Immunobiologic factors predictive of clinical outcome in diffuse large-cell lymphoma.

The prognostic importance of immunobiologic factors in diffuse large-cell lymphoma (DLCL) is studied in 105 consecutive DLCL patients. Multivariate results using the Cox proportional hazards model clearly indicate that the Ki-67 index (P = .002), a marker of cell proliferation activity, and the presence or absence of human leukocyte antigen-DR (HLA-DR) (P = .007) are strong predictors of survival even in the presence of established clinical factors of stage (P = .015) and symptoms (P = .050). Using these four variables, prognostic groups were formed identifying patient groups with varying degrees of risk. The group of patients with three or four risk factors present at the time of diagnosis had a median survival of 4 months compared with a median survival of 59 months for the group with no risk factors. Similarly, prognostic groups for disease-free survival (DFS) were constructed based on the proportional hazards model that involved B versus T phenotype (P = .035) and HLA-DR (P = .054). Median DFS for the patient group with one or two risk factors present was 11 months compared with 43 months with no risk factors present. This study suggests immunobiologic parameters are important predictors of clinical outcome in DLCL patients and are of value in identifying subgroups of patients who have not responded to currently available therapy. The practical significance of this study is to identify parameters that may suggest specific changes in therapy of patient subgroups.