Application of Lenalidomide on Diffused Large B-cell Lymphoma: Salvage, Maintenance, and Induction Treatment

Efficacy and Safety of Lenalidomide Monotherapy for Relapsed/Refractory Diffuse Large B Cell Lymphoma: Systematic Review and Meta-Analysis

INTRODUCTION

Several maintenance therapies are available for treatment of patients with relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL). The objective of this review was to assess the efficacy and safety of lenalidomide monotherapy in these patients.

METHODS

MEDLINE, EMBASE, and the Cochrane Library databases were searched for publications up to April 7, 2021. Original studies that had information on lenalidomide monotherapy for DLBCL patients with R/R status were included. Meta-analyses of response rates, adverse events (AEs), overall survival (OS), and progression-free survival (PFS) were performed. The pooled event rates were calculated using a double arcsine transformation to stabilize the variances of the original proportions. Subgroup analysis was used to compare patients with different germinal center B-cell-like (GCB) phenotypes.

RESULTS

We included 11 publications that examined DLBCL patients with R/R status. These studies were published from 2008 to 2020. The cumulative objective response rate (ORR) for lenalidomide monotherapy was 0.33 (95% CI: 0.26, 0.40), and the ORR was better in patients with the non-GCB phenotype (0.50; 95% CI: 0.26, 0.74) than the GCB phenotype (0.06; 95% CI: 0.03, 0.11). The major serious treatment-related AEs were neutropenia, thrombocytopenia, respiratory disorders, anemia, and diarrhea. The median PFS ranged from 2.6 to 34 months and the median OS ranged from 7.8 to 37 months.

CONCLUSION

This study provides evidence that lenalidomide monotherapy was active and tolerable in DLBCL patients with R/R status. Patients in the non-GCB subgroup had better responsiveness.

Characterization of Artificial Pneumothorax-Unrelated Pyothorax-Associated Lymphoma

Pyothorax-associated lymphoma (PAL) is a rare disease developing from a long-term pleural cavity inflammation. Most reported PAL cases have a history of artificial pneumothorax. However, the clinical features of artificial pneumothorax-unrelated PAL remain largely unknown. Here, we reported two PAL cases diagnosed from our center in the past ten years. One case developed from asymptomatic pyothorax after pneumonectomy with a latency of 28 years, while the other case showed a relatively short latency of one year. Then we reviewed the literature of artificial pneumothorax-unrelated PAL by searching PubMed and Google Scholar from 2007. In total, nine artificial pneumothorax-unrelated PAL cases were found, predominantly in old male with median age of 76 years (ranging from 51 to 88). Most cases were diagnosed with diffuse large B-cell lymphoma (DLBCL) (n = 8, 88.9%) and had evidence of Epstein-Barr virus (EBV) infection (n = 6, 66.7%) or tuberculous pleurisy (n = 5, 55.6%). Notably, four cases (44.4%) had short intervals (no more than two years) between pleuritis and PAL. Regarding the overall survival, one-third cases survived more than 5 years after the diagnosis of PAL. In conclusion, the features of artificial pneumothorax-unrelated PAL are comparable with the classic type of PAL, except for some patients with short duration of pleuritis, and need to be identified. Treatment guideline of DLBCL is recommended for the management of PAL.

R-CHOP resistance in diffuse large B-cell lymphoma: biological and molecular mechanisms

Although the first-line rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone regimen (R-CHOP) substantially improved outcomes for patients with diffuse large B-cell lymphoma (DLBCL), 40% of the patients suffered from relapsed/refractory disease and had poor survival outcomes. The detailed mechanism underlying R-CHOP resistance has not been well defined. For this review, we conducted a thorough search for literature and clinical trials involving DLBCL resistance. We discussed DLBCL biology, epigenetics, and aberrant signaling of the B-cell receptor (BCR), phosphatidylinositol 3-kinase (PI3K)/Akt, nuclear factor kappa light chain enhancer of activated B-cells (NF-κB), and the Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathways as defining mechanisms of DLBCL heterogeneity and R-CHOP resistance. The cell of origin, double- or triple-hit lymphoma and double-protein-expression, clonal evolution, tumor microenvironment, and multi-drug resistance help to contextualize DLBCL resistance in an (epi)genetically and biologically comparative manner. With better understanding of the biological and molecular landscape of DLBCL, a more detailed classification system and tailored treatments will ideally become available to further improve the prognosis of DLBCL patients.