MUC4 Expression in Angiomatoid Fibrous Histiocytoma.

Angiomatoid fibrous histiocytoma (AFH) is a rarely metastasizing neoplasm that typically occurs in the deep dermis and subcutis of the extremities of young patients, characterized by a t(2;22) translocation involving EWSR1 and CREB1. Because of its distinctive histologic features, the diagnosis of AFH is generally straightforward, although the immunohistochemistry (IHC) findings are relatively nonspecific. We recently encountered a case of primary cranial AFH that showed strong MUC4 IHC expression, which has not yet been reported previously.

Geographic differences in the distribution of molecular subtypes of breast cancer in Brazil.

Background: To compare the distribution of the intrinsic molecular subtypes of breast cancer based on immunohistochemical profile in the five major geographic regions of Brazil, a country of continental dimension, with a wide racial variation of people.

Methods: The study was retrospective observational. We classified 5,687 invasive breast cancers by molecular subtype based on immunohistochemical expression of estrogen-receptor (ER), progesterone-receptor (PR), human epidermal growth factor receptor 2 (HER2), and Ki-67 proliferation index.

Burkitt lymphoma mimicking acute pancreatitis.

Burkitt lymphoma (BL) is a highly aggressive B cell lymphoma, presenting in extranodal sites or as an acute leukemia. Three clinical variants of BL are recognized: endemic BL, sporadic BL and immunodeficiency associated BL. Sporadic BL is seen worldwide, mainly in children and young adults involving the abdominal organs mostly the ileocaecal area.

The contribution of HGAL/GCET2 in immunohistological algorithms: a comparative study in 424 cases of nodal diffuse large B-cell lymphoma.

Diffuse large B-cell lymphoma can be subclassified into at least two molecular subgroups by gene expression profiling: germinal center B-cell like and activated B-cell like diffuse large B-cell lymphoma. Several immunohistological algorithms have been proposed as surrogates to gene expression profiling at the level of protein expression, but their reliability has been an issue of controversy. Furthermore, the proportion of misclassified cases of germinal center B-cell subgroup by immunohistochemistry, in all reported algorithms, is higher compared with germinal center B-cell cases defined by gene expression profiling.

Triple-negative breast carcinomas are a heterogeneous entity that differs between young and old patients.

Objective: To compare the frequency and immunohistochemical profiles of triple-negative breast carcinomas in younger and older women.

Methods And Results: We selected patients diagnosed with triple-negative breast carcinomas. The groups examined were women who were 35 years old or younger between 1997 and 2007 (n = 74) and, for comparison, women who were 60 years old or older (n = 19, consecutive cases).

DOG1 for the diagnosis of gastrointestinal stromal tumor (GIST): Comparison between 2 different antibodies.

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal neoplasm of the gastrointestinal tract. Discovered on GIST-1 (DOG1) is a recently described protein expressed in GISTs irrespective of mutation status. The aim of this study was to investigate the immunohistochemical expression of DOG1 using 2 different monoclonal antibodies (DOG1.

Hodgkin's lymphoma presenting as dominant gastric lesion in immunocompetent patients: report of 5 cases with EBV analysis.

Primary Hodgkin's lymphoma (HL) of the stomach is an extremely rare entity. Most cases of gastric involvement by HL are observed in the setting of disseminated disease. The nonspecific nature of the symptoms and endoscopic findings, which include a large malignant-looking ulcer and mass or wall thickening, together with the considerable histological overlap between HLs and some non-HLs or undifferentiated carcinoma, make the surgical resection diagnosis extremely difficult.

Autoimmune lymphoproliferative syndrome in a patient with a new minimal deletion in the death domain of the FAS gene.

We present a case of autoimmune lymphoproliferative syndrome (ALPS) caused by a previously undescribed minimal deletion in the death domain of the FAS gene. ALPS is an uncommon disease associated with an impaired Fas-mediated apoptosis. The patient presented with a history of splenomegaly since 4 months of age, associated with cervical lymphadenopathy, which improved with oral corticosteroid treatment.