Clinicopathologic study of neuroendocrine tumors of gastroenteropancreatic tract: a single institutional experience

Ectopic gastric mucosa in the submucosa of the stomach: A case report

Under normal circumstances, gastric mucosa only exists within the stomach. However, in certain situations, gastric mucosal tissue may undergo ectopia, commonly occurring in the esophagus and intestine, with rare occurrences within the stomach itself. A comprehensive literature review was performed to understand the distinct characteristics of ectopic gastric mucosa (EGM) in the stomach and investigate a rare incident of this disease, providing an in-depth analysis of the clinical, histopathologic, and differential diagnostic findings. The case was a 47-year-old man with acid reflux, heartburn, abdominal distension, and diarrhea (5-10 times daily) for >10 years. A gastroscope indicated a submucosal protuberance lesion in the gastric body that felt hard with biopsy forceps. A well-defined nodule under the mucosal muscle was revealed microscopically, composed of epithelial elements and no atypia. Immunohistochemical staining demonstrated similar EGM expression patterns compared with normal gastric mucosa. The present case report highlights the importance of accurate EGM diagnosis and understanding.

Clinicopathological Features of Neuroendocrine Tumors in Gastroenteropancreatic Tract: A Single Center Study

Background: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are a heterogeneous group of tumors with varying biological, functional, and clinical characteristics that develop from the gastroenteropancreatic tract's diffuse neuroendocrine system. The objective of this study is to determine the clinicopathological features of GEP-NETs at our facility.

Methodology: A cross-sectional analysis of 87 biopsies and resection specimens from January 2020 to January 2022 was performed. The histopathological reports as well as patient's demographic and clinic pathological data were obtained. Two pathologists with a special interest in gastroenteropancreatic pathology blindly reviewed all cases. The tumor grade and stage were determined using the WHO classification (2019) and the AJCC TNM system (8th edition). The data were analyzed with SPSS version 22 (IBM Corp., Armonk, NY, USA).

Results: Of the total 87 patients, 49 (56.3%) were male. The age range was 11 to 80 years, with a mean of 45.7±16.4 and the majority (56.3%) were under 50 years. The most frequent symptom was abdominal pain (55.2%). The most common site of GEP-NETs was the appendix (21.8%), followed by the ileum (18.4%), with the majority of tumors being non-functional (96.5%). Furthermore, neuroendocrine tumor (NET) grade 1 accounts for 62% of the total, followed by NET grade 2 (24.1%), neuroendocrine carcinoma (NET) grade 3 (10.3%), and mixed neuroendocrine-non-neuroendocrine neoplasms (MINENs) (3.5%). Synaptophysin was found to be positive in 83.9% cases while Chromogranin A was positive in 39.1%. A pathologic tumor (pT) stage was determined in 47 resection specimens in our study and the most common stage was pT3 (36.1%). Nodal metastasis was found in 25.5% of patients.

Conclusions: According to our study, appendix and ileum were the most common GEP-NETs sites. The tumor site and grade were shown to significantly correlate among the clinicopathological features but there was no discernible correlation between the tumor grade and the gender, age, or pathological tumor (pT) stage.

Clinicopathologic profile of gastroenteropancreatic neuroendocrine neoplasms in a referral center of South India

BACKGROUND

The neuroendocrine system of the gastroenteropancreatic (GEP) region gives rise to unique, heterogeneous malignancies that need a high index of suspicion to make a diagnosis owing to their indolent course.

AIMS

The present study aimed to find the incidence and the differences in the morphologic and immunohistochemical profile of gastroenteropancreatic neuroendocrine tumors (GEPNET) in a referral center of South India, JIPMER, Puducherry, India.

METHODS

There were 55 gastroenteropancreatic region neuroendocrine neoplasms (NEN) assessed for demographic, clinical and radiological features. Gross morphological features, histopathological features, mitotic index, Ki67 proliferation index, and immunohistochemical positivity for synaptophysin, chromogranin-A, CD-56, NSE (Neuron Specific Enolase) and pan-cytokeratin (Pan-CK) were also assessed.

RESULTS

The majority were nonfunctional tumors presenting with abdominal pain, gastrointestinal bleed, vomiting, jaundice, and loss of weight and appetite. The sites of involvement according to the order of frequency were duodenum, stomach, rectum, pancreas, ileum, appendix and jejunum. The endoscopic appearance of duodenal and jejunal tumors showed polypoidal, nodular and ulceroproliferative growth. These tumors were diagnosed by preoperative biopsy; 54% of them were grade-1 neuroendocrine tumors exhibiting nesting, trabecular, cord, and solid sheet patterns. All 55 cases were synaptophysin-positive with variable positivity for chromogranin, neuron-specific enolase, CD56, and Pan-CK. Mixed adenoneuroendocrine carcinomas (MANECs) involving the duodenum and stomach comprised 7.3% of all GEPNETs. Pancreatic neuroendocrine tumors constituted 9% of all tumors; one was multifocal. Lymph node metastasis was seen in 12/55 tumors; 6/12 showed liver metastasis also. All metastasizing tumors measured less than 4 cm in size. Statistical correlation of the tumor grade, mitotic count and Ki67 index as analysed by Spearman's correlation between the paired data denoted by r^s in 55 tumors showed a strong correlation between mitotic count and Ki67 index; a moderate correlation was noted between the tumor grade and Ki67 index.

CONCLUSION

The clinicopathologic profile of 55 GEPNET revealed a majority to be sporadic Grade 1 tumor. Tumors that showed lymph node and liver metastasis were less than 4 cm in size. MANECs were found in the duodenum and stomach.

Mixed adenoneuroendocrine carcinoma of the hepatic bile duct: a case report and review of the literature

Background

The World Health Organization's updated classification of digestive system neuroendocrine tumors in 2010 first proposed the classification of mixed adenoneuroendocrine carcinoma (MANEC). The incidence of biliary malignant tumors with neuroendocrine tumors accounts for less than 1% of all neuroendocrine tumors. Moreover, the incidence of hilar bile duct with MANEC is very rare.

Case presentation

A 65-year-old female patient came to our hospital for repeated abdominal pain for more than 4 months and skin sclera yellow staining for 1 week. Contrast-enhanced computed tomography imaging and magnetic resonance results suggested a hilar tumor for Bismuth-Corlette Type II. The patient underwent radical surgery for hilar cholangiocarcinoma. Finally, the patient was diagnosed with hilar bile duct MANEC, staged 1 (pT1N0M0) based on the eighth edition of the AJCC. Histopathology showed that the tumor was a biliary tumor with both adenocarcinoma and neuroendocrine carcinoma. No evidence of recurrence and metastasis after 20 months of follow-up.

Conclusions

We first reported a MANEC that originated in the hilar bile duct. As far as we known, there were few reports of biliary MANEC, and the overall prognosis was poor. We also found that the higher the Ki-67 index, the worse the prognosis of this type of patient. Radical surgery is the most effective treatment.

Clinicopathological Study of 100 Cases of Neuroendocrine Neoplasms of the Gastroenteropancreatic System: A Tertiary Cancer Center Experience

Background: The incidence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) is on the rise. Although the clinicopathologic characteristics of NENs have been previously reviewed in the literature, the data published in the Indian literature so far are sparse. This study aims to review the clinicopathological features of GEP-NENs, diagnosed at our institution, and that were classified and graded according to the World Health Organization 2010 classification system. Materials and Methods: One hundred patients with GEP-NENs presenting to our institute from August 2012 to May 2016 were analyzed retrospectively. Demographic data and tumor characteristics were expressed as number, percentage, and mean value. Tumor grade was correlated to metastasis through the Chi-square test. p < 0.05 was considered statistically significant. Results: Of the 100 cases studied, 58 were male and 42 were female. The most common primary site was the pancreas (n = 36), followed by the small intestine (n = 19), esophagus (n = 17), stomach (n = 15), colon (n = 6), rectum (n = 4), and appendix (n = 3). The incidence of neuroendocrine tumor (NET) Grade 1 (NET G1) was higher (n = 40) compared to NET Grade 2 (NET G2) (n = 25) and neuroendocrine carcinoma Grade 3 (NEC G3) (n = 35). Overall in these 100 cases, NET G1 tumors and NET G2 tumors were most common in the pancreas (n = 18/36) and (n = 13/36), respectively. NEC G3 tumors were most common in the esophagus (n = 16/17). The most common site of distant metastasis was the liver (n = 23/26). Conclusion: We elucidated the epidemiological and clinicopathological features of patients presenting to our institute with GEP-NENs.

Different somatostatin and CXCR4 chemokine receptor expression in gastroenteropancreatic neuroendocrine neoplasms depending on their origin

Somatostatin receptors (SST), especially SST2A, are known for their overexpression in well-differentiated gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN). The chemokine receptor CXCR4, in contrast, is considered to be present mainly in highly proliferative and advanced tumors. However, comprehensive data are still lacking on potential differences in SST or CXCR4 expression pattern in GEP-NEN in dependence on the place of origin. Overall, 412 samples from 165 GEP-NEN patients, comprising both primary tumors (PT) and metastases (MTS), originating from different parts of the gastrointestinal tract or the pancreas were evaluated for SST and CXCR4 expression by means of immunohistochemistry using monoclonal antibodies. SST2A was present in 85% of PT with a high intensity of expression, followed by SST5 (23%), CXCR4 (21%), SST3 (10%), SST1 (9%), and SST4 (4%). PT displayed higher SST2A and chromogranin A (CgA) expression levels than MTS. In both PT and MTS lower SST2A and CgA expression levels were found in tumors originating from the appendix or colon, compared to tumors from other origins. Tumors derived from appendix or colon were associated with significantly worse patient outcomes. Positive correlations were noted between SST2A and CgA as well as between CXCR4 and Ki-67 expression levels. SST2A and CgA negativity of the tumors was significantly associated with poor patient outcomes. All in all, SST2A was the most prominent receptor expressed in the GEP-NEN samples investigated. However, expression levels varied considerably depending on the location of the primary tumor.

Combination of laparoscopy and endoscopy as an option for treatment patients with gastric neuroendocrine tumors

Background

Neuroendocrine tumors (NETs) are relatively rare neoplasms with the increasing survival due to the development of early diagnostics. There is no universal position in treatment and follow up of small (~20 mm) gastric NETs.

Clinical cases

Two female patients 51 and 66 y.o. with multiple gastric NETs <2 cm were observed in our department. In both cases treatment was performed by combination of two minimally invasive technologies: laparoscopy and gastroscopy. According to the localization of tumors in one case intraluminal gastric resection controlled by laparoscopy was performed. In the second case laparoscopic gastric resection with gastroscopy assistance was done.

Discussion

There are two positions for surgical treatment of small NETs: to operate as the typical premalignant neoplasm or to make submucosa resections. We demonstrated combination of laparoscopy and gastroscopy as feasible approach with minimal risk of complications.

Neuroendocrine Carcinoma of Duodenum-an Uncommon Tumour at an Unusual Site

Neuroendocrine carcinoma rarely occurs in the duodenum, and most cases of neuroendocrine carcinoma in the duodenum show rapid progression of the disease. Such cases have poor prognosis even with radical surgery with or without chemotherapy with low 5-year survival rate. We present a case of a 52-year-old man who presented with abdominal pain of 1-month duration and one episode of vomiting. Upper gastrointestinal endoscopy revealed polypoidal lesions in the first and second part of the duodenum. Whipple's procedure was performed. Diagnosis of poorly differentiated neuroendocrine carcinoma was made with extension to pancreas with peripancreatic lymph node metastases. The patient expired on post operative day 17 following cardiac arrest.

Extremely Long Survival under Combined Immunotherapy in a Metastatic Functional Neuroendocrine Neoplasia Patient

Treatment and prognosis of neuroendocrine neoplasia depends on tumor size, stage, grade, resectability, and extent of distant metastasis. In most cases a multimodality approach including surgical, locally invasive procedures, peptide-guided radioreceptor therapy (PRRT), and medical therapies represent the mainstay of treatment in advanced disease. In the reported case, a 68-year-old man was diagnosed in 2010 with an initially functional (histamine) neuroendocrine tumor of gastric type III, G2, stage IVB, cT4cN1cM1 (hepatic, peritoneal, nodal, osseous), including a hepatic tumor load of 25%. Intensive multimodality approaches including combined immunotherapy (vaccination and PD-1/CTLA-4 blockade) led to a survival of 8 years until now with a high quality of life and minimal residual disease (only a single, small paragastric recurrence) despite the dedifferentiation of the tumor into a neuroendocrine carcinoma G3 (Ki-67 of 80%) including a nonfunctional stage.