This study aimed to assess the efficacy and safety of treatment with avelumab, an anti-programmed death ligand 1 (PD-L1) antibody, in patients with relapsed or refractory extranodal natural killer (NK)/T-cell lymphoma (ENKTL). In this phase II trial, 21 patients with relapsed or refractory ENKTL were treated with 10 mg/kg of avelumab on days 1 and 15 of a 28-day cycle (ClinicalTrials.gov Identifier: NCT03439501). The primary end point was the complete response (CR) rate based on the best response. Targeted sequencing and immunohistochemistry were performed using pretreatment tumor tissue, and blood samples were drawn pre- and post-treatment for measurement of cytokines and soluble programmed cell death protein 1 (PD1), PD-L1, and PD-L2. The CR rate was 24% (5/21) and the overall response rate was 38% (8/21). Although nonresponders showed early progression, five responders currently continue to receive treatment and have maintained their response. Most treatment-related adverse events were grade 1 or 2; no grade 4 adverse events were observed. Treatment responses did not correlate with mutation profiles, tumor mutation burden, serum levels of cytokines, or soluble PD1/PD-L1 and PD-L2. However, the response to avelumab was significantly associated with the expression of PD-L1 by tumor tissue (P = 0.001). Therefore, all patients achieving CR showed high PD-L1 expression, and their tumor subtyping based on PD-L1 expression correlated with treatment response. In conclusion, avelumab showed single-agent activity in a subset of patients with relapsed or refractory ENKTL. The assessment of PD-L1 expression on tumor cells might be helpful for identifying responders to avelumab.

This meta-analysis evaluates the efficacy and safety of chimeric antigen receptor (CAR) T-cell therapy and bispecific antibodies for relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL). We searched MEDLINE, Embase, and Cochrane databases until July 2023 for trials assessing CAR T-cell therapies and CD20×CD3 bispecific antibodies as third or subsequent lines in R/R DLBCL. Random-effects models estimated the complete response (CR) rate and secondary outcomes, with meta-regressions adjusting for relevant covariates. Sixteen studies comprising 1347 patients were included in the pooled analysis. The pooled CR rate for bispecific antibodies was 0.36 (95% confidence interval [CI], 0.29-0.43), compared with 0.51 (95% CI, 0.46-0.56) for CAR T-cell therapy (P < .01). This superiority persisted when comparing the CAR T-cell–naive patients within the bispecific antibody group, with a CR rate of 0.37 (95% CI, 0.32-0.43). Multivariable meta-regression also revealed better efficacy of CAR T cells with adjustment for the proportion of double-hit lymphoma. The pooled 1-year progression-free survival rate mirrored these findings (0.32 [95% CI, 0.26-0.38] vs 0.44 [95% CI, 0.41-0.48]; P < .01). For adverse events of grade ≥3, the bispecific antibody had incidences of 0.02 (95% CI, 0.01-0.04) for cytokine release syndrome, 0.01 (95% CI, 0.00-0.01) for neurotoxicity, and 0.10 (95% CI, 0.03-0.16) for infections. The CAR T cell had rates of 0.08 (95% CI, 0.03-0.12), 0.11 (95% CI, 0.06-0.17), and 0.17 (95% CI, 0.11-0.22), respectively, with significant differences observed in the first 2 categories. In summary, CAR T-cell therapy outperformed bispecific antibody in achieving higher CR rates, although with an increase in severe adverse events.

Since non-anthracycline-based chemotherapy with L-asparaginase has improved survival outcomes in patients with extranodal natural killer/T-cell lymphoma (ENKTL), the incidence of central nerve system (CNS) relapse can be different when compared with previous reports. In this research, we sought to identify the incidence of and predictors for CNS relapse and to evaluate the necessity of CNS prophylaxis with intermediate-dose MTX (ID-MTX). The records of 399 patients in the training cohort and 253 patients in the validation cohort with ENKTL who received non-anthracycline-based chemotherapy were reviewed. Patients were divided into two groups according to whether the chemotherapy regimen included ID-MTX above 2 g/m². A new CNS-PINK model was developed using one-point powerful predictors of CNS relapse [the prognostic index of natural killer lymphoma (PINK); HR: 2.908; P = .030 and extranodal involvement (≥ 2); HR: 4.161; P = .001] and was calculated as a sum of scores. The high-risk group of CNS-PINK was defined as 2 points. The cumulative incidence of CNS relapse was different between the CNS-PINK risk groups in the training (P < .001) and validation cohort (P = .038). Patients in the high-risk CNS-PINK group who received SMILE or SMILE-like regimens with ID-MTX (S-ID-MTX) displayed a lower incidence rate of CNS relapse than did those who received other regimens without ID-MTX in the training cohort (P = .029). The CNS-PINK was demonstrated its strong predictability of CNS relapse in ENKTL patients. The effect of S-ID-MTX for preventing CNS events in high-risk CNS-PINK patients should be verified by future studies.

Purpose Plasma circulating tumor DNA (ctDNA) could reflect the genetic alterations present in tumor tissues. However, there is little information about the clinical relevance of cell-free DNA genotyping in peripheral T-cell lymphoma (PTCL).Materials and Methods After targeted sequencing plasma cell-free DNA of patients with various subtypes of PTCL (n=94), we analyzed the mutation profiles of plasma ctDNA samples and their predictive value of dynamic ctDNA monitoring for treatment outcomes.Results Plasma ctDNA mutations were detected in 53 patients (56%, 53/94), and the detection rate of somatic mutations was highest in angioimmunoblastic T-cell lymphoma (24/31, 77%) and PTCL, not otherwise specified (18/29, 62.1%). Somatic mutations were detected in 51 of 66 genes that were sequenced, including the following top 10 ranked genes: RHOA, CREBBP, KMT2D, TP53, IDH2, ALK, MEF2B, SOCS1, CARD11, and KRAS. In the longitudinal assessment of ctDNA mutation, the difference in ctDNA mutation volume after treatment showed a significant correlation with disease relapse or progression. Thus, a ≥ 1.5-log decrease in genome equivalent (GE) between baseline and the end of treatment showed a significant association with better survival outcomes than a < 1.5-log decrease in GE.Conclusion Our results suggest the clinical relevance of plasma ctDNA analysis in patients with PTCL. However, our findings should be validated by a subsequent study with a larger study population and using a broader gene panel.

Seok Jin Kim, M.D., Ph.D., Sang Eun Yoon, M.D., Ph.D., and Won Seog Kim, M.D., Ph.D.. Ann Lab Med 2024;44:210-21. https://doi.org/10.3343/alm.2023.0388

Variances in global access to drugs and treatment practices make it challenging to understand the benefit of contemporary therapies in patients with relapsed and refractory (R/R) mature T-cell and natural killer–cell lymphomas (MTCL and MNKCL). We conducted an international retrospective cohort study of 925 patients with R/R MTCL and MNKCL. In peripheral T-cell lymphoma–not otherwise specified and anaplastic lymphoma kinase–negative anaplastic large cell lymphoma (ALK– ALCL), patients with relapsed lymphoma demonstrated a superior median overall survival (OS) relative to refractory from the time of second-line treatment. We identified several independent predictors of OS for R/R lymphoma including age >60 years, primary refractory disease, histological subtype other than angioimmunoblastic T-cell lymphoma (AITL), extranodal sites >1, Ki67 ≥40%, and absolute lymphocyte count less than the lower limit of normal. A multivariable model incorporating these formed the basis for a prognostic index for R/R TCL, in which patients are stratified into low-risk (0-1 risk factor), intermediate-risk (2-3 risk factors), or high-risk (≥4 risk factors) groups, which were associated with 3-year OS of 57.14%, 23.3%, and 7%, respectively. Patients received either a "novel" single agent (SA; 35%) or cytotoxic chemotherapy (CC; 60%) for their second-line treatment. Higher progression-free survival was observed with SA over CC for the entire cohort with a higher 3-year OS in AITL and ALK– ALCL. Among the SA, small-molecule inhibitors demonstrated OS advantage relative to CC in AITL. Our results highlight continued efficacy of novel drugs globally and the potential of a new prediction model in informing heterogeneous prognosis within the R/R population of MTCL and MNKCL.