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William Vermi - One of the best experts on this subject based on the ideXlab platform.

  • Neoplasms derived from plasmacytoid dendritic cells
    Modern Pathology, 2016
    Co-Authors: Fabio Facchetti, Marta Cigognetti, Simona Fisogni, Giuseppe Rossi, Silvia Lonardi, William Vermi

    Plasmacytoid dendritic cell Neoplasms manifest in two clinically and pathologically distinct forms. The first variant is represented by nodular aggregates of clonally expanded plasmacytoid dendritic cells found in lymph nodes, skin, and bone marrow (‘Mature plasmacytoid dendritic cells proliferation associated with myeloid Neoplasms’). This entity is rare, although likely underestimated in incidence, and affects predominantly males. Almost invariably, it is associated with a myeloid Neoplasm such as chronic myelomonocytic leukemia or other myeloid proliferations with monocytic differentiation. The concurrent myeloid Neoplasm dominates the clinical pictures and guides treatment. The prognosis is usually dismal, but reflects the evolution of the associated myeloid leukemia rather than progressive expansion of plasmacytoid dendritic cells. A second form of plasmacytoid dendritic cells tumor has been recently reported and described as ‘blastic plasmacytoid dendritic cell Neoplasm’ . In this tumor, which is characterized by a distinctive cutaneous and bone marrow tropism, proliferating cells derive from immediate CD4^+CD56^+ precursors of plasmacytoid dendritic cells. The diagnosis of this form can be easily accomplished by immunohistochemistry, using a panel of plasmacytoid dendritic cells markers. The clinical course of blastic plasmacytoid dendritic cell Neoplasm is characterized by a rapid progression to systemic disease via hematogenous dissemination. The genomic landscape of this entity is currently under intense investigation. Recurrent somatic mutations have been uncovered in different genes, a finding that may open important perspectives for precision medicine also for this rare, but highly aggressive leukemia.

Attilio Orazi - One of the best experts on this subject based on the ideXlab platform.

  • Hematopoietic Neoplasms with 9p24/JAK2 rearrangement: a multicenter study
    Modern Pathology, 2019
    Co-Authors: Guilin Tang, John Kennedy Sydney Sir Philip, Olga Weinberg, Sam Sadigh, Jonathan I. Lake, Elizabeth M. Margolskee, Carlos Bueso-ramos C, Roberto N. Miranda, Heesun J Rogers, Attilio Orazi

    The purpose of this study is to examine hematopoietic Neoplasms with 9p24/ JAK2 rearrangement including Neoplasms associated with t(8;9)(p22;p24)/ PCM1-JAK2 fusion Neoplasm as well as cases with translocations involving 9p24/ JAK2 and other partner genes. From seven large medical centers, we identified ten patients with t(8;9)(p22;p24) / PCM1-JAK2 and 3 with t(9p24;v)/ JAK2 at diagnosis. Majority of the cases showed myeloproliferative Neoplasm (MPN) associated features ( n  = 7) characterized by variable degrees of eosinophilia, myelofibrosis, frequent proliferations of early erythroblasts in bone marrow and extramedullary sites, and infrequent/absent somatic mutations. Other less common presentations included myelodysplastic syndromes (MDS) or MDS/MPN (one each). Four patients presented with B-lymphoblastic leukemia (B-ALL), and of them, two patients with t(8;9)(p22;p24.1) were proven to be B-lymphoblastic crisis of MPN; and the other two cases with t(9p24;v) both were de novo B-ALL, BCR-ABL1 -like (Ph-like). We show that the hematopoietic Neoplasms with 9p24/ JAK2 rearrangement are extremely rare, and most of them are associated with t(8;9)(p22;p24)/ PCM1-JAK2 , a recent provisional World Health Organization entity under “myeloid/lymphoid Neoplasm with a specific gene rearrangement”. Cases of t(8;9)(p22;p24)/ PCM1-JAK2 , though heterogeneous, do exhibit some common clinicopathological characteristic features. Cases with t(9p24;v)/ JAK2 are extremely rare; while such cases with a MPN presentation may resemble t(8;9)(p22;p24.1)/ PCM1-JAK2 , B-ALL cases presenting de novo B-ALL might belong to Ph-like B-ALL.

  • Bone marrow morphology and disease progression in congenital thrombocytopenia: a detailed clinicopathologic and genetic study of eight cases
    Modern Pathology, 2017
    Co-Authors: Hamilton C Tsang, Attilio Orazi, James B Bussel, Susan Mathew, Allison A Imahiyerobo, Julia T Geyer

    Patients with congenital thrombocytopenia have an increased risk of developing myeloid Neoplasms. In these cases, the morphologic distinction between disease at baseline and at progression is challenging. This report analyzes clinicopathologic features of congenital thrombocytopenia with long-term follow-up at one referral center. Records from the last 20 years were searched for cases of congenital thrombocytopenia with bone marrow biopsies and peripheral blood smears. The clinical, morphologic, immunophenotypic, and molecular features were analyzed. Six adult and two pediatric patients were identified (six male, two female). Age range at first biopsy was 1–47 (median, 31) years. Underlying diseases included thrombocytopenia-absent radius syndrome, congenital thrombocytopenia with radial–ulnar synostosis, MYH9 -related disorder, shortened telomere syndrome, congenital thrombocytopenia with ANKRD26 mutation, and familial platelet disorder with predisposition to acute myeloid leukemia. Four patients had myelodysplastic/myeloproliferative Neoplasm-like marrow changes such as hypercellularity, increased myeloid to erythroid ratio, numerous micromegakaryocytes (highlighted by CD42b), and marrow fibrosis. Two patients had marrow hypoplasia and two had unremarkable marrow morphology. Three patients—all in the myelodysplastic/myeloproliferative Neoplasm-like group—developed disease progression characterized by erythroid and myeloid dysplasia, elevated bone marrow blasts, and new cytogenetic abnormalities. Unlike non-familial myeloid Neoplasms, congenital thrombocytopenia patients in the myelodysplastic/myeloproliferative Neoplasm-like group had a long and indolent clinical course (average age at disease progression, 47 years). In summary, three distinct morphologic types of congenital thrombocytopenia were identified: a hyperplastic myelodysplastic/myeloproliferative Neoplasm-like group, a hypoplastic bone marrow failure-like group, and a group with relatively normal marrow morphology. Emergence of cytogenetic abnormalities and dysplasia in non-megakaryocyte lineages correlated with disease progression.

Andrew L Folpe - One of the best experts on this subject based on the ideXlab platform.

  • cd1a immunopositivity in perivascular epithelioid cell Neoplasms true expression or technical artifact a streptavidin biotin and polymer based detection system immunohistochemical study of perivascular epithelioid cell Neoplasms and their morphologic
    Human Pathology, 2011
    Co-Authors: William A Ahrens, Andrew L Folpe

    Summary Perivascular epithelioid cell Neoplasms comprise a family of rare Neoplasms composed of morphologically distinctive perivascular epithelioid cells exhibiting a “myomelanocytic” immunophenotype. The distinction of perivascular epithelioid cell Neoplasms from other tumors with melanocytic and smooth muscle differentiation can be difficult. A recent study has suggested that perivascular epithelioid cell Neoplasms routinely express CD1a, a Langerhans cell–associated transmembrane glycoprotein involved in antigen presentation and that expression of this marker may be helpful in the distinction of perivascular epithelioid cell Neoplasms from various mimics. We evaluated a series of perivascular epithelioid cell Neoplasms and potential mimics for CD1a expression. A total of 54 cases (27 perivascular epithelioid cell Neoplasms, 11 leiomyosarcomas, 10 melanomas, 6 clear cell sarcomas) were evaluated in 2 laboratories (Mayo Clinic Rochester: 31 cases, Carolinas Medical Center: 23 cases). Selected positive cases were retested at Carolinas Medical Center (11 cases) and Mayo Clinic Rochester (10 cases). Mayo Clinic Rochester methods were as follows: MTB1 clone (1:20, Novocastra, Newcastle-upon-Tyne, UK), heat-induced epitope retrieval in EDTA (pH 8.0), and Dako Advance detection system (Dako Corp, Carpinteria, CA) with background-reducing diluent. Carolinas Medical Center methods were as follows: MTB1 clone (1:30; CellMarque, Rocklin, CA), heat-induced epitope retrieval in Medium Cell Conditioner #1 (pH 8.0-9.0), and streptavidin-biotin detection system with diaminobenzidine chromogen, with and without biotin blocking. Scores were as follows: 1+, 5% to 25%; 2+, 26% to 50%; and 3+, more than 51%. Langerhans cells served as a positive internal control in all tested cases. All Mayo Clinic Rochester cases were negative. Sixteen Carolinas Medical Center perivascular epithelioid cell Neoplasms (14 renal angiomyolipomas, 1 soft tissue perivascular epithelioid cell Neoplasm, 1 pulmonary clear cell “sugar” tumor) showed CD1a immunopositivity (1+: 7 cases; 2+: 7 cases; 3+: 2 cases) when tested without biotin blocking, 11 of these cases were retested with biotin blocking and were negative. All non–perivascular epithelioid cell Neoplasms were negative. All positive perivascular epithelioid cell Neoplasms showed cytoplasmic staining only, without membranous staining. Ten Carolinas Medical Center positive perivascular epithelioid cell Neoplasms were negative when retested a Mayo Clinic Rochester, using a polymer-based detection system. We conclude that perivascular epithelioid cell Neoplasms do not truly express CD1a in a biologically plausible membranous pattern, but may instead show aberrant cytoplasmic immunopositivity in some laboratories. Close inspection of published photomicrographs of previously reported CD1a-positive perivascular epithelioid cell Neoplasms shows an identical pattern of cytoplasmic positivity, likely reflecting abundant endogenous biotin within perivascular epithelioid cell Neoplasm cells. We do not believe that there is a role for CD1a immunohistochemistry in the differential diagnosis of perivascular epithelioid cell Neoplasms.

Michael G Sarr - One of the best experts on this subject based on the ideXlab platform.

  • Primary pancreatic cystic Neoplasms of the pancreas revisited. Part IV: rare cystic Neoplasms.
    Surgical Oncology-oxford, 2011
    Co-Authors: George H. Sakorafas, Vasileios Smyrniotis, Kaye M. Reid-lombardo, Michael G Sarr

    Abstract Primary pancreatic cystic Neoplasms are being recognized with increasing frequency due to modern imaging techniques. In addition to the more common cystic Neoplasms—serous cystadenoma, primary mucinous cystic Neoplasm, and intraductal papillary mucinous Neoplasm—there are many other less common Neoplasms that appear as cystic lesions. These cystic Neoplasms include solid pseudopapillary Neoplasm of the pancreas (the most common rare cystic Neoplasm), cystic neuroendocrine Neoplasm, cystic degeneration of otherwise solid Neoplasms, and then the exceedingly rare cystic acinar cell Neoplasm, intraductal tubular Neoplasm, angiomatous Neoplasm, lymphoepithelial cysts (not true Neoplasms), and few others of mesenchymal origin. While quite rare, the pancreatic surgeon should at the least consider these unusual Neoplasms in the differential diagnosis of potentially benign or malignant cystic lesions of the pancreas. Moreover, each of these unusual Neoplasms has their own natural history/tumor biology and may require a different level of operative aggressiveness to obtain the optimal outcome.

  • Primary pancreatic cystic Neoplasms revisited. Part I: serous cystic Neoplasms.
    Surgical Oncology-oxford, 2011
    Co-Authors: George H. Sakorafas, Vasileios Smyrniotis, Kaye M. Reid-lombardo, Michael G Sarr

    Abstract Primary pancreatic cystic Neoplasms have been recognized increasingly during the two recent decades and include mainly serous cystic Neoplasms, mucinous cystic Neoplasms, and intraductal papillary mucinous Neoplasms. Serous cystic Neoplasms represent about 30% of all cystic Neoplasms of the pancreas and are characterized by their microcystic appearance (on imaging, macroscopically, and microscopically) and their benign biologic behavior. Modern diagnostic methodology allows the preoperative diagnosis with an acceptable accuracy. Currently, indications for resection of serous cystic Neoplasms of the pancreas include the presence of symptoms, size > 4 cm (because these ‘large' Neoplasms have a more rapid growth rate and probably will soon become symptomatic), and any uncertainty about the diagnosis of a serous versus a mucinous cystic Neoplasm. Resection should also be considered for lesions in the body/tail of the pancreas. Conservative treatment is a reasonable option in selected patients (for example in the presence of small, asymptomatic lesions in the pancreatic head, especially in the frail or elderly patient).

  • pancreatic mucinous cystic Neoplasm defined by ovarian stroma demographics clinical features and prevalence of cancer
    Clinical Gastroenterology and Hepatology, 2004
    Co-Authors: Raghuram P Reddy, Thomas C Smyrk, Mauricio Zapiach, Michael J Levy, Randall K Pearson, Jonathan E Clain, Michael B Farnell, Michael G Sarr, Suresh T Chari

    Background & Aims: Pancreatic mucin-producing cystic Neoplasms are classified into 2 distinct entities: mucinous cystic Neoplasm (MCN) and intraductal papillary mucinous Neoplasm (IPMN). In previous studies, MCN often has been defined loosely and has not always been distinguished clearly from IPMN. Our aims were to determine the demographics, clinical features, and prevalence of invasive cancer in MCN defined by the presence of characteristic ovarian stroma. Methods: By using the presence of ovarian stroma as a requisite criterion for diagnosis of MCN, a single pathologist, unaware of clinical information, identified 56 MCNs from 243 mucin-producing Neoplasms resected at Mayo Clinic between 1986 and 2003. Medical records of the MCN patients were reviewed to obtain clinical and demographic data. Results: Patients with MCN were almost exclusively (98%) women; we identified 1 man with a Neoplasm containing ovarian stroma. The mean (±SD) age at resection was 48 ± 15 years (84% Conclusions MCN defined by ovarian stroma has a distinct demographic and clinical profile and a low prevalence of invasive cancer. These observations suggest that ovarian stroma should be used as the defining criterion for diagnosing MCN.

  • Cystic Neoplasms of the pancreas: benign to malignant epithelial Neoplasms.
    Surgical Clinics of North America, 2001
    Co-Authors: Michael G Sarr, Michael L. Kendrick, David M. Nagorney, Geoffrey B. Thompson, David R. Farley, Michael B Farnell

    Although all cystic Neoplasms of the pancreas have relatively similar characteristics on modern imaging modalities, the cells of origin and their biologic aggressiveness are quite different and mandate a selective management approach. This spectrum of cystic disorders encompasses biologically diverse and questionably related diseases, which include the following four broad categories: 1Serous cystadenomas are composed of grapelike collections of predominantly small ( 13 This category used to be referred to as microcystic Neoplasm; however, this term is inappropriate and should be deleted from the current nomenclature. 2Mucinous cystic Neoplasms (formerly known inappropriately as macrocystic Neoplasms) represent a continuum ranging from (a) clinically and pathologically benign mucinous cystadenomas; (b) histologically dysplastic, aggressive-appearing, yet non-invasive proliferative mucinous cystic Neoplasms that, if fully resected, do not recur; 14,20 and, (c) rare malignant (tissue invasion) mucinous cystadenocarcinomas, which approach the biologic aggressiveness of typical ductal cancer of the pancreas. These mucinous cystic Neoplasms are composed of mucin-containing cells that may express varying degrees of atypia, dysplasia, carcinoma in situ, and tissue invasion within the same tumor. 3Intraductal papillary mucinous tumor (IPMT) represents a newly recognized entity that also has been referred to most commonly as mucinous ductal ectasia. IPMT represents a spectrum of neoplastic processes composed of mucinous cells lining the main pancreatic duct or secondary pancreatic ducts. 10 Significant controversy exists over whether IPMT represents a novel Neoplasm arising from a different epithelium or a variant of mucinous cystic Neoplasm involving the main pancreatic duct(s). Nevertheless, all agree that IPMT is a premalignant disorder that is recognized with increasing frequency. No reports of this disease existed before 1980. Whether IPMT truly represents a new entity (induced by environmental factors or a new mutation) or was previously overlooked and miscategorized as a ductal adenocarcinoma of the pancreas with mucinous differentiation is unclear; however, many of the clinical and imaging characteristics are so unique that it is hard to believe that it was merely overlooked in the past. 4Unusual cystic Neoplasms include the extremely rare cystic islet cell tumors (functional and nonfunctional), acinar cell cystadenocarcinomas, cystic choriocarcinomas, cystic teratomas, and cystic lymphangiomatous Neoplasms. 21 These are all so unusual that they are not mentioned further in this article.

Endi Wang - One of the best experts on this subject based on the ideXlab platform.

  • blastic plasmacytoid dendritic cell Neoplasm a clinicopathologic review
    Archives of Pathology & Laboratory Medicine, 2014
    Co-Authors: Endi Wang

    : Blastic plasmacytoid dendritic cell Neoplasm is a rare entity grouped with the acute myeloid leukemia-related precursor Neoplasms in the 2008 World Health Organization classification. It was previously postulated to originate from natural killer cells, T cells, or monocytes but is now believed to arise from the plasmacytoid dendritic cell. The pathogenesis of blastic plasmacytoid dendritic cell Neoplasm is not well understood, although the Neoplasm demonstrates frequent deletion of tumor suppressor genes, including RB1, CDKN1B, CDKN2A, and TP53. Blastic plasmacytoid dendritic cell Neoplasm is a clinically aggressive tumor that often initially presents as cutaneous lesions and subsequently progresses to bone marrow involvement and leukemic dissemination. It is characterized by enhanced expression of CD56, CD4, and CD123, which can be detected by flow cytometry/immunohistochemistry. The differential diagnoses include myeloid sarcoma/acute myeloid leukemia, T-cell lymphoblastic leukemia/lymphoma, NK-cell lymphoma/leukemia, and some mature T-cell lymphomas/leukemias. Patients usually respond to initial chemotherapy but often relapse. Stem cell transplant may improve survival.