Interferon alfa 2b as maintenance therapy in poor risk diffuse large B-cell lymphoma in complete remission after intensive CHOP-BLEO regimens

Objectives: We conducted a randomized clinical trial to evaluate the role o f interferon alfa 2b (IFN) as maintenance therapy in patients with diffuse large B-cell lymphoma with high or high-intermediate clinical risk on compl ete remission (CR) after CHOP-BLEO regimens. Methods: Patients were initial ly treated with CHOP-BLEO regimens (which include increased doses of cyclop hosphamide and epirubicine, instead of doxorubicin). If the patients achiev ed CR they were randomly assigned to receive either maintenance therapy wit h IFN 5.0 MU, three times at week by 1 yr, or no treatment (control group). Results: Two hundred and twenty-three patients were considered as candidat es for the study. They were of high (80%) or high-intermediate (20%) clinic al risk; additionaly most patients had poor prognostic factors such as high levels of beta 2 microglobulin, lactic dehydrogenase levels, bulky disease (defined as a tumor mass > 10 cm) or multiple extranodal involvement. In a n intent-to-treat analysis all patients were evaluable to efficacy and toxi city. Median follow-up was 45 months, the estimated 5-yr overall survival a nd event-free survival (EFS) for patients who received IFN were 71% (95% co nfidence interval (CI): 61-83%) and 57% (95% CI: 39-69%), respectively, val ues which were not statistically different from the control group: 69% (95% CI: 63-79%) and 54% (95% CI: 37-63%), respectively (p = 0.2). Toxicity was mild. Conclusions: These results suggest that IFN used as maintenance therapy at these doses and schedules is not useful in aggressive malignant lymphoma wh en more intensive chemotherapy has been employed during induction treatment . Nevertheless, follow-up is too short, and long-term follow-up would be ne cessary in order to draw definitive conclusions. Probably, an multicenter s tudy is necessary to define the role of IFN as maintenance therapy in this patient setting.