Lymphoid subsets and prognostic factors in multiple myeloma. Cooperative Group for the Study of Monoclonal Gammopathies.

In a uniform series of 170 untreated myeloma patients (MM) we investigated the distribution of T cell subsets in peripheral blood (PB) and their relationship with the most relevant disease characteristics, including survival. CD4 cells were significantly decreased both in percentage and absolute numbers (P less than 0.0001). On the other hand, the CD8 cells only showed a slight increase in relative numbers. Upon correlating the abnormalities in the distribution of T cells with other clinical and biological disease characteristics the most remarkable correlation was with survival. A low number of CD4 cells (less than 700 x 10(6)/l) was associated with both an advanced clinical stage and a shorter survival (20 v. 43 months, P = 0.01). Moreover, a significant correlation also exists between the decrease in CD4 cells and both high beta 2-microglobulin (beta 2M) levels and anaemia. On the other hand, no relationship was found with the type of M-component nor with the plasma cell phenotype. Finally multivariate analysis showed that the number of CD4 cells add independent prognostic information to other well-established tests for the assessment of disease outcome in patients with multiple myeloma.