In the present study, 89 patients with generalized immunocytoma were analyzed retrospectively for the prognostic influence of clinical features and of immunophenotype using bone marrow biopsies. Univariate analysis selected the following variables as significant for survival: age over 60 years (p = 0.021), Rai and Binet stage (p = 0.008 and 0.004, respectively), presence or absence of follicular dendritic cells (FDC, p = 0.036), presence or absence of anemia (p = 0.037). Multivariate regression analysis showed independent prognostic significance of age (p = 0.001), Rai stage (p = 0.003), and the presence of follicular dendritic cells (p = 0.010). Comparing CD5 positive and CD5 negative immunocytomas, no survival advantage for one of the two groups was seen. Presence of follicular dendritic cells clearly identified a favorable prognostic subgroup: of the 89 patients presented, only three of 18 (16.6%) with detectable FDC in bone marrow died within the observation period, as compared to 34 of 71 (52.1%) patients without FDC. Multivariate analysis emphasized the independent prognostic value of the presence of FDC. The high predictive capacity of follicular dendritic cells could add useful information to the commonly used Rai and Binet staging systems for immunocytoma.