EXPRESSION OF P53 IN PEDIATRIC LYMPHOMAS FROM MEXICO - RELATION TO HISTOLOGY AND IMMUNOPHENOTYPE

Eighty-five cases of pediatric non-Hodgkin's lymphomas (NHLs) from Mex ico have been reviewed and classified according to histologic type and immunophenotype using a panel of markers which included CD20, CD45RO- (UCHLI), CD3 and Tdt. Twenty-five cases were classified as lymphoblast ic lymphoma (LBL) of precursor cell origin and forty-nine cases as non -lymphoblastic lymphomas. Eleven cases could not be satisfactorily cla ssified due to insufficient tissue or on technical grounds. All these lymphomas were subjected to immunohistochemistry (IHC) for detecting p 53 expression. p53 was detectable in 7 (28%) lymphoblastic lymphomas, in 36 (73.4%) non-lymphoblastic lymphomas and in 4 (36.3%) of the lymp homas that could not be classified. Our results indicate that in contr ast to adults with NHL and children with acute leukemia, p53 expressio n is relatively frequent in pediatric NHLs, although it is higher in l ymphomas of B cell phenotype than in those of T cell type.