Endocrine tumors of the gastrointestinal tract and pancreas: grading, tumor size and proliferation index do not predict malignant behavior

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.

Clinicopathologic analysis of primary gastroenteropancreatic poorly differentiated neuroendocrine carcinoma; A ten year retrospective study of 68 cases at Moffit Cancer Center

Objective:

To assess clinicopathological characteristics of primary gastro-entero-pancreatic poorly differentiated neuroendocrine carcinomas (GEP-PDNECAs) and evaluate overall survival in patients treated with systemic platinum and etoposide therapy.

Methods:

A detailed retrospective review of clinico-pathologic data (1999-2009) on 68 consecutive adult patients with primary GEP-PDNECAs was carried out, from H Lee Moffit Cancer Center and Research Institute, Tampa, Florida; USA, based on electronic patient records, specialty consultation files, tumor registry, social security index and pathology archives. All available tumor slides were reviewed and subtyped by neuro-endocrine pathologists. Clinicopathologic data and patient survival were analyzed.

Results:

Of 68 patients 41 were males and 27 females with a mean age of 42 years (range: 25-76 years). Regarding the site of origin, 39 patients were of the colorectal location, 19 from the pancreas, 04 from small intestines, 03 from stomach and 03 were multi-focal from colon, small intestine and pancreas. Sixty three of 68 (93%) patients presented with lymph node/distant metastases. Of 68 tumors 37 (54%) were classified as small cell carcinoma (SCCA), 16 (24%) large cell carcinoma (LCCA), 5 (7%) mixed small and large cell (MSLCCA) and 10 (15%) poorly differentiated carcinoma with neuroendocrine features (PDCA-NEF). Neuroendocrine differentiation was confirmed by positivity for chromogranin in 38/65 (55%), synaptophysin in 62/67 (92%) and CD56 in 17/21 (81%) cases. One neuroendocrine marker was positive in 22/68 (32%), 2 in 40/68 (59%) and all 3 were positive in 9/68 (13%) cases. Fifty-eight of 68 (85%) patients were treated with platinum and etoposide. Overall patient survival at 1, 3 5 and 10 years was 85%, 40%, 16% and 1.5% respectively. Patient survival was independent of age (r= 0.1022), sex (r= -0.909) and histologic tumor subtype (r=0.1028) (p= 0.128) but was related to distant metastases (r=0.306; p=0.0383).

Conclusions:

GEP-PDNECA occurred in many part of the GI tract, most commonly in the colorectal region. Positivity of neuroendocrine markers was variable, which helped to confirm neuro-endocrine differentiation and to avoid under-diagnosis of GEP-PDNECA, especially in metastatic setting. Overall prognosis of GEP-PDNECA patients following platinum and etoposide therapy in our series was relatively favorable but remained poor in the presence of distant metastases.

Comparison of the prognostic values of the 2010 WHO classification, AJCC 7th edition, and ENETS classification of gastric neuroendocrine tumors

The ability of the European Neuroendocrine Tumor Society (ENETS) system, 2010 World Health Organization (WHO) grading system, and American Joint Committee on Cancer (AJCC) staging system to predict survival after gastric neuroendocrine tumor (NET) resection has not yet been validated.We retrospectively evaluated 175 gastric NETs from 1996 to 2014. WHO grade 3 (G3) patients (n = 66) had a lower survival rate than grade 1 (G1) (n = 39) or grade 2 (G2) (n = 13) patients, with similar high survival rates for G1 and G2 patients. G3 patients had a lower survival rate than mixed-type patients (n = 57). Using the AJCC classification, most of the G1/2 NETs (86.6%) were confined to T1/T2, N0 tumor, and stage I/IIa, but the survival rate was not well distributed. In contrast, G3/mixed tumors were well distributed in terms of T, N, stage, and survival. Using the ENETS classification, 64.6% of the tumors were T2 and only 8.6% were T3. In addition, 49.7% were stage IIIb and only 1.9% was IIa, with poor survival distribution.Our findings strongly suggested that the WHO and ENETS classification systems have shown a low prognostic value. The AJCC TNM system showed a low prognostic value for well-differentiated NETs (G1 or G2). In contrast, the AJCC TNM system had a high prognostic value for G3 or mixed tumors.

Comparison of World Health Organization 2000/2004 and World Health Organization 2010 classifications for gastrointestinal and pancreatic neuroendocrine tumors

Gastroenteropancreatic neuroendocrine tumors (GEPNETs) were divided into 4 groups based on tumor diameter and stage in World Health Organization (WHO) 2000/2004 classification as well-differentiated endocrine tumor benign (WDETB), well-differentiated endocrine tumor with uncertain behavior (WDETUB), well-differentiated endocrine carcinoma (WDEC), and poorly differentiated endocrine carcinoma (PDEC). World Health Organization 2000/2004 was not widely accepted because of stage-related classification and the category of "uncertain behavior." The European NET Society proposed a grading classification and site-specific staging system in 2010. Gastroenteropancreatic NETs were divided into 3 groups as NET grade 1 (G1), NET grade 2 (G2), and neuroendocrine carcinoma (NEC) grade 3 (G3) based on mitoses and the Ki-67 index. We evaluated 63 GEPNET cases according to both classifications. We compared two classifications and the tumor groups in terms of prognostic parameters (diameter, mitosis, Ki-67 index, angioinvasion, perineural invasion, necrosis, and metastasis) and pathologic stage. All 14 cases diagnosed as PDEC were included in the NEC G3 according to WHO 2010. Seventeen cases were diagnosed as WDETB, 9 as WDETUB, and 23 as WDEC. There was statistically significant difference between these groups in terms of all prognostic parameters except for necrosis, mitosis, Ki-67 index, and grade. All WDETB cases, 89% of WDETUBs, and 87% of WDECs were included in the NET G1. There were 45 cases evaluated as NET G1 and 4 cases as NET G2 according to WHO 2010. Metastasis and perineural invasion were more common in NET G2, no significant differences in other parameters. In conclusion, WHO 2010 is easier to use, whereas WHO 2000/2004 shows higher correlation with prognosis. However, it includes benign and uncertain behavior categories, although small tumors with low proliferative activity can also cause metastases. All GEPNETs should be considered potentially malignant.

The relationship between lymphatic vascular density and vascular endothelial growth factor A (VEGF-A) expression with clinical-pathological features and survival in pancreatic adenocarcinomas

BACKGROUND

Pancreatic cancer is a rare tumor with an extremely low survival rate. Its known risk factors include the chronic use of tobacco and excessive alcohol consumption and the presence of chronic inflammatory diseases, such as pancreatitis and type 2 diabetes. Angiogenesis and lymphangiogenesis, which have been the focus of recent research, are considered prognostic factors for cancer development. Knowing the angiogenic and lymphangiogenic profiles of a tumor may provide new insights for designing treatments according to the different properties of the tumor. The aim of this study was to evaluate the density of blood and lymphatic vessels, and the expression of VEGF-A, in pancreatic adenocarcinomas, as well as the relationship between blood and lymphatic vascular density and the prognostically important clinical-pathological features of pancreatic tumors.

METHODS

Paraffin blocks containing tumor samples from 100 patients who were diagnosed with pancreatic cancer between 1990 and 2010 were used to construct a tissue microarray. VEGF expression was assessed in these samples by immunohistochemistry. To assess the lymphatic and vascular properties of the tumors, 63 cases that contained sufficient material were sectioned routinely. The sections were then stained with the D2-40 antibody to identify the lymphatic vessels and with a CD34 antibody to identify the blood vessels. The vessels were counted individually with the Leica Application Suite v4 program. All statistical analyses were performed using SPSS 18.0 (Chicago, IL, USA) software, and p values ≤ 0.05 were considered significant.

RESULTS

In the Cox regression analysis, advanced age (p=0.03) and a history of type 2 diabetes (p=0.014) or chronic pancreatitis (p=0.02) were shown to be prognostic factors for pancreatic cancer. Blood vessel density (BVD) had no relationship with clinical-pathological features or death. Lymphatic vessel density (LVD) was inversely correlated with death (p=0.002), and by Kaplan-Meyer survival analysis, we found a significant association between low LVD (p=0.021), VEGF expression (p=0.023) and low patient survival.

CONCLUSIONS

Pancreatic carcinogenesis is related to a history of chronic inflammatory processes, such as type 2 diabetes and chronic pancreatitis. In pancreatic cancer development, lymphangiogenesis can be considered an early event that enables the dissemination of metastases. VEGF expression and low LVD can be considered as poor prognostic factors as tumors with this profile are fast growing and highly aggressive.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5113892881028514.

Changes in miR-143 and miR-21 expression and clinicopathological correlations in pancreatic cancers

OBJECTIVES

Despite advances in clinical management of pancreatic cancer (PC), there is still room for improvement in early detection, diagnosis, and treatment strategies. The role of microRNAs (miRNAs) in tumor biology might pinpoint an alteration in expression of miRNAs as new diagnostic/prognostic biomarkers.

METHODS

Expression levels of miR-143 and miR-21 and correlations with clinicopathological features were analyzed in 26 matched pairs of tumor and adjacent noncancerous tissue samples collected from patients with PCs, including 18 pancreatic ductal adenocarcinomas (PDACs) and 8 adenocarcinomas of Vater's papilla (PVACs).

RESULTS

Compared to normal tissues, miR-143 was up-regulated in both PDAC and PVAC tumor samples (P = 0.0028 and P = 0.039, respectively). Conversely, alterations in miR-21 expression were significantly different in PDAC versus PVAC samples (P = 0.0049). Tumor levels of miR-21 were associated with preoperative serum levels of CA 19-9 (r = 0.63, P = 0.0022), whereas miR-143 expression was negatively correlated to lymph node spreading (r = -0.64; P = 0.0004). Correlation between miR-143 and miR-21 expression levels in patients with PDAC was observed (r = 0.53, P = 0.023).

CONCLUSIONS

Deregulation of miR-143 and miR-21 may reflect histological features and biological behavior of different PCs. Association data with clinical parameters might indicate a prognostic significance for miR-143 and miR-21 in PCs.

Gastric GIST with synchronous neuroendocrine tumour of the pancreas in a patient without neurofibromatosis type 1

The gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the gastrointestinal tract. These are rare tumours with an incidence of 15 new cases per million per year. The occurrence of neuroendocrine tumours of the pancreas is rare, representing 1-5% of pancreatic cancers, and it is estimated that its incidence does not exceed five to one million. GISTs are common in patients with neurofibromatosis type 1 (NF1); there are few reported cases of synchronous neuroendocrine tumours in these patients and most are pheochromocytomas. The case reports a 64-year-old woman referred to the General Surgery Outpatient for incidental finding of gastric and pancreatic tumours. She underwent a radical subtotal pancreatectomy + partial gastrectomy with jejunal transposition. The pathological examination revealed: gastric GISTs and a well-differentiated neuroendocrine carcinoma of the pancreas. This is the second case published so far of a patient with both tumours and without NF1. Posterior studies must be performed to evaluate if some other genetic disorder is involved in these patients without NF1.

Neuroendocrine tumor of the pancreas in a patient with tuberous sclerosis: a case report and review of the literature

A rare case of pancreatic neuroendocrine neoplasm in a patient with tuberous sclerosis complex is described. The patient was a 31-year-old man who had multiple congenital subependymal nodules, bilateral cortical tubers, and seizures of difficult control. A 2.3 cm × 2 cm well-delimitated solid tumor in the tail of the pancreas was discovered during a monitoring abdominal computed tomography. A distal pancreatectomy was performed. Histologically, the tumor was formed by uniform cells with moderated cytoplasm arranged in a combined trabecular and nested pattern. The nuclear features were bland, and mitosis was infrequent. There was no vascular invasion. Immunoreactivity for cytokeratine AE1/AE3, chromogranin A, and synaptophysin confirmed the neuroendocrine nature of this neoplasia. Pancreatic hormones were negatives. One of the 5 lymph nodes isolated from the peripancreatic adipose tissue was positive for metastases. Small series and case reports have documented that in tuberous sclerosis many endocrine system alterations might occur, affecting the function of the pituitary, parathyroid, and other neuroendocrine tissue, including islet cells of the pancreas. However, the true association of these pathological conditions remains uncertain. As far as we know, there are 10 cases reported of pancreatic neuroendocrine tumors in a setting of tuberous sclerosis complex, in which 2 cases resulted in malignant, nonfunctioning pancreatic neuroendocrine tumors.

RUNX1T1: a novel predictor of liver metastasis in primary pancreatic endocrine neoplasms

OBJECTIVES

Using gene expression profiling on frozen primary pancreatic endocrine tumors (PETs), we discovered RUNX1T1 as a leading candidate progression gene. This study was designed (1) to validate the differential expression of RUNX1T1 protein on independent test sets of metastatic and nonmetastatic PETs and (2) to determine if RUNX1T1 underexpression in primary tumors was predictive of liver metastases.

METHODS

Immunohistochemical expression of RUNX1T1 protein was quantified using Allred scores on archival metastatic (n = 13) and nonmetastatic (n = 24) primary adult PET tissues using custom-designed tissue microarrays. Wilcoxon rank sum/Fisher exact tests and receiver operating characteristic curves were used in the data analysis.

RESULTS

Median RUNX1T1 scores were 2 (2-7) and 6 (3-8) in metastatic versus nonmetastatic primaries (P < 0.0001). Eleven of 13 metastatic and 1 of 24 nonmetastatic primaries exhibited RUNX1T1-scores of 4 or less (P < 0.0001). Low RUNX1T1 expression was highly associated with hepatic metastases (P < 0.0001), whereas conventional histological criteria (Ki-67 index, mitotic rate, necrosis) were weakly associated with metastases (P = 0.08-0.15). Considering RUNX1T1 expression (Allred) score of 4 or less to be predictive, the sensitivity to predict hepatic metastases was 85%, with a specificity of 96%.

CONCLUSIONS

RUNX1T1 protein is underexpressed in well-differentiated metastatic primary PETs relative to nonmetastatic primaries and emerges as a promising novel biomarker for prediction of liver metastases.

Proliferative rate in endoscopic ultrasound fine-needle aspiration of pancreatic endocrine tumors: correlation with clinical behavior

BACKGROUND

The objectives of this study were to evaluate the role of endoscopic ultrasonography (EUS)-guided fine-needle aspiration (FNA) in the preoperative diagnosis of pancreatic endocrine tumors (PETs) and to investigate whether the Ki-67 index determined on cytologic material could help predict their behavior.

METHODS

The study included 10 men and 5 women (ratio of men to women, 2:1) with a mean age of 62.4 years (range, 40-79 years). Diff-Quik- and Papanicolaou-stained FNA samples were analyzed retrospectively, and immunocytochemical stains were performed for chromogranin A, synaptophysin, vimentin, alpha-1-antitrypsin, and Ki-67 on cell block sections. The Ki-67 index was evaluated by using digital image-analysis software and was correlated with follow-up (mean, 21.5 months; range, 2-43 months).

RESULTS

The overall survival was rate 86.7% (13 of 15 patients). Seven of 15 patients (46.7%) patients developed lymph node and/or hematogenous metastases. The Ki-67 index in PETs with no metastases was lower (mean, 6.3%; range, 2%-13%) than in clinically aggressive (metastatic) tumors (mean, 7.7%; range, 3%-27%; P = .03). None of the tumors that had a Ki-67 index < or =2% were metastatic. Both patients who died of disease had a Ki-67 index of 4%.

CONCLUSIONS

Although tumors with metastatic potential tended to exhibit a slightly higher Ki-67 index, there was a significant overlap with nonmetastatic tumors, and PETs that had a very low proliferative rate still could behave aggressively; therefore, the authors concluded that the Ki-67 index does not predict the risk of disease progression in patients with PETs.

Predicting prognosis in gastroentero-pancreatic neuroendocrine tumors: an overview and the value of Ki-67 immunostaining

Gastroenteropancreatic neuroendocrine tumors (GEP-NETS) are unusual and rare neoplasms for which prognostic assessment and the diagnosis of malignancy, on the basis of histology alone, represent considerable challenges for the pathologist. To date, many molecular markers have been identified with a view to providing accurate and timely prediction of response to treatment and long-term survival. Proliferation remains a key feature of tumor progression, which has been widely estimated by the immunohistochemical use of the Ki-67 nuclear antigen. Given the continued difficulties inherent in prediction of malignancy in pancreatic neuroendocrine tumors (PETs) in particular, it has become unclear whether Ki-67 is truly a reliable prognostication marker. This review seeks to better establish what the consensus is on the role of the Ki-67 proliferation index as a prognostic indicator of long-term outcome in pancreatic neuroendocrine tumors. We conclude that most studies favor the utility of the Ki-67 proliferation index despite different critical percentages and in concert with other pathological parameters in the routine work-up of PETs.

Composite signet-ring cell/neuroendocrine carcinoma of the stomach with a metastatic neuroendocrine carcinoma component: a better prognosis entity

Background

Mixed (composite) exocrine-neuroendocrine cell carcinomas are defined as an intimate admixture of neoplastic glandular exocrine and neuroendocrine cell types. Although gastric adenocarcinoma containing a small number of neuroendocrine cells is a relatively frequent occurrence, gastric neoplasms containing equal proportions of both cell types are rare.

Case Presentation

We present a case of composite exocrine (signet-ring cell)-neuroendocrine cell carcinoma, in which the neoplastic signet-ring cell exocrine and neuroendocrine constituents occurred in fairly equivalent amounts, whereas only the neuroendocrine carcinoma portion of the tumor represented the metastatic component. Light microscopy, immunohistochemical and electron microscopic findings are described, and the literature is reviewed.

Conclusion

This study confirms the ability of pluripotent precursor cells to differentiate into either adenocarcinoma or neuroendocrine tumor and, justifying the designation of composite exocrine-neuroendocrine cell carcinoma as the appropriate classification for this tumor. The protracted clinical course further supports the notion that composite signet-ring cell/neuroendocrine carcinoma tumors behave relatively less aggressively than the pure forms of the former cell type.