Non-Hodgkin malignant lymphomas of B-cell lineage with special reference to their lymph node involvement pattern.

A total number of 137 lymph nodes from 33 patients with a malignant non-Hodgkin lymphoma of B-cell lineage was assessed histologically and immunohistochemically with special reference to the presence or absence of the neoplastic B-cells in the B- and T-cell areas of the lymph nodes as well as inside the post-capillary venules (PCV) of the paracortical areas. The B-cell origin of the lymphomas was confirmed by staining the tissues with an indirect immunoperoxidase technique for the cell surface immunoglobulins. The B-cell areas (cortex and medulla) of the lymph nodes were involved by the lymphoma cells in all studied cases. The T-cell areas (paracortex) were involved in 93.4% of the nodes. Lymphoma cells were encountered inside th PCV in 83.2% of the nodes. Furthermore, fifteen nodes were found where the T-cell area was only partially involved despite the totally involved B-cell areas. The results lend some support to the view that the lymph node involvement by the B-cell neoplasias starts from the B-cell areas. This involvement pattern may be used as an aid in the diagnosis of these lymphomas, and utilized in the study of the circulatory properties of the B-lymphocytes in general.