Expression of immunohistochemical markers in patients with AIDS-related lymphoma

AIDS-related lymphomas (ARL) present high biological heterogeneity. For better characterization of this type of lymphoma, the objectives of the present study were to evaluate the expression of immunohistochemical markers of cell differentiation (CD10, Bcl-6, MUM-1) and determine cell origin profile according to Hans' classification of diffuse large B-cell lymphoma in AIDS patients. This study included 72 consecutive patients with ARL diagnosed at the University Hospital, Universidade Federal do Rio de Janeiro (UFRJ) and at the Brazilian Instituto Nacional de Câncer (INCA) from 2000 to 2006. The morphologic distribution of the lymphomas was the following: 61 percent were diffuse large B-cell lymphomas (DLBCLs), 15 percent were Burkitt's lymphomas, 13 percent were plasmablastic lymphomas, 10 percent were high-grade lymphomas and 1 percent was follicular lymphoma. The positivity for each immunohistochemical marker in DLBCLs, Burkitt's lymphoma and plasmablastic lymphoma was respectively: CD20, 84 percent, 100 percent, and 0; CD10, 55 percent, 100 percent, and 0; Bcl-6, 45 percent, 80 percent, and 0; MUM-1, 41 percent, 20 percent, and 88 percent. A higher positivity of CD20 (84 percent x 56 percent, p = 0.01) was found in DLBCL compared to non-DLBCL; in Burkitt's lymphomas a higher positivity of CD10 (100 percent x 49 percent, p = 0.04) and Bcl-6 (80 percent x 39 percent, p = 0.035) were found compared to non-Burkitt's lymphomas. Germinal center (GC) profile was detected in 60 percent of DLBCLs. Our study suggests particular findings in ARL, as the most frequent phenotype was GC, different from HIV-negative patients.

Linfomas asociados con la infección por el virus de la inmunodeficiencia humana: subtipos histológicos y asociación con los virus de Epstein Barr y Herpes-8 / AIDS related lymphomas: Histopathological subtypes and association with Epstein Barr virus and Human Herpes virus type-8

Los linfomas no Hodgkin (LNH) constituyen la segunda neoplasia definitoria de Sida más frecuente. En el presente trabajo se evaluaron 48 casos de linfomas asociados con la enfermedad debida al virus de la inmunodeficiencia humana (HIV) diagnosticados en la División Histopatología del Instituto de Investigaciones Hematológicas de la Academia Nacional de Medicina. Se incluyeron en la investigación 5 mujeres y 43 hombres con una mediana de edad al momento del diagnóstico de la neoplasia de 37 años. La evaluación morfológica se realizó en cortes coloreados con hematoxilina-eosina, estudio inmunohistoquímico para la detección del virus de Epstein Barr (VEB) en 48/48 casos, y mediante sonda oligonucleotídica biotinilada para la detección del ADN del Herpes virus humano tipo-8 (HHV-8) en 14/14 linfomas plasmoblásticos (LP). Todos fueron linfomas de fenotipo B, con un curso clínico agresivo y enfermedad neoplásica avanzada al momento del diagnóstico. Se pudo demostrar la fuerte asociación del VEB con los linfomas asociados al sida, con frecuencias que variaron según el subtipo histológico: 16/21 (76%) para los linfomas difusos de grandes células; 1/3 casos (33%) de linfomas de Burkitt y 3/4 (75%) en los linfomas primarios del sistema nervioso central. Globalmente, el genoma del VEB se detectó en 20/28 (71%) de las muestras de biopsias de LNH de esta serie. La detección del HHV-8 resultó negativa en los 14 LP. Los linfomas de Hodgkin fueron más frecuentes en varones,18/20 (90%), con un curso clínico agresivo y franco predominio de los subtipos histológicos de peor pronóstico (90% de casos). En estas neoplasias también se comprobó una frecuente asociación patogénica con el VEB (90% de casos).

Non-Hodgkin lymphomas (NHL) of the B-cell type are the second most common neoplasm among patients with human immunodeficiency virus (HIV) infection and AIDS. Here, we evaluated 48 cases of AIDS-related lymphomas (ARL) diagnosed at the Histopathological Division of the Instituto de Investigaciones Hematológicas of the National Academy of Medicine. Five were females and 43 were males with a median of age of 37 years at the time of the diagnosis. Micrometer sections were prepared and stained with hematoxilin-eosin; immunohistochemical examination for the presence of Epstein-Barr virus (EBV) was carried out in 48/48 cases. Additionally, biotinilated oligonucleotides were used to determine the presence of DNA of the Human Herpes virus type-8 (HHV-8) in 14/14 biopsy smears corresponding to plasmablastic lymphomas (PL). All were fenotype B cell lymphomas with an aggressive course and advanced neoplasm disease at the time of diagnosis. Virological findings showed the strong association between EBV and AIDS-related NHL. According to the histopathological subtype, the EBV genome was detected in 16/21 (76%) diffuse large B cell lymphomas, 1/3 Burkitt lymphoma and 3/4 (75%) of primary central nervous system lymphomas. Globally, EBV genome was detected in 20/28 NHL of this series. Detection of HHV-8 was negative in all cases of PL. Hodgkin lymphoma were more frequent in males 18/20 (90%), with an aggressive clinical course and a significant predominance of the subtypes associated with worse prognosis (90% of cases). We detected a significant association between EBV and HL (90% of cases). We consider that all cases of AIDS related lymphomas should be assessed for the presence of EBV because its presence may play a role in the prognosis.