rectum and the individual hospitals, where APE varied between 0 and 32 %. This variation was chiefly caused by the different case mix. Hospitals with a high APE rate (> 30 %) treated significantly more patients with very low lying carcinomas (< 3 cm above the anal verge) and more advanced tumors. The median height of the tumor in cases of APE was nearly equal in all participating hospitals. Independent on the number of cases the quality of rectal surgery was high. Within the patient groups of primary surgery and nRCT the oncological quality parameter did not significantly differ between sphincter preservation and APE. As far as sphincter preservation is concerned the results justify a selective application of nRCT in patients with rectal carcinoma. The long-term results still have to be awaited.

Activation of extracellular regulated kinases (ERK1/2) but not AKT predicts poor prognosis in colorectal carcinoma and is associated with k-ras mutations.

Signal transduction and modulation represent central mechanisms in cellular processes such as cell-cycle regulation, oncogenesis, and apoptosis. The aim of this study was to determine the prognostic relevance of two kinases important in the regulation of cell proliferation and apoptosis in 135 colorectal cancer cases: AKT and extracellular regulated kinases (ERK1/2). We investigated the relationship of phospho-ERK1/2 (pERK1/2) and phospho-AKT (pAKT) with associated parameters (EGFR, COX-2, cyclin-D1), proliferative activity (Ki-67), and apoptosis (TUNEL) using immunohistochemistry. Additionally, the k-ras gene was screened for mutations to determine its putative association with ERK1/2 activation. Activation of ERK1/2 but not AKT correlated statistically with the presence of k-ras mutations (P = 0.015). Survival analysis of phospho-ERK1/2 immunoexpression showed a significant correlation with decreased overall survival (OS). The multivariate Cox regression analysis identified pERK1/2 as an independent prognostic parameter (P = 0.005). Activation of ERK1/2 in colorectal cancer may indicate aggressive tumor behavior and may constitute an independent prognostic factor. Furthermore, our data suggest that mutations of the k-ras oncogene may induce activation of ERK1/2. We propose immunohistochemical determination of pERK1/2 status as a promising candidate for the identification of high-risk patients who would benefit from new anticancer drugs targeting the ERK pathway.

Cytology and image cytometry after colonic lavage: a complementary diagnostic tool in patients with ulcerative colitis.

BACKGROUND: Patients with extensive, long-standing ulcerative colitis have increased risk of colorectal cancer. AIMS: To improve the detection of high-risk patients, using a combination of colonic cytology, histology, and DNA image cytometry after segmental colonic lavage. PATIENTS: A series of 16 patients (8 high-risk patients) with ulcerative colitis were investigated. METHODS: After segmental lavage step, biopsies were obtained. Gradient centrifugation of the colonic fluid was performed for isolation and purification of epithelial cells. The smears and biopsy specimens obtained were stained for routine interpretation and for DNA image cytometry. RESULTS: Segmental lavage could be performed in all patients. Specimens from two high-risk patients showed low grade dysplasia and atypia by means of histology and cytology, respectively. In one patient, without increased colorectal cancer risk, atypia was detected. Three patients in the high-risk group, two of those diagnosed as positive for dysplasia and atypia, showed aneuploidy histologically and cytologically. DNA aneuploidy, in cytological material, was found exclusively in three low-risk patients, one of those had atypia cytologically. CONCLUSIONS: Isolation and purification of epithelial cells after segmental colonic lavage using density gradient centrifugation can be performed as part of routine endoscopy. It provides information about atypical cells and DNA aneuploidy as additional markers of malignant transformation. The combination of cytologic examination and DNA image cytometry might improve the detection of high-risk ulcerative colitis patients.

Fluorescence endoscopy using a fluorescein-labeled monoclonal antibody against carcinoembryonic antigen in patients with colorectal carcinoma and adenoma.

BACKGROUND AND STUDY AIMS: Various methods of fluorescence excitation and detection have been developed in gastrointestinal endoscopy. This study reports an endoscopic technique using locally applied fluorescein-labeled antibodies for in-vivo detection of colorectal dysplasia and carcinoma. PATIENTS AND METHODS: Fluorescence endoscopy with a fluorescein-labeled monoclonal antibody against carcinoembryonic antigen (CEA) was carried out in 27 patients with colonic polypoid lesions. During conventional colonoscopy, the monoclonal antibody was applied directly onto the mucosal surface. After an incubation time of 10 min, specific fluorescence was visualized with a conventional endoscope whose optical range was increased via two narrow-band filters. RESULTS: Fluorescence in vivo was present in 19 out of 25 carcinomas and in three of eight adenomas. The technique failed in the presence of mucosal ulceration or bleeding. One fluorescence-positive villous adenoma showed high-grade dysplasia, and another fluorescence-positive polypoid lesion was diagnosed as carcinoma in adenoma. Normal-appearing mucosa was fluorescence-negative in all cases. Endoscopic fluorescence significantly correlated with the CEA expression of luminal epithelial cells as determined immunohistochemically (Wilcoxon-Mann-Whitney U-test, P < 0.01). In all cases without ulceration or bleeding, the specificity of fluorescence endoscopy was 100%, the sensitivity was 78.6%, and the accuracy was 89.3%. CONCLUSIONS: Fluorescence endoscopy using fluorescein-labeled monoclonal antibody against CEA was shown to be positive in most cancers and some adenomas. Further and larger studies will be needed to demonstrate the value of this technique for differential diagnosis.

Signet-ring cell carcinoma of unknown primary location. Metastatic to lower back musculature - remission following FU/FA chemotherapy.

The detection of gastrointestinal signet-ring cell carcinoma by endoscopy can be a diagnostic challenge. The main clinical features include atypical metastasis and a poor prognosis. We present a case of a metastasizing signet-ring cell carcinoma with unknown primary location arising in 71-year-old female. Following 6 cycles of a routine intravenous FU/FA chemotherapy, an almost complete remission could be observed. After 2 years of follow up, metastatic recurrence was detected to the lower back musculature. This case report emphasizes the difficulties in diagnosing signet-ring cell carcinoma by endoscopy and demonstrates an unusual clinical course.

Clinical differences between benign and malignant pheochromocytomas.

Most pheochromocytomas can be cured by resection. In view of the unfavourable prognosis for surgical therapy in cases of late tumour detection and malignant tumours, the aim of the present study is to differentiate between typical signs and symptoms of malignant versus benign pheochromocytomas. We investigated the records of 133 patients retrospectively (1967-1998). In cases of benign tumours (104 of 133, mean age 42+/-15.8 years) tumour size was 5.9+/-3.4 cm, and history was 47.4+/-75.4 months. 7.7% of the tumours were extraadrenal, and 77% had paroxysmal manifestations. The other 29 patients (mean age: 39.2+/-21.9 years) had malignant lesions (tumour size: 9.4+/-5.9 cm (p=0.0022); history: 7.4+/-5.6 months (p=0.0137); extraadrenal: 24.1% (p=0.0219); paroxysmal: 37.9% (p=0.0012)). Symptoms of patients with benign tumours were hypertension (80%), headaches (42.3%), sweating (30.8%), tachycardia (26%) and pallor (24%) (Malignant: Hypertension 46%, p=0.0873; headaches 11%, p=0.0008; sweating 11%, p=0.0196; tachycardia 14%, p=0.1961 and pallor 0%, p=0.0010). Abdominal pain and dorsalgia occurred more frequently in malignant pheochromocytomas (26% versus 7%, p=0.0014). Unusually short histories and extraadrenal localization appear to be suspicious for malignancy. The "typical" clinical signs and symptoms occur more frequently in patients with benign tumours and can therefore be regarded as typical signs of benign pheochromocytomas.

A possible explanation for the frequent concomitance of arterial hypertension and multiple renal arteries.

In more than 20% of subjects, at least one kidney is found to be supplied by more than one artery arising from the aorta. This aberrant renovascular anatomy has been reported in the literature to occur in up to 80% of patients who suffer from essential hypertension. Predominant numbers of the so-called 'accessory' vessels are longer and narrower than the segmental arteries arising in the main renal artery. As a result (in accordance with Poiseuille's law of fluid flow), the renal segments supplied by these 'accessory' vessels may have lower levels of blood pressure than the remainder of the parenchyma, thereby increasing the renin secretion. This hypothesis could be significant in terms of finding a causal treatment for a disorder induced by such a mechanism. We first review the literature in which the frequency of these vascular anomalies in normotensive and hypertensive patients is described, and then advance a hypothesis explaining the frequent incidence of essential hypertension in these subjects, as well as the ramifications of this phenomenon.

Conn's syndrome and bilateral renal artery stenosis in the presence of multiple renal arteries.

We report the case of a 42-year-old male who was admitted to our hospital after an acute hypertensive crisis despite four-way anti-hypertensive therapy. The renal scintigraphy, the excretory urogram and the biochemical profile performed two years before were unremarkable, except for slightly elevated serum creatinine and plasma aldosterone, in presence of normal aldosterone/renin ratio. The renal arterial angiography that was performed despite a second unremarkable scintigraphy revealed high-grade bilateral arterial stenosis in the presence of multiple renal arteries. Following dilatation of the left stenosis, the aldosterone/renin ratio was pathologic. Recumbent and orthostatic aldosterone values were 830 pg/ml and 1824 pg/ml, respectively, and recumbent and orthostatic renin values were 0.82 and 1.21 ng angiotensin I/ml/h, respectively. The abdominal computed tomography performed to investigate a possible concomitant Conn's syndrome resulted in the detection of a left adrenal tumor. After resection of the lesion, plasma-aldosterone levels normalized and a pronounced rise in serum potassium levels was observed. Following angioplasty of the right renal artery stenosis, blood pressure could easily be managed with combined beta and calcium channel blocker therapy. Particularly in cases of bilateral (but also in the presence of unilateral) renal artery stenosis in association with Conn's syndrome, all the available screening methods for these disorders can fail. In cases of poor response to combination hypertensive therapies, renal arteriography and a fludrocortisone-suppression test should be performed in order to rule out both renal arterial stenosis and Conn's syndrome, even in the absence of clinical and biochemical findings suspicious for either disorder.

Outcome of surgical intervention for rectoneovaginal fistulas in Mayer-Rokitansky-Kuester-Hauser syndrome.

Creation of a neovagina to treat vaginal atresia or aplasia in Mayer-Rokitansky-Kuester-Hauser syndrome must always be followed by long-term application of dilators to avoid shrinkage. However, rectoneovaginal fistulas are caused by chronic alteration and consecutive necrosis of the posterior neovaginal wall. We evaluated retrospectively the postoperative outcome of rectal wall and neovaginal reconstruction using a standardized surgical technique in an exclusive collection of women. Eight women with a mean age of 28 years (range 22-31 years) were treated for rectoneovaginal fistulas in our clinic. Preoperatively, proctoscopy, sphincter manometry, endoluminal rectal ultrasonography, and colonoscopy were performed; and regular postoperative follow-up by digital examination and rectoscopy were obligate. The standard surgical procedure via a perineal approach included fistulectomy and closure of the mucosa and rectal wall followed by a levatorplasty. All but one woman had a temporary colostomy. After 2 weeks the patients were allowed to wear vaginal dilators of a smaller size. Within the mean follow-up period of 20 months, reintervention was necessary twice because of late fistula relapse detected by proctoscopy, barium enema, and subjective symptoms. Morbidity was 25% (n = 2) due to secondary superficial wound healing or urinary tract infection. The average time of the hospital stay was 13 days (10-14 days). One patient complained of vaginal shrinkage and underwent local estrogen therapy with a good functional result 3 months later. Proper fistulectomy and surgical reconstruction with interpositioning of well perfused muscle layers achieved good functional outcome with an acceptable number of minor morbidities. Local estrogen treatment is helpful for avoiding scarification and decreasing the neovaginal size.

Diagnostic value of DNA image cytometry in ulcerative colitis.

The increased risk of colorectal cancer in patients with extensive, long-standing ulcerative colitis is well established. The interpretation of dysplasia as the common precursor lesion of colorectal cancer in ulcerative colitis is, however, subject to inter- and intraobserver variation. The histologic diagnosis is particularly difficult in the presence of acute inflammation. Therefore, the analysis of ploidy patterns might be a more objective diagnostic tool. In the present study, the correlation of ploidy and dysplasia of the colonic mucosa was evaluated in the absence and presence of inflammation. Image cytometry was performed on 561 fixed, paraffin-embedded tissue specimens from 67 patients with ulcerative colitis. Twenty patients had long-standing and extensive disease, including eight patients in whom the colitis was associated with colorectal cancer. Dysplasia was only found in patients with long-standing colitis or with colorectal cancer and was significantly more often diagnosed in the case of concomitant inflammation. On the other hand, aneuploid patterns were shown to occur independent of inflammatory activity. Aneuploidy was present in all colorectal carcinomas associated with ulcerative colitis and in 46.2% of specimens with dysplasia. Moreover, aneuploidy was detectable in four of 12 samples with low-grade dysplasia as well as in one case devoid of any dysplastic alteration. Ulcerative colitis patients with low-grade dysplasia plus aneuploidy probably represent a subgroup that might be at higher risk of developing colorectal cancer than patients with low-grade dysplasia alone. All in all, image cytometry analysis might be instrumental in identifying neoplastic lesions even in cases of increased inflammatory activity or regenerative change.

Hypertension associated with multiple renal arteries may be renin-dependent.

OBJECTIVE: Subjects with multiple renal arteries have been shown to suffer more frequently from hypertension and to have higher blood pressures than subjects whose kidneys are supplied by single renal arteries. This study was carried out to determine whether subjects with multiple renal arteries also have higher renin activity. METHODS: We studied 62 consecutive patients who had undergone angiography for various reasons. They were divided into two groups. Group A comprised 29 patients whose kidneys were supplied by single arteries (male :female ratio 1.63, mean age 51.8 +/- 1.9 years) while Group B comprised 33 patients with multiple renal arteries (male:female ratio 2, mean age 47.3 +/- 2.3 years). RESULTS: Before stimulation with frusemide, the plasma renin in Group A was 0.79 +/- 0.13 ng angiotensin l/ml per h, while in Group B the corresponding figure was 1.73 +/- 0.38 ng angiotensin l/ml per h. This difference was statistically significant (P= 0.0127). Thirty minutes later the plasma renin level in Group A was 2.43 +/- 0.37 ng angiotensin l/ml per h versus a level of 3.86 +/- 0.53 ng angiotensin l/ml per h in Group B (P= 0.0169). Again, 30 minutes later the level was 2.59 +/- 0.4 ng angiotensin l/ ml per h in Group A, versus 3.79 +/- 0.59 ng angiotensin l/ ml per h in Group B (P= 0.0495). CONCLUSIONS: We conclude that patients with multiple renal arteries constitute a group who have high plasma renin activity and may therefore be prone to develop arterial hypertension.

[Fulminant necrotizing fasciitis secondary to Crohn's disease]. / Fulminante Fasciitis necroticans bei Morbus Crohn-assoziiertem Verlauf.

Necrotizing fasciitis is a life-threatening infection, commonly caused by group A streptococci, which has to be treated by surgical exploration and debridement during the first 24 h. Clinical clues are severe pain, in some cases followed by the appearance of bullous formations, and the detection of gas in the soft tissues by computed tomography or MRI. In addition to that, the infection is characterized by rapid inflammatory progression, producing a highly life-threatening situation. Diagnosis is finally based on surgical exploration obtaining specimens for culture and histopathologic examination. Debridement and exploration, in some cases amputation of the extremity, are indicated as soon as possible. Antibiotic therapy increases efficacy too, but there is no substitute for surgical treatment. Inflammatory bowel disease (Crohn's disease in this case) followed by necrotizing fasciitis is rarely mentioned in the literature. Therapeutic management in a situation of immunosuppression is discussed by illustration of an actual case.

Increased levels of promutagenic etheno-DNA adducts in colonic polyps of FAP patients.

Nonsteroidal anti-inflammatory drugs (NSAIDs) can regress adenomas in patients with familial adenomatous polyposis (FAP), and the mechanism involves inhibition of cyclooxygenases (COX). Reactive intermediates formed during the arachidonic acid cascade, notably by COX-2, which is upregulated in polyps of FAP patients, may promote various stages of the polyp --> adenoma --> carcinoma sequence. Etheno-DNA adducts can be derived from reactive intermediates generated during arachidonic acid metabolism and lipid peroxidation. We tested this hypothesis in colonic polyps from FAP patients and colorectal tissue from cancer patients to see whether increased formation of etheno-DNA adducts occurs. Using an ultra-sensitive and specific immunoaffinity/(32)P-postlabelling method, 1, N(6)-ethenodeoxyadenosine (straightepsilondA) and 3, N(4)-ethenodeoxycytidine (straightepsilondC) were quantitated in epithelial cell DNA from asymptomatic colon, FAP polyps and colon tumor tissues. Mean adduct levels in FAP polyps were 65 straightepsilondA/10(9) and 59 straightepsilondC/10(9) parent nucleotides, being 2 to 3 times higher than in unaffected colon tissue (p < 0.02 for straightepsilondA; p < 0.05 for straightepsilondC). Adduct levels in colonic epithelia decreased in the order: FAP polyps > tumor-adjacent tissue > tumor, normal and tumor-distal tissue. Based on this study, requiring confirmation in a larger number of patients and in experimental models, we have demonstrated the formation of promutagenic etheno-DNA adducts in adenomatous polyps of FAP patients that may contribute to genetic instability and cancer progression.

Recurrent rectoneovaginal fistula caused by an incidental squamous cell carcinoma of the neovagina in Mayer-Rokitansky-Küster-Hauser syndrome.

OBJECTIVE: Mayer-Rokitansky-Küster-Hauser syndrome is a congenital malformation characterized by an absence of the vagina associated with a variable abnormality of the uterus and the urinary tract but functional ovaries. Surgical correction requires the creation of a neovaginal canal by the performance of a neovaginoplasty and an accurate long-term application of an artificial phallus phantom to avoid secondary shrinkage of the canal. Due to the chronic alteration of the posterior neovaginal wall, ulcers and consecutive fistulae may occur. We report the clinical course of a female who required surgical intervention for a rectoneovaginal fistula and developed a recurrence of the fistula due to one of the extremely rare squamous cell carcinomas of the neovaginal epithelium in order to show potential diagnostic and therapeutic features. METHOD: The systematic report of a case is presented. RESULT: Almost 13 years following the initial construction of a neovagina the patient developed a single-tract rectoneovaginal fistula. After surgical repair she represented with a recurrence due to a vast squamous cell carcinoma of the former operation site. Tumor en bloc resection was performed and currently (follow-up: 4 months) she has no signs of new tumor progression. CONCLUSION: Creation of a neovagina is the standard procedure for treating vaginal atresia or aplasia. Because of the long clinical course postoperatively, complications may occur. This report of a case of a malignant transformation in neovaginal epithelium shows the potential risk of malignancy and underlines the necessity of a close follow-up.

Cost containment through L-alanyl-L-glutamine supplemented total parenteral nutrition after major abdominal surgery: a prospective randomized double-blind controlled study.

BACKGROUND & AIMS: Glutamine is recognized as a conditionally essential amino acid. Recent studies indicate that glutamine-containing total parenteral nutrition improves nitrogen economy, enhances gastrointestinal and immune functions and shortens hospital stay. METHODS: Thirty-seven patients (19 w and 18 m; age 61. 4+/-10.4 years; BMI 23.7+/-2.8 kg/m(2)) following major abdominal surgery receiving an isonitrogenous isoenergetic TPN with or without alanyl-glutamine supplementation (0.5 g/kg BW/day), were evaluated in a double-blind, randomized, controlled trial over a five-day period by measuring nitrogen balance, selected biochemical parameters and length of hospital stay. RESULTS: Supplemental alanyl-glutamine improved the overall mean (-3.5+/-1.6 vs. -5.5+/-1. 4 g N;P<0.05) and cumulative nitrogen balance (-14.1+/-9.1 vs. -21.7+/-11.4 g N;P<0.05) compared with the isonitrogenous, isoenergetic standard regimen. Alanyl-glutamine normalized plasma glutamine concentration and reduced the length of hospital stay (12.8+/-2.6 vs. 17.5+/-6.4 days;P<0.05). CONCLUSIONS: The results of the study confirm that supplementation with synthetic alanyl-glutamine dipeptide is associated with cost containment due to shortened hospitalization and improved nitrogen economy.

An assessment of diagnostic procedures preparatory to retroperitoneoscopic removal of adenoma in cases of primary hyperaldosteronism.

The goal of this study was to improve assessment of diagnostic measures for lateral localization of aldosterone-producing adrenal adenomas preparatory to retroperitoneoscopic removal, in view of the fact that this technique allows for only unilateral access. A retrospective study was carried out of the medical records of 64 patients (38 women, 26 men, average age 46.8+/-11.2) who underwent surgery at University Hospital, Münster, between 1969 and 1998. Seventeen of the 64 patients presented with hyperplasia and 47 had adrenal adenoma. In cases of hyperplasia, computerized tomography imaged a false-positive unilateral tumor 10 times, a false-negative 3 times, and a unilateral hyperplasia 1 time (ultrasonography: tumor 2 times, false-negative 3 times; 131I-Iodomethylnorcholesterol scintigraphy: tumor 5 times, false-negative 1 time, correct 1 time). In cases of adenoma, computerized tomography yielded accurate results 40 times, imaged a false-negative 2 times, and indicated the incorrect side 1 time (Ultrasonography: false-negative 12 times, correct side 9 times, incorrect side 1 time; 131I-Iodomethylnorcholesterol scintigraphy: correct side 19 times, false-positive (both sides) 5 times, negative 3 times, incorrect side 2 times). Venous sampling, which was carried out seven times, yielded accurate results six times, and failed technically one time. Venous sampling appears to be the method of choice for preoperative lateral localization. Thus, retroperitoneoscopic treatment of Conn's syndrome should not be carried out unless venous sampling is carried out first.

Interleukin (IL)-13 and IL-4 are potent inhibitors of IL-8 secretion by human intestinal epithelial cells.

Intestinal epithelial cells are able to produce soluble mediators that initiate or amplify inflammatory events in the intestinal mucosa. Interleukin (IL) -8 is suggested to be a cytokine playing a major role during the acute and chronic processes in inflammatory bowel disease (IBD). TH-2 cytokines have been described as down-regulating the inflammatory response. We analyzed the effects of IL-10, IL-13, and IL-4 on IL-8 secretion in intestinal epithelial cells. The human colonic epithelial cell line Caco-2 and freshly isolated intestinal epithelial cells were used. Cells were stimulated with IL-1beta after treatment with TH-2 cytokines. Levels of IL-8 were determined by employing enzyme-linked immunosorbent assay (ELISA). Stimulation with IL-1beta results in a time-dependent IL-8 secretion. The addition of IL-4 and IL-13, but not IL-10, to activated epithelial cells resulted in a strong decrease in IL-8 secretion. Maximal inhibition required that TH-2 cytokines be added up to 60 min before or simultaneous with stimulatory agents. We present novel findings that IL-4 and IL-13 strongly down-regulate IL-8 secretion from intestinal epithelial cells. A microenvironment containing high concentrations of IL-4 and IL-13 may alter the recruitment of immune cells to enterocytes at least partly by inhibiting IL-8 production. This inhibition might diminish the severity of the intestinal inflammatory response and, thus reduce clinical disease activity.

Density gradient centrifugation of colonic fluid after segmental lavage: a method of purification of exfoliative epithelial colonic cells for cytological interpretation and image cytometry in patients with long-standing ulcerative colitis.

OBJECTIVES: Patients with extensive, long-standing ulcerative colitis (UC) have an increased risk for developing colorectal cancer. In this study, we wanted to establish a method for retrieving cytological material after segmental colonic lavage for further cytopathological investigations and for performing DNA image cytometry. METHODS: Ten patients with long-standing and extensive ulcerative colitis and 10 patients without macroscopic abnormalities were investigated. After segmental colonic lavage during routine colonoscopy a three-layer (1.146, 1.075, and 1.046 g/ml, respectively) density gradient centrifugation of the retrieved colonic fluid was performed for isolation and purification of the epithelial cells. For identification of the epithelial cells flow cytometry with monoclonal antibody against cytokeratin and counterstaining with propidium iodine was performed. The smears obtained were stained for routine cytopathological interpretation and for DNA image cytometry. RESULTS: In eight of 10 UC patients and in nine of 10 control group patients adequate cytological material could be obtained. The band on top of the density gradient at 1.046 g/ml could be identified as the epithelial cells. Atypical cells were found in smears of three UC patients. In these patients and in one additional patient aneuploid stemlines could be detected. In smears of control group patients neither atypical cells nor aneuploidy were present. CONCLUSIONS: Isolation and purification of epithelial cells after segmental colonic lavage by using density gradient centrifugation was performed. This cytological material is adequate for cytopathological interpretation and for DNA image cytometry. Information about atypical cells and DNA aneuploidy as an additional marker of malignant transformation in UC patients was obtained. The combination of cytological examination and DNA image cytometry might improve the detection of UC patients with high risk for colorectal cancer.

Cellular localization of cyclo-oxygenase isozymes in Crohn's disease and colorectal cancer.

Deregulation of cyclo-oxygenase isozyme expression has been shown to be a consistent feature of inflammatory bowel diseases and colorectal cancer in humans. This study investigated the cellular localization of aberrant cyclo-oxygenase expression in normal and diseased colon. Biopsies of seven normal colonic tissues, eight tissue samples from patients suffering from Crohn's disease, five polyps from patients with familiar adenomatous polyposis coli, and ten sporadic adenocarcinomas were analyzed using isozyme-selective immunoprecipitation, western blotting, and immunohistochemistry. Cyclo-oxygenase-1 expression was demonstrated in normal human colon, Crohn's disease, and colorectal tumors. In normal colon and also in adenomatous polyps, cyclo-oxygenase-1 specific immunosignals were localized to epithelial cells of the upper part of the crypts and endocrine cells of the lower part. In Crohn's disease cyclo-oxygenase-1 expression was restricted to cells of the inflammatory infiltrate. While barely detectable in normal colon, cyclo-oxygenase-2 protein was strongly increased in epithelial cells located in the uppermost part of the crypts, in surface epithelial cells, and in mononuclear cells of the lamina propria of Crohn's disease. The constitutive overexpression of cyclo-oxygenase-2 protein observed in the majority of the adenomatous polyps and all adenocarcinomas was attributed to both epithelial and interstitial cells in that the latter predominated in adenomas, and epithelial cells were the prevailing cyclo-oxygenase-2 expressing cell type in adenocarcinomas. In conclusion, both autocrine and paracrine effects of aberrant cyclooxygenase-2 expression may contribute to the development of Crohn's disease and colonic tumor development.