Primary follicular lymphoma of the testis in childhood

BACKGROUND. Follicular lymphoma in childhood is rare. The authors present f our unusual primary follicular lymphomas of the testis in children. METHODS. Tumor tissue was evaluated using light microscopy, immunohistochem istry, flow cytometry, and polymerase chain reaction (PCR) for immunoglobul in heavy chain (IgH) and bcl-2 gene rearrangements. Southern blot and immun ohistochemical analyses were used to detect bcl-6 gene rearrangements and p rotein expression, respectively. RESULTS. Four young boys ranging in age from 3 to 10 pears were diagnosed w ith Stage IE follicular large cell lymphoma (Grade 3). A B-cell phenotype w as documented in all four cases; monoclonality was confirmed in three cases by demonstration of light chain restriction or clonal IgH gene rearrangeme nt. None of the lymphomas expressed Bcl-2 or p53 protein, and bcl-2 gene re arrangements were not found in the three lymphomas studied. In contrast, Bc l-6 protein was expressed by all three lymphomas studied, and a bcl-6 gene rearrangement was detected in the one case analyzed by Southern blot. All f our boys were treated by orchiectomy and combination chemotherapy and are a live with no evidence of disease 18-44 months following their initial diagn oses. CONCLUSIONS. Follicular lymphomas map rarely occur as primary testicular tu mors in prepubertal boys and, when localized, appear to be associated with a favorable prognosis. In contrast to follicular lymphoma in adults, pediat ric follicular lymphomas of the testis are usually of large cell type (Grad e 3) and lack bcl-2 or p53 abnormalities. The identification, in one case, of a bcl-6 gene rearrangement suggests an alternate molecular pathogenesis for pediatric follicular lymphoma. (C) 1999 American Cancer Society.