Gabriela Gualco

..Molecular studies of the lymph node biopsy showed a point deletion (4-base pair deletion) in exon 9 of the FAS gene (930del TGCT), which results in 3 missense amino acids...

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..Overall survival was worse in adult TCL1-positive cases than pediatric ones. Primary mediastinal large B-cell lymphomas infrequently expressed TCL1 in both age groups...

..TCL1 expression seems to be associated with a good clinical outcome, whereas MUM1 expression predicts a poor clinical outcome...

..Striking differences among geographic regions were seen with the vast majority of EBV subtype B (86%) occurring in the south and southeast regions...

..These findings bear further validation, from comparison to gene expression profiles and from clinical/therapeutic data...

..Patients with non-germinal-center immunophenotype showed significantly worse survival than those with CNS lymphomas of the germinal-center subtype...

..Thirty-two percent of the cases showed a MUM1+/BCL-6-/CD10- phenotype and 56% had a triple-negative-pattern. Aberrant phenotype is infrequent but not rare, and does not rule out a diagnosis of MCL in an otherwise typical case...

..Clonal T-cell receptor gamma and beta gene rearrangements were detected in the T-cell component, whereas monoclonal immunoglobulin H gene rearrangement was found in the Hodgkin cells...

..All cases expressed at least two markers associated with B-cell lineage and good response to combination chemotherapy currently employed for non-Hodgkin lymphomas...

..These cases illustrate the significant difficulties, both clinical and pathological, in achieving the diagnosis of HL involving the stomach in immunocompetent patients...

..None of the cases showed proviral HTLV-1 DNA. ALCL in children has no relationship with HTLV-1; the frequent CD25 expression must be explained by a mechanism different from that in ATLL...

..We reviewed the literature on MUM1/IRF4, with emphasis on the pathologic aspects of this marker in reactive and malignant hematologic and nonhematologic conditions...

..2%, and only rare cases showed p63 expression. BL in Brazil is regionally distinct and has a low incidence of p53 overexpression and a higher-than-expected association with EBV in sporadic cases...

..This study provides the clinical pathological characteristics of 1301 cases of pediatric/adolescent lymphomas in patients from different geographic regions of Brazil...

..Morphologically differential diagnoses considered in the evaluation of this entity and in our case included sarcomas mainly liposarcoma, anaplastic carcinoma, and Hodgkin lymphoma...

..Breast T-cell lymphomas are very infrequent and are morphologically and clinically heterogeneous...

..Primary T-cell lymphomas of the central nervous system are rare, especially in childhood. Here, we describe the rapidly deteriorating and fatal clinical course of a boy with a primary T-cell lymphoma in the central nervous system...