Dysplasia east and west

Histologic heterogeneity and syndromic associations of non-ampullary duodenal polyps and superficial mucosal lesions

BACKGROUND

Duodenal polyps and superficial mucosal lesions (DP/SMLs) are poorly characterised.

AIMS

To describe a series of endoscopically-diagnosed extra-ampullary DPs/SMLs.

METHODS

This is a retrospective study conducted in a tertiary referral Endoscopy Unit, including patients who had DPs or SMLs that were biopsied or removed in 2010-2019. Age, gender, history of familial polyposis syndromes, DP/SML characteristics were recorded. Histopathological, immunohistochemical and molecular analyses were performed.

RESULTS

399 non-ampullary DP/SMLs from 345 patients (60.6% males; median age 67 years) were identified. Gastric foveolar metaplasia represented the most frequent histotype (193 cases, 48.4%), followed by duodenal adenomas (DAs; 77 cases, 19.3%). Most DAs (median size 6 mm) were sessile (Paris Is; 48%), intestinal-type (96.1%) with low-grade dysplasia (93.5%). Among syndromic DAs (23%), 15 lesions occurred in familial adenomatous polyposis 1, two were in MUTYH-associated polyposis and one was in Peutz-Jeghers syndrome (foveolar-type, p53-positive, low-grade dysplasia). Only one (3.3%) tubular, low-grade DA showed mismatch repair deficiency (combined loss of MLH1 and PMS2, heterogeneous MSH6 expression), and it was associated with a MLH1 gene germline mutation (Lynch syndrome).

CONCLUSION

DPs/SMLs are heterogeneous lesions, most of which showing foveolar metaplasia, followed by low-grade, intestinal-type, non-syndromic DAs. MMR-d testing may identify cases associated with Lynch syndrome.

The current spectrum of gastric polyps: a 1-year national study of over 120,000 patients

OBJECTIVES

To use a large pathology database (Caris Diagnostics) to analyze the frequency and associations of gastric polyps in a nationwide US population.

METHODS

A total of 121,564 esophagogastroduodenoscopy (EGD) procedures from private practices in 36 states in the Caris Diagnostics database from 1 April 2007 to 31 March 2008 were searched for the endoscopic designations of polyp, nodule, and mass, and for the pathological diagnoses that commonly present as gastric polyps. Pertinent demographic data, clinical indications for EGD, and information regarding Helicobacter pylori infection, reactive gastropathy, chronic inactive gastritis, and intestinal metaplasia were also obtained.

RESULTS

A total of 78,909 of the 121,564 patients who underwent EGD had gastric biopsies. The prevalence of gastric polyps in the EGD population was 6.35%; 77% were fundic gland polyps, 17% hyperplastic polyps/polypoid foveolar hyperplasia, 0.69% adenomas, and 0.1% inflammatory fibroid polyps. Malignant neoplasms were slightly >2%. None of the benign gastric polyps had a significant positive association with concurrent H. pylori infection; intestinal metaplasia was detected in the background of 52.2% of carcinoids, 29.6% of adenomas, 20.1% of xanthomas, and 13% of adenocarcinomas and hyperplastic polyps. Adenomas were rarely associated with synchronous adenocarcinomas.

CONCLUSIONS

The relative prevalence of fundic gland polyps in this population was much higher than that reported earlier, most likely because of the widespread use of proton pump inhibitors. H. pylori- and atrophy-associated polyps, including adenomas, were less common than in earlier series.

[Dysplasia in glandular digestive tissues: new concepts, new classifications]

The term of dysplasia is currently used to designate morphological alterations, identifiable at microscopic examination, revealing the existence of an unequivocally neoplastic process, at an early, non-invasive, stage of its natural history. The pathologist bears the full responsibility for the diagnosis of dysplasia, based on a broad spectrum of cytological and architectural abnormalities. It is important to grade the severity of the dysplastic lesions, in order to help guide clinical management and choose the therapeutic strategy. The Vienna classification, proposed in 2000 as a compromise between the Western and Japanese concepts, is now used for classification and grading of digestive epithelial dysplasia. The major advantages of the Vienna classification are the use of uniform terminology worldwide, achievement of good diagnostic reproducibility between pathologists and clear and consensual clinical consequences. Its use is strongly supported by the recent international recommendations.

Updated diagnostic criteria on gastric epithelial dyspalsia

Large discrepancies exist between Eastern and Western countries in the diagnostic criteria for gastric epithelial dysplasia. With the purpose of a worldwide-accepted terminology and classification of precancerous lesions, Padova and Vienna classifications are established and reach a consensus that epithelial dysplasia is the earliest visible manifestation of neoplasia and the stage at which invasion has not yet occurred. So the primary term 'dysplasia' is confusing and misleading as gastric precancerous lesion. With more insight into dysplasia, new directions will be found to explore the pathogenesis, reversibility and therapy of dysplasia.

One more dysplasia

Gastric epithelial dysplasia is the earliest visible stage of neoplasia. Most histopathologists can recognize or at least suspect it, and a set of established clinical responses follow its detection. In contrast, proliferations and dysplastic changes of gastric endocrine cells are difficult to identify and generally neglected. Such changes are known to predispose to the development of carcinoid tumours and usually arise in patients with corpus-predominant atrophic gastritis and elevated gastrin levels. A report in this issue suggests that patients with dysplasia of the enterochromaffin-like cells have a much greater risk of developing carcinoid tumours than previously suspected. These carcinoids (known as type I) tend to have an indolent course, are almost never functional and have a favourable prognosis; nevertheless, they need to be detected and excised endoscopically. Because of the small numbers of patients in this series and the relatively short follow-up time of the study, it would be premature to issue guidelines on the long-term management of patients with atrophic gastritis and hypergastrinaemia. However, it is incumbent on clinical researchers with access to well-defined cohorts, such as the one studied here, to continue the follow-up studies that will lead to a more precise definition of risk and to the development of usable evidence-based clinical strategies.

Review article: pre-neoplastic states of the gastric mucosa--a practical approach for the perplexed clinician

The sequence leading to gastric cancer can be schematically reduced to Helicobacter pylori infection-chronic gastritis-atrophy-intestinal metaplasia-dysplasia-neoplasia. Although clinicians have not yet developed a uniform approach to the treatment of gastritis (when should H. pylori infection be treated?), the entity itself is not the subject of controversy. All other lesions are still the focus of debate. There are no guidelines for the management of patients with intestinal metaplasia; pathologists are still searching for universal diagnostic criteria for atrophic gastritis; dysplasia and early neoplasia have elicited scientific diatribes between Japanese and Western pathologists. Amidst such controversies and in the absence of guidelines to regulate the management of gastric lesions, the responsibility to provide sensible clinical advice is often bestowed upon pathologists. This review discusses whether pathologists have access to sufficient evidence to provide the requested advice, and whether a consensus on the management of gastric "pre-neoplastic" states is within reach. We conclude that, although many sensible and useful definitions, criteria and classifications are being generated, the final decision on how to manage the individual patient with gastric lesions will continue to be based on the communication between pathologist and clinician.