B- and T-cell markers in lymphoproliferative disorders with blood and bone marrow involvement.

B- and T-cell surface markers were determined in 26 adult patients with lymphoproliferative malignancies who had bone marrow and blood involvement. The patients in whom more than 60% of the abnormal cells were immunoglobulin-bearing cells were considered to have B-cell lymphoproliferative malignancy. The diagnosis of a T-cell disorder was made in those patients in whom more than 70% of the cells formed E rosettes (T cells). Those patients in whom 30% and more of the abnormal cells did not show B- and T-cell surface markers were regarded as suffering from "null" cell disorder. The B-cell type of lymphoproliferative malignancy was the most commonly encountered (63%) with an equal male to female ratio. In addition, 4 male patients with "hairy-cell" leukaemia were shown to have a B-cell disorder. T-cell disorders were found in 3 male patients; 1 patient had acute lymphoblastic leukaemia and in the other 2 the histopathological diagnosis was well-differentiated lymphoma and Sternberg sarcoma. Four patients with "null" cell lymphoma were found, the histopathological diagnoses in all were poorly-differentiated lymphocytic lymphoma, and 3 of the 4 patients were males. Further haematological investigations of the B-cell and the non-B-cell disorders showed that although the bone marrow was equally extensively infiltrated in both groups, the non-B-cell disroders were more commonly associated with complications of anemia and thrombocytopenia. It is therefore postulated that the abnormal lymphoid cell involved in B-cell disorders is an end-stage cell and not the haemopoietic stem cell.