Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0079731 (B-cell lymphoma)
 16,671 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Twenty-four cases of cutaneous lymphomas were classified as T-cell (18 cases), B-cell (three cases), and true histiocytic (three cases), on the basis of the histochemical and immunohistochemical characteristics. Important differences in clinical and histopathologic features exist among these three types: skin lesions of T-cell lymphoma are usually chronic, pruritic, and sometimes ulcerative; those of B-cell lymphoma are nonpruritic and nonulcerative; lesions of true histiocytic lymphoma are often pruritic and ulcerative. All three patients with true histiocytic lymphoma died within six months of diagnosis. Two of the three patients with B-cell lymphoma died within two years of diagnosis. Only two of the 18 patients with T-cell lymphoma died, one after 12 years and the other after six years. Histologically, B-cell lymphoma shows a grenz zone in the upper dermis and absence of epidermal involvement; both T-cell and true histiocytic lymphomas show epidermal infiltration and absence of a grenz zone. True histiocytic lymphoma can appear similar to T-cell lymphoma clinically and histologically by routine examination, but histiocytic lymphoma has a much worse prognosis. Histochemical and immunohistochemical studies are very helpful in the differential diagnosis.
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PMID:Cutaneous lymphomas: correlation of histochemical and immunohistochemical characteristics and clinicopathologic features. 660 May 78

True histiocytic lymphoma (THL) and malignant histiocytosis (MH) have been defined by clinical and histologic findings and enzyme histochemistry. We reviewed cases previously diagnosed as cutaneous histiocytic lymphoma (HL) and MH with cutaneous lesions. These cases had been classified as "histiocytic" on the basis of previous enzyme histochemistry profiles of frozen tissue. Cutaneous tumor cells were reevaluated using a panel of immunohistochemical stains in formalin-fixed, paraffin-embedded tissue in correlation with histopathologic examination. The antibodies used in this study were directed against CD45 (leukocyte common antigen [LCA]), CD20 (L26) for B cells, CD3 and CD45RO (UCHL-1) for T cells, CD68 (KP-1) and lysozyme for histiocytes, as well as CD30 (BerH2) for Ki-1 positive cells. On re-evaluation, the seven cases originally classified as HL were reclassified as one case of THL with neoplastic cells positive for CD68 (KP-1) and lysozyme, two cases with immunohistochemical features of Ki-l lymphoma (including one of T-cell lineage), three cases of T-cell lymphoma, and one case of B-cell lymphoma, all associated with variable degrees of reactive histiocytosis. The four cases originally classified as MH were reclassified as two cases of MH and two cases of uncertain lineage. Although rare, histiocytic malignancies do exist. However, the diagnosis of histiocytic malignancy should be made only after careful correlation of atypical tumor cells in histopathologic sections and sections stained immunohistochemically. Erroneous classification of reactive histiocytes as neoplastic histiocytes using only enzyme histochemistry in frozen sections is a pitfall to be avoided.
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PMID:Cutaneous histiocytic malignancy. Immunohistochemical re-examination of cases previously diagnosed as cutaneous "histiocytic lymphoma" and "malignant histiocytosis". 832 Mar 54

True histiocytic lymphoma is considered a rare entity, and its diagnosis requires the concordance of morphological, immunophenotypic, and molecular findings. The association of malignant lymphoma with tumors in the monocyte-macrophage system has rarely been described. We present a case of mucosa-associated lymphoid tissue (MALT)-type low-grade B-cell lymphoma of the stomach, contiguous to a large tumoral mass that fulfills the morphological criteria (large cells with abundant pale cytoplasm and lobulated or kidney-shaped nuclei) and immunophenotypical features (human leukocyte antigen-DR locus, CD68, S-100, lysozyme immunoreactivity, and negative B- and T-cell markers) required for the diagnosis of histiocytic lymphoma. The patient remains in complete remission 18 months after surgery. The association of low grade-malignant lymphoma with tumors of monocyte-macrophage system cells is an exceedingly rare phenomenon. Whether these tumors are directly related or occur due to pure chance requires the identification of new cases and further study.
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PMID:True histiocytic lymphoma of the stomach associated with low-grade B-cell mucosa-associated lymphoid tissue (MALT)-type lymphoma. 889 46

To describe the contrast-enhanced ultrasonographic appearance of various focal, space-occupying renal lesions and determine its value in their detection and characterization. Following baseline B-mode sonography of 15 dogs and one cat with renal space-occupying lesion(s), contrast-enhanced sonography was performed. The resulting images were evaluated qualitatively using conspicuity and number of lesions, and enhancement patterns were assessed during early arterial and late corticomedullary phases. Renal lesions were malignant in the cat (renal cell carcinoma) and 10 dogs (four renal cell carcinoma, two histiocytic sarcoma, one B-cell lymphoma, two hemangiosarcoma metastasis, one ch emodectoma metastasis) and benign in five dogs (two abscesses, one traumatic hematoma, one idiopathic hematoma, one hemorrhagic/necrotic nodule). Substantial overlap was present regarding the baseline sonographic features of benign vs. malignant lesions. With contrast-enhanced sonography, all renal cell carcinomas were characterized by large tortuous arteries, sometimes enhancing slightly earlier than vessels in the surrounding normal kidney. During the late corticomedullary phase, renal cell carcinomas had intense homo- or heterogeneous, iso- or slightly hypoechoic enhancement, which decreased progressively. Compared with renal cell carcinoma, histiocytic sarcoma and lymphoma had smaller and less obvious arteries, and an earlier loss of enhancement during the late phase. All hemangiosarcoma metastases appeared as nonenhancing nodules during the early arterial and late corticomedullary phases of enhancement, and additional lesions were detected. Histiocytic sarcoma and benign lesions had increased conspicuity with baseline sonography. The descriptions provided herein will be valuable as more work is done to establish the role of contrast-enhanced sonography in the assessment of renal lesions.
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PMID:Contrast harmonic ultrasonographic appearance of focal space-occupying renal lesions. 2097 85

Histiocytic sarcoma (HS) is an extremely rare malignant neoplasm showing morphologic and immunophenotypic evidence of histiocytic differentiation. The vast majority of previously reported HSs are now generally recognized to be misdiagnosed examples of non-Hodgkin lymphomas, predominantly diffuse large B-cell lymphoma or anaplastic large cell lymphoma. The recognition of such tumors parallels the development and widespread use of immunohistochemical techniques, along with the development of molecular genetic methods to detect immunoglobulin (IG) or T-cell receptor (TCR) gene rearrangement. The 2001 World Health Organization (WHO) definition of HS requires the absence of clonal B/T-cell receptor gene rearrangements. However, the 2008 WHO classification no longer strictly requires the absence of clonal immunoglobulin heavy chain (IGH) or TCR gene rearrangement for the diagnosis of HS. Recent studies demonstrated that HSs that occur subsequent to or concurrent with B- or T-lymphoblastic lymphoma/leukemia or mature B-cell neoplasms generally show clonal IgH and/or TCR gene rearrangement. These findings suggest the possibility of transdifferentiation of the two otherwise morphologically and immunohistochemically distinctive neoplasms. In addition, a recent study suggested clonal IG gene rearrangements may be detected at a high frequency in sporadic HS, indicating that a large subset of sporadic HSs may inherit the B-lymphocyte genotype. These findings provide new insights into the pathogenesis of HS, although the etiology of HS is still unknown. HS is a diagnosis of exclusion. It is necessary to rule out other diseases that could be misdiagnosed as HS with extensive immunophenotypical analysis before diagnosing HS.
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PMID:Histiocytic sarcoma : an updated literature review based on the 2008 WHO classification. 2380 Nov 28

Histiocytic sarcoma (HS) is a rare malignant tumor, and in extraordinary circumstances it can be transdifferentiated from a low-grade B-cell lymphoma. In our report, a 62-year-old female was initially diagnosed with a low-grade follicular lymphoma, and 2 years later she presented with bilateral lung masses and lymphadenopathy. Fine needle aspiration (FNA) of the lung masses revealed solid nests of large pleomorphic epithelioid cells. By immunohistochemical studies, the tumor cells were positive for histiocytic markers (CD68 and CD163) and S100, supporting a diagnosis of HS with dendritic cell differentiation. Further fluorescence in situ hybridization (FISH) analyses detected IGH@/BCL2 rearrangement in both the previous follicular lymphoma and the current HS, which was highly suggestive of the clonal relationship between these two tumors. To the best of our knowledge, this is the first case of transformation of follicular lymphoma into HS diagnosed by FNA of lung masses.
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PMID:Fine needle aspiration cytology of histiocytic sarcoma with dendritic cell differentiation: a case of transdifferentiation from low-grade follicular lymphoma. 2599 73

Histiocytic sarcoma is rare and difficult to distinguish from histologic mimics such as myeloid sarcoma due to its relatively nonspecific immunoprofile. A subset of histiocytic sarcomas are clonally related to synchronous or metachronous follicular lymphomas. Interestingly, the histiocytic tumor component has been shown to harbor BCL2 gene translocations that are identical to those found in the lymphoma. We present one case of histiocytic sarcoma and initially occult follicular lymphoma in which detection of a BCL2 gene translocation helped support the diagnosis. We also provide follow-up regarding a previously published case of histiocytic sarcoma with IGH/BCL2 fusion gene in which the patient subsequently developed follicular lymphoma and, later, diffuse large B-cell lymphoma. Our findings suggest that BCL2 gene translocations are a recurrent feature of a distinct subset of histiocytic sarcomas that are associated with follicular lymphoma; the follicular lymphoma component may be clinically occult at the time of diagnosis. Testing for an IGH/BCL2 translocation should be considered in the diagnostic workup of difficult-to-characterize neoplasms with histiocytic/monocytic morphology and immunoprofile.
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PMID:Two cases of histiocytic sarcoma with BCL2 translocations and occult or subsequent follicular lymphoma. 2713 11

Histiocytic sarcoma is a rare malignant neoplasm that may occur de novo or in the context of a previous hematologic malignancy or mediastinal germ cell tumor. Here, we performed whole exome sequencing and RNA-sequencing (RNA-Seq) on 21 archival cases of primary histiocytic sarcoma. We identified a high number of genetic alterations within the RAS/RAF/MAPK pathway in 21 of 21 cases, with alterations in NF1 (6 of 21), MAP2K1 (5 of 21), PTPN11 (4 of 21), BRAF (4 of 21), KRAS (4 of 21), NRAS (1 of 21), and LZTR1 (1 of 21), including single cases with homozygous deletion of NF1, high-level amplification of PTPN11, and a novel TTYH3-BRAF fusion. Concurrent NF1 and PTPN11 mutations were present in 3 of 21 cases, and 5 of 7 cases with alterations in NF1 and/or PTPN11 had disease involving the gastrointestinal tract. Following unsupervised clustering of gene expression data, cases with NF1 and/or PTPN11 abnormalities formed a distinct tumor subgroup. A subset of NF1/PTPN11 wild-type cases had frequent mutations in B-cell lymphoma associated genes and/or clonal IG gene rearrangements. Our findings expand the current understanding of the molecular pathogenesis of this rare tumor and suggest the existence of a distinct subtype of primary histiocytic sarcoma characterized by NF1/PTPN11 alterations with predilection for the gastrointestinal tract.
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PMID:Genomic profiling of primary histiocytic sarcoma reveals two molecular subgroups. 3223 64

Histiocytic sarcoma (HS) is a rare aggressive hematologic neoplasm that can be associated with low-grade B cell lymphoma. The development of both neoplasms is currently being considered a transdifferentiation mechanism but remains elusive. We report the case of a 65-year-old patient with synchronous development of peritoneal/abdominal HS and grade 1-2 follicular lymphoma (FL). Cytogenetic analysis and targeted next-generation sequencing of both FL and HS tumors identified common genomic alterations such as IGH-BCL2 rearrangement, CREBBP and KMT2D, and aberrations of chromosomes 9q and 19q. However, only the HS tumor had a KRAS mutation while the lymph node involved by FL harbored a TNFAIP3 mutation and both tumors also showed distinct chromosomal alterations. This report strengthens the hypothesis of a common lymphoid progenitor which accumulates genetic alterations leading to two different hematologic malignant diseases with significantly distinct prognoses.
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PMID:Subsequent development of histiocytic sarcoma and follicular lymphoma: cytogenetics and next-generation sequencing analyses provide evidence for transdifferentiation of early common lymphoid precursor-a case report and review of literature. 3180 22