Citations

SummaryHistological transformation (HT) of follicular lymphoma (FL) to an aggressive lymphoma after chemotherapy remains a key issue. The incidence of HT after radioimmunotherapy (RIT) is unknown. This single institution study analysed the risk of HT in FL after treatment with yttrium‐90 ibritumomab tiuxetan in 115 consecutive patients treated during 1987–2012. RIT was administered for progressive FL in 111 (97%) patients and as first‐line therapy in the remaining 4. 28% (n = 32) had HT, occurring at a median of 60 months from diagnosis and 20 months after RIT. 48% (12/25) of patients who received fludarabine developed HT. The estimated 10‐year risk of HT in the fludarabine and non‐fludarabine groups was 67% and 26% respectively (P = 0·015). Only prior fludarabine was significantly associated with predicting the risk of HT after RIT. 8% (9/115) of patients developed therapy‐related myelodysplastic syndrome/acute myeloid leukaemia (tMDS/AML) at a median of 41·4 months (range, 5–89). The estimated 10‐year risk of tMDS/AML in non‐fludarabine treated patients (n = 90) versus fludarabine treated (n = 25) was 13% and 29%, respectively. The estimated overall risk of FL undergoing HT at 10 years without fludarabine exposure appears similar to patients reported in the literature that have not received RIT. Patients with prior purine‐analogue therapy are at significantly higher risk of HT.

Key Points Pembrolizumab was first shown to be clinically active in CLL patients with RT. PD-1 and PD-L1 expression in tumor microenvironment are promising biomarkers to select RT patients for PD-1 blockade.

AbstractHigher ratios of the pre‐treatment peripheral blood absolute lymphocyte (ALC) to absolute monocyte counts (AMC) are associated with improved outcomes in lymphoma. Conversely, elevated pre‐treatment serum cytokines are associated with inferior outcomes. The relationship between pre‐treatment serum cytokines and ALC/AMC ratios remains unknown. We studied twelve serum cytokines and the ALC/AMC ratios in 390 patients with untreated diffuse large B‐cell, follicular, mantle cell, T‐cell, and Hodgkin lymphoma. Different pre‐treatment serum cytokine concentrations correlated with ALC, AMC, and ALC/AMC ratios depending on the lymphoma type. In the entire cohort (n = 390) lower ALC/AMC ratios modestly correlated with higher IL‐2R (r = −0.36), IL‐12 (r = −0.17), IP‐10 (r = −0.23), and MIG (r = −0.32) concentrations (p < 0.001). Elevated IL‐2R was independently associated with suppressed ALC (OR 2.69, 95% CI 1.77–4.07,p < 0.001), elevated AMC (OR 2.05, 95% CI 1.34–3.14,p < 0.001), and suppressed ALC/AMC ratios (OR 3.51, 95% CI 2.31–5.34,p < 0.001). Both elevated IL‐2R (HR 2.27, 95% CI 1.48–3.49,p < 0.001) and suppressed ALC/AMC ratios (HR 1.53, 95% CI 1.03–2.28,p = 0.037) were independently associated with inferior overall survival. These data support the notion that elevated serum cytokines are immunosuppressive and provide further rationale to target the tumor microenvironment for therapeutic benefit.

Abstract Purpose: Randomized, multicenter, open-label, phase 2/3 trial investigating lenalidomide versus investigator's choice (IC) in relapsed/refractory diffuse large B-cell lymphoma (DLBCL). Experimental Design: Patients with DLBCL who received ≥2 prior therapies were stratified by DLBCL subtype [germinal center B-cell (GCB) vs. non-GCB; determined by immunohistochemistry (IHC)] and then randomized 1:1 to lenalidomide (25 mg/day, 21 days of 28-day cycle) or IC (gemcitabine, rituximab, etoposide, or oxaliplatin). Crossover to lenalidomide was permitted for IC-treated patients with radiologically confirmed progressive disease. The primary endpoint was overall response rate (ORR). Progression-free survival (PFS), overall survival, and subtype analysis [GCB vs. activated B-cell (ABC)] using gene expression profiling (GEP) were exploratory endpoints. Results: Stage 1: 102 DLBCL patients (by IHC: non-GCB, n = 54; GCB, n = 48) received ≥1 dose of lenalidomide or IC. Hematologic treatment-emergent adverse events with lenalidomide versus IC included neutropenia (42.6%; 36.4%), anemia (33.3%; 47.3%), thrombocytopenia (24.1%; 43.6%), and leukopenia (5.6%; 12.7%), respectively. Overall, lenalidomide-treated patients had an ORR of 27.5% versus 11.8% in IC (ORRs were similar regardless of IHC-defined DLBCL subtype). Median PFS was increased in patients receiving lenalidomide (13.6 weeks) versus IC (7.9 weeks; P = 0.041), with greater improvements in non-GCB patients (15.1 vs. 7.1 weeks, respectively; P = 0.021) compared with GCB (10.1 vs. 9.0 weeks, respectively; P = 0.550). Conclusions: The clinical benefit of lenalidomide monotherapy in DLBCL patients was more evident in the non-GCB subtype. Exploratory analyses suggest that this preferential benefit was more pronounced in the GEP-defined ABC population, demonstrating a need for additional studies of lenalidomide in DLBCL using GEP subtyping. Clin Cancer Res; 23(15); 4127–37. ©2017 AACR.