Tumor burden assessment and its implication for a prognostic model in advanced diffuse large-cell lymphoma

Previously untreated adult patients who presented with advanced diffuse large-cell lymphoma (DLCL) at diagnosis were studied to identify possible prognostic factors. One hundred five patients were seen between 1974 and 1981; 45 patients were stage III and 60 patients were stage IV. All patients received cyclophosphamide, doxorubicin, vincristine, prednisone, and bleomycin (CHOP-Bleo). Stage III patients also received radiation therapy alternated with chemotherapy. Overall survival was 50% at 5 years and 43% at 8 years. Seventy-four patients achieved a complete remission (CR) and 37 are alive and disease-free with a median follow-up of 72 months. There was no difference in clinical outcome between stage III and stage IV. However, a proportional hazards model identified lactic dehydrogenase (LDH) level and tumor burden, among all clinical factors studied, as independent risk factors for survival. These two factors were also important for achievement of remission and relapse-free survival. Three distinct patient risk groups were identified with 5-year survival rates of 87%, 48%, and 20%, respectively. The measure of tumor burden proposed herein, along with LDH level, can be used for developing treatment programs, and for meaningful comparison of different treatment regimens, as well as assessment of prognosis.