Primary T-cell malignant lymphoma of the central nervous system. Histological, immunohistochemical and ultrastructural study of a case.
Most primary malignant lymphomas (ML) of the central nervous system (CNS) are derived from B-cells, whereas T-malignant lymphomas (T-ML) primarily arising in the CNS are extremely rare. We report on a patient with a primary T-ML of the CNS localised in the posterior fossa. On the basis of histological, ultrastructural and immunohistochemical studies, this tumour was classified as a pleomorphic T-ML, medium and large cell type with peripheral helper/inducer T-cell phenotype (CD 1-, CD 2+, CD 3+, CD 5+, CD 7-, CD 4+, CD 8-, CD 19-, CD 22-, UCHL 1+/CD 45 RO, L 26-/CD 20, LN 1-/CDW75, LN 2-/CD 74, MB 2-). Furthermore, the positivity of the markers CD 25 and HLA-DR on many medium-sized and large lymphoma cells suggests activation of these cells. The nuclear marker of proliferative activity Ki-67 was expressed in some large cells, whereas the natural killer cell-related markers CD 16 and Leu 7/CD 57 did not react with lymphoma cells. This study emphasises the value of extensive immunohistochemical investigations on frozen and paraffin sections in order to identify and characterize the T-cell malignancies, particularly in their rare CNS location.
Department of Pathology, Lariboisière Hospital, Faculté Lariboisière-Saint-Louis, Paris, France.
P
P
Kanavaros
J
J
Mikol
J
J
Nemeth
A
A
Galian
J
J
Vaunaize
F
F
Morinet
C
C
Thurel
D015703:Antigens, CD / Q000032:analysis*; D000951:Antigens, Neoplasm / Q000032:analysis*; D001932:Brain Neoplasms / Q000276:immunology / Q000648:ultrastructure*; D005260:Female; D006801:Humans; D016399:Lymphoma, T-Cell / Q000276:immunology / Q000648:ultrastructure*
D015703:Antigens, CD; D000951:Antigens, Neoplasm