Attenuated immunochemotherapy regimen (R-miniCHOP) in elderly patients older than 80 years with diffuse large B-cell lymphoma: a multicentre, single-arm, phase 2 trial.

Background: Diffuse large B-cell lymphoma is a common cancer in elderly patients. Although treatment has been standardised in younger patients, no prospective study has been done in patients over 80 years old. We aimed to investigate the efficacy and safety of a decreased dose of CHOP (doxorubicin, cyclophosphamide, vincristine, and prednisone) chemotherapy with a conventional dose of rituximab in elderly patients with diffuse large B-cell lymphoma.

Methods: We did a prospective, multicentre, single-arm, phase 2 study of patients aged over 80 years who had diffuse large B-cell lymphoma. Patients were included from 38 centres in France and Belgium. All patients received six cycles of rituximab combined with low-dose CHOP (R-miniCHOP) at 3-week intervals. Patients received 375 mg/m(2) rituximab, 400 mg/m(2) cyclophosphamide, 25 mg/m(2) doxorubicin, and 1 mg vincristine on day 1 of each cycle, and 40 mg/m(2) prednisone on days 1-5. The primary endpoint was overall survival, both unadjusted and adjusted for treatment and baseline prognostic factors. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, NCT01087424.

Findings: 150 patients were enrolled between Jan 9, 2006, and Jan 23, 2009 and 149 were included in the intention-to-treat analyses. Median age was 83 years (range 80-95). After a median follow-up of 20 months (range 0-45), the median overall survival was 29 months (95% CI 21 to upper limit not reached); 2-year overall survival was 59% (49-67%). In multivariate analyses, overall survival was only affected by a serum albumin concentration of 35 g/L or less (hazard ratio 3·2, 95% CI 1·4-7·1; p=0·0053). Median progression-free survival was 21 months (95% CI 13 to upper limit not reached), with a 2-year progression free survival of 47% (38-56). 58 deaths were reported, 33 of which were secondary to lymphoma progression. 12 deaths were attributed to toxicity of the treatment. The most frequent side-effect was haematological toxicity (grade ≥3 neutropenia in 59 patients; febrile neutropenia in 11 patients).

Interpretation: R-miniCHOP offers a good compromise between efficacy and safety in patients aged over 80 years old. R-miniCHOP should be considered as the new standard treatment in this subgroup of patients.

Funding: Groupe d'Etude des Lymphomes de l'Adulte (GELA).