Scott, David W.

Abstract Serum soluble chemokines/cytokines produced by Hodgkin cells and the tumor microenvironment might be of value as biomarkers in classic Hodgkin lymphoma (cHL). We assessed serum thymus and activation-related chemokine (TARC), macrophage-derived chemokine (MDC), interleukin-10 (IL-10), and soluble CD163 (sCD163) levels at baseline, time of interim fluorodeoxyglucose positron emission tomography (PET), and after therapy in cHL patients treated on S0816, an intergroup phase 2 response-adapted study evaluating escalated therapy for interim PET (PET2)–positive patients (www.clinicaltrials.gov #NCT00822120). Epstein-Barr virus (EBV) status was assessed, and 559 serum samples were evaluated for TARC, MDC, IL-10, and sCD163 by immunoassay. EBV positivity correlated with higher sCD163 and IL-10 levels but lower TARC levels. While baseline biomarker levels were not associated with outcome, sCD163 levels at the time of PET2 were associated with favorable progression-free survival (PFS), adjusting for PET2 status. After therapy TARC, MDC, and IL-10 correlated with PFS and overall survival (OS) on univariable analysis, which remained significant adjusting for international prognostic score. When also adjusting for end-of-therapy PET results, TARC and IL-10 remained significantly associated with shorter PFS and OS. Exploratory analysis in PET2-negative patients showed that elevated posttherapy TARC and IL-10 levels were associated with PFS. Serum cytokine levels correlate with outcome in cHL and should be investigated further in risk-adapted cHL trials.

Abstract Primary mediastinal large B-cell lymphoma (PMBCL) is recognized as a distinct entity in the World Health Organization classification. Currently, the diagnosis relies on consensus of histopathology, clinical variables, and presentation, giving rise to diagnostic inaccuracy in routine practice. Previous studies have demonstrated that PMBCL can be distinguished from subtypes of diffuse large B-cell lymphoma (DLBCL) based on gene expression signatures. However, requirement of fresh-frozen biopsy material has precluded the transfer of gene expression–based assays to the clinic. Here, we developed a robust and accurate molecular classification assay (Lymph3Cx) for the distinction of PMBCL from DLBCL subtypes based on gene expression measurements in formalin-fixed, paraffin-embedded tissue. A probabilistic model accounting for classification error, comprising 58 gene features, was trained on 68 cases of PMBCL and DLBCL. Performance of the model was subsequently evaluated in an independent validation cohort of 158 cases and showed high agreement of the Lymph3Cx molecular classification with the clinicopathological diagnosis of an expert panel (frank misclassification rate, 3.8%). Furthermore, we demonstrate reproducibility of the assay with 100% concordance of subtype assignments at 2 independent laboratories. Future studies will determine Lymph3Cx’s utility for routine diagnostic purposes and therapeutic decision making.

7547 Background: E1412 statistical design is based on results of lenalidomide/RCHOP (R2CHOP) vs RCHOP in ABC-DLBCL as determined by NanoString gene expression profiling (GEP). Central pathology review (CPR) was conducted to confirm diagnosis and to ensure adequate tissue for GEP. Initially, CPR occurred after randomization and treatment initiation. Due to high ineligibility rate (IR), the protocol was amended to include real-time CPR to determine patient eligibility prior to study enrollment. We describe the revision and how it affected the IR. Methods: Pre-amendment, CPR was done retrospectively. Post-amendment, CPR was done prior to enrollment, in real time, on a submitted tissue block, H&E, and CD20 slides. Based on CPR, if a diagnosis of DLBCL was confirmed, and sufficient tissue remained for GEP, a patient was deemed eligible and the submitter was notified by fax. Protocol goal was notification within 2 working days (WD) of receipt of materials at the CPR site. Results: Pre-amendment, 219 patients were enrolled. Material was typically received at the CPR site 6-9 months after patient registration. The IR with CPR was 36% for all those enrolled, and 26% for patients with adequate tissue for GEP. Post-amendment, 218 patients were submitted for CPR: 145 (67%) were eligible; 73 (33%) were ineligible. Reasons for ineligibility included insufficient tissue (n=27) or a diagnosis other than de novo DLBCL (n=46). Notification of eligibility occurred in a median of 2 WD (Mean 2 WD; Range 1-5 WD). 90% were notified within the protocol goal of 2 WD. GEP for all enrolled was completed within 6 weeks of CPR. Conclusions: The success of this novel, real-time CPR serves as a model for the future of NCTN DLBCL trials. When CPR is performed rapidly prior to enrollment, study slots may more accurately reflect the target population and eliminate excess costs. In the precision medicine era, rapid collection of relevant pathology and biomarker data is essential to trial success. Study Coordinated by ECOG-ACRIN Cancer Research Group (Robert L. Comis, MD and Mitchell D. Schnall, MD, PhD, Group Co-Chairs), supported by NCI grant # CA180820, CA180794, CA180790, CA180799, CA180833.

SummaryMantle cell lymphoma (MCL) is still considered incurable and the course of the disease is highly variable. Established risk factors include the Mantle Cell Lymphoma International Prognostic Index (MIPI) and the quantification of the proliferation rate of the tumour cells, e.g. by Ki‐67 immunohistochemistry. In this study, we aimed to validate the prognostic value of the gene expression‐based MCL35 proliferation assay in patient cohorts from randomized trials of the European Mantle Cell Lymphoma Network. Using this assay, we analysed the gene expression proliferation signature in routine diagnostic lymph node specimens from MCL Younger and MCL Elderly trial patients, and the calculated MCL35 score was used to assign MCL patients to low (61%), standard (27%) or high (12%) risk groups with significantly different outcomes. We confirm here in our prospective clinical trial cohort of MCL patients, that the MCL35 assay is strongly prognostic, providing additional information to the Ki‐67 index and the MIPI. Thus, this robust assay may assist in making treatment decisions or in devising risk‐adapted prospective clinical trials in the future.

SummaryPatients with mantle cell lymphoma (MCL) generally have a dismal prognosis. Intensified induction treatment with rituximab and high dose cytarabine (R_HDAC), and consolidation with high‐dose therapy with autologous stem cell support has resulted in 10‐year overall survival (OS) higher than 60%. However, the clinical course varies. Diagnostic tools capable of stratifying patients include the MCL International Prognostic Index (MIPI), gene expression‐based proliferation signature, Ki‐67 proliferation index or tumour cell morphology. Here, we tested the performance of a newly developed Nanostring‐based RNA expression‐based proliferation assay (MCL35) on formalin‐fixed paraffin‐embedded tumour tissue from younger patients recruited in or treated according to Nordic MCL protocols compared to the prognosticators listed above. Seventy‐four patients were included and the assay performed well in all cases except four, which had inadequate RNA quality. The patients were evenly distributed in the MCL35 low‐, intermediate‐ and high‐risk categories. MCL35 low‐ and intermediate‐ risk groups had overlapping progression‐free survival (PFS), while patients in the high‐risk category had significantly inferior PFS. Combining MCL35 with MIPI or the MIPI‐C (MIPI with the addition of binary Ki67 score +/−30%) showed a better discrimination than either assessment alone. In conclusion, the MCL35 assay alone or combined with MIPI or MIPI‐C scores can identify patients who still have a dismal outcome despite intensified treatment.

Key PointsA new molecular assay identifies conventional and leukemic nonnodal MCL with differing clinicobiological features. The integration of the novel assay with genetic alterations identifies subsets of MCL patients with different management and outcome.

Key Points HGBL-DH/TH makes up 8% of de novo DLBCL, with HGBL-DH/TH with BCL2 rearrangement being a GCB phenomenon. Restricting FISH testing to tumors with dual protein expression and GCB subtype results in testing <15% of tumors, but missing ∼35% of HGBL-DH/TH.