Rimsza, Lisa M.

AbstractThe investigators present results on the long-term value and limitations of early interim positron emission tomography (PET) scanning in advanced Hodgkin lymphoma.

Diffuse large B‐cell lymphoma (DLBCL) is up to 17‐fold more likely to occur, follows a more aggressive clinical course and frequently presents at advanced stages in HIV infected (+) individuals compared to HIV negative (−) individuals. However, the molecular pathology underpinning the clinical features of DLBCL in HIV(+) patients relative to the general population is poorly understood. We performed a retrospective study examining the transcriptional, genomic and protein expression differences between HIV(+) and HIV(−) germinal center B‐cell (GCB) DLBCL cases using digital gene expression analysis, array comparative genomic hybridization (CGH) and immunohistochemistry (IHC). Genes associated with cell cycle progression ( CCNA2 , CCNB1 , CDC25A , E2F1 ), DNA replication ( MCM2 , MCM4 , MCM7 ) and DNA damage repair, including eight Fanconi anemia genes ( FANCA , FANCD1/BRCA2 , FANCE , FANCG , FANCR/RAD51 , FANCS/BRCA1 , FANCT/UBE2T , FANCV/MAD2L2 ), were significantly increased in HIV(+) GCB‐DLBCL tumors compared to HIV(−) tumors. In contrast, genes associated with cell cycle inhibition ( CDKN1A , CDKN1B ) as well as apoptosis regulating BCL2 family members ( BCL2 , BAX , BIM , BMF , PUMA ) were significantly decreased in the HIV(+) cohort. BCL2 IHC confirmed this expression. Array CGH data revealed that HIV(+) GCB‐DLBCL tumors have fewer copy number variations than their HIV(−) counterparts, indicating enhanced genomic stability. Together, the results show that HIV(+) GCB‐DLBCL is a distinct molecular malignancy from HIV(−) GCB‐DLBCL; with an increased proliferative capacity, confirmed by Ki67 IHC staining, and enhanced genomic stability, the latter of which is likely related to the enhanced expression of DNA repair genes.

Tissue microarrays (TMAs) are important tools to conserve precious tissue resources from increasingly smaller biopsies and to control experimental costs and variation across sample sets. The quality assurance assessment of TMA materials created at centralized biobanks has not been standardized. Herein, we outline 2 processes for the construction of TMAs (“recipient block” and “tape” methods) and the associated preconstruction quality control measures (pathology review, protein and RNA assessment, map creation, and storage conditions) developed by the AIDS Cancer Specimen Resource (ACSR) Network’s Science and Technology Core. These steps provide a suggested framework for quality assessment that allows end-users, receiving materials from tissue banks, confidence in their experimental results.

Abstract The growing body of genomic information collected and applied to mature aggressive B-cell lymphoma diagnosis and management has exploded over the last few years due to improved technologies with high-throughput capacity, suitable for use on routine formalin-fixed, paraffin-embedded tissue biopsies, and decreasing costs. These techniques have made evaluation of complete DNA sequences, RNA-expression patterns, translocations, copy-number alterations, loss of heterozygosity, and DNA-methylation patterns possible on a genome-wide level. This chapter will present a case of aggressive B-cell lymphoma and discuss the most important genomic abnormalities that characterize this group of entities in the recent update to the fourth edition of the World Health Organization (WHO) lymphoma classification system. Genomic abnormalities discussed will include those necessary for certain diagnoses such as translocations of MYC, BCL2, or BCL6; gene-expression-profiling categorization; the newly defined Burkitt-like lymphoma with 11q abnormalities; prognostic and predictive mutations, as well as tumor heterogeneity. Finally, our current practices for clinical triage of specimens with a potential diagnosis of aggressive B-cell lymphomas are also described. Options for treatment at relapse, in light of these genomic features, will be discussed in the third presentation from this session.

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 Although recent advances in molecular genetics have enabled improved risk classification of follicular lymphoma (FL) using, for example, the m7-FLIPI score, the impact on treatment has been limited. We aimed to assess the prognostic significance of copy-number aberrations (CNAs) and copy-neutral loss of heterozygosity (cnLOH) identified by chromosome genomic-array testing (CGAT) at FL diagnosis using prospectively collected clinical trial specimens from 255 patients enrolled in the SWOG study S0016. The impact of genomic aberrations was assessed for early progression (progressed or died within 2 years after registration), progression-free survival (PFS), and overall survival (OS). We showed that increased genomic complexity (ie, the total number of aberration calls) was associated with poor outcome in FL. Certain chromosome arms were critical for clinical outcome. Prognostic CNAs/cnLOH were identified: whereas early progression was correlated with 2p gain (P = .007; odds ratio [OR] = 2.55 [1.29, 5.03]) and 2p cnLOH (P = .005; OR = 10.9 [2.08, 57.2]), 2p gain specifically encompassing VRK2 and FANCL predicted PFS (P = .01; hazard ratio = 1.80 [1.14, 2.68]) as well as OS (P = .005; 2.40 [1.30, 4.40]); CDKN2A/B (9p) deletion correlated with worse PFS (P = .004, 3.50 [1.51, 8.28]); whereas CREBBP (16p) (P < .001; 6.70 [2.52, 17.58]) and TP53 (17p) (P < .001; 3.90 [1.85, 8.31]) deletion predicted worse OS. An independent cohort from the m7-FLIPI study was explored, and the prognostic significance of aberration count, and TP53 and CDKN2A/B deletion were further validated. In conclusion, assessing genomic aberrations at FL diagnosis with CGAT improves risk stratification independent of known clinical parameters, and provides a framework for development of future rational targeted therapies.