Citations

Abstract Purpose: Only a limited number of genetic studies have been conducted in primary central nervous system lymphomas (PCNSL), partly due to the rarity of the tumors and the very limited amount of available tissue. In this report, we present the first molecular characterization of copy number abnormalities (CNA) of newly diagnosed PCNSL by array-based comparative genomic hybridization (aCGH) in formalin-fixed paraffin-embedded (FFPE) specimens and compare the results with matched, frozen tumor specimens. Experimental Design: We conducted aCGH in FFPE tissues from PCNSL. Results were compared with matched, paired, frozen tumors. Results: Our analysis confirmed the good to fair quality and reliability of the data generated from limited amounts of tumoral FFPE tissue. Overall, all PCNSL cases were characterized by highly complex karyotypes, with a median of 23 CNAs per patient (range, 17–47). Overall, 20 chromosomal regions were recurrently found in more than 40% of cases. Deletions of 6p21, 6q, and 9p21.3 and gain of 12q12-q24.33 were the commonest CNAs. Other minimal affected regions were defined, and novel recurrent CNAs affecting single genes were identified in 3q26.32 (TBL1XR1) and 8q12.1 (TOX). Conclusions: The results obtained are encouraging. Larger archival tissue collections can now be analyzed to complement the still fragmented knowledge we have of the genetic basis of the PCNSL. Clin Cancer Res; 17(13); 4245–53. ©2011 AACR.

Abstract Two patients who had focal neurological deficits as the initial manifestation of a malignant non-Hodgkin's lymphoma involving the skull are described. Soft-tissue masses and variable bone destruction were the predominant computed tomographic findings, and magnetic resonance imaging studies revealed meningeal involvement in one case and sinus thrombosis in the other. Malignant non-Hodgkin's lymphomas initially appearing in the skull are rare, but these lesions should be considered in patients with a palpable scalp mass who have focal neurological signs.

Os linfomas primários do SNC são raros, mas sua incidência tem aumentado nos últimos anos, Estes tumores frequentemente se localizam nos gânglios da base e tálamo ou se apresentam de forma multifocal. O tratamento atual para eles é a radioterapia, associada ou não a quimioterapia. Devido à sua extremamente baixa morbidade, a biópsia estereo-táxica é o método ideal para determinar o diagnóstico histológico em pacientes com suspeita de linfomas do SNC. Os autores apresentam estudo de 49 casos de linfomas primários do SNC, diagnosticado por biópsia estereotáxica.

Abstract Introduction. PCNSL is an aggressive primary brain tumor characterized by a perivascular accumulation of malignant cells that have lymphoid characteristics. As there is significantly less information regarding the molecular pathogenesis of PCNSL in comparison with systemic lymphomas the aim of this study was to perform a comprehensive high-resolution genomic analysis in a cohort of PCNSL cases to better characterize the disease at chromosomal and gene level. Material and Methods. Specimens from 7 EBV- and HIV-negative and presumed immunocompetent PCNSL patients with sufficient frozen tissue for DNA extraction were studied. Copy-number abnormalities were analyzed by array CGH using SurePrint G3 (1 million probes) microarray (Agilent). B-cell differentiation status was characterized by immunostains for CD10, MUM-1, and CD138. Results. PCNSL cases were characterized by highly complex genomes with a median of 23 copy-number abnormalities per patient (range 16-49). Twenty-four chromosomal regions were affected in recurrent deletions and 19 in copy-number gains. Gain of 12q12-q24.33 and losses of 9p21.3 and 6q were the most common abnormalities, found in five of the seven patients. There was not a deleted region on 6q unique to all cases, with 6q14.1-q14.3, 6q16.3-q22.2 and 6q25.3-q26 losses being found in 4 out of 5 cases with 6q deletions. Two regions of interest were biallelically deleted. CDKN2A was the sole gene included in all cases with 9p21.3, being biallelically deleted in two out of 5 cases. TOX and CD58, genes associated with the development and activation of T cells, were also biallelically affected. Focal monoallelic deletions affecting negative regulators of the NFkB signaling pathway (MAP4K1, TANK, TAX1BP1, TRIB3), cell cycle (RB1) and immune-cell regulation (SIRPB1, CBLB, NFATC2) were also identified. Overall, a total of 22 genes were included in homozygous deletions in at least one case. Several chromosomal breakpoints were identified inside genes that encode transcription factors previously identified as being part of fusion protein in other hematological malignancies (FOXP1, ETV6 and NCOA2). Conclusion. This pilot study showed evidence for a highly complex genome, mainly characterized by abnormalities affecting a plethora of genes involved in lymphocyte development, activation and NF-kB signaling pathways regulation. Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 331.

Abstract Patients with glioblastoma (GBM) exhibit profound systemic immune defects that affect the success of traditional and immune-based treatments. A better understanding of the contribution of the tumor and therapy on systemic and local immune suppression is necessary to improve immune based therapies and monitor the effects of conventional and novel therapies. To identify possible sources of immunosuppression, we measured the constituents of circulating immunity in newly diagnosed and recurrent GBM patients with or without dexamethasone treatment. We identified dexamethasone dependent and independent changes in systemic immunity associated with GBM. Of note, we identified a profound lymphopenia associated with dexamethasone treatement that manifested itself in the T cell compartment with targeted effects on the CD4+ T cells. In addition, we identified tumor and dexamethasone dependent altered monocyte phenotypes. The major population of altered monocytes (CD14+HLA-DRlo/neg) inhibited T cell proliferation, was unable to fully differentiate into mature dendritic cells, was associated with dexamethasone-mediated changes in CCL2 levels, and could be re-created in vitro using tumor supernatants. Interestingly, CD14+HLA-DRlo/neg monocytes were elevated similarly in newly diagnosed and recurrent patients. These data demonstrate that both tumor and steroids contribute to systemic immunosuppression. We provide evidence that tumors express high levels of the monocyte recruitment chemokine CCL2, can contain high numbers of CD14+ cells, that tumor supernatants can transform CD14+HLA-DR+ cells into CD14+HLA-DRlo/neg immune suppressors, and that dexamethasone reduces CCL2 in vitro and is correlated with reduction of CCL2 in vivo. Consequently, we have developed a model for tumor mediated systemic immune suppression via recruitment and transformation of CD14+ cells. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5303.

Abstract Purpose: To describe the demographic and clinical features and outcomes for children and adolescents with primary CNS lymphoma (PCNSL). Experimental Design: A retrospective series of children and adolescents with PCNSL was assembled from 10 cancer centers in 3 countries. Results: Twenty-nine patients with a median age of 14 years were identified. Sixteen (55%) had Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 1 or greater. Frontline therapy consisted of chemotherapy only in 20 patients (69%), while 9 (31%) had chemotherapy plus cranial radiotherapy. Most patients received methotrexate (MTX)-based regimens. Overall response rate was 86% (complete remission 69%, partial remission 17%). The 2-year progression-free survival (PFS) and overall survival (OS) rates were 61% and 86%, respectively; the 3-year OS was 82%. Univariate analyses were conducted for age (≤14 vs. >14 years), PS (0 or 1 vs. >1), deep brain lesions, MTX dose, primary treatment with chemotherapy alone, intrathecal chemotherapy, and high-dose therapy. Primary treatment with chemotherapy alone was associated with better overall response rates with an odds ratio (OR) of 0.125 (P = 0.02). There was a marginally significant relationship between higher doses of MTX and response (OR = 1.5, P = 0.06). ECOG-PS of 0 to 1 was the only factor associated with better outcome with hazard ratios of 0.136 (P = 0.017) and 0.073 (P = 0.033) for PFS and OS, respectively. Conclusion: This is the largest series collected of pediatric PCNSL. The outcome of children and adolescents seems to be better than in adults. PS of 0 to 1 is associated with better survival. Clin Cancer Res; 17(2); 346–52. ©2011 AACR.

Purpose Primary CNS lymphoma (PCNSL) is an aggressive lymphoma but clinically validated biologic markers that can predict natural history to tailor treatment according to risk are lacking. Several genetic changes including BCL6 rearrangements and deletion of 6q22, containing the putative tumor suppressor gene PTPRK, are potential risk predictors. Herein we determined the prevalence and survival impact of del(6)(q22) and BCL6, immunoglobulin heavy chain (IGH), and MYC gene rearrangements in a large PCNSL cohort treated in a single center. Patients and Methods Interphase fluorescence in situ hybridization was performed using two-color probes for BCL6, MYC, IGH-BCL6, and del(6)(q22) on thin sections of 75 paraffin-embedded samples from 75 HIV-negative, immunocompetent patients newly diagnosed with PCNSL. Survival data were analyzed using Kaplan-Meier survival curves, log-rank tests, and proportional hazards regression adjusting for age, deep structure involvement, and high-dose methotrexate (HDMTX) treatment. Results The prevalence of del(6)(q22) and BCL6, IGH, and MYC translocations was 45%,17%, 13%, and 3%, respectively. The presence of del(6)(q22) and/or a BCL6 translocation was associated with inferior overall survival (OS; P = .0097). The presence of either del(6)(q22) alone or a BCL6 translocation alone was also associated with inferior OS (P = .0087). Univariable results held after adjusting for age, deep structure involvement, and HDMTX. Conclusion Del (6)(q22) and BCL6 rearrangements are common in PCNSL and predict for decreased OS independent of deep structure involvement and HDMTX. Unlike systemic diffuse large B-cell lymphoma, del(6)(q22) is common and IGH translocations are infrequent and usually involve BCL6 rather than BCL2, suggesting a distinct pathogenesis.

Abstract Primary central nervous system (CNS) lymphoma (PCNSL) is a diffuse large B-cell lymphoma (DLBCL) confined to the CNS. A genome-wide gene expression comparison between PCNSL and non-CNS DLBCL was performed, the latter consisting of both nodal and extranodal DLBCL (nDLBCL and enDLBCL), to identify a “CNS signature.” Pathway analysis with the program SigPathway revealed that PCNSL is characterized notably by significant differential expression of multiple extracellular matrix (ECM) and adhesion-related pathways. The most significantly up-regulated gene is the ECM-related osteopontin (SPP1). Expression at the protein level of ECM-related SPP1 and CHI3L1 in PCNSL cells was demonstrated by immunohistochemistry. The alterations in gene expression can be interpreted within several biologic contexts with implications for PCNSL, including CNS tropism (ECM and adhesion-related pathways, SPP1, DDR1), B-cell migration (CXCL13, SPP1), activated B-cell subtype (MUM1), lymphoproliferation (SPP1, TCL1A, CHI3L1), aggressive clinical behavior (SPP1, CHI3L1, MUM1), and aggressive metastatic cancer phenotype (SPP1, CHI3L1). The gene expression signature discovered in our study may represent a true “CNS signature” because we contrasted PCNSL with wide-spectrum non-CNS DLBCL on a genomic scale and performed an in-depth bioinformatic analysis.