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M Stolte

Publications and source records attributed to M Stolte.

At least 55 records · Page 3Linked to original sources
PubMed2004

Esophagitis in an adolescent patient with Crohn's disease after changing treatment from prednisolone to budesonide.

Studies have demonstrated that budesonide is effective in the treatment of active Crohn's disease. Due to its extensive hepatic metabolism, budesonide has much lower adverse events compared to prednisolone. Consequently, the low systemic availability restricts its application to Crohn's disease of the terminal ileum and the colon. Esophageal ulceration is a rare complication of Crohn's disease. This article describes the case of a young lady who presented at the age of 16 with active Crohn's disease of the terminal ileum and the colon without dysphagia or pain in the chest. Her disease was successfully treated with prednisolone for almost two years. Because of weight gain, acne, and moon face she was switched to budesonide. A few days later she presented with intractable pain of the esophagus, dysphagia, and inability to eat. Endoscopy demonstrated aphthous ulcerations of the esophagus and the histology was compatible with Crohn's disease. After two weeks of treatment with prednisolone all symptoms resolved and at follow-up gastroscopy ulcers had disappeared.

Adolescent↗
PubMed2004

[Gastrointestinal stromal tumours (GIST) of the jejunum in a patient with neurofibromatosis type 1 (von Recklingshausen's disease)].

CASE REPORT: A 72-year-old female patient with known neurofibromatosis type 1 was admitted to the hospital with symptomatic anaemia and a history of melaena. Upper and lower endoscopy did not show any signs of bleeding. Ultrasound and computed tomography revealed an abdominal mass. The histological analysis of a US-guided puncture showed a mesenchymal tumour with spindle-shaped appearance. Laparotomy revealed two jejunal tumours which could be classified as gastrointestinal stromal tumours (GIST) by immunohistochemistry. CONCLUSION: Patients with neurofibromatosis type 1 have an increased risk of developing gastrointestinal tumours including rare types such as GIST. Because the localisation in the small intestine by conventional endoscopy can be difficult, further diagnostic means such as ultrasound, computed tomography or possibly capsule endoscopy should be considered.

Aged↗
PubMed2004

Histological analysis of endoscopic resection specimens from 326 patients with Barrett's esophagus and early neoplasia.

BACKGROUND AND STUDY AIMS: Endoscopic resection has been recommended as a local curative approach for Barrett's neoplasia, but large series are still rare. In the present study we analyzed the histological characteristics of endoscopic resection specimens of Barrett's neoplasia. PATIENTS AND METHODS: 742 endoscopic resection specimens obtained from 326 patients were assessed. The following histological characteristics were evaluated: type of neoplasia, grade of differentiation, depth of infiltration, invasion into lymphatic and blood vessels, and resection status (tumor-free margins were regarded as indicating R0 status). RESULTS: 31 patients had no neoplasia and were excluded from the analysis. Among the remaining 295 patients (711 resection specimens), histological findings were: low-grade intraepithelial neoplasia, 1.0 %; high-grade intraepithelial neoplasia, 2.7 %; and mucosal carcinoma 80.3 %. Carcinomas infiltrating the submucosal layer were rare (sm1 7.5 %; sm2 3.7 %; sm3 4.8 %), as were those invading lymph vessels (3.5 %), and there were none with venous invasion. Most of the carcinomas were well-differentiated (72.2 %), and many of these (92.7 %) were limited to the mucosa, in contrast to moderately and poorly differentiated carcinomas (73.7 % and 22.7 %, respectively). R0 status was achieved in 74.5 % of patients; in 47.8 % this was after repeated endoscopic resection. In 26.8 % of patients, R0 resection was achieved at the first attempt. CONCLUSIONS: Our study demonstrates that early Barrett's neoplasms removed by endoscopic resection are mostly limited to the mucosa, are well to moderately differentiated, and very rarely show invasion of the lymph or blood vessels. Although these lesions seem to be low risk with regard to metastatic spread and therefore treatable endoscopically, improved endoscopic resection methods for achieving one-piece (en bloc) R0 resection should be developed.

Adenocarcinoma↗
PubMed2004

Attempted endoscopic en bloc resection of mucosal and submucosal tumors using insulated-tip knives: a pilot series.

BACKGROUND AND STUDY AIMS: Endoscopic mucosal resection (EMR) of early gastrointestinal cancers has been shown to be effective in treating mucosal malignancies, but en bloc resection (where the entire tumor is removed in one piece) is often not achieved using conventional cap EMR. Other techniques, developed in Japan, include the application of different types of knife such as the insulated-tip instrument. We report our preliminary experience of the use of this knife, in conjunction with other techniques, in attempting en bloc resection of early mucosal cancers and adenomas and in the removal of submucosal tumors (SMTs) of the upper gastrointestinal tract. PATIENTS AND METHODS: A total of 37 patients (26 men, 11 women, age range 53 - 86) were included in the study; 23 patients had 24 mucosal lesions amenable to EMR, and 14 patients had SMTs shown on endosonography to spare the muscularis propria. Lesions were located in the esophagus (n = 13), the stomach (n = 24), and the duodenum (n = 1); 40 % of the mucosal lesions were 20 mm or larger (mean size 18mm), whereas the mean size of the submucosal lesions was 23 mm. After submucosal saline injection, circumcision and dissection of the mucosal lesions was attempted with the aim of achieving en bloc resection. For SMTs, cap mucosectomy of the overlying mucosa was done first, and the tumors were then freed using saline injection, and finally resected using snare polypectomy. RESULTS: The strict aim of the study, i. e. complete tumor removal in a single piece, was achieved in only 25 % of the mucosal lesions (some failures were due to unrecognized submucosal infiltration) and 36 % of the SMTs. When a more liberal definition of success was assumed, this rate increased to 65 % for mucosal lesions (piecemeal, no tumor found at surgery or follow-up endoscopy with biopsy) and 79 % for SMTs (piecemeal). No severe complications necessitating surgery or leading to major morbidity occurred. However, clinically significant complications were found in six patients (minor perforation managed conservatively (n = 1), severe pain without perforation (n = 1), bleeding requiring reintervention (n = 3), and aspiration (n = 1)). CONCLUSIONS: Although we are convinced that methods of achieving en bloc resection of mucosal cancers and SMTs must be pursued, the insulated-tip knife in conjunction with conventional endoscopes still has limitations. Innovative endoscope design (double-channel scopes) as well as the development of new accessories will help to overcome the current limitations and further promote endoscopic tumor resection.

Adenoma↗
PubMed2004

Valid symptom reporting at upper endoscopy in a random sample of the Swedish adult general population: the Kalixanda study.

BACKGROUND: Upper oesophagogastroduodenoscopy is considered to be the gold standard for upper gastrointestinal disease assessment, but is currently seldom used in epidemiological studies. One concern is that the procedure may bias sampling among volunteers in a general adult population. The aim of this study was to explore whether the procedure affects symptom reporting. METHODS: A random sample of 3000 adults aged 20-81 years (mean age 50.4), from two Swedish municipalities (n=21,610) was surveyed using a validated postal questionnaire (the Abdominal Symptom Questionnaire) assessing gastrointestinal symptoms. A subsample of the responders was invited, in random order, to undergo an upper endoscopy and repeated symptom reporting using the same questionnaire, as well as a serology test for Helicobacter pylori. RESULTS: The response rate to the initial questionnaire was 74.2% and the participation rate for those eligible for the upper endoscopy was 73.3% (n = 1001, mean age 54.0 years, 48.8% male). No major social or symptom sampling error was encountered from the selection process, with the exception of an excess of symptom reporters among the youngest subjects. The prevalence of reflux symptoms, dyspeptic symptoms and irritable bowel symptoms was 40%, 37.6% and 29.6%, respectively, which is relatively high, but in no way extreme. CONCLUSIONS: The upper endoscopy survey strategy was successful. The response rate was high and there was no major selection bias of clinical relevance. The cohort selected for this study appears to be representative of the general Swedish adult population.

Adult↗
PubMed2004

Accuracy of staging in early oesophageal cancer using high resolution endoscopy and high resolution endosonography: a comparative, prospective, and blinded trial.

BACKGROUND AND AIMS: The increasing use of endoscopic resection for curative treatment of early oesophageal cancers requires accurate staging before therapy. In a prospective blinded trial, we compared staging of early oesophageal carcinoma using high resolution endoscopy (HR-E) with staging using high resolution endosonography (HR-EUS). PATIENTS AND METHODS: A total of 100 patients (89 men, 11 women; mean age 63.9 (10.8) years (range 31-91)) with a suspicion of early oesophageal adenocarcinoma (n = 81) or squamous cell carcinoma (n = 19) were enrolled in the study. After endoscopic staging with high resolution video endoscopy by two experienced endoscopists, HR-EUS was performed by an experienced endosonographer who was blinded to the endoscopic assessment. Results of the staging examinations were correlated with the histology of the resected tumours. RESULTS: Overall rates for accuracy of the endoscopic and endosonographic staging were 83.4% and 79.6%, respectively. Sensitivity for mucosal tumours (n = 68) was more than 90% (EUS 91.2%, endoscopy 94.1%) while sensitivity for submucosal tumours (n = 25) was lower, at 48% for EUS and 56% for endoscopic staging. A combination of the two techniques increased the sensitivity for submucosal tumours to 60%. Submucosal tumours in the tubular oesophagus were significantly better staged with HR-EUS than submucosal tumours close to the oesophagogastric junction (10/11 v 2/14; p<0.001). Tumours infiltrating the second and third submucosal layers were also more correctly diagnosed than tumours with slight infiltration of the first submucosal layer (sm1). CONCLUSIONS: The overall diagnostic accuracy of both HR-E and HR-EUS with a 20 MHz miniprobe in early oesophageal cancer was high (approximately 80%), with no significant differences between the two techniques. HR-E and HR-EUS provide a high level of diagnostic accuracy for mucosal tumours and submucosal tumours located in the tubular part of the oesophagus. With submucosal tumours located at the oesophagogastric junction or with infiltration of the first third of the submucosa however, the diagnostic accuracy of both techniques is not yet satisfactory.

Adenocarcinoma↗
PubMed2004

Maintaining remission of ulcerative colitis with the probiotic Escherichia coli Nissle 1917 is as effective as with standard mesalazine.

BACKGROUND AND AIMS: Evidence exists for the pathogenic role of the enteric flora in inflammatory bowel disease. Probiotics contain living microorganisms which exert health effects on the host. We compared the efficacy in maintaining remission of the probiotic preparation Escherichia coli Nissle 1917 and established therapy with mesalazine in patients with ulcerative colitis. PATIENTS AND METHODS: In total, 327 patients were recruited and assigned to a double blind, double dummy trial to receive either the probiotic drug 200 mg once daily (n = 162) or mesalazine 500 mg three times daily (n = 165). The study lasted for 12 months and patients were assessed by clinical and endoscopic activity indices (Rachmilewitz) as well as by histology. The primary aim of the study was to confirm equivalent efficacy of the two drugs in the prevention of relapses. RESULTS: The per protocol analysis revealed relapses in 40/110 (36.4%) patients in the E coli Nissle 1917 group and 38/112 (33.9%) in the mesalazine group (significant equivalence p = 0.003). Subgroup analyses showed no differences between the treatment groups in terms of duration and localisation of disease or pretrial treatment. Safety profile and tolerability were very good for both groups and were not different. CONCLUSIONS: The probiotic drug E coli Nissle 1917 shows efficacy and safety in maintaining remission equivalent to the gold standard mesalazine in patients with ulcerative colitis. The effectiveness of probiotic treatment further underlines the pathogenetic significance of the enteric flora.

Adult↗
PubMed2004

Long term outcome of patients with gastric marginal zone B cell lymphoma of mucosa associated lymphoid tissue (MALT) following exclusive Helicobacter pylori eradication therapy: experience from a large prospective series.

BACKGROUND: Helicobacter pylori plays a decisive role in the pathogenesis of gastric marginal zone B cell lymphoma of mucosa associated lymphoid tissue (MALT), and eradication therapy has become a widely accepted initial treatment of stage I disease. OBJECTIVE: To determine the long term outcome of patients undergoing exclusive H pylori eradication therapy. DESIGN: A prospective series of patients with newly diagnosed marginal zone B cell lymphoma of MALT. SETTING: Multicentre study in Germany and Austria. PATIENTS: Ninety five patients; 90 of these (five lost to follow up) with a mean age of 54.3 (27-85) years were followed up for at least 12 months. INTERVENTION: Complete staging work up revealing stage I disease and H pylori infection. Patients received triple therapy (OMC: omeprazole 20 mg twice daily, metronidazole 400 mg twice daily, and clarithromycin 250 mg twice daily; or OAC: omeprazole 20 mg twice daily, amoxycillin 1000 mg twice daily, and clarithromycin 500 twice daily) for one week. RESULTS: Median follow up was 44.6 (12-89) months. H pylori was successfully eradicated in 88 patients (98%); in two patients eradication therapy failed. Long term outcome was characterised by complete regression of lymphoma in 56 patients (62%), minimal residual disease in 17 patients (18%), partial remission in 11 patients (12%), no change in four patients (4%), and progressive disease in two patients (2%). Four patients with complete remission relapsed after 6, 8, 8, and 15 months, one revealing reinfection by H pylori. Regression rate was higher in stage I1 disease compared with stage I2, as diagnosed by endoscopic ultrasound. CONCLUSION: The majority of patients with low grade gastric MALT lymphoma treated by exclusive H pylori eradication have a favourable long term outcome, offering a real chance of cure.

Adult↗
PubMed2004

What parameters are relevant for the histological diagnosis of gastroesophageal reflux disease without Barrett's mucosa?

BACKGROUND/AIMS: There are still ongoing controversies as to which histological parameters allow the diagnosis of gastroesophageal reflux disease (GERD). The aim of the present analysis was to relate histological changes of the esophageal squamous epithelium to different severities of GERD. METHODS: Data were obtained from patients participating in the ProGERD study, who had either erosive reflux disease (ERD, n = 3,245) or non-erosive reflux disease (NERD, n = 2,970). 1,475 patients fulfilled our requirement of having complete biopsy data from two sites (2 cm above the z-line and at the z-line). Changes in the squamous epithelium were assessed by measuring the thickness of the basal cell layer and elongation of the papillae as a percentage of the whole epithelial thickness and counting interepithelial inflammatory cells. RESULTS: The most useful parameters for histological assessment of GERD (given as means, 2 cm above the z-line and at the z-line, respectively) were elongation of the papillae: NERD 40.7 and 48.9%; ERD 46.1 and 54.9% and basal cell hyperplasia: NERD 12.7 and 17.9%; ERD 15.7 and 23.0%. The occurrence of intraepithelial lymphocytic infiltrates, however, is dependent on the severity of GERD, and they are more common than neutrophilic and eosinophilic granulocytes. CONCLUSION: This study shows that both NERD and ERD can be diagnosed histologically if biopsies are obtained from the distal esophagus or from the z-line. Intraepithelial inflammatory cells are rare and show a high specificity, but very low sensitivity.

Adult↗
PubMed2004

Radial distribution of dilated intercellular spaces of the esophageal squamous epithelium in patients with reflux disease exhibiting discrete endoscopic lesions.

INTRODUCTION: Dilatation of intercellular spaces of the esophageal squamous epithelium has been suggested as a marker of early acid reflux-induced damage. This change is a potentially useful addition to histomorphological changes that represent so called minimal endoscopic lesions. We have assessed dilatation of intercellular spaces with regard to: (1) interobserver variability, and (2) whether the incidence of this varies between 'red streaks' and the adjacent normal looking squamous epithelium. METHODS: Esophageal biopsies from 44 patients with chronic gastro-esophageal reflux (GERD) were evaluated. At endoscopy, these patients had one or more red streaks on the tops of the mucosal folds in the distal esophagus. Biopsies were taken from the red streaks and from the normal-appearing mucosa 1 cm lateral to the red streaks. Biopsies were assessed in a blinded fashion by two independent pathologists (MV & RF). Criteria for assessing intercellular space dilatation were evaluated and agreed on prior to the study. RESULTS: Good interobserver agreement was recorded (kappa = 0.82 at the streaks and 0.77 for the control tissues) for absence/presence of intercellular space dilatation. Red streak and control biopsies differed significantly (p = 0.0001), with respect to presence of dilated intercellular spaces, with 90.5 % of the former demonstrating this as present compared to 56.1% in the controls. CONCLUSION: This study supports the concept that esophageal mucosal minimal changes due to reflux is localised and that dilatation of intercellular spaces is an early sign of reflux-induced epithelial damage. The low interobserver variability in the assessment of intercellular space dilatation suggests that this may be a useful variable for assessment of early signs of acid-reflux induced damage to the squamous epithelium of the esophagus by use of light microscopy.

Biopsy↗
PubMed2003

Favourable effect of regular intake of fermented milk containing Lactobacillus johnsonii on Helicobacter pylori associated gastritis.

BACKGROUND: Lactobacillus johnsonii (Lj1) had an in vitro and in vivo inhibitory effect on Helicobacter pylori. Fermented milk containing Lj1 (LC1), coadministered with antibiotics had a favourable effect on H. pylori gastritis. AIM: Evaluate the effect of LC1 intake without antibiotics on H. pylori gastritis. METHODS: Fifty H. pylori positive healthy volunteers were randomised in a double-blind study to LC1 or placebo. Gastric biopsies from the antrum and corpus were obtained before, and after 3 and 16 weeks of treatment, for histology and quantitative cultures. RESULTS: Severity and activity of antral gastritis was reduced after 16-week LC1 intake (pretreatment and 16-week inflammatory cell score: 6.0 +/- 0.8 vs. 5.3 +/- 0.1; P=0.04). H. pylori density decreased in the antrum after LC1 intake (3-week: 4.4 +/- 0.6; 16-week: 4.3 +/- 0.5 log10 colony forming units (cfu) vs. pretreatment 4.5 +/- 0.4 log10 cfu; P=0.04, respectively). Mucus thickness increased after 16 weeks of LC1 consumption (change of mucus thickness with LC1 and placebo in the antrum: 0.6 +/- 1.3 vs. -0.2 +/- 1.0, P=0.01; in the corpus: 0.3 +/- 1.1 vs. -0.6 +/- 1.5, P=0.03). CONCLUSION: LC1 intake had a favourable, albeit weak, effect on H. pylori associated gastritis, particularly in the antrum. Regular ingestion of fermented milk containing L. johnsonii may reduce the risk of developing disorders associated with high degrees of gastric inflammation and mucus depletion.

Adolescent↗
PubMed2003

Esomeprazole-based one-week triple therapy with clarithromycin and metronidazole is effective in eradicating Helicobacter pylori in the absence of antimicrobial resistance.

AIM: This study aimed to investigate the effectiveness of a one-week triple therapy with esomeprazole, clarithromycin and metronidazole for eradication of Helicobacter pylori infection in the absence of antimicrobial resistance. METHODS: Patients testing positive for H. pylori susceptible to metronidazole and clarithromycin (E-test) were randomized to receive a one-week regimen with either esomeprazole 2 x 20 mg or omeprazole 2 x 20 mg in combination with clarithromycin 2 x 250 mg and metronidazole 2 x 400 mg. Follow-up endoscopy with histology and culture and/or rapid urease test was performed 4-8 weeks after the end of treatment. RESULTS: Eighty patients were randomized. Helicobacter pylori infection was cured in 38/39 patients of the esomeprazole group and 31/33 patients of the omeprazole group (per protocol 97.4% (95% confidence interval [CI], 86.2-99.9), 93.7% (95% CI, 79.2-99.2), P=0.59); intention-to-treat 90.4% (95% CI: 77.4-97.3), 81.6% (95% CI: 65.7-92.3), respectively. No major side effects occurred. Minor side effects occurred in eight (20%) and six (23%) patients during esomeprazole and omeprazole therapy, respectively. Post-treatment susceptibility testing revealed resistance to both metronidazole and clarithromycin in two of the three patients who failed. CONCLUSION: We conclude that esomeprazole, clarithromycin and metronidazole as one-week triple therapy is effective for eradication of H. pylori in the absence of antimicrobial resistance.

Adult↗
PubMed2003

Quality of life in relation to symptoms in patients with gastro-oesophageal reflux disease-- an analysis based on the ProGERD initiative.

AIMS: To determine the impact of gastro-oesophageal reflux disease (GERD) on the quality of life, to assess changes in the quality of life during treatment with esomeprazole and to define factors that can predict these changes. METHODS: Patients with GERD (n=6215) were included in a prospective cohort study (ProGERD). All patients underwent endoscopy and received esomeprazole. At baseline and after 2 weeks of treatment, symptoms and quality of life were assessed. Factors that influenced changes in the quality of life were determined by multiple regression analyses. RESULTS: At baseline, the quality of life in GERD patients was lower than that in the general population, and was similar to that in patients after acute coronary events. No differences in symptoms or quality of life were observed between the subgroups of patients with non-erosive GERD, erosive GERD and Barrett's oesophagus. After treatment with esomeprazole, the symptoms and quality of life were improved in all subscales within 2 weeks (P<0.001). The mean score of the disease-specific quality of life instrument (Quality of Life in Reflux and Dyspepsia Patients) increased from 4.6 to 6.2 points, representing a highly relevant clinical improvement. The generic quality of life (SF-36) reached levels similar to those in the general population, but, again, no difference was found between the three different subgroups of GERD patients. The main factors associated with an improvement in the quality of life after treatment were symptom relief, severe erosive reflux disease, absence of extra-oesophageal disorders, avoidance of non-steroidal anti-inflammatory drug intake and positive Helicobacter pylori status. CONCLUSIONS: GERD causes a significant impairment in the quality of life that can be attenuated or normalized within a time period as short as 2 weeks by treatment with esomeprazole. These findings were similar across the whole GERD patient spectrum.

Adult↗
PubMed2003

Clonal relationship in multifocal non-Hodgkin's lymphoma of mucosa-associated lymphoid tissue (MALT).

To elucidate the progression of gastric marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type, we analyzed a case presenting simultaneously with MALT lymphoma of the stomach and lung, and a gastric high-grade diffuse large lymphoma. The rearranged immunoglobulin heavy chain (IgH) variable regions were analyzed using a polymerase chain reaction (PCR)-based assay. Clonal relationship was shown between the gastric high-grade and the pulmonary low-grade lymphoma. The gastric MALT lymphoma was not related to the other manifestations. Translocation t(11;18) was not detected in the gastric high-grade lymphoma. MALT lymphomas at various locations and with different histologies may derive from a common precursor cell. Lymphomas at identical sites may have different stem cells.

Aged↗
PubMed2003

Histopathological diagnosis of Barrett's mucosa and associated neoplasias: results of a consensus conference of the Working Group for Gastroenterological Pathology of the German Society for Pathology on 22 September 2001 in Erlangen.

There are a number of difficulties regarding the diagnosis of Barrett's mucosa and the varying grades of neoplasia that may be associated with it. It was, therefore, the aim of a consensus conference of the Working Group for Gastroenterological Pathology within the German Society of Pathology to achieve standardisation regarding the following issues: definition and diagnostic criteria for Barrett's mucosa and its discrimination from intestinal metaplasia of the cardia, diagnostic criteria for intraepithelial neoplasia, number of biopsies necessary to establish the diagnosis, significance of additional immunohistochemical and/or molecular methods as well as importance of a second opinion in the diagnosis of intraepithelial neoplasia.

Barrett Esophagus↗
PubMed2003

Helicobacter pylori eradication is beneficial in the treatment of functional dyspepsia.

AIM: To assess whether the eradication of Helicobacter pylori leads to long-term relief of symptoms in functional dyspepsia. METHODS: Eight hundred patients with functional dyspepsia were randomized to receive double-blind treatment with twice-daily 30 mg lansoprazole, 1000 mg amoxicillin and 500 mg clarithromycin for 7 days (L30AC), twice-daily 15 mg lansoprazole, 1000 mg amoxicillin and 500 mg clarithromycin for 7 days (L15AC), or once-daily 15 mg lansoprazole for 14 days (LP). Dyspepsia and reflux symptoms were monitored for 12 months. RESULTS: In intention-to-treat analysis, the non-ulcer dyspepsia sum score showed a statistically significant benefit in terms of symptom relief in the L30AC group (P = 0.0068) compared with the LP group, but there was no significant difference between the L15AC and LP groups (P = 0.2). When all patients in the two eradication therapy arms were considered together, successful eradication had a significant benefit with regard to the complete absence of symptoms (P < 0.04). H. pylori eradication did not lead to an increase in reflux symptoms. CONCLUSION: This study suggests that H. pylori infection causes dyspeptic symptoms in a subset of patients with functional dyspepsia, and that these patients may obtain long-term symptomatic benefit following H. pylori eradication.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2003

Etiology and therapy of Helicobacter pylori-associated gastric lymphomas.

The WHO separates marginal zone B-cell lymphomas (MZBL) of nodal and extranodal type. Both arise from memory B cells of the marginal zone. Extranodal MZBL of the mucosa-associated lymphatic tissue (MALT) have characteristic features such as homing in epithelial tissue, lymphoepithelial destruction, and a very indolent clinical course. They arise in epithelial tissues normally devoid of lymphatic cells, where the lymphatic tissue was acquired after, for instance, a chronic infection. The best example here is infection of the stomach with Helicobacter pylori ( Hp). Besides the classical association with gastric MALT lymphomas, there have been reports in which an association between Hp and diffuse large B-cell lymphoma (DLBCL) has been observed as well. Consequently, cure of Hp infection resulted in remission induction not only in gastric MALT lymphomas, but also in some patients with very limited stages of DLBCL of the stomach. In addition to the association with Hp, progress has been made with regard to MALT lymphoma biology. Translocation t(1;14) involving the Bcl-10 gene, and translocation t(11;18) involving a novel gene called MLT1, both result in activation of the crucial transcription factor NF-kappaB. These genetic events seem specific in that they have been observed only in MALT lymphomas. Once present, at least the more frequently observed translocation t(11;18) renders cells resistant to cure of Hp infection. Another clinically important question is that in many patients in complete remission after cure of Hp infection, detection of minimal residual disease is positive. Whether these cells are normal memory B cells (with the identical B-cell rearrangement as the original lymphoma clone), or dormant lymphoma cells, is unclear at present. In patients not responding to cure of Hp infection, several treatment options are discussed. MALT lymphomas have opened up a new discussion of lymphoma biology and have thus been called a model disease.

Chromosomes, Human, Pair 1↗