Purpose: Prognostic factors in low grade non-Hodgkin's lymphoma (LGL) are not well established. The aim of this study is to investigate prognostic factors on LGL treated in our institution during the last decade.
Patients and methods: The study was carried out on 70 cases of newly diagnosed LGL, most treated with CVP or clorambucil and prednisone. The median follow-up was 37 months (1-132). Variables reported as prognostic factors in previous series were subjected to bivariate and multivariate analysis.
Results: Relevant clinical features were: Ann Arbor III-IV stage 74%, ECOG > or = 2-17%, bone marrow involvement 60% and large tumor burden according to MD Anderson criteria 21%. Complete response (CR) was achieved in 50% and partial response in 29%. In bivariate analysis factors related with poor CR were B symptoms, large tumor burden, high LDH and more than one extranodal site involvement. Logistic regression showed that large tumor burden (p = 0.02; OR = 0.07) and B symptoms (p = 0.07; OR = 0.14) were the best prognostic factors of poor CR. Five year global survival (GS) was 55%, with a median of 76 months. In univariate analysis factors related with GS were ECOG > or = 2, B symptoms, bulky, large tumor burden, retroperitoneo involvement and absence of CR. In multivariate analysis the only factor related with poor GS was large tumor burden (p < 0.00001; RR = 5.93). When therapeutic response was included in the model, absence of CR (p = 0.008; RR = 3.40) and large tumour burden (p = 0.005; RR = 3.86) were the factors selected.
Conclusions: In LGL tumor burden was the most important prognostic variable. Tumor response showed less importance than in high grade lymphomas.