Molecular characterization of diffuse large B-cell lymphomas associated with hepatitis C virus infection.

Hepatitis C virus (HCV)-associated diffuse large B-cell lymphoma (DLBCL) displays peculiar clinicopathological characteristics, but its molecular landscape is not fully elucidated. In this study, we investigated the clinicopathological and molecular features of 54 patients with HCV-associated DLBCL. The median age was 71 years. An underlying marginal zone lymphoma component was detected in 14.8% of cases. FISH analysis showed rearrangements involving BCL6 in 50.9% of cases, MYC in 11.3% and BCL2 in 3.7%. Lymph2Cx-based assay was successful in 38 cases, recognizing 16 cases (42.1%) as ABC and 16 cases as GCB subtypes, while six resulted unclassified. ABC cases exhibited a higher lymphoma-related mortality (LRM). Next-generation sequencing analysis showed mutations in 158/184 evaluated genes. The most frequently mutated genes were KMT2D (42.6%), SETD1B (33.3%), RERE (29.4%), FAS and PIM1 (27.8%) and TBL1XR1 (25.9%). A mutation in the NOTCH pathway was detected in 25.9% of cases and was associated with worst LRM. Cluster analysis by LymphGen classified 29/54 cases within definite groups, including BN2 in 14 (48.2%), ST2 in seven (24.2%) and MCD and EZB in four each (13.8%). Overall, these results indicate a preferential marginal zone origin for a consistent subgroup of HCV-associated DLBCL cases and suggest potential implications for molecularly targeted therapies.

An in-silico analysis reveals further evidence of an aggressive subset of lung carcinoids sharing molecular features of high-grade neuroendocrine neoplasms.

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.

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.

Preoperative systemic inflammatory markers as prognostic factors in differentiated thyroid cancer: a systematic review and meta-analysis.

BACKGROUND: Inflammation has been associated with tumor development and circulating inflammatory biomarkers have been proposed as possible predictors of recurrence of several solid tumors. However, the role of inflammation markers in differentiated thyroid carcinoma (DTC) is still uncertain. OBJECTIVE: This meta-analysis aimed to assess the prognostic value of neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) in patients with DTC. METHODS: Studies investigating the association between survival and preoperative circulating inflammatory markers in DTC patients were included. The primary outcome was disease-free survival (DFS). Cumulative logarithms of the hazard ratio (log-HRs) with 95% CI were calculated through the inverse variance method using a random-effects model. RESULTS: A total of 7599 patients with a mean age of 48.89 (95% CI 44.16-53.63) were included. The estimated pooled log-HRs for DFS were 0.07 for NLR (95% CI -0.12-0.26; p = 0.43), -0.58 for LMR (95% CI -1.21-0.05; p = 0.06), and 0.01 (95% CI 0-0.01; p = 0.21) for PLR. CONCLUSIONS: Our meta-analysis showed no association between NLR, PLR, LMR and DFS in DTC; however, more prospective data are needed to better define the association between inflammatory status and prognosis of DTC.

T-Cells Subsets in Castleman Disease: Analysis of 28 Cases Including Unicentric, Multicentric and HHV8-Related Clinical Forms.

Castleman disease (CD) is a rare lymphoproliferative disorder that includes various clinico-pathological subtypes. According to clinical course, CD is divided into unicentric CD (UCD) and multicentric CD (MCD). MCD is further distinguished based on the etiological driver in herpes virus-8-related MCD (that can occur in the setting of HIV); in MCD associated with POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes); and idiopathic MCD (iMCD). The latter can also be divided in iMCD-TAFRO (thrombocytopenia, anasarca, fever, myelofibrosis, organomegaly) and iMCD not otherwise specified. To date, CD pathogenesis is still uncertain, but CD may represent the histological and clinical result of heterogeneous pathomechanisms. Transcriptome investigations in CD lymph nodes have documented the expression and up-regulation of different cytokines; furthermore, few recent studies have shown alterations of different T-cell subsets in CD patients, suggesting a possible role of the nodal microenvironment in CD development. On this basis, our study aimed to investigate the distribution of T-cell subsets in the clinico-pathological spectrum of CD. We evaluated the CD4/CD8 ratio and the number of T-regulatory (T-reg) FOXP3+ cells in 28 CD cases. In total, 32% of cases showed a decreased CD4/CD8 ratio due to increased CD8+ T-cells, including both UCD, iMCD, and HHV8+ MCD cases. The T-reg subset analysis revealed a statistically significant (p < 0.0001) lower mean number of FOXP3+ T-reg cells in CD cases when compared with non-specific reactive lymph nodes. We did not find statistically significant differences in T-reg numbers between the different CD subtypes. These findings may suggest that alterations in T-cell subpopulations that can lead to disruption of immune system control may contribute to the numerous changes in different cellular compartments that characterize CD.

Pituitary neuroendocrine tumors: a model for neuroendocrine tumor classification.

The classification of adenohypophysial neoplasms as "pituitary neuroendocrine tumors" (PitNETs) was proposed in 2017 to reflect their characteristics as epithelial neuroendocrine neoplasms with a spectrum of clinical behaviors ranging from small indolent lesions to large, locally invasive, unresectable tumors. Tumor growth and hormone hypersecretion cause significant morbidity and mortality in a subset of patients. The proposal was endorsed by a WHO working group that sought to provide a unified approach to neuroendocrine neoplasia in all body sites. We review the features that are characteristic of neuroendocrine cells, the epidemiology and prognosis of these tumors, as well as further refinements in terms used for other pituitary tumors to ensure consistency with the WHO framework. The intense study of PitNETs has provided information about the importance of cellular differentiation in tumor prognosis as a model for neuroendocrine tumors in different locations.

Classification of neuroendocrine neoplasms: lights and shadows.

Neuroendocrine neoplasms (NENs) are a heterogeneous group of neoplastic proliferations showing different morphological features, immunophenotype, molecular background, clinical presentation, and outcome. They can virtually originate in every organ of the human body and their classification is not uniform among different sites. Indeed, as they have historically been classified according to the organ in which they primarily arise, the different nomenclature that has resulted have created some confusion among pathologists and clinicians. Although a uniform terminology to classify neuroendocrine neoplasms arising in different systems has recently been proposed by WHO/IARC, some issues remain unsolved or need to be clarified. In this review, we discuss the lights and shadows of the current WHO classifications used to define and characterize NENs of the pituitary gland, lung, breast and those of the head and neck region, and digestive and urogenital systems.

Pituitary metastases from neuroendocrine neoplasms: case report and narrative review.

PURPOSE: Pituitary metastases (PM) are uncommon findings and are mainly derived from breast and lung cancers. No extensive review of PM from neuroendocrine neoplasms (NENs) is on record. Here we describe a clinical case of PM from pancreatic NEN and review the clinical features of PM from NENs reported in the literature. METHODS: A case of PM from a pancreatic NEN followed at our institution is described. We also reviewed the 43 cases of PM from NENs reported in the literature. RESULTS: A 59-year old female patient, previously submitted to duodeno-cephalo-pancreasectomy for a well-differentiated pancreatic NEN, with known hepatic metastases, underwent a 68 Ga-DOTATOC PET/CT that revealed an uptake in the pituitary gland. A subsequent MRI displayed a pituitary lesion, with suprasellar extension. After a hormonal and genetic diagnostic workup that excluded the diagnosis of MEN 1, the worsening of headache and visual impairment and the growth of the lesion lead to its surgical removal. A pituitary localization of the pancreatic NEN was identified. Regarding the published cases of PM from NENs, the most common tumour type was small cell lung cancer (SCLC), accounting for nearly half of the cases, followed by bronchial and pancreatic well differentiated NENs. The most frequent symptom was a variable degree of visual impairment, while headache was reported in half of the cases. Partial or total anterior hypopituitarism was present in approximately three quarters of the cases, while diabetes insipidus was less common. The most frequent treatment for PM was surgical resection, followed by radiotherapy and chemotherapy. The clinical outcome was in line with previous reports of PM from solid tumours, with a median survival of 14 months. Surgery of PM was associated with prolonged survival. CONCLUSIONS: PM from NENs have clinical features similar to metastases derived from other solid tumours, albeit the involvement of the anterior pituitary seems more frequent; a thorough pituitary hormonal evaluation is mandatory, after focused radiological studies, particularly if a surgical approach is considered. The optimal management of PM remains disputed and seems mainly driven by the aggressiveness of the primary tumour and the presence of symptoms. In well-differentiated NENs, particularly in the case of symptomatic PM, surgical removal may be a reasonable approach.

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.

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.

Angiosarcoma and anaplastic carcinoma of the thyroid are two distinct entities: a morphologic, immunohistochemical, and genetic study.

Angiosarcoma and anaplastic carcinoma are the most lethal neoplasms of the thyroid worldwide and share some similarities, which have led to a longstanding controversy on their etiopathological relationship. Thyroid angiosarcomas are characterized by vessel formation and an immunophenotype common to endothelial cells, while anaplastic carcinomas are partially or wholly composed of mesenchymal-like cells that have lost the morphologic and functional features of normal thyroid follicular cells. To investigate whether angiosarcomas represent the endothelial extreme of the differentiation spectrum of carcinomas or they are bona fide vascular neoplasms, we studied the clinico-morphologic and genetic characteristics of a series of 10 angiosarcomas and 22 anaplastic carcinomas. Immunohistochemically, among the endothelial markers, CD31 and ERG were the most consistently expressed in angiosarcomas. Among the markers of thyroid origin, PAX8 was the most reliable in anaplastic carcinomas, while TTF-1 reactivity was found in only 5% of anaplastic carcinomas and thyroglobulin was always negative. Pankeratin reacted with most angiosarcomas and anaplastic carcinomas and is therefore not useful in the differential diagnosis. Interestingly a mutated pattern of p53 immunostaining prompted a diagnosis of anaplastic carcinoma. To compare the genetic profile, we used the NGS approach to sequence hotspot regions within a panel of 57 genes. As a result, only a few mutations were found in angiosarcomas and all of them were single events (no TP53 or TERT mutation). On the other hand, anaplastic carcinomas were characterized by a higher number of mutations, and TP53 and TERT promoter mutations were the most frequent genetic alterations. The lack in angiosarcomas of the common mutations identified in anaplastic carcinomas supports a different genetic origin and strongly suggests that, in spite of a shared sarcomatous morphology and a similar clinical aggressiveness, angiosarcomas and anaplastic carcinomas rely on a completely different set of genetic alterations during their evolution.

PD-1 (PDCD1) promoter methylation in Merkel cell carcinoma: prognostic relevance and relationship with clinico-pathological parameters.

Merkel cell carcinoma is an aggressive neuroendocrine skin tumor, for which several non-conclusive prognostic factors of adverse clinical behavior have been reported. As promoter methylation of the immune checkpoint receptor CD279/PD-1/PDCD1(mPDCD1) has been shown to be a prognostic factor in different cancers, we investigated its role in Merkel cell carcinoma. mPDCD1was assessed retrospectively in a cohort of 69 Merkel cell carcinoma patients from the University of Bologna, University of Turin and University of Insubria. Kaplan-Meier curves and log-rank tests were calculated for all variables. To assess the influence of mPDCD1, the Cox proportional hazards model and different Royston-Parmar models were evaluated. High PDCD1 methylation (mPDCD1high) was associated with a higher overall mortality at both the univariate analysis (log rank test: χ2 = 5.17, p = 0.023; permutation test: p = 0.023) and the multivariate analysis (HR = 2.111, p = 0.042). The other variables associated with a higher overall mortality at the multivariate analysis were clinical stage III-IV (HR = 2.357, p = 0.008), size > 2 cm (HR = 2.248, p = 0.031) and Merkel cell polyomavirus (HR = 0.397, p = 0.015). Further, mPDCD1high was strongly associated with older age (81 vs 76 years, p = 0.042), absence of immune cells (92.6%, p < 0.001), no expression of PD-L1 by immune cells (70.4%, p = 0.041) and by both immune and tumor cells (70.4%, p = 0.001). mPDCD1 is a valid prognostic parameter in patients affected by Merkel cell carcinoma. In addition, it could provide an estimate of the global PD-1/PD-L1 expression with potentially relevant implications from a therapeutic point of view.

Clinical and molecular characteristics of lymphoplasmacytic lymphoma not associated with an IgM monoclonal protein: A multicentric study of the Rete Ematologica Lombarda (REL) network.

Lymphoplasmacytic lymphoma (LPL) is usually associated with a serum IgM paraprotein, corresponding to Waldenström's Macroglobulinemia (WM). Cases presenting with IgG or IgA, or without a monoclonal protein are extremely rare. We analyzed clinical characteristics, frontline treatment, and the outcome of 45 patients with non-IgM LPL, and compared them with a control group of WM patients. The median age was similar, with significantly higher prevalence of females in non-IgM LPL, than in WM patients (60% vs 39%, P = .016). Patients with non-IgM LPL more frequently presented with lymphadenopathies (53% vs 15%, P < .001), splenomegaly (22% vs 8%, P = .015) or extranodal involvement (20% vs 8%, P = .05). In non-IgM LPL a serum monoclonal protein and bone marrow infiltration were less common than in WM patients (69% and 84% of cases respectively, P < .001 for both comparisons). The MYD88 (L265P) mutation was found in 8/19 patients using allele-specific polymerase chain reaction. A CXCR4 mutation was found in 4/17 cases using Sanger. In 16 patients we performed targeted next-generation sequencing of genes MYD88, CXCR4, ARID1-A, KMT2D, NOTCH2, TP53, PRDM1, CD79B, TRAF3, MYBBP1A, TNFAIP3. Seven patients (44%) had a MYD88 mutation (S219C in one), four (25%) a CXCR4 mutation, three (19%) a KMT2D mutation, one (6%) a TP53 mutation and one (6%) a TRAF3 mutation. With a median follow-up of 55.7 months, 36 non-IgM LPL patients (80%) were treated. Non-IgM LPL patients received more frequently anthracycline-containing regimens, as compared with WM patients, who mainly received alkylating-based therapies. Five-year overall survival (OS) was 84%, similar to that of WM patients.

Primary Extranodal Marginal Cell Lymphoma, MALT Type, of the Endometrium Arising in a Patient With Rheumatoid Arthritis: Report of a Case.

Primary marginal zone B-cell MALT-type lymphomas of the uterine corpus are exceedingly rare entities, with only 6 cases reported in the literature to date. We present the additional case of a 70-yr-old white woman who underwent a laparoscopic total hysterectomy with bilateral salpingo-oophorectomy for an asymptomatic ovarian cyst. At microscopic examination, endometrial samples showed a dense, nodular lymphocytic infiltrate, suggestive of a lymphoproliferative disorder. Morphology, immunohistochemistry, and molecular analysis supported the diagnosis of MALT-type lymphoma of the endometrium. Benign reactive conditions, such as endometritis and other small B-cell lymphomas were ruled out. Moreover, we investigated the pathogenesis of our case, focusing on Chlamydia trachomatis infection, chromosomal translocations affecting the NF-kB pathway, and discussing the role of autoimmunity in the development of MALT-type lymphomas.

Molecular Classification of Gastrointestinal and Pancreatic Neuroendocrine Neoplasms: Are We Ready for That?

In the last two decades, the increasing availability of technologies for molecular analyses has allowed an insight in the genomic alterations of neuroendocrine neoplasms (NEN) of the gastrointestinal tract and pancreas. This knowledge has confirmed, supported, and informed the pathological classification of NEN, clarifying the differences between neuroendocrine carcinomas (NEC) and neuroendocrine tumors (NET) and helping to define the G3 NET category. At the same time, the identification genomic alterations, in terms of gene mutation, structural abnormalities, and epigenetic changes differentially involved in the pathogenesis of NEC and NET has identified potential molecular targets for precision therapy. This review critically recapitulates the available molecular features of digestive NEC and NET, highlighting their correlates with pathological aspects and clinical characteristics of these neoplasms and revising their role as predictive biomarkers for targeted therapy. In this context, the feasibility and applicability of a molecular classification of gastrointestinal and pancreatic NEN will be explored.

PD-L1 expression, tumor-infiltrating lymphocytes, and mismatch repair proteins status in digestive neuroendocrine neoplasms: exploring their potential role as theragnostic and prognostic biomarkers.

Theragnostic biomarkers are still needed to select patients with digestive neuroendocrine neoplasms (NENs) for an optimal management. The PD-1/PD-L1 pathway plays a pivotal role in T cells activation and host immune response to cancer and PD-L1 expression in tumor and/or immune cells is used to identify patients who would benefit of treatment with immune checkpoint inhibitors. However, its role as a biomarker is still unclear in digestive NENs. We investigated PD-L1 expression in 68 well-characterized digestive NENs (32 NETs, 32 NECs and 4 MiNENs) and TPS and CPS scores were calculated. In addition, tumor infiltrating T-lymphocytes and mismatch repair protein expression (MMR) were evaluated. All results were correlated with clinicopathological features. PD-L1 expression was higher in NECs than in NETs: TPS > 1% and/or CPS > 1 were observed in 16% of NETs, 68.8% of NECs and 50% of MiNENs (p: 0.05). The mean TPS score in positive cases was 6.3% in NETs, 16.2% in NECs and 5% in MiNENs. The CPS score was 4.8 in NETs, 8.1 in NECs and 6 in MiNENs. MMR-deficient neoplasms were more frequently observed in NECs than in NETs (p: < 0.05) as well as intra-tumor immune infiltration (p: 0.00001). No correlation between PD-L1 expression and survival or other clinicopathological parameters was observed. Our results suggest that treatment with immune checkpoint inhibitors may have a potential role only in selected cases, mainly in NECs and MiNENs.