Microallelotyping defines the monoclonal or the polyclonal origin of mixed and collision endocrine-exocrine tumors of the gut

An Italian real-world multicenter study of patients with advanced mixed neuroendocrine non-neuroendocrine neoplasms (MiNENs) of the gastro-entero-pancreatic system treated with chemotherapy

PURPOSE

The aim of this study is to describe the clinical management of an Italian series of patients with advanced gastro-entero-pancreatic (GEP) MiNENs treated in clinical practice.

METHODS

Clinical records of patients from four Italian referral Centers were retrospectively analyzed to correlate clinical/biological data with clinical outcomes. All the surgical specimens were centrally reviewed.

RESULTS

Clinical data and surgical samples of 51 patients during 1995-2015 were analyzed. Sites of origin were: 32 colorectal, 14 gastro-esophageal, and 5 pancreatobiliary. Twenty-one out of fifty-one (42.2%) developed metachronous distant metastases. Only 5/51 (9.8%) patients received peri-operative therapy, and 23/51 (45.1%) first-line chemotherapy, mostly fluoropyrimidines/oxaliplatin. The NEN component was poorly differentiated in the whole population. Patients with Ki67 index < 55% in the NEC component had a significantly longer median overall survival (OS) (35.3 months; 95% CI 27.1-41.0) than those with Ki67 ≥ 55% (11.9 months; 95% CI 9.1-14.0) P = 0.0005. The median OS was 14 months (95% CI 10.1-19.1) in the whole cohort, with 11.4 months (95% CI 6.2-20.2) in patients who received a first-line therapy.

CONCLUSION

This study confirms that GEP-MiNENs represent a complex disease and that over the past years the clinical management has been predominantly guided by the subjective judgment of the clinicians. Although, in this series, the NEC component appeared mostly responsible for the systemic spread and prognosis on the whole neoplasm, the lack of strong prognostic and predictive factors universally recognized seems to condition their management so far. Future prospective clinical and biomolecular studies could help clinicians to improve clinical management of GEP-MiNENs.

Two Different Tumors and Lung Aspergilloma: An Uncommon Etiopathogenic Association

Several cases reported in the literature have confirmed the link between pulmonary aspergillosis and various malignant diseases. Furthermore, it has been observed that the correlation between carcinoid tumor and lung adenocarcinoma is quite uncommon. The etiopathogenic mechanisms underlying these correlations remain poorly defined. We present the case of a patient with three of these diseases: a lung adenocarcinoma with a lepidic pattern, a typical carcinoid, and pulmonary aspergillosis. An additional noteworthy aspect of this case pertains to the timely detection of both lung malignancies. Thus, the necessity for further investigation to ascertain the pathogenic connection among the three diseases is underscored. The ultimate objective is to enhance the prognosis of individuals diagnosed with lung cancer, which is a prevailing malignant disease on a global scale.

Molecular profiling of gastric neuroendocrine carcinomas

Gastric neuroendocrine carcinoma (G-NEC) usually has NEC and adenocarcinoma components and is considered to have a common origin in gastric adenocarcinoma because common pathogenic mutations are shared. However, G-NEC without adenocarcinoma also exists, and it may have a different mechanism of tumorigenesis. We aimed to elucidate the tumorigenesis of G-NEC by focusing on the proportion of NEC components. Thirteen patients with G-NEC were included in this study. Comprehensive genetic analysis using whole-exome sequencing was performed. G-NEC without an adenocarcinoma component was defined as pure NEC. TP53 was detected as the most frequent gene mutation (85% of the patients), independent of classification. RB1, KMT2C, LTBP1, and RYR2 mutations were identified in two of three pure NEC patients but were not detected in other G-NEC patients. Pure NEC has different somatic mutation profile than other NECs. This study provides insights into the mechanism of tumorigenesis in G-NEC.

Deficient Mismatch Repair Proteins in Gastric Mixed Neuroendocrine Non-Neuroendocrine Neoplasm: A Rare Case Report

Mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) is a rare type of gastric carcinoma with controversial diagnosis and treatment. Recent data implies that deficiency mismatch repair proteins inducing microsatellite instability are considered one of the potential drivers of this disease. Hence, we report a stomach MiNEN with MMR protein loss. An admitted 60-year-old woman complained of epigastric pain. The pathological analysis of the gastro-endoscopic biopsy specimen revealed gastric adenocarcinoma. The radiological staging was cT3N1M0; therefore, she received D2 distal gastrectomy. Suspecting neuroendocrine component admix with adenocarcinoma part on the resected specimen microscopy, applying biomarkers including AE 1/3, synaptophysin, and chromogranin A to confirm the diagnosis of MiNEN. The neuroendocrine part was classified as neuroendocrine tumor grade 2 with Ki 67 at 16.5%. To further understand the molecular characterization of this disease, we evaluated mismatch protein expression by staining MLH1, MSH2, MSH6, and PMS2 antibodies. Interestingly, both components lost MLH1 and PMS2 proteins. Her radical surgery followed oxaliplatin/capecitabine adjuvant chemotherapy. The patient is still well after eight cycles of chemotherapy. dMMR gastric MiNENs and dMMR gastric cancer share many clinical and genetic characteristics. Further studies are necessary to survey the role of dMMR in the prognosis and treatment of this entity.

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.

Long-term surgical outcomes of gastric neuroendocrine carcinoma and mixed neuroendocrine-non-neuroendocrine neoplasms

Background

Neuroendocrine carcinoma (NEC) and mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) are extremely rare subtypes of gastric cancer. MiNEN is a mix of carcinomatous components and neuroendocrine neoplasm in the same lesion. NEC and MiNEN have a poor prognosis, are difficult to diagnose, and have no established treatment. Herein, we assessed the clinicopathological characteristics and long-term surgical outcomes of gastric NEC and MiNEN patients in our hospital.

Methods

We retrospectively assessed 1538 patients pathologically diagnosed with gastric cancer and who underwent curative surgical resection at our institution between January 1999 and October 2021. Of these patients, 25 (1.6%) were pathologically diagnosed with neuroendocrine neoplasms. From these 25 patients, we retrospectively analyzed the clinicopathological characteristics and surgical outcomes of 13 (0.8%) patients pathologically diagnosed with NEC or MiNEN.

Results

The NEC and MiNEN patients consisted of 11 men and 2 women [mean age, 74 (62–84) years]. The preoperative histological diagnoses were NEC (n = 4) and adenocarcinoma (n = 9). The final pathological diagnoses were large cell neuroendocrine carcinoma (LCNEC; n = 7) and MiNEN (n = 6). Total gastrectomy was the most common surgical procedure (9/13, 69.2%), followed by distal gastrectomy (3/13, 23.1%) and proximal gastrectomy (1/13, 7.7%). Immunohistochemical staining showed 8 CD56-positive patients. All 13 patients were positive for chromogranin A and synaptophysin. The mean Ki-67 value was 64.8 (0–95)%, and the mean mitotic score was 107.9 (0–400). Nine patients survived without recurrence postresection. The median postresection overall survival time was 68.7 (8.0–129) months. The 5-year survival rate was 0.75 ([95% CI] 0.408–0.912).

Conclusion

The surgical treatment outcomes of NEC and MiNEN patients were relatively favorable. Although evidence concerning the effectiveness of surgery alone is meager, radical resection as part of multidisciplinary treatment including chemotherapy can potentially improve prognosis.

Mixed neuroendocrine-non-neuroendocrine neoplasms of the digestive system: A mini-review

Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) are rare mixed tumors containing both neuroendocrine (NE) and non-NE components. Each component must occupy at least 30% of the tumor volume by definition. Recent molecular evidence suggests MiNENs are clonal neoplasms and potentially harbor targetable mutations similar to conventional carcinomas. There have been multiple changes in the nomenclature and classification of MiNENs which has created some confusion among pathologists on how to integrate the contributions of each component in a MiNEN, an issue which in turn has resulted in confusion in communication with front-line treating oncologists. This mini review summarizes our current understanding of MiNENs and outline diagnosis, prognosis, and management of these neoplasms. The authors emphasize the importance of treating the most aggressive component of the tumor regardless of its percentage volume.

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.

Coexistence of carcinoid tumor and adenocarcinoma of the lung; morphological, immunohistochemical and genetic analyses, a case report

Background

Pulmonary carcinoid tumors rarely coexist with non-small cell lung carcinoma, and only nine cases have been reported previously. The pathogenesis and origin of these combined tumors remain unclear because of its rarity.

Case presentation

We examined two cases of adenocarcinoma coexisting with a typical or atypical carcinoid tumor: Case 1 was a 77-year-old woman and Case 2 was an 83-year-old woman. Both of these cases had no respiratory symptoms, and underwent pulmonary lobectomies due to incidentally detected lung nodules. Recurrence and metastases were not detected after the surgery. Histologically, carcinoid and adenocarcinoma components were present in both cases. The two components coexisted without mixing with each other. Next-generation sequencing was performed on the two components in these cases. In each case, no common genetic variants were detected.

Conclusion

We considered that our cases could histologically and genetically represent collision tumors that did not share common progenitor cells. Comprehensive analyses such as whole genome sequencing could provide important information for elucidating the pathogenesis of adenocarcinoma and carcinoid components.

GNEN-1: a spontaneously immortalized cell line from gastric neuroendocrine neoplasia

Mixed neuroendocrine-non-neuroendocrine neoplasms (MINEN) are rare tumors that consist of at least 30% of both neuroendocrine and non-neuroendocrine components. The data concerning the pathogenesis of MINEN suggest a monoclonal origin. We describe a spontaneously immortalized cell line derived from gastric MINEN called GNEN-1. Primary tumor consisted of components of high-grade neuroendocrine carcinoma and adenocarcinoma. The GNEN-1 cell line was initiated from metastatic tumor cells of peritoneal fluid and expresses a purely neuroendocrine phenotype. The GNEN-1 cell line grows as monolayers and has retained the neuroendocrine phenotype with positivity for chromogranin A in immunohistochemistry. Electron microscopy showed cytoplasmic dense core granules and axon hillocks. The karyotype revealed alterations typical of both adenocarcinoma and neuroendocrine carcinoma such as trisomy 7 and 8. GNEN-1 cells were also positive for stanniocalcin-1, a marker of poor prognosis in gastric carcinomas. Expression of several markers related to neuroendocrine tumors was found. There have been only a few studies on the pathogenesis of MINEN and management of the disease due to the rarity of this tumor type. Here we describe for the first time an immortalized cell line derived from mixed gastric NEN. The GNEN-1 line offers a tool for future research on gastric NEN.

Clinicopathologic and Molecular Characteristics of Gastrointestinal MiNENs

Background

A mixed neuroendocrine–non-neuroendocrine neoplasm (MiNEN) is a recently defined entity that comprises a neuroendocrine tumor (NEN) component and a non-neuroendocrine tumor (nNEN) component. As MiNEN is a recently defined entity, its molecular nature is not well known. Here, we evaluated the clinicopathologic and molecular characteristics of gastrointestinal (GI) MiNENs.

Methods

We performed a genomic analysis of 31 samples from 12 GI MiNEN cases using next-generation sequencing. We examined the primary NEN and nNEN components, as well as the metastatic NENs and nNENs. The relationships between the clinical tumor features (component, location, and grade) and their molecular characteristics were examined.

Results

The 12 MiNENs included in the study were found in the stomach (n=10), distal rectum (n=1), and anus (n=1). Primary MiNENs that had NENs as the major component showed a worse clinical outcome than those that had nNENs as the major component. All distant metastatic tumors originating from MiNENs were NENs. In addition, NENs generally carried 1.5 times more gene mutations and copy number variations than nNENs. The ATRX gene deletion and TP53 gene mutation were the most common variants in both components of GI MiNENs.

Conclusions

We have revealed the detailed clinicopathologic and molecular findings with distinguishable alterations of GI MiNENs. To our knowledge, this is the first study to report the ATRX gene deletion in GI MiNENs. The molecular characteristics of GI MiNENs could provide clues to the pathogenic origin and progression of GI MiNENs.

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.

Chromosomal and molecular pathway alterations in the neuroendocrine carcinoma and adenocarcinoma components of gastric mixed neuroendocrine-nonneuroendocrine neoplasm

Gastric mixed adenoneuroendocrine carcinoma (MANEC) is a clinically aggressive subtype of mixed neuroendocrine-nonneuroendocrine neoplasm (MiNEN) with unclear clonal origin. In this study, we analyzed high-resolution copy number (CN) profiling data using the OncoScan CNV Assay in the neuroendocrine carcinoma (NEC) and adenocarcinoma components of eight MANECs. Some common CNVs, including the gain of CCNE1 (19q12) and the loss of FAT1 (4q35.2), were frequently detected in both components; these CNVs were verified by FISH, qPCR and immunohistochemistry staining assays in samples with sufficient material. The identification of common CNVs in both components supports the likelihood of single clonal origin of morphologically heterogeneous tumor cells and suggests several novel genetic events potentially involved in the development of gastric MANEC. We also detected and validated some CNVs and alterations specific for the NEC component, such as MAPK1 loss and MAPK signaling pathway alterations, which could contribute to the neuroendocrine differentiation of gastric MANEC. In addition, we found that the NEC component presented more CNVs and greater CN loss than the adenocarcinoma component (P = 0.007 and P = 0.004, respectively); the NEC components from different cases were not clustered in the hierarchical clustering analysis, indicating the marked genetic heterogenicity of the NEC component in gastric MANEC. In summary, this study describes the cytogenetic characteristics of each component of gastric MANEC, providing some clues for further studies on the development and progression of gastric MANEC as well as providing some potential therapeutic targets.

Dilemmas in Diagnosis and Management of Gastroenteropancreatic Mixed Neuroendocrine Non-neuroendocrine Neoplasms: First Single-Centre Report from India

PURPOSE

Mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) is a rare neoplasm comprising of exocrine and neuroendocrine elements, each representing ≥ 30% lesion. It is commonly misdiagnosed as adenocarcinoma or grade-3 neuroendocrine neoplasm (NEN). Management is not well-defined.

METHODS

Retrospective analysis of prospectively entered data at our centre from January 2011 to January 2018 revealed 16 MiNENs off 130 neuroendocrine neoplasms (NENs). These were analysed for demographics, clinicopathological characteristics, management strategies and prognosis.

RESULTS

Four out of 16 patients, metastatic at presentation, were started on chemotherapy. Eleven of remaining 12 patients had pre-operative biopsy. Only two were diagnosed MiNEN. Four patients (33.34%) received 5-fluorouracil (5-FU)-based neoadjuvant chemotherapy and underwent curative surgery with adjuvant cisplatin+etoposide (Cis-Eto). Out of these, two patients (16.6%) developed metastasis and were shifted to capecitabine+temozolomide (Cap-Tem). Six patients (50%) with neuroendocrine-dominant MiNEN received adjuvant Cis-Eto after surgery. Two (16.6%) developed metastases for which Cap-Tem was started. One of them developed locoregional and liver metastasis. Three patients (25%) have succumbed to progressive disease, three (25%) are on treatment, and six (50%) are disease-free at 4-30 months.

CONCLUSION

Preoperative diagnosis of MiNEN is challenging, and it needs quality histopathological examination and immunohistochemistry. The 30% criteria is therapeutically insignificant, and treatment based on most aggressive component is prognostically more relevant. Neoadjuvant 5-FU-based regimens may downstage adenocarcinoma-dominant tumours. There are no guidelines on adjuvant Cis-Eto. Cap-Tem can be considered second-line chemotherapy. Poor survival is reported irrespective of site of origin and adjuvant therapy.

Comprehensive genetic features of gastric mixed adenoneuroendocrine carcinomas and pure neuroendocrine carcinomas

We aimed to determine the pathogenesis of gastric mixed adenoneuroendocrine carcinoma (MANEC) and pure neuroendocrine carcinoma (NEC), which is largely unknown. Targeted DNA sequencing was performed on 34 tumor samples from 21 patients - 13 adenocarcinoma (ADC)/NEC components from MANECs and eight pure NECs - and 21 matched non-neoplastic gastric tissues. Mutational profiles of MANECs/NECs were compared with those of other tumors using public databases. The majority (64.1%; 59/92) of mutations in MANEC were shared by both ADC and NEC components. TP53 was the most commonly mutated gene in MANEC (69.2%, 9/13) and pure NEC (87.5%, 8/9). All TP53 mutations in MANEC were pathogenic mutations and were shared by both ADC and NEC components. A subset of TP53^WT MANECs had a microsatellite-unstable phenotype or amplifications in various oncogenes including ERBB2 and NMYC, and the only TP53^WT pure NEC harbored MYC amplification. Compared to NEC in other organs, NECs arising from the stomach had unique features including less frequent RB1 mutations. Differentially altered genes of MANEC ADC components were significantly associated with receptor tyrosine kinase signaling pathways, while differentially altered genes of MANEC NEC components were significantly associated with the NOTCH signaling pathway. Our data provide evidence suggesting a possible clonal origin of ADC and NEC components of MANEC, and we found that gastric MANECs and pure NECs are distinct entities with unique mutational profiles and underlying protein networks. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

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.

Comparison of overall survival of gastric neoplasms containing neuroendocrine carcinoma components with gastric adenocarcinoma: a propensity score matching study

BACKGROUND

Gastric neoplasms containing neuroendocrine carcinoma (NEC) components are rare malignancies with highly aggressive behavior and a poor prognosis and include pure NEC and mixed tumors containing NEC components. We aimed to investigate whether there is a distinct difference in overall survival (OS) between gastric neoplasms containing NEC components and gastric adenocarcinoma.

METHODS

Surgically resected gastric neoplasms containing NEC components (n = 180) and gastric adenocarcinomas (n = 785) from January 2013 to December 2019 at Peking University Cancer Hospital were retrospectively analysed. Patients were categorized into a surgical group and a neoadjuvant group and adjusted using propensity score matching. In the two groups, gastric neoplasms containing NEC components were divided into pure NEC and mixed tumors with less than 30% (< 30% G-HMiNEN), between 30 and 70% (G-HMiNEN) and more than 70% (> 70% G-HMiNEN) neuroendocrine carcinoma components. OS was compared between these groups and the gastric adenocarcinoma group.

RESULTS

The OS of gastric neoplasms containing neuroendocrine NEC components was poorer than that of gastric adenocarcinomas in the surgical group, regardless of whether the percentage of neuroendocrine cancer components was less than 30%, between 30 and 70%, more than 70% or 100%. Cox multivariable regression analysis suggested that tumor category (neoplasms containing NEC components or gastric adenocarcinoma) was an independent risk factor for prognosis. Interestingly, among patients receiving neoadjuvant therapy, the difference was not significant.

CONCLUSIONS

Gastric neoplasms containing any proportion of NEC components had poorer overall survival than gastric adenocarcinoma in patients treated with surgery directly, indicating that these neoplasms are more malignant than gastric adenocarcinoma. Among the patients receiving neoadjuvant therapy, the difference in overall survival was not significant, which was in sharp contrast with the results of the surgery group, suggesting that neoadjuvant therapy may have a good effect in the treatment of these neoplasms.

Mixed adenoneuroendocrine carcinoma of the liver: A rare case report

A 55-year-old woman presented with chest and back pain of unknown cause. Contrast-enhanced computed tomography revealed two low-density tumors, sized 4.6 and 4.4 cm, in the hepatic caudate and left inner lobes, respectively. There are multiple enlarged lymph nodes around the abdominal aorta, hepatogastric ligament and gastrosplenic ligament. At the same time, there were multiple enlarged lymph nodes between the portal vein and the vena cava. Upper gastrointestinal endoscopy revealed chronic non-atrophic gastritis and esophagitis (grade B). Endoscopic examination of the lower digestive tract revealed polyps of the colon, diagnosed as tubular adenomas following biopsy and histopathological examination. The patient underwent left three hepatic resection (including left inner lobe, left outer lobe and right anterior lobe resection), abdominal lymph node dissection, right liver tumor radiofrequency ablation, hepatic caudate lobe resection, intestinal adhesion release, vena cava formation, portal vein repair and hilar cholangioplasty. The pathological examination of the resected specimens revealed intrahepatic bile duct carcinoma and hepatic parenchymal neuroendocrine tumor (NET). In addition, liver solid portions consisted of tumor cells with characteristic salt-and-pepper nuclei. Immunohistochemical examination revealed expression of the neuroendocrine marker synaptophysin in this solid component, confirming the diagnosis of NET. Furthermore, the MIB-1 proliferation index of the NET was higher compared with that of the adenocarcinoma, and lymph node invasion by the NET component was detected, indicating a neuroendocrine carcinoma (NEC, or NET G3). The diagnosis of mixed adenoneuroendocrine carcinoma of the liver was confirmed based on the World Health Organization 2010 criteria. Taking into consideration the patient's poor general condition, only symptomatic supportive treatment was administered postoperatively, without chemotherapy. Contrast-enhanced computed tomography at 45 days postoperatively revealed disease progression, with metastases in the liver stump, abdominal lymph nodes, spine and pelvis. The patient remained on symptomatic supportive treatment and succumbed to disease progression 3 months after surgery.

The Significant Influence of the Neuroendocrine Component on the Survival of Patients with Gastric Carcinoma Characterized by Coexisting Exocrine and Neuroendocrine Components

Background

Gastric adenocarcinoma patients with a neuroendocrine (NE) component are frequently observed in routine practice. Several previous studies have investigated the influence of a NE component on the survival of these patients; however, the results were inconsistent.

Methods

We retrospectively investigated a consecutive series of 95 gastric adenocarcinoma patients with a NE component and 190 gastric adenocarcinoma patients without a NE component. We adopted 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, and 90% as the cut-off proportions of the NE component, respectively, and analyzed the patients' overall survival according to the proportion of the NE component.

Results

The 1-, 3-, and 5-year actual survival rates of the patients with a NE component were 90.1%, 72.3%, and 67.2%, respectively, and for those without a NE component 94.2%, 79.3%, and 75.7%, respectively. The multivariate analysis showed that the patients with NE components >70% (HR: 2.156; 95% CI: 1.011, 4.597; p=0.047) and >90% (HR: 2.476; 95% CI: 1.088, 5.634; p=0.031) had significantly worse survival than those without a NE component. Only the diameter of tumors (>4.64 cm) (HR: 2.585; 95% CI: 1.112, 6.006; p=0.027) and pN3 (HR: 2.953; 95% CI: 1.051, 8.293; p=0.040) were independently associated with worse overall survival for gastric adenocarcinoma patients with a NE component (all p<0.05).

Conclusion

Gastric adenocarcinoma patients with a NE component >70% and >90% have significantly worse survival than those without a NE component. Only the diameter of tumors and the number of metastatic lymph nodes are independent prognostic factors for gastric adenocarcinoma patients with a NE component.

Analysis of Gastric Carcinoma With Neuroendocrine Character

The clinical significance of gastric adenocarcinoma with neuroendocrine differentiation is unclear because of its rarity. The aim of this study was to suggest a treatment strategy for this tumor. A total of 10 resected gastric tumors with neuroendocrine character, including 3 neuroendocrine carcinomas (NECs) and 7 adenocarcinomas with neuroendocrine differentiation, were retrospectively reviewed regarding tumor characteristics and therapeutic outcomes. The gastric adenocarcinomas with neuroendocrine differentiation had high rates of lymph node metastasis and vessel invasion, and showed the poor prognoses as NEC. The median survival time (MST) was 13 months. Preoperative and postoperative chemotherapy tended to prolong the MST compared with operation alone (112.5 versus 5 months; P = 0.058). Moreover, chemotherapy for postoperative recurrence significantly contributed to improving prognosis (MST, 15 versus 7 months; P = 0.025). Gastric adenocarcinoma with neuroendocrine differentiation had equivalently high potential malignancy as NEC. More aggressive treatment should be considered for this tumor according to NEC.

Prognostic factors for survival after curative resection of gastric mixed adenoneuroendocrine carcinoma: a series of 80 patients

BACKGROUND

To assess the prognostic factors and investigate the optimal treatment of gastric mixed adenoneuroendocrine tumors.

METHODS

We retrospectively analyzed clinical data from 80 patients with gastric mixed adenoneuroendocrine carcinoma that received radical resection in our department from January 2007 to December 2016. Risk factors for relapse and survival were analyzed using a multivariate Cox proportional hazards regression model. Gastric mixed adenoneuroendocrine carcinoma was divided into neuroendocrine carcinoma and adenocarcinoma based on the predominant type in the tumor.

RESULTS

The 3-year overall survival was 40% in the neuroendocrine carcinoma group and 75% in the adenocarcinoma group (P = 0.006). The neuroendocrine carcinoma (NEC)-dominant tumors and a Ki-67-positive index ≥60% were independent risk factors for worse overall survival. The 3-year recurrence-free survival was 33% in the neuroendocrine carcinoma group and 68% in the adenocarcinoma group. NEC-dominant tumors and a Ki-67-positive index ≥60% were independent risk factors for gastric mixed adenoneuroendocrine carcinoma recurrence. Patients in the adenocarcinoma group that received adjuvant chemotherapy exhibited significantly better overall survival than patients that did not receive chemotherapy (median survival time 43 months vs. 13 months, P = 0.026).

CONCLUSION

The NEC-dominant tumors and a Ki-67-positive index ≥60% were significantly associated with worse survival and a higher recurrence rate for gastric mixed adenoneuroendocrine carcinoma patients. Patients in the adenocarcinoma group may benefit from gastric adenocarcinoma treatments.

Synchronous Triple Gastric Cancer Incorporating Mixed Adenocarcinoma and Neuroendocrine Tumor Completely Resected with Endoscopic Submucosal Dissection

The endoscopic and pathological features of early gastric mixed adenoneuroendocrine carcinoma (MANEC), as well as its carcinogenesis, remain largely unclear. Screening esophagogastroduodenoscopy was performed on an 80-year-old man, revealing 3 superficial elevated lesions. Endoscopic submucosal dissection (ESD) was performed, and the patient was diagnosed with intramucosal gastric cancer comprising mixed adenocarcinoma and neuroendocrine tumor, well-differentiated adenocarcinoma and well-differentiated adenocarcinoma, with negative margins. To our knowledge, this is the first report describing the endoscopic and pathological findings of synchronous triple gastric cancer incorporating mixed adenocarcinoma and neuroendocrine tumor completely resected with ESD.

Mixed adenoneuroendocrine carcinoma of the colon and rectum

Mixed adenoneuroendocrine carcinoma (MANEC) are rare cancers of the gastrointestinal (GI) and pancreatobiliary tract. They are characterized by the presence of a combination of epithelial and neuroendocrine elements, where each component represents at least 30% of the tumour. Review of literature and consolidation of clinicopathological data. Sixty-one cases of colorectal MANEC have been reported in literature and one seen in this centre. The median age of the patients affected was 61.9 ± 12.4 years (20-94 years). Male to female ratio is 1.0:1.2. Presentations were similar to other colorectal malignancies. 58.0% of colorectal MANECs were found in the right colon, 8.1% cases in the transverse, 16.1% in the left colon, 16.1% in the rectum. These tumours appeared invasiveness 79.1% were T3-T4. Over 90% of cases were presented with metastatic disease. The majority of patient underwent surgical resection of the primary cancer (96.6%). Of these, 10 operations (17.9%) were emergency operations due to obstruction, perforation, or bleeding. Three patients received first line palliative care. In eight cases (13.8%), patients underwent adjuvant chemotherapy. The median overall survival after diagnosis was 10 ± 2.4 months (95% CI: 5.37-14.64 months). MANECs are rare but aggressive colorectal cancers. Surgical resection of localized disease with adjuvant chemotherapy appears to significantly improve survival in small case series. Further understanding through the sharing of experiences is required.

Mixed adenoneuroendocrine carcinoma of the esophagogastric junction: a case report

Background

Mixed adenoneuroendocrine carcinoma (MANEC) is a tumor of the gastrointestinal tract that contains both exocrine and endocrine components, with each component exceeding 30% of the total tumor area. Because MANECs are exceedingly rare, no therapeutic strategies have been established yet.

Case presentation

An 81-year-old man was referred to our hospital with a 5-month history of dysphagia. Esophagogastroduodenoscopy revealed an ulcerated mass in the lower thoracic esophagus, extending up to the esophagogastric junction (33 to 40 cm from the incisors). The initial biopsy diagnosis was adenocarcinoma. Computed tomography revealed no evidence of lymph node or distant metastasis. The patient was treated by thoracoscopic esophagectomy with three-field lymph node dissection and gastric tube reconstruction via a posterior mediastinal approach, under the diagnosis of esophagogastric junctional cancer (T3N0M0, stage IIA). Histopathological examination revealed two distinct components, namely, a neuroendocrine carcinoma component and an adenocarcinoma component, and the patient was diagnosed as having mixed adenoneuroendocrine carcinoma (MANEC). He presented with liver metastasis 6 months after the surgery. Thereafter, the tumor became even more aggressive, and the patient died 8 months after the surgery.

Conclusions

We report a patient with MANEC of the esophagogastric junction. Close attention should be paid to such patients, as MANEC can be a highly aggressive tumor, showing rapid progression. In the treatment of MANEC, it is necessary to carefully consider the pathological features in each individual case.

Multiregion Comprehensive Genomic Profiling of a Gastric Mixed Neuroendocrine-Nonneuroendocrine Neoplasm with Trilineage Differentiation

Mixed neuroendocrine-nonneuroendocrine neoplasms (MiNENs) are a group of rare tumors previously known as mixed adenoneuroendocrine carcinomas (MANECs). The neuroendocrine component is high-grade and may consist of small-cell carcinoma or large-cell neuroendocrine carcinoma. The nonneuroendocrine component may consist of adenocarcinoma or squamous cell carcinoma. We report a unique case of a MiNEN with trilineage differentiation: large-cell neuroendocrine carcinoma, squamous cell carcinoma, and adenocarcinoma. The reported patient presented with symptoms of an upper gastrointestinal bleed and was ultimately diagnosed with a MiNEN with trilineage differentiation. This is the first report of this exceedingly rare tumor type to include next-generation sequencing of the 3 separate tumor entities. In addition, we review the current literature and discuss the role of next-generation sequencing in classifying and treating MiNEN tumors.

Ki67 proliferative index of the neuroendocrine component drives MANEC prognosis

Mixed adenoneuroendocrine carcinomas (MANECs) are composed of a poorly differentiated neuroendocrine carcinoma (NEC) and a non-neuroendocrine (non-NEC) neoplastic epithelial component, each representing at least 30% of the tumor. At present, prognostic factors for MANECs remain largely unexplored. We investigated the clinical-pathologic features of a large multicenter series of digestive system MANECs. Surgical specimens of 200 MANEC candidates were centrally reviewed; diagnosis was confirmed in 160 cases. While morphology, proliferation (mitotic count (MC), Ki67 index) and immunophenotype (p53, SSTR2a, beta-Catenin, Bcl-2, p16, Rb1, ALDH, mismatch repair proteins and CD117) were investigated separately in both components, genomic (TP53, KRAS, BRAF) alterations were searched for on the entire tumor. Data were correlated with overall survival (OS). MANEC sites were: 92 colorectal, 44 gastroesophageal and 24 pancreatobiliary. Median OS was 13.2 months. After adjustment for primary site, Ki67 index of the NEC component (but not of the non-NEC component) was the most powerful prognostic marker. At multivariable analysis, patients with Ki67 ≥ 55% had an 8-fold risk of death (hazard ratio (HR) 7.83; 95% confidence interval (CI) 4.17-14.7; P < 0.0001) and a median OS of 12.2 months compared to those with Ki67 < 55% (median OS 40.5 months). MC (HR 1.51; 95% CI 1.03-2.20, P = 0.04) was a weaker prognostic index. Colorectal primary site (HR 1.60; 95% CI 1.11-2.32; P = 0.01) was significantly associated with poorer survival. No single immunomarker, in either component, was statistically significant. This retrospective analysis of a large series of digestive system MANECs, showed that the NEC component, particularly its Ki67 index, was the main prognostic driver.

Neuroendocrine-like cells -derived CXCL10 and CXCL11 induce the infiltration of tumor-associated macrophage leading to the poor prognosis of colorectal cancer

Our previous study revealed that neuroendocrine differentiation in colorectal cancer is one of the important factors leading to worse prognosis. In this study, we apply immunohistochemical staining, Western-blot, RT-PCR and ELISA to investigate the underlying mechanism that how the neuroendocrine differentiation to affect the prognosis of colorectal cancer. The interaction of colorectal cancer cells, neuroendocrine-like cells and tumor-associated macrophages in colorectal cancer progress is also investigated. By analyzing 82 cases of colorectal cancer patients treated in our institution, we found that colorectal adenocarcinoma with neuroendocrine differentiation had increasing number of tumor-associated macrophages and worse prognosis. Further evaluation of cytology showed that neuroendocrine cells have the ability to recruit tumor-associated macrophages to infiltrate the tumor tissue, and the tumor-associated macrophages enhance the proliferation and invasion abilities of the colon cancer cells. Moreover, we confirmed that CXCL10 and CXCL11 are the key chemokines in neuroendocrine-like cells and they promote the chemotaxis activity of tumor-associated macrophages. The secretion of CXCL10 and CXCL11 by neuroendocrine-like cells can recruit tumor-associated macrophages to infiltrate in tumor tissues. The latter enhances the proliferation and invasion of colorectal cancer cell and lead to poor prognosis.

Gastric Pouch Mixed Adenoneuroendocrine Carcinoma With a Mixed Adenocarcinoma Component After Roux-en-Y Gastric Bypass

The Roux-en-Y gastric bypass is one of the most common procedures currently performed for surgical treatment of patients with severe obesity. Gastric cancer after bariatric surgery is not common, with most of them arising in the excluded stomach. Gastric mixed adenoneuroendocrine carcinomas are a rare type of stomach malignancy, composed of both adenocarcinoma and neuroendocrine tumor-cell components, with the latter comprising at least 30% of the whole neoplasm. In this article, we report a unique case of a mixed adenoneuroendocrine carcinoma with a mixed adenocarcinoma (tubular and poorly cohesive) component arising in the gastric pouch of a patient who underwent previous Roux-en-Y gastric bypass for glycemic control. Since stomach cancer is not usual in patients who have formerly undergone bariatric surgery and symptoms tend to be nonspecific, such diagnosis is often rendered at an advanced stage. Full assessment of these patients when presenting such vague symptoms is critical for an early cancer diagnosis.

Characterization of genome-wide copy number aberrations in colonic mixed adenoneuroendocrine carcinoma and neuroendocrine carcinoma reveals recurrent amplification of PTGER4 and MYC genes

Colonic mixed adenoneuroendocrine carcinoma (MANEC) is an aggressive neoplasm with worse prognosis compared with adenocarcinoma. To gain a better understanding of the molecular features of colonic MANEC, we characterized the genome-wide copy number aberrations of 14 MANECs and 5 neuroendocrine carcinomas using the OncoScan FFPE (Affymetrix, Santa Clara, CA) assay. Compared with 269 colonic adenocarcinomas, 19 of 42 chromosomal arms of MANEC exhibited a similar frequency of major aberrant events as adenocarcinomas, and 13 chromosomal arms exhibited a higher frequency of copy number gains. Among them, the most significant chromosomal arms were 5p (77% versus 13%, P = .000012) and 8q (85% versus 33%, P = .0018). The Genomic Identification of Significant Targets in Cancers algorithm identified 7 peaks that drive the tumorgenesis of MANEC. For all except 5p13.1, the peaks largely overlapped with those of adenocarcinoma. Two tumors exhibited MYC amplification localized in 8q24.21, and 2 tumors exhibited PTGER4 amplification localized in 5p13.1. A total of 8 tumors exhibited high copy number gain of PTGER4 and/or MYC. Whereas the frequency of MYC amplification was similar to adenocarcinoma (10.5% versus 4%, P = .2), the frequency of PTGER4 amplification was higher than adenocarcinoma (10.5% versus 0.3%, P = .01). Our study demonstrates similar, but also distinct, copy number aberrations in MANEC compared with adenocarcinoma and suggests an important role for the MYC pathway of colonic carcinoma with neuroendocrine differentiation. The discovery of recurrent PTGER4 amplification implies a potential of exploring targeting therapy to the prostaglandin synthesis pathways in a subset of these tumors.

Genetic basis of a common tumor origin in the development of pancreatic mixed acinar-neuroendocrine-ductal carcinoma: A case report

Pancreatic cancer is classified as ductal, acinar, neuroendocrine carcinoma or pancreatoblastoma. Ductal and acinar cells derive from exocrine glands and neuroendocrine cells from endocrine glands; however, mixed acinar-neuroendocrine-ductal carcinoma has different histological carcinomas coexisting within a nodule. The mixed pancreatic carcinoma forms from different developmental origins and therefore requires investigation. The current case report presents a 50-year-old male who had a tumor within the body of the pancreas. Pathological examination clarified the tumor as a mixed acinar-neuroendocrine-ductal carcinoma. The ductal and acinar/neuroendocrine tumor components were isolated using laser-capture microdissection, and next-generation sequencing analysis was performed. Consequently, TP53 frameshift (p.N210fs) and KRAS missense (p.G12R) mutations were identified in both ductal and acinar/neuroendocrine tumors. These results suggested a pancreatic mixed acinar-neuroendocrine-ductal carcinoma was derived from a founder tumor clone, and supports the notion that a founder tumor clone may differentiate and transform into a diverse histological type and form a pancreatic mixed carcinoma.

Ampullary Mixed Adenoneuroendocrine Carcinoma: Surprise Histology, Familiar Management

INTRODUCTION

Mixed adenoneuroendocrine carcinoma (MANEC) has recently been defined by the World Health Organization in 2010. These are rare tumors and MANECs of ampullary region are even rarer. Only 19 cases have been reported in literature. We present 3 cases; the largest series, second case of amphicrine tumor and first case associated with chronic pancreatitis.

METHODS

Retrospective review of 3 patients who were diagnosed to have ampullary MANEC.

RESULTS

All 3 patients were diagnosed preoperatively as neuroendocrine carcinoma and underwent margin negative pancreaticoduodenectomy. The histopathology revealed MANECs of small cell, mixed type in 2 patients and large cell, amphicrine type in 1 patient. The neuroendocrine component was grade 3 in all, the tumor was T3 in 2 and T2 in 1 and all had nodal metastases. Two patients received adjuvant chemotherapy and 2 of them had recurrence at 13 and 16 months. The median survival was 15 months.

CONCLUSION

Ampullary MANECs are rare tumors. They are diagnosed on histopathologic examination of the resected specimen. Clinical presentation, management, and prognosis is similar to ampullary adenocarcinoma in literature.

In-depth mutational analyses of colorectal neuroendocrine carcinomas with adenoma or adenocarcinoma components

Neuroendocrine carcinomas (NECs) of the colorectum are rare but highly aggressive neoplasms. These tumors show some shared genetic alterations with colorectal adenocarcinomas, and most of them have adjacent glandular adenoma or adenocarcinoma components. However, genetic data on colorectal NECs still are sparse and insufficient for definite conclusions regarding their molecular origin. Based on morphological characterization, panel and whole-exome sequencing, we here present results from an in-depth analysis of a collection of 15 colorectal NECs with glandular components, 10 of which by definition were mixed adenoneuroendocrine carcinomas (MANECs). Among shared genetic alterations of both tumor components, we most frequently found TP53, KRAS and APC mutations that also had highest allele frequencies. Mutations exclusive to glandular or neuroendocrine components outnumbered shared mutations but occurred at lower allele frequencies. Our findings not only provide additional evidence for a common clonal origin of colorectal NECs and adjacent glandular tumor components, but strongly suggest their development through the classical adenoma-carcinoma sequence. Moreover, our data imply early separation of glandular and neuroendocrine components during malignant transformation with subsequent independent mutational evolution.

Mixed Neuroendocrine-Nonneuroendocrine Neoplasms (MiNENs): Unifying the Concept of a Heterogeneous Group of Neoplasms

The wide application of immunohistochemistry to the study of tumors has led to the recognition that epithelial neoplasms composed of both a neuroendocrine and nonneuroendocrine component are not as rare as traditionally believed. It has been recommended that mixed neuroendocrine-nonneuroendocrine epithelial neoplasms are classified as only those in which either component represents at least 30 % of the lesion but this cutoff has not been universally accepted. Moreover, since their pathogenetic and clinical features are still unclear, mixed neuroendocrine-nonneuroendocrine epithelial neoplasms are not included as a separate clinicopathological entity in most WHO classifications, although they have been observed in virtually all organs. In the WHO classification of digestive tumors, mixed neuroendocrine-nonneuroendocrine neoplasm is considered a specific type and is defined as mixed adenoneuroendocrine carcinoma, a definition that has not been accepted for other organs. In fact, this term does not adequately convey the morphological and biological heterogeneity of digestive mixed neoplasms and has created some misunderstanding among both pathologists and clinicians. In the present study, we have reviewed the literature on mixed neuroendocrine-nonneuroendocrine epithelial neoplasms reported in the pituitary, thyroid, nasal cavity, larynx, lung, digestive system, urinary system, male and female genital organs, and skin to give the reader an overview of the most important clinicopathological features and morphological criteria for diagnosing each entity. We also propose to use the term "mixed neuroendocrine-nonneuroendocrine neoplasm (MiNEN)" to define and to unify the concept of this heterogeneous group of neoplasms, which show different characteristics mainly depending on the type of neuroendocrine and nonneuroendocrine components.

A Previously Undescribed Presentation of Mixed Adenoneuroendocrine Carcinoma

We report a case of mixed adenoneuroendocrine carcinoma (MANEC) of stomach with tubular adenoma and well-differentiated neuroendocrine tumor (WD-NET) in the primary tumor in the stomach giving rise to biphenotypic regional nodal metastases. A 35-year-old woman with abdominal pain was found to have a 1.8-cm gastric lesion, diagnosed as WD-NET (intermediate grade) on the biopsy. The resection specimen contained residual WD-NET; there was also a gastric adenoma adjacent to the NET and nodal metastasis with both adeno- and neuroendocrine components. The tumor was classified as MANEC. Of note, the entire gastric tissue was submitted and multiple deeper levels of the adenomatous lesion were examined; no adenocarcinoma was present in the primary lesion. While association of gastric adenoma with neuroendocrine neoplasm is rare, presence of biphenotypic metastasis originating from such a lesion is highly unusual and to the best of our knowledge has not been reported.

Gastric mixed adenoneuroendocrine carcinoma: correlation of histologic characteristics with prognosis

Gastric mixed adenoneuroendocrine carcinomas (MANECs) are rare, with both the exocrine and neuroendocrine components exceeding 30% volume. Several classifications for MANECs have been proposed, yet they have not been clinically evaluated. The aim of this study was to evaluate the correlation between tumor grade, histologic characteristics, and prognosis of gastric MANECs. We collected eligible 14 cases in our series and 31 cases in the literature and compared the prognostic difference among gastric MANECs with different histologic characteristics. Gastric MANECs could be divided into subgroups according to tumor grade of the neuroendocrine component and adenocarcinoma types. The high grade and large proportion of neuroendocrine component correlated with aggressive behavior and a tendency of poor clinical outcome. Gastric MANECs with a poorly differentiated adenocarcinoma showed a significant lower survival rate than did MANECs with a differentiated adenocarcinoma or mucin-producing carcinoma (P = .0008). Gastric MANECs were a heterogeneous group with different tumor grades, histologic subtypes, combination patterns, and patient outcomes. Previous classifications were evaluated. This study proves that histologic characteristics correlate with clinical outcomes. Our findings are complements to the latest prognostic classification.

On the Origin of Cells and Derivation of Thyroid Cancer: C Cell Story Revisited

We will highlight and put into perspective new lineage tracing data from genetic studies in mice indicating that the genuine progenitors to C cells arise in the endoderm germ layer. This overturns the current concept of a neural crest origin of thyroid C cells referred to in every textbook and dedicated paper to this very day. As will become apparent, except for a single experiment, the neural crest theory has little or no support when the evolution and development of calcitonin-producing cells in the entire chordate family are considered. Instead, a unifying origin of all cells of the ultimobranchial bodies reopens questions on the histogenesis of certain thyroid pathologies previously difficult to explain. On this aspect, medullary thyroid cancer shows a stronger connection to gut neuroendocrine tumours than previously recognized. It is envisaged that novel factors implicated in C cell-derived tumour growth and progression will be discovered as the mechanisms that regulate lineage expansion of embryonic C cell precursors from pharyngeal endoderm are uncovered. We will not discuss why C cells go to the bother of burying themselves in the thyroid - this remains a mystery.

Primary high-grade neuroendocrine carcinoma emerging from an adenomatous polyp in the setting of familial adenomatous polyposis

Familial adenomatous polyposis (FAP) is a rare inherited syndrome that is characterised by innumerable adenomas of the colon and rectum, a high risk of colorectal cancer and a variety of extracolonic manifestations. FAP presents as hundreds to thousands of colonic adenomas beginning in adolescence. The syndrome is associated with less than 1% of all colorectal cancer cases, but there is a nearly 100% lifetime risk of colorectal cancer in individuals with FAP. This case demonstrates a 60-year-old man with FAP who developed high-grade neuroendocrine carcinoma with glandular and squamous differentiation, and regional lymph node and liver metastases. Early diagnosis of FAP is of the utmost importance to start screening colonoscopies to assess disease burden, perform polypectomies and to make management decisions. Neuroendocrine carcinomas rarely occur in patients with FAP, and awareness of this association among general medical physicians and pathologists is essential for the diagnosis and care of these patients.

Republished: gastric neuroendocrine neoplasms and related precursor lesions

Gastric neuroendocrine neoplasms (NENs) are a heterogeneous group of tumours showing different clinicopathological features and behaviour, implying a wide spectrum of therapeutic options. They are currently classified using the 2010 WHO classification of digestive neuroendocrine neoplasms into G1-neuroendocrine tumours (NETs), G2-NETs, neuroendocrine carcinomas (NECs) and mixed adenoneuroendocrine carcinomas (MANECs). However, most gastric NENs are composed of ECL-cells (ECL-cell NETs) that can be preceded by ECL-cell hyperplastic and dysplastic lesions, whose oncologic potential has not yet been completely elucidated. ECL-cell NETs differ considerably in terms of prognosis depending on the proliferative status and clinicopathological background. The integration of both aspects in the diagnostic pathway may help to better classify tumours in different prognostic categories, especially when diagnosing them in small bioptic specimens. NECs are all poorly differentiated, highly aggressive carcinomas, while MANECs can show different morphological features that are directly associated with different prognoses. Precursor lesions of such carcinomas are not entirely understood. In this review, the clinicopathological features of gastric NENs and related precursor lesions will be described to give the reader a comprehensive overview on this topic.

Large cell neuroendocrine - Adenocarcinona mixed tumour of colon: Collision tumour with peculiar behaviour. What do we know about these tumours?

Introduction

Mixed glandular-endocrine carcinomas are rare tumours of gastrointestinal tract (MANEC). They are more frequent in stomach and hardly one hundred cases have been described in colon. According to Lewis, they are classified into collision (side by side pattern), composite (intermingled) or amphicrine (neuroendocrine and glandular features inside a same cell). Collision tumours are related to biclonal theory: two simultaneous cancerogenic events. Conversely, multidirectional differentiation from a stem cell is accepted as origin of composite tumours.

The aim of this paper is to analyse the behaviour of these tumours, with an especial concern about how these tumours metastasise, and the different theories about carcinogenesis.

Presentation of case

We report a rare case of collision adenocarcinoma-large cell neuroendocrine tumour of colon that after a three-year period of follow-up has presented a retroperitoneal recurrence that features adenocarcinoma and large cell neuroendocrine components.

Discussion

After an exhaustive review of the English literature, we found that only two cases of collision tumour of colon with metastases showing glandular and endocrine components have been described up to date, so we report the third case, and the first happening in transverse colon.

Conclusion

We conclude that not all collision tumours follow the biclonal theory and more studies are needed to clarify the origin of these neoplasms, and consequently, to reach an adequate treatment.

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MANEC are defined as mixed adenoneuroendocrine carcinoma.

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They are divided into composite and collision.

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The poorest differentiated component will determine the prognosis.

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Metastases occur frequently at liver and nodes.

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Colon is a very rare place.

Comparative genomic hybridization on microarray (a-CGH) in olfactory neuroblastoma: Analysis of ten cases and review of the literature

Olfactory neuroblastoma is a rare tumor arising from the basal layer of the olfactory epithelium in the superior recesses of the nasal cavity. The rarity of this tumor, and the difficulties in culturing tumor cells has limited the generation of conventional cytogenetic data, whereas consistent results have been obtained by recent molecular methods. We report the results of an array-based comparative genomic hybridization analysis (a-CGH) obtained on 11 samples from 10 subjects: 8 primary and 3 relapsed tumors. In one patient, both the primary and relapsed tumors were available. Our results on chromosome imbalances highlight the highly heterogeneous presentation: six of eleven samples showed multiple numerical changes and very few structural ones, while four samples showed an opposite pattern; one sample out of eleven showed no imbalances. We did not reach firm evidence of any recurrent specific imbalances either at level of entire chromosomes or chromosome segments. A review of the literature indicates a number of recurrent gains, and losses, mostly not confirmed by our results. Gain of chromosome 19 was the only correspondence with literature data concerning an entire chromosome, and most segmental gains and losses found in our cohort of patients were different from those indicated in the literature: the only similarities concerned the gain of 20q13 and the loss of segments of chromosomes 15 and 22.

Gastric collision tumors: an insight into their origin and clinical significance

Collision tumors are rare neoplasms displaying two distinct cell populations developing in juxtaposition to one another without areas of intermingling. They are rare entities with only 63 cases described in English literature. Tumors encountered are gastric adenocarcinomas colliding with lymphomas, gastrointestinal stromal tumors, squamous cell carcinomas, and neuroendocrine tumors. Their cell origin is obsolete by the time of diagnosis. Different tumorigenesis theories have been suggested to explain their behavior, yet none has managed to provide satisfactory explanation for all cases. Clinically they are indistinguishable from the dominant tumor. Lack of data does not allow detailed assessment of their behavior yet they seem aggressive neoplasms with dismal prognosis. The majority of cases have been diagnosed postoperatively during histologic examination of specimens. There are no guidelines or concrete evidence to support best way of adjuvant or other types of treatment. However, these rare neoplasms might help in unlocking secrets of cancer behavior including tumorigenesis, differentiation, and adhesion and thus clinicians should be aware of their existence.

Expression analysis of genes involved in DNA repair or synthesis in mixed neuroendocrine/nonneuroendocrine carcinomas

BACKGROUND

Mixed neuroendocrine/nonneuroendocrine carcinomas are heterogeneous tumors with poorly defined diagnostic and clinical features and without pathological or molecular markers of prognosis or markers predicting their response to therapy. We aimed at analyzing the pathological features and the expression of genes involved in DNA repair or synthesis in a cohort of patients with mixed carcinomas from different sites as compared to the patients' outcome.

METHODS

Relative cDNA quantification of ribonucleotide reductase, large subunit 1, excision repair cross-complementation group 1, thymidylate synthase and topoisomerase IIa genes was tested using real-time PCR on microdissected neuroendocrine and nonneuroendocrine tumor components of 42 mixed cases (from the lung as well as the gastrointestinal and genitourinary tracts) and on 45 control cases of pure neuroendocrine and nonneuroendocrine carcinomas.

RESULTS

The expression levels of all genes were stable comparing nonneuroendocrine and neuroendocrine components of mixed cases (except for topoisomerase IIa in lung samples) but significantly different as compared to control nonneuroendocrine and neuroendocrine tumors. In the multivariate analysis including all clinical and pathological parameters and gene expression levels available, a predominant nonneuroendocrine component, the administration of additional therapy other than surgery and a high thymidylate synthase expression in nonneuroendocrine tumor tissue were significantly associated with a lower risk of a patient's death.

CONCLUSIONS

Our data show that mixed neuroendocrine/nonneuroendocrine carcinomas are different at the molecular level from their pure neuroendocrine and nonneuroendocrine counterparts, and detailed analyses of their clinical, pathological and molecular features may improve the clinical strategies for the treatment of these rare and underestimated tumors.

Intramucosal gastric mixed adenoneuroendocrine carcinoma completely resected with endoscopic submucosal dissection

Composite tumors in the stomach composed of adenocarcinoma and neuroendocrine carcinoma are rare. We herein report a case of intramucosal gastric mixed adenoneuroendocrine carcinoma (MANEC) that was treated with endoscopic submucosal dissection (ESD). A 77-year-old man who had previously received ESD for early gastric adenocarcinoma underwent esophagogastroduodenoscopy for screening, which showed a depressed lesion on the lesser curvature of the antrum. The tumor was removed en bloc via ESD and pathologically diagnosed as MANEC. The tumor was located within the mucosal layer, and no lymphovascular invasion was evident. Seven months after the ESD procedure, the patient is currently feeling well without recurrence or metastasis.

Collision tumours of ovary: a very rare case series

Collision tumours are composed of two histologically distinct neoplasms in the same organ without intermixture of cell types. Here the author present a case series of 4 cases of collision tumours of ovary with brief review of literature. Two cases have a combination of mucinous cystadenoma and teratoma whereas third case is a combination of serous papillary cystadenoma with teratoma and the fourth case has a combination of serous papillary cystadenocarcinoma and teratoma. The cases were diagnosed post-operatively. It is important to correctly diagnose the component of tumour for further management and favourable prognosis.

Boveri at 100: cancer evolution, from preneoplasia to malignancy

In the 100 years since the publication of Boveri's manuscript, 'Concerning the origin of human tumours', we have seen many advances in our understanding of how tumours originate, develop and progress. However, reading this article now, it is possible to find conclusions, or more often predictions, of what we now consider basic tenets of tumour biology. These include predicting the stochastic nature of the malignant change and that all tumours are necessarily of clonal origin, perhaps the basis of the modern concepts of field cancerization, of tumour heterogeneity and the clonal evolution of tumours. Modern researchers rarely refer to this paper, yet as a source of ideas it must rank amongst the landmarks in tumour biology of the last 100 years.

Gastric neuroendocrine neoplasms and related precursor lesions

Gastric neuroendocrine neoplasms (NENs) are a heterogeneous group of tumours showing different clinicopathological features and behaviour, implying a wide spectrum of therapeutic options. They are currently classified using the 2010 WHO classification of digestive neuroendocrine neoplasms into G1-neuroendocrine tumours (NETs), G2-NETs, neuroendocrine carcinomas (NECs) and mixed adenoneuroendocrine carcinomas (MANECs). However, most gastric NENs are composed of ECL-cells (ECL-cell NETs) that can be preceded by ECL-cell hyperplastic and dysplastic lesions, whose oncologic potential has not yet been completely elucidated. ECL-cell NETs differ considerably in terms of prognosis depending on the proliferative status and clinicopathological background. The integration of both aspects in the diagnostic pathway may help to better classify tumours in different prognostic categories, especially when diagnosing them in small bioptic specimens. NECs are all poorly differentiated, highly aggressive carcinomas, while MANECs can show different morphological features that are directly associated with different prognoses. Precursor lesions of such carcinomas are not entirely understood. In this review, the clinicopathological features of gastric NENs and related precursor lesions will be described to give the reader a comprehensive overview on this topic.