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

Maintenance therapy following induction chemoimmunotherapy in patients with diffuse large B-cell lymphoma: current perspective

BACKGROUND

Maintenance therapy has proven efficacy in indolent non-Hodgkin lymphoma (NHL), yet its role in diffuse large B-cell lymphoma (DLBCL) is an area of ongoing investigation. While DLBCL is potentially curable, >30% of patients relapse following front-line therapy and have a poor prognosis, especially those with refractory disease. Maintenance therapy holds promise to maintain response post-induction.

PATIENTS AND METHODS

Keyword searches were carried out in PubMed and congress abstracts of 'diffuse large B-cell lymphoma' and 'maintenance' and focused on phase II/III studies of maintenance following front-line induction.

RESULTS

Although used in indolent forms of NHL, studies of maintenance therapy with rituximab in patients with DLBCL responding to front-line R-CHOP (rituximab/cyclophosphamide/doxorubicin/vincristine/prednisone) have not improved efficacy and are not recommended. Targeted agents enzastaurin and everolimus reported results from the phase III studies PRELUDE and PILLAR-2, respectively, both of which showed no proven maintenance benefit following front-line chemoimmunotherapy induction. Overall, the reported efficacy results with these agents in the maintenance setting do not outweigh the risks. Lenalidomide for maintenance has been reported in three studies. Results from two phase II trials on lenalidomide maintenance revealed positive outcomes in higher-risk patients following induction, resulting in improved progression-free survival in relapsed DLBCL patients who were ineligible for transplantation. First analysis from the phase III REMARC trial showed a significant improvement in progression-free survival for lenalidomide versus placebo, with no difference in overall survival, following front-line R-CHOP induction in elderly patients.

CONCLUSIONS

Based on currently available studies of DLBCL maintenance therapies, initial results in front-line, as well as the relapsed setting, with immunomodulators such as lenalidomide show promise for further research to identify appropriate patients who would most benefit. Overall, this review of maintenance studies underscores the need for additional analyses of patient subtypes, clinical risk status, and molecular profiles, with careful consideration of study end points.

Rituximab as consolidation therapy did not improve outcome in patients with diffuse large B-cell lymphoma at complete response after dose-dense chemotherapy (CHOP-14)

The authors started a clinical trial to assess the efficacy and toxicity of rituximab (R) as consolidation in patients with diffuse large B-cell lymphoma, with poor prognostic factors, who were in complete response (CR) after dose-dense chemotherapy (CHOP-14). Four hundred sixty-five untreated patients, with advanced stages (III and IV), older (median age >60 years old), and high clinical risk, were treated with dose-dense CHOP-14 (cyclophosphamide 1500 mg/m(2), i.v., day 1; vincristine 2 mg, i.v., standard dose, day 1; epirubicin 120 mg/m(2), i.v., day 1; and prednisone 60 mg/m(2), p.o., days 1-5) every 14 days for six cycles. If CR was achieved, the patients were allocated to receive R (375 mg/m(2), days 1, 8, 15, and 22) at 3 and 9 months after chemotherapy. Three hundred twenty-five patients achieved CR (70%) and were allocated to receive R (151 patients) or not (174 patients). Actuarial curves at 5 years showed that progression-free survival (PFS) was 51% (95% confidence interval [CI]: 44%-58%) in the R group and 53% (95% CI: 47%-59%) in the observation group (p=0.8). Overall survival (OS) was 65% (95% CI: 58%-71%) and 66% (95% CI: 59%-72%), respectively (p=0.78). Late toxicities were more frequent in the R group. The authors showed that the use of R as a consolidation treatment was not useful to improve PFS and OS and toxicity secondary to R was frequent. They did not recommend the use of R as consolidation in this patient setting.

Approach to therapy of diffuse large B-cell lymphoma in the elderly: the International Society of Geriatric Oncology (SIOG) expert position commentary

Diffuse large B-cell lymphoma (DLBCL) is a treatable and potentially curable malignancy that is increasing in prevalence in the elderly. Until recently, older patients with this malignancy were under-represented on clinical treatment trials, so optimal therapeutic approaches for these patients were generally extrapolated from the treatment of younger patients with this disorder. Because of heightened toxicity concerns, older patients were sometimes given reduced dose therapy, potentially negatively impacting outcome. Geriatric considerations including functional status and comorbidities often were not accounted for in treatment decisions. Because of these issues as well as the lack of treatment guidelines for the elderly population, the International Society of Geriatric Oncology convened an expert panel to review DLBCL treatment in the elderly and develop consensus guidelines for therapeutic approaches in this patient population. The following treatment guidelines address initial DLBCL therapy, in both limited and advanced stage disease, as well as approaches to the relapsed and refractory patient.

A randomized trial comparing intensified CNOP vs. CHOP in patients with aggressive non-Hodgkin's lymphoma

The standard CHOP regimen may cure 30-40% of patients with advanced aggressive non-Hodgkin's lymphoma (ANHL). Mitoxantrone is an anthracenedione, which is active in NHL and its toxicity profile may be more favorable than doxorubicin with respect to alopecia, mucositis and cardiotoxicity. This study was designed to compare the effectiveness of an escalated dose of mitoxantrone with that of standard doxorubicin, used in the CHOP regimen in patients with ANHL. One hundred and forty three eligible patients with ANHL were randomized to receive 6 cycles of either CHOP (n = 71) or intensified CNOP (iCNOP) (n = 72), with mitoxantrone 20 mg/m2, i.v., d.1 instead of doxorubicin. Complete responders (CR) were again randomized either to receive interferon-alpha (IFN-alpha) maintenance (3 MU t.i.w., s.c.) or not. The CR rate was 70 vs. 76% for iCNOP and CHOP (p = 0.45), and the overall response rate was 81 vs. 83%, respectively (p = 0.71). The 5-year failure free survival (FFS) was 48 and 50% in the iCNOP and CHOP arm, respectively (p = 0.45), and the 5-year overall survival (OS) was 61 vs. 64% (p = 0.56). IFN-alpha did not prolong relapse free survival (p = 0.91). iCNOP produced less alopecia (p = 0.001) but more febrile episodes (p = 0.04) than CHOP, while requiring more frequent G-CSF support (p = 0.01). Two cases of acute myelogenous leukemia (AML) were recorded, both in the iCNOP arm (p = 0.14). In conclusion, iCNOP was equally effective to CHOP in patients with ANHL, producing more leukopenia and febrile episodes, but less alopecia. The development of two cases of secondary AML in th e iCNOP arm is of concern.