Search

Little is known as to whether there may be any pathogenetic link between pulmonary carcinoids and neuroendocrine carcinomas (NECs). A gene signature we previously found to cluster pulmonary carcinoids, large cell neuroendocrine carcinoma (LCNEC) and small cell lung carcinoma (SCLC), and which encompassed MEN1, MYC, MYCL1, RICTOR, RB1, SDHA, SRC and TP53 mutations or copy number variations (CNVs), was used to reclassify an independent cohort of 54 neuroendocrine neoplasms (NENs) [31 typical carcinoids (TC), 11 atypical carcinoids (AC) and 12 SCLC], by means of transcriptome and mutation data. Unsupervised clustering analysis identified two histology-independent clusters, namely CL1 and CL2, where 17/42 (40.5%) carcinoids and all the SCLC samples fell into the latter. CL2 carcinoids affected survival adversely, were enriched in T to G transversions or T > C/C > T transitions in the context of specific mutational signatures, presented with at least 1.5-fold change (FC) increase of gene mutations including TSC2 , SMARCA2 , SMARCA4 , ERBB4 and PTPRZ1 , differed for gene expression and showed epigenetic changes in charge of MYC and MTORC1 pathways, cellular senescence, inflammation, high-plasticity cell state and immune system exhaustion. Similar results were also found in two other independent validation sets comprising 101 lung NENs (24 carcinoids, 21 SCLC and 56 LCNEC) and 30 carcinoids, respectively. We herein confirmed an unexpected sharing of molecular traits along the spectrum of lung NENs, with a subset of genomically distinct aggressive carcinoids sharing molecular features of high-grade neuroendocrine neoplasms. [ABSTRACT FROM AUTHOR]

Neuroendocrine tumors (NETs) and gastrointestinal stromal tumors (GISTs) are different tumor categories with no pathogenetic, morphologic, clinical, or therapeutic similarities: NETs are epithelial to neural tumors in contrast to GISTs, which show mesenchymal cell lineage. Both tumors, however, arise more frequently from the gastrointestinal tract and may benefit of specific target therapeutic approaches: imatinib/STI-571 for GISTs and m-Tor pathway inhibitors or somatostatin analogs for NETs. The role of pathologist is crucial when dealing with both NETs and GISTs, as morphological, immunohistochemical, and molecular analysis often provide helpful information on the clinical behavior and management. We here propose a general overview on nomenclature of tumors classification and suggestions for histological report of both NETs and GISTs. Moreover, we will approach in finer details the immunohistochemical analysis on origin and differential diagnosis in NETs as well as the prognosis and resistance to therapy in GISTs. This review emphasized recent literature advances regarding similarities and differences in the managerial pathologist's approach to either tumor type. [ABSTRACT FROM AUTHOR]

An estimated 20% to 30% of all neuroendocrine tumours originate in the bronchial tree and lungs. According to the 2015 World Health Organization categorization, these tumours are separated into four subtypes characterized by increasing biological aggressiveness: typical carcinoid, atypical carcinoid, large-cell neuroendocrine carcinoma and small-cell carcinoma. Although typical and atypical lung carcinoids account for less than 1–5% of all pulmonary malignancies, the incidence of these neoplasms has risen significantly in recent decades. Surgery is the treatment of choice for loco-regional disease but for advanced lung carcinoids there is no recognized standard of care and successful management requires a multidisciplinary approach. The aim of this review is to provide a useful guide for the clinical management of lung carcinoids. [ABSTRACT FROM AUTHOR]

Aims Primary Ewing sarcoma of the ileum has rarely been documented. Little is known about its pathogenesis and clinical implications, and it would be helpful to identify novel molecular markers. EWSR1-FEV translocation is exceedingly rare in Ewing sarcoma, as FEV expression is restricted to prostate, brain and serotonin neuroendocrine cells ( NE) and related tumours. Methods and Results Paraffin sections or snap-frozen material were used in this investigation. Tumours were investigated by means of immunohistochemistry, RT-PCR ( EWSR1- FLI1, EWSR1- ERG and EWSR1- FEV transcripts), FISH analysis ( EWSR1 break-apart and specific EWSR1- FEV translocation) and spectral karyotyping ( SKY). Ten ileal neuroendocrine tumours ( INET) made up the control group for EWSR1- FEV translocation. Among 445 Ewing sarcomas cases spanning a period of 20 years, seven (1.6%) arose in the ileum. All tumours were immunoreactive for synaptophysin, CD99, FLI1 and vimentin. FISH identified EWSR1 rearrangement in all cases, with EWSR1-FLI1 transcripts being detected in all but one tumour showing the uncommon EWSR1- FEV rearrangement, with SKY, RT- PCR and FISH confirmation. The mean survival of EWSR1- FLI1 patients was 14 months, whereas the EWSR1- FEV patient was alive after 15 years despite several recurrences controlled by surgery alone. No INET showed EWSR1 translocation. Conclusions Most primary Ewing sarcomas of the ileum show the common EWSR1- FLI1 translocation, but EWSR1- FEV could be specific for tumours arising in the ileum and showing better prognosis. [ABSTRACT FROM AUTHOR]

Abstract: Immunohistochemical loss of the succinate dehydrogenase subunit B (SDHB) has recently been reported as a surrogate biomarker of malignancy in sporadic and familial pheocromocytomas and paragangliomas through the activation of hypoxia pathways. However, data on the prevalence and the clinical implications of SDHB immunoreactivity in ileal neuroendocrine tumors are still lacking. Thirty-one consecutive, advanced primary midgut neuroendocrine tumors and related lymph node or liver metastases from 24 males and seven females were immunohistochemically assessed for SDHB. All patients were G1 tumors (Ki-67 labeling index ⩽2%). SDHB immunohistochemistry results were expressed as immunostaining intensity and scored as low or strong according to the internal control represented by normal intestinal cells. Strong positivity for SDHB, with granular cytoplasmatic reactivity, was found in 77% of primary tumors (T), whilst low SDHB expression was detected in 90% of metastases (M). The combined analysis (T+M) confirmed the loss of SDHB expression in 82% of metastases compared to 18% of primary tumors. SDHB expression was inversely correlated with Ki-67 labeling index, which accounted for 1.54% in metastastic sites and 0.7% in primary tumors. A correlation between SDHB expression loss, increased Ki-67 labeling index and biological aggressiveness was shown in advanced midgut neuroendocrine tumors, suggesting a role of tumor suppressor gene. [ABSTRACT FROM AUTHOR]

Background: Small intestine neuroendocrine tumors (SI-NETs) belong to a rare group of cancers. Most patients have developed metastatic disease at the time of diagnosis, for which there is currently no cure. The delay in diagnosis is a major issue in the clinical management of the patients and new markers are urgently needed. We have previously identified paraneoplastic antigen Ma2 (PNMA2) as a novel SI-NET tissue biomarker. Therefore, we evaluated whether Ma2 autoantibodies detection in the blood stream is useful for the clinical diagnosis and recurrence of SI-NETs. Methodology/Principal Findings: A novel indirect ELISA was set up to detect Ma2 autoantibodies in blood samples of patients with SI-NET at different stages of disease. The analysis was extended to include typical and atypical lung carcinoids (TLC and ALC), to evaluate whether Ma2 autoantibodies in the blood stream become a general biomarker for NETs. In total, 124 blood samples of SI-NET patients at different stages of disease were included in the study. The novel Ma2 autoantibody ELISA showed high sensitivity, specificity and accuracy with ROC curve analysis underlying an area between 0.734 and 0.816. Ma2 autoantibodies in the blood from SI-NET patients were verified by western blot and sequential immunoprecipitation. Serum antibodies of patients stain Ma2 in the tumor tissue and neurons. We observed that SI-NET patients expressing Ma2 autoantibody levels below the cutoff had a longer progression and recurrence-free survival compared to those with higher titer. We also detected higher levels of Ma2 autoantibodies in blood samples from TLC and ALC patients than from healthy controls, as previously shown in small cell lung carcinoma samples. Conclusion: Here we show that high Ma2 autoantibody titer in the blood of SI-NET patients is a sensitive and specific biomarker, superior to chromogranin A (CgA) for the risk of recurrence after radical operation of these tumors. [ABSTRACT FROM AUTHOR]

Summary: Objective: Large cell neuroendocrine carcinoma of the lung are considered aggressive. However, reported prognoses are heterogeneous and the optimum treatment remains undefined. We retrospectively evaluated outcomes in a series of patients with a pathological diagnosis of large cell neuroendocrine lung carcinoma, who underwent lung resection. We also assessed the utility of chemotherapy in a small subgroup. Patients and methods: The clinical records of 144 consecutive patients were reviewed in a multicenter study. Survival times, assessed from the day of surgery until death or most recent follow-up, were estimated by the Kaplan–Meier method, and compared by the log rank test. Results: There were 117 men and 27 women of median age 63 years. Twelve wedge resections, 3 segmentectomies, 95 lobectomies, 7 bilobectomies and 24 pneumonectomies were performed. Induction chemotherapy was given in 21 and postoperative chemotherapy in 24. Pathologically, 73 (50%) were stage I, 29 (20%) stage II, 40 (28%) stage III and 2 stage IV. Postoperative mortality was 2.8% and morbidity 26%. Overall 5-year survival was 42.5%: 52% for stage I, 59% for stage II and 20% for stage III (p =0.001 log-rank test on Kaplan–Meier curves). A trend to better outcome was associated with preoperative or postoperative chemotherapy in stage I disease (p =0.077) compared to no chemotherapy. The response rate to induction chemotherapy was 80% in the 15 patients with data available. Conclusion: large cell neuroendocrine carcinoma of the lung are confirmed as aggressive but are also chemosensitive. Our experience suggests that chemotherapy may improve prognosis in stage I disease. [Copyright &y& Elsevier]