Do pathologic features predict prognosis in diffuse large B-cell lymphoma?

We analyzed 47 immunologically confirmed cases of diffuse large B-cell lymphoma (DLBL) to determine whether the histologic type, surface immunoglobulin (Ig) phenotype, or mitotic rate predicted the clinical outcome. All patients were uniformly staged and uniformly treated with one six-drug protocol. Seventeen cases were subclassified as the noncleaved cell type (DLBL-NC), 23 cases as the immunoblastic type (DLBL-IBL), and 7 cases as other follicular center cell (FCC) types (DLBL-O). The predicted two-year actuarial survival for patients with DLBL-O (82%) was significantly longer than for those with DLBL-NC (35%; p = 0.05). The immunologic phenotype and mitotic rate also predicted the clinical outcome. The predicted two-year survival for patients with DLBL having a surface IgM phenotype (29%; p = 0.06), and the two-year survival for patients with FCC-derived DLBL (DLBL-NC plus DLBL-O) having a surface IgG phenotype (80%) was significantly longer than for those with a surface IgM phenotype (0%; p = 0.02). Similarly, the two-year survival for patients with DLBL having less than 30 mitoses (68%) was significantly longer than for those having greater than or equal to 30 mitoses per 10 high-power fields (28%; p = 0.01). These findings are considered preliminary, and additional studies of a large number of similar patients are necessary for their confirmation.