R-CHOP with or without Lenalidomide/Bortezomib As a First Line Treatment for Patients with Non-Germinal Center Diffuse Large B Cell Lymphoma (DLBCL) Subtype: Son Espases University Hospital Experience

Abstract INTRODUCTION The standard first line treatment for patients with diffuse large B-cell lymphoma (DLBCL) is rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) independently of cell origin subtype. Retrospective studies have shown that non-germinal center (NGC) subtype is associated with a worse progression free survival (PFS) and overall survival (OS) compared to germinal center subtype. In phase II studies the combination of lenalidomide (lena) or bortezomib (bor) with R-CHOP in this lymphoma subtype has shown better results in comparison to R-CHOP alone. For this reason, the aim of our study is to analyze the efficacy and toxicity of R-CHOP plus lena/bor in comparison with R-CHOP alone in patients with NGC DLBCL. PATIENTS AND METHODS In order to avoid selection bias, all patients with NGC DLBCL (confirmed by immunohistochemistry with Hans algorithm) who received R-CHOP or R-CHOP-lena/bor (25mg lenalidomide daily from day 1 to 10 / bortezomib 1.3mg/m2 days 1 and 4) were retrospectively selected from the Pharmacy Registry. Patients in our center received R-CHOP from March 2002 to June 2013, R-CHOP-bor from June 2013 to July 2015 and R-CHOP-lena from November 2014 until now. Cheson and Lugano criteria were used to confirm response rates. Toxicity was checked with CTCAE v4-5 criteria. RESULTS Fifty-five patients with NGC DLBCL were identified from 2002 to 2018, 18 of whom were treated with R-CHOP-lena/bor and 33 with R-CHOP. Baseline characteristics are specified in Table 1. Overall response rate was similar in both treatment regimens, 94% versus 87%, respectively. 12.5% progression/stable disease cases were identified with R-CHOP alone compared to 5.3% with R-CHOP-lena/bor. With a median follow-up of 45 months (6-126) for R-CHOP and 22 months (6-59) for R-CHOP-lena/bor, the median PFS was 65 months for R-CHOP and was not reached for R-CHOP-lena/bor. 47% versus 9% of progressions were observed in R-CHOP and R-CHOP-lena/bor, respectively (p=0.006). Regarding OS, the death rate in the R-CHOP group was 45% in comparison with 23% in R-CHOP-lena/bor group (p=0.015). Higher hematological toxicity was observed in the R-CHOP-lena/bor group comparing with R-CHOP: neutropenia (95% versus 68%), grade 3-4 neutropenia (81% versus 37%) and anemia (81% vs 56%) (p<0.05) (Table 2) being manageable in all cases. CONCLUSIONS The addition of lenalidomide or bortezomib to R-CHOP seems to be a good option in NGC DLBCL, with a lower progression rate, refractoriness and less mortality in comparison with R-CHOP alone. R-CHOP-lena/bor is associated to higher rates of hematological toxicity but manageable in all cases. These retrospective data should be confirmed in ongoing phase III clinical trials. Disclosures No relevant conflicts of interest to declare.