Exocrine and endocrine modulation in common gastric carcinoma

Neuroendocrine differentiation and serotonin expression in oesophageal adenocarcinomas after neoadjuvant therapy: correlation with clinicopathological features and outcome

AIMS

Oesophageal adenocarcinoma (EAC) is a glandular or mucinous epithelial malignancy that can show immunohistochemical evidence of neuroendocrine differentiation (NED) and express the hormone serotonin. The objective of this study was to correlate the presence of NED and serotonin with clinicopathological characteristics and patient outcome after neoadjuvant chemoradiation.

METHODS AND RESULTS

A retrospective cohort of patients treated between 2002 and 2021 was established and included 218 oesophagectomy specimens with residual tumour. Representative full-face sections of tumour were stained for synaptophysin, chromogranin-A and serotonin by immunohistochemistry, and staining results were correlated with disease-free survival (DFS) and overall survival (OS). In total, 129 (59%) tumours showed evidence of NED, defined as immunohistochemical expression of synaptophysin or chromogranin-A, while 40 (18%) showed evidence of NED and expressed serotonin. Patients with neuroendocrine-positive tumours had significantly shorter median OS compared to those with neuroendocrine-negative tumours (22.5 versus 48.8 months, P = 0.006), but similar median DFS (13.3 versus 17.8 months, P = 0.34). Using Cox regression, the association between NED and OS was significant in univariate [hazard ratio (HR) = 1.68, 95% confidence interval (CI) = 1.16-2.45] and multivariate (HR = 1.65, 95% CI = 1.08-2.52) analysis. Patients with serotonin-expressing tumours had similar median OS (21.7 versus 25.9 months, P = 0.24) and DFS (7.3 versus 15.6 months, P = 0.12) compared to those with NED but lacking serotonin. Using Cox regression, serotonin expression was associated with reduced OS in univariate (HR = 1.62, 95% CI = 1.06-2.47) but not multivariate (HR = 1.03, 95% CI = 0.64-1.65) analysis.

CONCLUSIONS

Our findings support NED as independent predictor of OS in EAC after neoadjuvant chemoradiation. While a subset of tumours with NED expressed serotonin, this did not provide additional prognostic information.

Prognostic Threshold of Neuroendocrine Differentiation in Gastric Carcinoma: a Clinicopathological Study of 945 Cases

Purpose

The significance of neuroendocrine differentiation (NED) in gastric carcinoma (GC) is controversial, leading to ambiguous concepts in traditional classifications. This study aimed to determine the prognostic threshold of meaningful NED in GC and clarify its unclear features in existing classifications.

Materials and Methods

Immunohistochemical staining for synaptophysin, chromogranin A, and neural cell adhesion molecule was performed for 945 GC specimens. Survival analysis was performed using the log-rank test and univariate/multivariate models with percentages of NED (P_NED) and demographic and clinicopathological parameters.

Results

In total, 275 (29.1%) cases were immunoreactive to at least 1 neuroendocrine (NE) marker. GC-NED was more common in the upper third of the stomach. P_NED, and Borrmann's classification and tumor, lymph node, metastasis stages were independent prognostic factors. The cutoff P_NED was 10%, beyond which patients had significantly worse outcomes, although the risk did not increase with higher P_NED. Tumors with ≥10% NED tended to manifest as Borrmann type III lesion with mixed/diffuse morphology and poorer histological differentiation; the NE components in this population mainly grew in insulae/nests, which differed from the predominant growth pattern (glandular/acinar) in GC with <10% NED.

Conclusions

GC with ≥10% NED should be classified as a distinct subtype because of its worse prognosis, and more attention should be paid to the necessity of additional therapeutics for NE components.

Benign glandular downgrowth in gastric neuroendocrine neoplasms: a potential mimic of composite tumour

AIMS

We have observed glandular downgrowth in some gastric neuroendocrine tumours (NETs), in which nonneoplastic appearing gastric glands are admixed with submucosal neuroendocrine nests, that could potentially be confused with composite tumours.

METHODS AND RESULTS

We reviewed 68 gastric NETs with at least submucosal invasion, and evaluated associations between glandular downgrowth, clinical parameters (age, gender, NET setting) and tumour characteristics (size, depth of invasion, grade). Controls included 45 duodenal NETs. Glandular downgrowth was present in 28 (41%) gastric NETs but only 2 (4.4%) duodenal NETs (P < 0.0001). It was not related to age, gender, hypergastrinemia (downgrowth present in 43% of NETs arising in autoimmune gastritis, 41% of Zollinger-Ellison syndrome, 36% of sporadic NETs), tumour size, depth of invasion, or grade. Glandular downgrowth was confined to the submucosa even though 12 (18%) gastric NETs invaded muscularis propria. Submucosal gastric glands (pyloric type in 79%, intestinal in 50%, fundic in 29%) showed metaplastic changes similar to overlying mucosa, were usually mitotically inactive (64% of cases lacked mitotic figures), were geographically restricted to the NET, and never metastasized.

CONCLUSIONS

Our findings support the frequent occurrence and nonneoplastic nature of glandular downgrowth in gastric NETs, which should not be mistaken for composite tumours.

High expression of DEK predicts poor prognosis of gastric adenocarcinoma

BACKGROUND

DEK, as an oncoprotein, plays an important role in cancer development and progression. This study aimed to investigate the clinicopathological significance of DEK overexpression in patients with gastric cancer.

MATERIALS AND METHODS

The expression of DEK protein was evaluated by immunohistochemical (IHC) staining of 172 gastric cancer samples with complete clinicopathological features, and the correlation between DEK expression and clinicopathological features was examined. Survival rates were also calculated using the Kaplan-Meier method in gastric cancer patients with complete survival data.

RESULTS

DEK protein showed a strictly nuclear staining pattern in gastric cancers with IHC and immunofluorescence. The strongly positive rate of DEK protein was 60.5% (104/172) in gastric cancers, which was significantly higher than that in either gastric dysplasia (19.4%, 7/36) or adjacent normal mucosa (0%, 0/27). DEK expression in gastric cancer correlated to tumor size, differentiation, clinical stage, disease-free survival, and overall survival rates. Further analysis showed that patients with early-stage gastric cancer and high DEK expression had shorter disease-free survival and overall survival duration than those with low DEK expression.

CONCLUSION

High level of DEK protein expression predicts the poor prognosis of patients with gastric cancer. DEK expression might be potentially used as an independent effective biomarker for prognostic evaluation of gastric cancers.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5050145571193097.

The regulation of gastric acid secretion - clinical perspectives

The purpose of this review, based upon 40 years of research, is to clear old controversies. The gastric juice is a strong acid with active enzymes (pepsin and lipase); ideal for killing swallowed microorganisms. Totally isolated rat stomach and histamine determination. Human gastric carcinomas were examined for ECL cell differentiation because tumours found in rodents after dosing with inhibitors of acid secretion were reclassified to be of ECL cell origin. The gastrin receptor is localized to the ECL cell only, where gastrin stimulates the function and growth. Drug-induced hypo-acidity induces hypergastrinaemia and ECL cell hyperplasia responsible for rebound acid hypersecretion. Every condition with long-term hypergastrinaemia disposes to ECL cell neoplasia. In man, both atrophic gastritis and gastrinoma lead to ECL cell carcinoids. Proton pump inhibitors induce hypergastrinaemia with ECL cell hyperplasia and ECL cell carcinoids that disappear when stopping treatment. The gastrin antagonist netazepide induces regression of ECL cell carcinoids due to atrophic gastritis. Human gastric carcinomas of diffuse type, particularly the signet-ring subtype, show ECL cell differentiation, suggesting involvement of gastrin in the carcinogenesis. Helicobacter pylori (Hp) causes gastritis and peptic ulcer, and when infecting the antrum only gives a slight hypergastrinaemia with acid hypersecretion predisposing to duodenal ulcer, but protecting from gastric cancer. When Hp infection spreads to oxyntic mucosa, it induces atrophy, reduced acid secretion and marked hypergastrinaemia and cancer.It is remarkable that the interaction between Hp and gastrin may explain the pathogenesis of most diseases in the upper gastrointestinal tract.