Células dendríticas foliculares: avaliação imunofenotípica no linfoma de Hodgkin clássico subtipo esclerose nodular

Abstract

The follicular dendritic cells are the most important antigen presenting cells and have an important role in B cell immune response. Classic Nodular Sclerosis Hodgkin's Lymphoma (CNSHL) is a lymphoid neoplasm, more specifically from germinal center (GC) B cells, presenting with aggregates of follicular dendritic cells (FDC), Hodgkin/Reed Sternberg cells and variants and B cells forming complexes related to the GC, suggesting an association between nodular sclerosis and germinal center formation. CNSHL represents 70% of classic Hodgkin's lymphomas and has a favorable prognosis. Histologically it is characterized by a nodular pattern, collagen bands and lacunar cells. The goal of this study was the evaluation of the follicular dendritic cell by immunophenotyping with pS100 and fascin, in lymph node or mediastinal mass biopsies from patients with previously diagnosed classic nodular sclerosis Hodgkin's Lymphoma, trying to identify criteria as prognostic factors. 159 charts were reviewed and 38 patients were selected for the study. From the selected group 55.2% were males with a male to female ratio of 1.23:1 and a median age of 29.3 years. 52.6% were in clinical stage 1-11 and 68.4% had systemic symptoms (B). Multiple or isolated peripheral adenomegaly was present in all cases. The first lymph node site was cervical in 58% of the cases. 38 biopsy specimens were analysed and 57.9% were of nodular sclerosis subtype II. Immunohistochemistry showed 100% positivity for CD30 and 68.4% for CD15. The follicular dendritic cells were identified by pS100 and fascin antibodies through the Peroxidase-antiperoxidase Streptavidin avidin-biotin indirect immunoenzimatic technique, which was performed in pre-treated slides with the biopsy specimens included in paraffin blocks. The marking with pS100 didn't show good visualization of the network of follicular dendritic cells, and was useful as a generic marker. Fascin was the gold-standard for follicular dendritic cells, showing its positivity by the brown color. The CDF1 pattern was present in 7.9%, CDF2 in 47.4% and CDF3 in 44.7%. There was no relation between the presence of the follicular dendritic cell and sex, age, clinical stage, laboratorial parameters, or response to treatment, but a tendency for the association (p=0.056) between the subtypes of classical nodular sclerosis Hodgkin's lymphoma was demonstrated. The patients with follicular dendritic cells present in their biopsies have been watched for a longer period of time of about 32.9 months. This enabled a significant statistical association (p=0.001) between the presence of follicular dendritic cells and length of follow-up