Person:

Lauwers, Gregory Y.

Gastric intestinal metaplasia can display cytoarchitectural atypia that falls short of qualifying for dysplasia but can be classified as indefinite for dysplasia. Yet few studies have evaluated the prevalence, the morphologic, and biologic characteristics of this variant. Out of a cohort of 554 biopsies with chronic atrophic gastritis and/or dysplasia, we categorized the cases as either (1) simple intestinal metaplasia; (2) intestinal metaplasia with hyperplasia; (3) intestinal metaplasia with basal gland atypia; and (4) gastric dysplasia. The relationship between the subtypes and various clinicopathologic features, mucin immunophenotypes, and biologic characteristics was evaluated. The final cohort consisted of 424 cases of simple intestinal metaplasia, 93 intestinal metaplasia with hyperplasia, 16 intestinal metaplasia with basal gland atypia, and 21 gastric dysplasia. Intestinal metaplasia with basal gland atypia had a prevalence of 2.8% and similar to gastric dysplasia, 3.7%. Both of these lesions were similar in body/fundus distribution (12.5%) and paucity of goblet cells (68.8%). Intestinal metaplasia with basal gland atypia and gastric dysplasia seem to share some biologic similarities but with a lower frequency of alpha-methylacyl-CoA racemase expression (25% versus 62%), p53 expression (6.3% versus 47.6%), and increased Ki-67 index on surface/pit and isthmus in intestinal metaplasia with basal gland atypia. Alternatively, simple intestinal metaplasia and intestinal metaplasia with hyperplasia did not differ statistically with regard to the various characteristics evaluated. We concluded that gastric intestinal metaplasia can be divided into 2 broad categories that are readily defined by cytoarchitectural and biologic characteristics. Based on the characteristics of intestinal metaplasia with basal gland atypia and in keeping with others, we confirm that this subtype could represent a preneoplastic lesion that needs further evaluation.

BACKGROUND: Gastric hyperplastic polyps are the second most common subtype of gastric polyps. There has been an ongoing debate about their precise diagnostic criteria and etiological associations. MATERIALS AND METHODS: A total of 208 gastric polyps that were originally diagnosed as hyperplastic polyps in our department during an 8-year period were reviewed using recently emphasized diagnostic criteria, and their clinicopathologic associations were explored. RESULTS: Only 41 cases were confirmed as hyperplastic polyps, whereas 103 cases (49%) were reclassified as polypoid foveolar hyperplasia, and 64 cases (31%) were diagnosed as gastric mucosal prolapse polyps. Gastric mucosal prolapse polyps were distinguished by basal glandular elements, hypertrophic muscle fibers ascending perpendicularly from the muscularis mucosae, and by thick-walled blood vessels. This hitherto undescribed polyp is more commonly sessile than hyperplastic polyps (P=0.0452) and is found more often in the antropyloric region (P: 0.0053). Only 20.6% of hyperplastic polyps were associated with Helicobacter pylori infection. CONCLUSIONS: Our findings highlight that gastric polypoid lesions that have morphologic similarities may be related to various mechanisms, including inflammatory and prolapse processes. The predominantly antral location of gastric mucosal prolapse polyps, a zone of pronounced peristalsis, suggests that mucosal prolapse plays a role in the development of these common polyps. Evaluation of the prevalence and clinical associations of these distinctive polyps awaits further studies.

AIM: To investigate the clinicopathologic features which predict surgical overall survival in patients with proximal gastric carcinoma involving the esophagus (PGCE). METHODS: Electronic pathology database established in the Department of Pathology of the Nanjing Drum Tower Hospital was searched for consecutive resection cases of proximal gastric carcinoma over the period from May 2004 through July 2009. Each retrieved pathology report was reviewed and the cases with tumors crossing the gastroesophageal junction line were selected as PGCE. Each tumor was re-staged, following the guidelines on esophageal adenocarcinoma, according to the 7th edition of the American Joint Commission on Cancer Staging Manual. All histology slides were studied along with the pathology report for a retrospective analysis of 13 clinicopathologic features, i.e., age, gender, Helicobacter pylori (H. pylori) infection, surgical modality, Siewert type, tumor Bormann's type, size, differentiation, histology type, surgical margin, lymphovascular and perineural invasion, and pathologic stage in relation to survival after surgical resection. Prognostic factors for overall survival were assessed with uni- and multi-variate analyses. RESULTS: Patients' mean age was 65 years (range: 47-90 years). The male: female ratio was 3.3. The 1-, 3- and 5-year overall survival rates were 87%, 61% and 32%, respectively. By univariate analysis, age, male gender, H. pylori, tumor Bormann's type, size, histology type, surgical modality, positive surgical margin, lymphovascular invasion, and pT stage were not predictive for overall survival; in contrast, perineural invasion (P = 0.003), poor differentiation (P = 0.0003), > 15 total lymph nodes retrieved (P = 0.008), positive lymph nodes (P = 0.001), and distant metastasis (P = 0.005) predicted poor post-operative overall survival. Celiac axis nodal metastasis was associated with significantly worse overall survival (P = 0.007). By multivariate analysis, ≥ 16 positive nodes (P = 0.018), lymph node ratio > 0.2 (P = 0.003), and overall pathologic stage (P = 0.002) were independent predictors for poor overall survival after resection. CONCLUSION: Patients with PGCE showed worse overall survival in elderly, high nodal burden and advanced pathologic stage. This cancer may be more accurately staged as gastric, than esophageal, cancer.

Background: The genetics of advanced biliary tract cancers (BTC), which encompass intra- and extra-hepatic cholangiocarcinomas as well as gallbladder carcinomas, are heterogeneous and remain to be fully defined. Methods: To better characterize mutations in established known oncogenes and tumor suppressor genes we tested a mass spectrometric based platform to interrogate common cancer associated mutations across a panel of 77 formalin fixed paraffin embedded archived BTC cases. Results: Mutations among three genes, KRAS, NRAS and PIK3CA were confirmed in this cohort. Activating mutations in PIK3CA were identified exclusively in GBC (4/32, 12.5%). KRAS mutations were identified in 3 (13%) intra-hepatic cholangiocarcinomas and 1 (33%) perihillar cholangiocarcinoma but were not identified in gallbladder carcinomas and extra-hepatic cholangiocarcinoma. Conclusions: The presence of activating mutations in PIK3CA specifically in GBC has clinical implications in both the diagnosis of this cancer type, as well as the potential utility of targeted therapies such as PI3 kinase inhibitors.

Aims:  To compare the clinical and pathological features of gastro-oesophageal junction (GEJ) carcinomas in Chinese and American patients. Methods and results:  Eighty consecutive patients with a GEJ carcinoma (43 from mainland China, and 37 from the USA) were evaluated for association with Barrett oesophagus (BO), chronic Helicobacter pylori gastritis, intestinal metaplasia, and outcome. GEJ carcinomas were defined as tumours that were located within 20 mm of, and crossed, the GEJ. Overall, GEJ carcinomas from Chinese patients revealed significantly more frequent location in the proximal stomach, higher pathological stage, larger size, younger patient age, and association with chronic H. pylori gastritis. In contrast, GEJ cancers from American patients showed a strong association with distal oesophageal location, BO, and associated intestinal metaplasia and dysplasia. Pathologically, GEJ carcinomas from American patients were predominantly adenocarcinomas, whereas Chinese patients showed a higher proportion of mucinous, adenosquamous, acinar or neuroendocrine tumours. Overall, 3- and 5-year survival rates were statistically similar between both patient groups, but upon multivariate analysis, Chinese patients showed statistically better survival rates for stage III tumours. Conclusions:  Most GEJ carcinomas in patients from China represent proximal gastric cancers associated with chronic H. pylori gastritis, and BO-associated carcinomas are rare among this patient population.