Gallbladder Mixed Neuroendocrine-Non-neuroendocrine Neoplasm (MiNEN) Arising in Intracholecystic Papillary Neoplasm: Clinicopathologic and Molecular Analysis of a Case and Review of the Literature

Methylation-Based Characterization of a New IDH2 Mutation in Sinonasal Undifferentiated Carcinoma

Mutations affecting codon 172 of the isocitrate dehydrogenase 2 (IDH2) gene define a subgroup of sinonasal undifferentiated carcinomas (SNUCs) with a relatively favorable prognosis and a globally hypermethylated phenotype. They are also recurrent (along with IDH1 mutations) in gliomas, acute myeloid leukemia, and intrahepatic cholangiocarcinoma. Commonly reported mutations, all associated with aberrant IDH2 enzymatic activity, include R172K, R172S, R172T, R172G, and R172M. We present a case of SNUC with a never-before-described IDH2 mutation, R172A. Our report compares the methylation pattern of our sample to other cases from the Gene Expression Omnibus database. Hierarchical clustering suggests a strong association between our sample and other IDH-mutant SNUCs and a clear distinction between sinonasal normal tissues and tumors. Principal component analysis (PCA), using 100 principal components explaining 94.5% of the variance, showed the position of our sample to be within 1.02 standard deviation of the other IDH-mutant SNUCs. A molecular modeling analysis of the IDH2 R172A versus other R172 variants provides a structural explanation to how they affect the protein active site. Our findings thus suggest that the R172A mutation in IDH2 confers a gain of function similar to other R172 mutations in IDH2, resulting in a similar hypermethylated profile.

Relation between WHO Classification and Location- and Functionality-Based Classifications of Neuroendocrine Neoplasms of the Digestive Tract

Practice of neuroendocrine neoplasms (NENs) of the digestive tract, which comprise of a highly diverse group of tumors with a rising incidence, faces multiple biological, diagnostic, and therapeutic issues. Part of these issues is due to misuse and misinterpretation of the classification and terminology of NENs of the digestive tract, which make it increasingly challenging to evaluate and compare the literature. For instance, grade 3 neuroendocrine tumors (NETs) are frequently referred to as neuroendocrine carcinomas (NECs) and vice versa, while NECs are, by definition, high grade and therefore constitute a separate entity from NETs. Moreover, the term NET is regularly misused to describe NENs in general, and NETs are frequently referred to as benign, while they should always be considered malignancies as they do have metastatic potential. To prevent misconceptions in future NEN-related research, we reviewed the most recent terminology used to classify NENs of the digestive tract and created an overview that combines the classification of these NENs according to the World Health Organization (WHO) with location- and functionality-based classifications. This overview may help clinicians and researchers in understanding the current literature and could serve as a guide in the clinic as well as for writing future studies on NENs of the digestive tract. In this way, we aim for the universal use of terminology, thereby providing an efficient foundation for future NEN-related research.

Digestive MiNENs: Could histological classification and molecular characterization drive clinical outcome and therapeutic approach?

Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) are epithelial neoplasms in which neuroendocrine and non-neuroendocrine discrete components are combined, each of which constitutes ≥ 30% of the neoplasm. The finding of an additional neuroendocrine component seems to characterize the tumor's biological behavior. Few studies have proved MiNENs histogenetic and molecular characterization, and the development of molecular markers for more accurate classification of MiNENs represents a clinical need. However, a common origin of the neuroendocrine and non-neuroendocrine components from a pluripotent cancer stem cell could be suggested. The optimal clinical management of MiNENS is largely unknown. Whenever feasible, curative-intent resection should be performed for localized disease; in advanced disease, the treatment should be targeted to the component responsible for the metastatic spreading. This paper provides a revision of the current knowledge on MiNENs, focusing on available evidence about their molecular characterization to suggest a prognostic stratification of these rare forms.

Clinical features and outcomes analysis of Gallbladder neuroendocrine carcinoma

Purpose

Gallbladder neuroendocrine carcinoma (GB-NEC) is an uncommon and highly malignant tumor. This research aimed to investigate the clinical characteristics and prognostic factors of GB-NEC.

Materials and Methods

Our survey of case reports from January 2000 to May 2022 screened a total of 84 patients with complete data who received surgical resection for gallbladder NEC. Log-rank generated survival curves using the Kaplan-Meier method for univariate survival analysis. To identify GB-NEC independent prognostic indicators for overall survival (OS), univariate and multivariate Cox proportional hazard analyses were conducted.

Results

These patients consisted of 25 men and 59 women, with an average age of 60 (range 29-85). Patients under 60 years old made up 44% of the population, while patients over 60 made up 56%. Fifty-three tumors were advanced pathologic TNM stage III and IV. After surgery, 44 patients underwent chemotherapy or radiotherapy. The median OS of 84 patients with GB-NEC was 16.8 months. In univariate and multivariate analysis, tumor size (diameter ≥5 cm), TNM tumor stage, and the receipt of postoperative adjuvant chemotherapy are independent factors influencing the prognosis of patients with GB-NEC.

Conclusion

Tumor size (diameter ≥5 cm) and TNM tumor stage were independently related to a shorter OS. An enhanced OS was independently linked to receiving postoperative adjuvant chemotherapy.

Extensively Invasive Gallbladder Cancer from Intracholecystic Papillary Neoplasm Treated with Pylorus-Preserving Pancreaticoduodenectomy and Extended Cholecystectomy: A Case Report and Literature Review

Background

Intracholecystic papillary neoplasm (ICPN) is a rare tumor first classified by the World Health Organization in 2010. ICPN is a counterpart of the intraductal papillary mucinous neoplasm of the pancreas and intraductal papillary neoplasm of the bile duct. Previous reports on ICPN are limited; thus, the diagnosis, surgical intervention, and prognosis are controversial. Here, we report an extensively invasive gallbladder cancer arising in ICPN treated with pylorus-preserving pancreaticoduodenectomy (PPPD) and extended cholecystectomy. Case Presentation. A 75-year-old man presented to another hospital with jaundice for 1 month. Laboratory findings showed elevated total bilirubin, 10.6 mg/dL and carbohydrate antigen 19-9, 54.8 U/mL. Computed tomography showed a well-enhanced tumor located in the distal bile duct and dilated hepatic bile duct. The gallbladder wall was thickened and homogeneously enhanced. Endoscopic retrograde cholangiopancreatography revealed a filling defect in the distal common bile duct, and intraductal ultrasonography showed a papillary tumor in the common bile duct, indicating tumor invasion of the bile duct subserosa. Subsequent bile duct brush cytology revealed adenocarcinoma. The patient was referred to our hospital for surgical treatment and underwent an open PPPD. Intraoperative findings showed a thickened and indurated gallbladder wall, suggesting concurrent gallbladder cancer; thus, the patient subsequently underwent PPPD and extended cholecystectomy. Histopathological findings confirmed gallbladder carcinoma originating from ICPN, which extensively invaded the liver, common bile duct, and pancreas. The patient started adjuvant chemotherapy (tegafur/gimeracil/oteracil) 1 month after surgery and had no recurrence at follow-up after 1 year.

Conclusions

Accurate preoperative diagnosis of ICPN, including the extent of tumor invasion is challenging. To ensure complete curability, the development of an optimal surgical strategy considering preoperative examinations and intraoperative findings is essential.

The Clinical and Pathologic Features of Intracholecystic Papillary-Tubular Neoplasms of the Gallbladder

Intracholecystic papillary-tubular neoplasm denotes a discrete mucosal-based neoplastic proliferation into the gallbladder lumen. It is diagnosed incidentally during cholecystectomy or radiologically during a workup for abdominal pain. The majority of polypoid lesions in the gallbladder are non-neoplastic; therefore, pathologic examination is the gold standard to establish this diagnosis. Intracholecystic papillary-tubular neoplasm is considered as premalignant, although associated invasive carcinomas may be present in the specimen. Invasive carcinoma arising from intracholecystic papillary-tubular neoplasm have a better prognosis than de novo gallbladder carcinomas. The pathology of intracholecystic papillary-tubular neoplasm, including the challenges involved in the diagnosis of this entity, is discussed.

Intra-ampullary papillary-tubular neoplasm combined with ampullary neuroendocrine carcinoma: A case report

BACKGROUND

The ampulla of Vater is an anatomically and histologically complex region giving rise to a heterogenous group of tumors. This is, to the best of our knowledge, the first case of intra-ampullary papillary-tubular neoplasm combined with ampullary neuroendocrine carcinoma reported in the literature.

CASE SUMMARY

A 61-year-old woman presented to the emergency department for evaluation of painless jaundice. Contrast-enhanced computed tomography (CT) of the abdomen and chest showed a periampullary tumor mass measuring 15 mm × 12 mm × 14 mm, with no evidence of locoregional and distant metastases, for which she underwent pancreatoduodenectomy. Histopathologic examination of a resected specimen revealed an intra-ampullary papillary tubular neoplasm with high-grade dysplasia in combination with poorly differentiated grade 3 neuroendocrine carcinoma with a mitotic count of more than 20 mitoses per 10 high power fields and Ki-67 index of 100%. No positive lymph nodes were identified. Her postoperative course was uneventful. Postoperatively, she remained under close surveillance. Multiple liver metastases were observed on follow-up CT 8 mo after the surgery, so systemic therapy with cisplatin and etoposide was initiated.

CONCLUSION

The simultaneous occurrence of neuroendocrine and non-neuroendocrine tumors in the ampulla of Vater is rare and the pathogenesis of such tumors is largely unknown. Due to unpredictable clinical behavior and lack of solid evidence on optimal treatment strategy, close patient surveillance is advised after radical resection of the primary tumor.

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.

Comprehensive Clinical Analysis of Gallbladder Neuroendocrine Neoplasms: A Large-Volume Multicenter Study During One Decade

BACKGROUND

This study aimed to comprehensively investigate the clinicopathologic characteristics and therapeutic situations of gallbladder neuroendocrine neoplasms (GB-NENs) in the real world via a multicenter, large-scale cohort study.

METHODS

The study searched for patients in 143 hospitals in China and enrolled 154 patients with GB-NENs diagnosed in 40 hospitals between 2004 and 2021. Clinicopathologic characteristics and therapeutic approaches were analyzed retrospectively.

RESULTS

The median age at the initial diagnosis of the patients with GB-NENs was 63 years (range 33-83 years), and 61.7% of the patients were women. Tumor-node-metastasis staging classified 92 patients as stage 3 or above. Based on the 2019 World Health Organization classification, 96 cases (62.3%) were confirmed pathologically as poorly differentiated neuroendocrine carcinomas, 13 cases (8.4%) as well-differentiated neuroendocrine tumors, and 45 cases as mixed neuroendocrine-non-neuroendocrine neoplasms. The liver was the most frequent metastatic site. Immunohistochemistry showed that synaptophysin was most frequently positive (80.4%), followed by chromogranin A (61.7%), and CD56 (58.4%). Computed tomography and magnetic resonance imaging showed more common clear boundaries (25/39 cases) and invasive growth features (27 cases). None of these cases had an accurate diagnosis before surgery, with a misdiagnosis rate of 100%. Surgical resection is the main treatment, and platinum-based chemotherapeutic regimens were preferred as adjuvant therapies for patients with GB-NENs. The available survival data for 74 patients showed an overall survival rate of 59% at 1 year, 33% at 3 years, and 29% at 5 years. No significant difference was found between the patients treated with and those treated without adjuvant chemotherapy.

CONCLUSIONS

Gallbladder neuroendocrine neoplasms have high malignancy and a poor prognosis. Importantly, this large-scale cohort study significantly improves our understanding of GB-NENs and will benefit the exploration of its mechanism and treatment modes. Further investigation is necessary to explore the management of this disease.

Mixed neuroendocrine-non-neuroendocrine neoplasm of the gallbladder: case report and literature review

Background

Mixed neuroendocrine–non-neuroendocrine neoplasms (MiNENs) of the gallbladder are rare malignancies. Here we presented two cases and reviewed the related literature.

Case presentation

Our two patients were postoperatively diagnosed with gallbladder MiNENs, which pathologically consisted of a large cell neuroendocrine carcinoma and papillary adenocarcinoma. After cholecystectomy, one patient had a survival time of 30 months, while the other remained alive through 12 months of follow-up. In the literature, a total of 72 cases of gallbladder MiNENs were identified, and with our two patients included, we calculated a male-to-female ratio of 0.22 and a mean age of 64.5 years for the 74 reported cases. About one-half of these patients were found to have gallstones and presented with abdominal pain or discomfort in a relatively early stage. The preoperative diagnosis of these 74 cases mainly relied on abdominal ultrasound, contrast-enhanced computed tomography (CT) scanning, and magnetic resonance imaging or positron emission tomography/CT. However, the final diagnosis was established based upon the pathological evidence and expression of synaptophysin (Syn) and/or chromogranin A identified by immunohistochemical staining or neurosecretory granules detected by electron microscopy. Fifty-eight patients (78.4%) underwent various operations including simple cholecystectomy (n = 14), en bloc cholecystectomy (n = 9), standard or non-standard radical cholecystectomy (n = 25), or extended radical cholecystectomy (n = 6). The mean size of the resected gallbladder masses was 50.8 ± 36.1 mm (n = 63) with regional lymph node metastasis in 37 patients (52.1%), liver invasion or staging greater than T3 in 33 patients (45.8%), and hepatic metastasis in 26 patients (35.1%). The postoperative median survival time was 36 ± 11.42 months (95% confidence interval, 13.62 to 58.38 months). The log-rank analysis did not find that postoperative adjuvant chemotherapy contributed to a longer survival time relative to that among the patients who did not receive chemotherapy (numbers of patients, 15 versus 43; survival times, 36 months versus 30 months, p > 0.05).

Conclusions

Our two cases and the cases in the literature suggest that MiNENs of the gallbladder predominantly occur in women; are associated with early lymph node metastasis, local hepatic invasion, and hepatic metastasis; and can be managed by various surgeries as well as chemotherapy combined with somatostatin analogs.

Pancreatic Neuroendocrine Neoplasms: Updates on Genomic Changes in Inherited Tumour Syndromes and Sporadic Tumours Based on WHO Classification

Pancreatic neuroendocrine neoplasms (PanNENs) are the neuroendocrine neoplasms with greatest rate of increase in incidence. Approximately 10% of PanNENs arise as inherited tumour syndromes which include multiple endocrine neoplasia type 1, multiple endocrine neoplasia type 4, von Hippel-Lindau syndrome, neurofibromatosis type1, tuberous sclerosis complex 1/2, Cowden syndrome, and Glucagon cell hyperplasia and neoplasia as well as familial insulinomatosis. In sporadic PanNENs, driver mutations in MEN1, DAXX/ATRX and mTOR pathway genes are associated with development and progression in pancreatic neuroendocrine tumours. The other changes are in VEGF pathway, Notch pathway, germline mutations in MUTYH, CHEK2, BRCA2, PHLDA3 as well as other genetic alterations. On the other hand, pancreatic neuroendocrine carcinomas share similar genetic alterations with ductal adenocarcinomas, e.g., TP53, RB1 or KRAS. In addition, microRNA and changes in immune microenvironment were noted in PanNENs. Updates on these genetic knowledges contribute to the development of management strategies for patients with PanNENs.

Mixed neuroendocrine-nonneuroendocrine neoplasms of the gastrointestinal system: An update

Mixed neuroendocrine-nonneuroendocrine neoplasms (MiNENs) of the digestive tract are a rare heterogeneous group of tumors that present many challenges in terms of diagnosis and treatment. Over the years, the diagnostic criteria, classification, and clinical behavior of these tumors have been the subjects of ongoing debate, and the various changes in their nomenclature have strengthened the challenges associated with MiNENs. This review is performed to provide an understanding of the key factors involved in the evolution of the designation of these tumors as MiNEN, highlight the current diagnostic criteria, summarize the latest data on pathogenesis and provide information on available treatments. Moreover, this work seeks to increase the awareness about these rare neoplasms by presenting the clinicopathological features and prognostic factors that play important roles in their behavior and discussing their different regions of origin in the gastrointestinal system (GIS). Currently, the MiNEN category also includes tumors in the GIS with a nonneuroendocrine component and epithelial tumors other than adenocarcinoma, depending on the organ of origin. Diagnosis is based on the presence of both morphological components in more than 30% of the tumor. However, this value needs to be reconfirmed with further studies and may be a limiting factor in the diagnosis of MiNEN by biopsy. Furthermore, available clinicopathological data suggest that the inclusion of amphicrine tumors in the definition of MiNEN is not supportive and warrants further investigation. The diagnosis of these tumors is not solely based on immunohistochemical findings. They are not hybrid tumors and both components can act independently; thus, careful grading of each component separately is required. In addition to parameters such as the metastatic state of the tumor at the time of diagnosis and the feasibility of surgical resection, the aggressive potential of both components has paramount importance in the choice of treatment. Regardless of the organ of origin within the GIS, almost MiNENs are tumors with poor prognosis and are frequently encountered in the elderly and men. They are most frequently reported in the colorectum, where data from molecular studies indicate a monoclonal origin; however, further studies are required to provide additional support for this origin.

Mixed neuroendocrine non-neuroendocrine neoplasm of the gallbladder complicated by a pancreaticobiliary maljunction of a non-dilated biliary duct: A case report

RATIONALE

Mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) is a rare tumor. MiNEN of the gallbladder (GB) with pancreaticobiliary maljunction (PMJ) is extremely rare. The origin of MiNEN of the GB remains unknown; the biliary tract normally lacks neuroendocrine cells. MiNEN of the GB has a poor prognosis; because of its rarity, no treatment or management guidelines have been established yet.

PATIENT CONCERNS

A 47-year-old male presenting with right hypochondrial pain and malaise for 3 months was referred to our hospital for further management.

DIAGNOSIS

The neuron-specific enolase level was increased. Contrast-enhanced computed tomography revealed a mass of 70 mm in size with unclear boundaries in the liver. The GB was surrounded by this mass, narrowing the lumen of the GB. Many swollen lymph nodes were observed in the hepatoduodenal ligament. Endoscopic retrograde cholangiopancreatography revealed a PMJ with a non-dilated biliary duct. A percutaneous biopsy was performed on the liver mass, and the pathological findings were neuroendocrine carcinoma (NEC) (small cell type). We diagnosed a NEC of the GB, T3N1M0, stage IIIB (Union for International Cancer Control, 7th edition).

INTERVENTIONS

Because of advanced lymph node metastasis, we considered this tumor difficult to cure solely by surgical intervention. After initial chemotherapy consisting of cisplatin and irinotecan, a marked reduction in both tumor and lymph node sizes enabled conversion surgery. The pathological diagnosis of the resected tumor was MiNEN consisting of NEC and adenocarcinoma. The primary lesion was the adenocarcinoma occupying the luminal side of the GB. As a postsurgical treatment, the patient received additional irradiation therapy to the common hepatic duct and liver stump because of positive surgical margins.

OUTCOMES

At 13 months postoperatively, computed tomography findings revealed the appearance of a hypervascular liver tumor, and laboratory data showed increased serum neuron-specific enolase levels. Chemotherapy was unsuccessful, leading to the death of the patient 36 months from the date of diagnosis.

LESSONS

There are several reports on the development of MiNEN of the GB. In our case, a PMJ-related adenocarcinoma of the GB transdifferentiated into NEC. Further accumulation of cases is necessary to establish a treatment strategy for MiNEN of the GB.

Neuroendocrine carcinoma of the common bile duct associated with congenital bile duct dilatation: a case report

Background

Cholangiocarcinoma is frequently observed in patients with congenital bile duct dilatation (CBDD). Most cholangiocarcinomas are adenocarcinomas. Other types, especially neuroendocrine carcinomas (NECs), are rare. To the best of our knowledge, this is the third reported case of an NEC of the common bile duct associated with CBDD and the first to receive adjuvant chemotherapy for advanced disease.

Case presentation

A 29-year-old woman presented with upper abdominal pain. Preoperative imaging indicated marked dilatation of the common bile duct and a tumor in the middle portion of the common bile duct. She was suspected of having distal cholangiocarcinoma associated with CBDD and underwent pylorus-preserving pancreaticoduodenectomy. Pathological and immunohistological findings led to a final diagnosis of large-cell NEC (pT3aN1M0 pStageIIB). The postoperative course was uneventful, and she was administered cisplatin and irinotecan every 4 weeks (four cycles) as adjuvant chemotherapy. She has remained recurrence-free for 16 months.

Conclusions

NEC might be a differential diagnosis in cases of cholangial tumor associated with congenital bile duct dilatation. This presentation is rare and valuable, and to establish better treatment for NEC, further reports are necessary.

Neuroendocrine Neoplasms of the Gallbladder: A Clinicopathological Analysis of 13 Patients and a Review of the Literature

OBJECTIVES

Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) are rare gallbladder neuroendocrine neoplasms (GB-NENs). This study is aimed at investigating the clinicopathological features of GB-NENs and identifying prognostic factors related to overall survival (OS) of GB-MiNENs.

METHODS

The clinical data and pathological features of 13 patients with GB-NENs in our hospital were retrospectively reviewed. Additionally, 41 GB-MiNENs cases reported in English literature were reviewed and survival analysis was performed.

RESULTS

The mean age of thirteen patients (6 males and 7 females) with GB-NENs was 57.2 years (range: 35-75 years). Two patients were diagnosed with NET grade 1 (G1), two patients with NEC (large cell/small cell = 1/1), and nine patients with MiNENs. Of these 9 patients with MiNENs, 8 had composite tumors and 1 had amphicrine carcinoma. Microscopically, the adenocarcinoma component was located in the surface mucosa, and the neuroendocrine component was in the area of deep invasion, liver infiltration, and lymph node metastasis. Total analysis of 41 GB-MiNENs showed that patients were mainly elderly women (female/male ratio, 2.4 : 1.0; median age, 60 years). Kaplan-Meier's analysis demonstrated that liver metastasis and TNM stage III-IV were associated with decreased OS (P < 0.05), whereas age, sex, tumor size, grade of the neuroendocrine component, lymph node metastasis, and adjuvant chemotherapy were not significantly prognostic indicators of OS. Multivariate analysis identified liver metastasis (hazard ratio = 4.262, 95%confidence interval = 1.066-17.044, P = 0.040) as an independent unfavorable prognostic factor.

CONCLUSIONS

GB-MiNENs were the most common type of GB-NENs in our case series, and neuroendocrine components exhibited more aggressive lymph node metastasis and local invasion than adenocarcinoma. Liver metastasis was a poor prognostic indicator in GB-MiNENs patients.

Rare Mixed Adenoneuroendocrine Carcinoma of the Gallbladder: Case Report and Review of Literature

Patient: Female, 58-year-old

Final Diagnosis: Mixed adenoneuroendocrine carcinoma of the gallbladder

Symptoms: Abdominal pain • asthenia

Medication: —

Clinical Procedure: —

Specialty: Surgery

Unraveling Neuroendocrine Gallbladder Cancer: Comprehensive Clinicopathologic and Molecular Characterization

PURPOSE

Neuroendocrine carcinomas and mixed neuroendocrine non-neuroendocrine neoplasms of the gallbladder (NE GBC) are rare and highly aggressive entities. The cell of origin of NE GBC has been a matter of controversy. Here, we performed a comparative histopathologic and molecular analysis of NE GBC cases and, if present, associated precancerous lesions.

PATIENTS AND METHODS

We selected cases diagnosed between 2000 and 2019 in the Netherlands. Precursors and carcinomas were immunohistochemically compared and analyzed for mutations, gene amplifications, microsatellite instability, and tumor mutational burden using an next-generation sequencing panel containing 523 cancer-related genes. In addition, presence of fusion genes was analyzed using a panel of 55 genes.

RESULTS

Sixty percent of neuroendocrine cases (6/10) presented with a precursor lesion, either intracholecystic papillary neoplasm (n = 3) or biliary intraepithelial neoplasia (n = 3). Immunohistochemically, neuroendocrine components were different from the epithelial precursor lesions. Molecular profiling, however, revealed TP53 mutations shared between different components in five of six cases, indicating a clonal relation. Furthermore, 40% of cases (4/10) harbored at least one potentially actionable alteration. This included (likely) pathogenic mutations in RAD54L, ATM, and BRCA2; amplifications of ERBB2 and MDM2; and a gene fusion involving FGFR3-TACC3. All cases were microsatellite-stable and had a tumor mutational burden of < 10 mutations/Mb.

CONCLUSION

Our data provide insight into the development of NE GBC and suggest a common origin of precancerous epithelial lesions and invasive neuroendocrine components, favoring the hypothesis of lineage transformation. Moreover, nearly half of the NE GBCs carried at least one potentially actionable molecular alteration, highlighting the importance of molecular testing in this highly lethal cancer.

Genomics of High-Grade Neuroendocrine Neoplasms: Well-Differentiated Neuroendocrine Tumor with High-Grade Features (G3 NET) and Neuroendocrine Carcinomas (NEC) of Various Anatomic Sites

High-grade neuroendocrine neoplasms (HG-NENs) are clinically aggressive diseases, the classification of which has recently been redefined. They now include both poorly differentiated NENs (neuroendocrine carcinoma, NECs) and high proliferating well-differentiated NENs (called grade 3 neuroendocrine tumors, G3 NETs, in the digestive system). In the last decade, the "molecular revolution" that has affected all fields of medical oncology has also shed light in the understanding of HG NENs heterogeneity and has provided new diagnostic and therapeutic tools, useful in the management of these malignancies. Considering the kaleidoscopic aspects of HG NENs in various anatomical sites, this review systematically addresses the genomic landscape of such neoplasm throughout the more common thoracic and digestive locations, as well as it will consider other rare but not exceptional primary sites, including the skin, the head and neck, and the urogenital system. The revision of the available literature will then be oriented to understand the translational relevance of molecular data, by analyzing conceptual issues, clinicopathological correlations, and unmet needs in this field.

Neuroendocrine neoplasms of the biliary tree, liver and pancreas: a pathological approach

Neuroendocrine neoplasms of the pancreatobiliary tract and liver are a heterogeneous group that encompass a spectrum of entities with distinct morphological, biological and clinical features. Although in the various anatomical sub-sites of this region they show specific characteristics, these tumors, as a whole, share several etiological and clinical aspects. This review systematically addresses NENs arising in the extrahepatic bile ducts, gallbladder, liver and pancreas, with the principal aim of pinpointing essential diagnostic and classification issues. In addition, the section on hepatic NENs has been expanded to include metastatic disease of unknown primary site.

Mixed Intraepithelial Neoplasia-Well-Differentiated Neuroendocrine Tumor of the Gallbladder: A Hitherto Unreported Combination

Adenocarcinomas and noninvasive intraepithelial neoplasms (either polypoid or flat) are the most common gallbladder tumors; however, neuroendocrine neoplasms (NENs) can also occur. The majority of NENs are represented by neuroendocrine carcinomas (NECs), while neuroendocrine tumors (NETs) are extremely rare in this location. Occasionally, NEN may present as a part of a mixed neoplasm, with a coexisting non-neuroendocrine component. The latest World Health Organization classification denotes these lesions as mixed neuroendocrine-non-NENs (MiNENs). A novel type of MiNEN, the mixed adenoma well-differentiated NET (MANET), has been increasingly recognized and reported. In such lesions, a dysplastic noninvasive neoplasm and a NET represent the exocrine and endocrine component, respectively. MANETs have mostly been identified in the colon, small intestines, and stomach. In this article, we report, we believe, the first case of mixed gallbladder neoplasm with both biliary intraepithelial neoplasia (BilIN) and NET components, which may be regarded as a variant of MANET. Given the expectably favorable prognoses of MANETs, it is imperative not to misdiagnose the infiltrative yet indolent neuroendocrine component as an invasive adenocarcinoma or a NEC.

The clinical profiles, management, and prognostic factors of biliary mixed neuroendocrine nonneuroendocrine neoplasms: A systematic review of the literature

BACKGROUND

Mixed neuroendocrine nonneuroendocrine neoplasms (MiNENs) originating from the biliary system (gallbladder, biliary tract, or ampulla of Vater) are extremely rare and have not been discussed in detail or systematically. We aimed to present the demographics, clinicopathological characteristics, management, and prognostic factors of biliary MiNENs.

METHODS

A systematic search of electronic biomedical databases (Web of Science, PUBMED, and Embase) was performed to identify eligible studies. Survival was analyzed with the Kaplan-Meier method. Log-rank tests were used to evaluate the differences between groups, and the effects of various clinical and histopathological features on prognosis were analyzed by univariate and multivariate Cox regression.

RESULTS

Fifty-three publications (patients, n = 67) were included. The median overall survival time was 21.0 months. Fifty-one patients (76.1%) underwent radical surgery and median survival for 41 months (P < .001). Twenty-two patients who received adjuvant radiochemotherapy treatment after radical surgery had a median survival for 43 months (P = .076). Radical resection (P < .001), Ki-67 index (P = .011), tumor stage (P < .001), neuroendocrine (NEC) grade (P = .011), and non-NEC grade (P = .017) were independent statistically significant prognostic factors according to univariate analysis; radical resection (P = .010) and small morphological subtype (P = .036) were independent statistically significant prognostic factors associated with higher overall survival according to multivariate analysis, and radical resection (P = .005) and age < 65 years (P = .026) were associated with higher recurrence free survival time.

CONCLUSION

Radical resection is essential for long-term survival. Aggressive multimodality therapy with adjuvant radiochemotherapy and biotherapy may improve survival of biliary MiNENs. Further randomized controlled trials are needed to determine the standard treatment.

Mural Intracholecystic Neoplasms Arising in Adenomyomatous Nodules of the Gallbladder: An Analysis of 19 Examples of a Clinicopathologically Distinct Entity

Intracholecystic neoplasms (ICNs) (pyloric gland adenomas and intracholecystic papillary neoplasms, collectively also called intracholecystic papillary/tubular neoplasms) form multifocal, extensive proliferations on the gallbladder mucosa and have a high propensity for invasion (>50%). In this study, 19 examples of a poorly characterized phenomenon, mural papillary mucinous lesions that arise in adenomyomatous nodules and form localized ICNs, were analyzed. Two of these were identified in 1750 consecutive cholecystectomies reviewed specifically for this purpose, placing its incidence at 0.1%. Median age was 68 years. Unlike other gallbladder lesions, these were slightly more common in men (female/male=0.8), and 55% had documented cholelithiasis. All were characterized by a compact multilocular, demarcated, cystic lesion with papillary proliferations and mucinous epithelial lining. The lesions' architecture, distribution, location, and typical size were suggestive of evolution from an underlying adenomyomatous nodule. All had gastric/endocervical-like mucinous epithelium, but 5 also had a focal intestinal-like epithelium. Cytologic atypia was graded as 1 to 3 and defined as 1A: mucinous, without cytoarchitectural atypia (n=3), 1B: mild (n=7), 2: moderate (n=2), and 3: severe atypia (n=7, 3 of which also had invasive carcinoma, 16%). Background gallbladder mucosal involvement was absent in all but 2 cases, both of which had multifocal papillary mucosal nodules. In conclusion, these cases highlight a distinct clinicopathologic entity, that is, mural ICNs arising in adenomyomatous nodules, which, by essentially sparing the "main" mucosa, not displaying "field-effect/defect" phenomenon, and only rarely (16%) showing carcinomatous transformation, are analogous to pancreatic branch duct intraductal papillary mucinous neoplasms.

Looking into digestive mixed neuroendocrine - nonneuroendocrine neoplasms: subtypes, prognosis, and predictive factors

Mixed neuroendocrine - nonneuroendocrine neoplasms (MiNENs) of the digestive system represent a challenge for both pathologists and clinicians. Their nomenclature has changed several times, and their diagnostic criteria, classification and clinical behaviour have been matter of debate over the years. Although several attempts have been made to elucidate the pathogenesis and biology of MiNENs, some issues remain open. This review will provide: a historical background that helps in understanding the evolution of the concept and nomenclature of mixed neoplasms; a revision of the knowledge on this topic, including molecular aspects, to give the reader a comprehensive and practical overview on this challenging field of pathology; a focus on the diagnostic criteria and on the determination of prognostic and predictive factors; and a description of the different tumour types in the different sites of origin.