Gene expression profiling impacts treatment decision making in newly diagnosed multiple myeloma patients in the prospective PROMMIS trial.

Multiple myeloma (MM) is a heterogeneous hematologic malignancy associated with several risk factors including genetic aberrations which impact disease response and survival. Thorough risk classification is essential to select the best clinical strategy to optimize outcomes. The SKY92 molecular signature classifies patients as standard- or high-risk for progression. The PRospective Observational Multiple Myeloma Impact Study (PROMMIS; NCT02911571) measures impact of SKY92 on risk classification and treatment plan. Newly diagnosed MM patients had bone marrow aspirates analyzed for SKY92. Physicians completed a questionnaire for each patient capturing risk classification, hypothetical treatment plan, and physician confidence in the treatment plan, before and after unblinding SKY92. One hundred forty seven MM patients were enrolled. Before unblinding SKY92, physicians regarded 74 (50%) patients as clinical standard-risk. After unblinding SKY92, 16 patients were re-assigned as high-risk by the physician, and for 15 of them treatment strategy was impacted, resulting in an escalated treatment plan. For the 73 (50%) clinical high-risk patients, SKY92 indicated 46 patients to be standard-risk; for 31 of these patients the treatment strategy was impacted consistent with a de-escalation of risk. Overall, SKY92 impacted treatment decisions in 37% of patients (p < 0.001). For clinical decision-making, physicians incorporated SKY92, and the final assigned clinical risk was in line with SKY92 for 89% of patients. Furthermore, SKY92 significantly increased the confidence of the physicians' treatment decisions (p < 0.001). This study shows potential added value of SKY92 in MM for treatment decision making.

STAG2 Is a Biomarker for Prediction of Recurrence and Progression in Papillary Non-Muscle-Invasive Bladder Cancer.

Purpose: Most bladder cancers are early-stage tumors known as papillary non-muscle-invasive bladder cancer (NMIBC). After resection, up to 70% of NMIBCs recur locally, and up to 20% of these recurrences progress to muscle invasion. There is an unmet need for additional biomarkers for stratifying tumors based on their risk of recurrence and progression. We previously identified STAG2 as among the most commonly mutated genes in NMIBC and provided initial evidence in a pilot cohort that STAG2-mutant tumors recurred less frequently than STAG2 wild-type tumors. Here, we report a STAG2 biomarker validation study using two independent cohorts of clinically annotated papillary NMIBC tumors from the United States and Europe.Experimental Design: The value of STAG2 immunostaining for prediction of recurrence was initially evaluated in a cohort of 82 patients with papillary NMIBC ("Georgetown cohort"). Next, the value of STAG2 immunostaining for prediction of progression to muscle invasion was evaluated in a progressor-enriched cohort of 253 patients with papillary NMIBC ("Aarhus cohort").Results: In the Georgetown cohort, 52% of NMIBC tumors with intact STAG2 expression recurred, whereas 25% of STAG2-deficient tumors recurred (P = 0.02). Multivariable analysis identified intact STAG2 expression as an independent predictor of recurrence (HR = 2.4; P = 0.05). In the progressor-enriched Aarhus cohort, 38% of tumors with intact STAG2 expression progressed within 5 years, versus 16% of STAG2-deficient tumors (P < 0.01). Multivariable analysis identified intact STAG2 expression as an independent predictor of progression (HR = 1.86; P = 0.05).Conclusions: STAG2 IHC is a simple, binary, new assay for risk stratification in papillary NMIBC. Clin Cancer Res; 24(17); 4145-53. ©2018 AACR.

Pediatric Hodgkin lymphoma: biomarkers, drugs, and clinical trials for translational science and medicine.

Hodgkin lymphoma (HL) is a lymphoid malignancy that is typically derived from germinal-center B cells. EBV infection, mutations in NF-κB pathway genes, and genetic susceptibility are known risk factors for developing HL. CD30 and NF-κB have been identified as potential biomarkers in pediatric HL patients, and these molecules may represent therapeutic targets. Although current risk adapted and response based treatment approaches yield overall survival rates of >95%, treatment of relapse or refractory patients remains challenging. Targeted HL therapy with the antibody-drug conjugate Brentuximab vedotin (Bv) has proven to be superior to conventional salvage chemotherapy and clinical trials are being conducted to incorporate Bv into frontline therapy that substitutes Bv for alkylating agents to minimize secondary malignancies. The appearance of secondary malignancies has been a concern in pediatric HL, as these patients are at highest risk among all childhood cancer survivors. The risk of developing secondary leukemia following childhood HL treatment is 10.4 to 174.8 times greater than the risk in the general pediatric population and the prognosis is significantly poorer than the other hematological malignancies with a mortality rate of nearly 100%. Therefore, identifying clinically valuable biomarkers is of utmost importance to stratify and select patients who may or may not need intensive regimens to maintain optimal balance between maximal survival rates and averting late effects. Here we discuss epidemiology, risk factors, staging, molecular and genetic prognostic biomarkers, treatment for low and high-risk patients, and the late occurrence of secondary malignancies in pediatric HL.

An Immunohistochemical Survey of SNARE Proteins Shows Distinct Patterns of Expression in Hematolymphoid Neoplasia.

OBJECTIVES: Five proteins from the soluble N-ethylmaleimide-sensitive factor activating protein receptor (SNARE) complex family were studied in normal hematopoietic cells in bone marrow; normal lymphocytes at different stages of maturation and differentiation in bone marrow, thymus, tonsil, and lymph node; malignant lymphomas; and leukemias. METHODS: Sixty-eight reactive and 380 hematopoietic and lymphoid neoplasms were immunohistochemically stained for syntaxin 7 (STX7), vesicle-associated membrane proteins (VAMP2, VAMP7, VAMP8), and synaptosomal-associated protein 23 (SNAP23). RESULTS: STX7 has potential for being a useful marker for distinguishing between normal B precursors (hematogones) vs B lymphoblasts, as well as between the "popcorn" cells of nodular lymphocyte-predominant Hodgkin lymphoma vs the Reed-Sternberg cells of classic Hodgkin lymphoma or the B cells of T-cell, histiocyte-rich B-cell lymphoma. VAMP2 is uniquely expressed by both reactive and malignant plasma cells, in contrast to B-cell non-Hodgkin lymphoma. There is differential expression of SNARE proteins in normal and neoplastic lymphoid tissue depending on lymphocyte maturation stage. CONCLUSIONS: Differential SNARE protein expression in the lymphoid system may have potential use in diagnosis and may offer clues to lymphoma biology. VAMP2 is a promising new plasma cell marker.

Clinical decision support systems for improving diagnostic accuracy and achieving precision medicine.

As research laboratories and clinics collaborate to achieve precision medicine, both communities are required to understand mandated electronic health/medical record (EHR/EMR) initiatives that will be fully implemented in all clinics in the United States by 2015. Stakeholders will need to evaluate current record keeping practices and optimize and standardize methodologies to capture nearly all information in digital format. Collaborative efforts from academic and industry sectors are crucial to achieving higher efficacy in patient care while minimizing costs. Currently existing digitized data and information are present in multiple formats and are largely unstructured. In the absence of a universally accepted management system, departments and institutions continue to generate silos of information. As a result, invaluable and newly discovered knowledge is difficult to access. To accelerate biomedical research and reduce healthcare costs, clinical and bioinformatics systems must employ common data elements to create structured annotation forms enabling laboratories and clinics to capture sharable data in real time. Conversion of these datasets to knowable information should be a routine institutionalized process. New scientific knowledge and clinical discoveries can be shared via integrated knowledge environments defined by flexible data models and extensive use of standards, ontologies, vocabularies, and thesauri. In the clinical setting, aggregated knowledge must be displayed in user-friendly formats so that physicians, non-technical laboratory personnel, nurses, data/research coordinators, and end-users can enter data, access information, and understand the output. The effort to connect astronomical numbers of data points, including '-omics'-based molecular data, individual genome sequences, experimental data, patient clinical phenotypes, and follow-up data is a monumental task. Roadblocks to this vision of integration and interoperability include ethical, legal, and logistical concerns. Ensuring data security and protection of patient rights while simultaneously facilitating standardization is paramount to maintaining public support. The capabilities of supercomputing need to be applied strategically. A standardized, methodological implementation must be applied to developed artificial intelligence systems with the ability to integrate data and information into clinically relevant knowledge. Ultimately, the integration of bioinformatics and clinical data in a clinical decision support system promises precision medicine and cost effective and personalized patient care.

Reduced-dose fludarabine, cyclophosphamide, and rituximab (FCR-Lite) plus lenalidomide, followed by lenalidomide consolidation/maintenance, in previously untreated chronic lymphocytic leukemia.

Fludarabine, cyclophosphamide, and rituximab (FCR) remains the standard of care for fit chronic lymphocytic leukemia (CLL) patients requiring first therapy. However, side effects can be significant, and patients with poor risk features have inferior outcomes. The purpose of this study was to evaluate reduced-dose FCR (FCR-Lite) plus lenalidomide (FCR(2) ) followed by lenalidomide maintenance as a strategy to shorten immunochemotherapy in untreated CLL. Patients received four to six cycles of FCR(2) . Patients who were minimal residual disease (MRD) negative in peripheral blood (PB) and bone marrow (BM) initiated 12 months of lenalidomide maintenance after either four or six cycles (based on MRD status). The primary study endpoint was the complete response (CR) rate after four cycles of FCR(2) . Twenty patients were evaluable. After four cycles of FCR(2) , response rates were: CR, 45.0%; CR with incomplete blood count recovery (CRi), 5.0%; partial response (PR), 45.0%; and stable disease (SD), 5.0%. BM and PB samples from 27.8% and 52.9% of patients, respectively, were MRD negative. After six cycles, response rates were: CR, 58.3%; CRi, 16.7%; and PR, 25.0%. BM and PB samples from 50.0% and 72.7% of patients, respectively, were MRD negative. Overall, 75% of evaluable patients achieved a CR or CRi following FCR(2) . After 17.4 months of median follow-up, one progression and one death occurred. Our findings suggest that FCR(2) combines encouraging clinical activity with acceptable toxicity in previously untreated CLL. Lenalidomide can be safely added to FCR and may reduce chemotherapy exposure without compromising outcomes.

Addition of lenalidomide to rituximab, ifosfamide, carboplatin, etoposide (RICER) in first-relapse/primary refractory diffuse large B-cell lymphoma.

Relapsed/refractory diffuse large B-cell lymphoma (DLBCL) is associated with a poor prognosis. Outcomes are particularly poor following immunochemotherapy failure or relapse within 12 months of induction. We conducted a Phase I/II trial of lenalidomide plus RICE (rituximab, ifosfamide, carboplatin, and etoposide) (RICER) as a salvage regimen for first-relapse or primary refractory DLBCL. Dose-escalated lenalidomide was combined with RICE every 14 d. After three cycles of RICER, patients with chemosensitive disease underwent stem cell collection and consolidation with BEAM [BCNU (carmustine), etoposide, cytarabine, melphalan] followed by autologous stem cell transplantation (autoSCT). Patients who recovered from autoSCT toxicities within 90 d initiated maintenance treatment with lenalidomide 25 mg daily for 21 d every 28 d for 12 months. No dose-limiting or unexpected toxicities occurred with lenalidomide 25 mg plus RICE. Grade 3/4 haematological toxicities resolved appropriately, and planned dose density and dose intensity of RICER were preserved. No lenalidomide or RICE dose reductions were required in any of the three cycles. After two cycles of RICER, nine of 15 patients (60%) achieved a complete response, and two achieved a partial response (13%). Combining lenalidomide with RICE is feasible, and results in promising response rates (particularly complete response rates) in high-risk DLBCL patients.

T-cell prolymphocytic leukemia with extensive cardiovascular infiltrate leading to multiple myocardial infarctions and cardiac death.

Lymphocytic neoplasm involving the heart is not common and usually presents with pericardial effusion or focal myocardial infiltration. Myocardial infarctions due to leukemic infiltration of the coronary arteries are rarely reported. We present the case of a 52-year-old Guatemalan man with a one-year history of untreated T-cell prolymphocytic leukemia. He was admitted to our hospital for chemotherapy and evaluation of a pulmonary cavitary lesion by wedge resection. During sedation, the patient experienced acute respiratory failure and hypovolemic shock, from which he could not be resuscitated. Autopsy revealed that leukemic cells extensively infiltrated the aorta, myocardium, and coronary arteries. The lumina of the 3 major coronary artery branches showed 70% to 95% stenosis, with multifocal remote myocardial infarctions. Tumor cells were also detected in the lungs and other organs. The acute cardiorespiratory insufficiency secondary to leukemia-particularly the extensive infiltration of the coronary arteries and myocardium, and the multiple myocardial infarctions-eventually resulted in cardiac death.

Occurrence of chronic lymphocytic leukemia in patients with chronic myelogenous leukemia.

Chronic lymphocytic leukemia (CLL) is the most common leukemia of adults in the western world and constitutes about 33% of all leukemia's. The incidence of CLL increases with age and are more common in older population. Chronic myeloid leukemia (CML) on the contrary occurs in both young adults and elderly and is a chronic myeloproliferative disease that originates from abnormal pluripotent stem cells and results in involvement of multiple hematopoietic lineages, but predominantly myeloid and less commonly lymphoid. Association between CLL and myeloid malignancies (CML, acute myeloid leukemia and MDS, myelodysplastic syndrome) is rare. In literature documenting CLL and CML in same patients, occur either simultaneously or CML is preceded by CLL.

Fibroblast growth factor-2 (FGF2) and syndecan-1 (SDC1) are potential biomarkers for putative circulating CD15+/CD30+ cells in poor outcome Hodgkin lymphoma patients.

BACKGROUND: High risk, unfavorable classical Hodgkin lymphoma (cHL) includes those patients with primary refractory or early relapse, and progressive disease. To improve the availability of biomarkers for this group of patients, we investigated both tumor biopsies and peripheral blood leukocytes (PBL) of untreated (chemo-naïve, CN) Nodular Sclerosis Classic Hodgkin Lymphoma (NS-cHL) patients for consistent biomarkers that can predict the outcome prior to frontline treatment. METHODS AND MATERIALS: Bioinformatics data mining was used to generate 151 candidate biomarkers, which were screened against a library of 10 HL cell lines. Expression of FGF2 and SDC1 by CD30+ cells from HL patient samples representing good and poor outcomes were analyzed by qRT-PCR, immunohistochemical (IHC), and immunofluorescence analyses. RESULTS: To identify predictive HL-specific biomarkers, potential marker genes selected using bioinformatics approaches were screened against HL cell lines and HL patient samples. Fibroblast Growth Factor-2 (FGF2) and Syndecan-1 (SDC1) were overexpressed in all HL cell lines, and the overexpression was HL-specific when compared to 116 non-Hodgkin lymphoma tissues. In the analysis of stratified NS-cHL patient samples, expression of FGF2 and SDC1 were 245 fold and 91 fold higher, respectively, in the poor outcome (PO) group than in the good outcome (GO) group. The PO group exhibited higher expression of the HL marker CD30, the macrophage marker CD68, and metastatic markers TGFß1 and MMP9 compared to the GO group. This expression signature was confirmed by qualitative immunohistochemical and immunofluorescent data. A Kaplan-Meier analysis indicated that samples in which the CD30+ cells carried an FGF2+/SDC1+ immunophenotype showed shortened survival. Analysis of chemo-naive HL blood samples suggested that in the PO group a subset of CD30+ HL cells had entered the circulation. These cells significantly overexpressed FGF2 and SDC1 compared to the GO group. The PO group showed significant down-regulation of markers for monocytes, T-cells, and B-cells. These expression signatures were eliminated in heavily pretreated patients. CONCLUSION: The results suggest that small subsets of circulating CD30+/CD15+ cells expressing FGF2 and SDC1 represent biomarkers that identify NS-cHL patients who will experience a poor outcome (primary refractory and early relapsing).

Rituximab, cyclophosphamide-fractionated, vincristine, doxorubicin and dexamethasone alternating with rituximab, methotrexate and cytarabine overcomes risk features associated with inferior outcomes in treatment of newly diagnosed, high-risk diffuse large B-cell lymphoma.

Subtypes of diffuse large B-cell lymphoma (DLBCL) that have inferior outcomes after front-line therapy with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) have been identified. While it is agreed that R-CHOP is probably not adequate in these patients, there is no standard treatment approach for patients with DLBCL with high-risk features. We present results of a retrospective cohort study of high-risk DLBCL (defined as having at least one unfavorable risk factor: non-germinal center [GC] subtype by immunohistochemistry [IHC], Ki-67 ≥ 80%, high International Prognostic Index [IPI], c-MYC rearrangement) treated with R-HCVAD/R-MTX-AraC (rituximab, cyclophosphamide-fractionated, vincristine, doxorubicin and dexamethasone alternating with rituximab, methotrexate and cytarabine; R-HCVAD) as front-line therapy. With a median follow-up of 25.3 months, the 3-year PFS and OS estimates are 79% (95% confidence interval [CI], 65-88%) and 76% (95% CI, 61-86%), respectively, which are higher than those for historical comparisons with R-CHOP data for high-risk patients. These data are in accord with other recent reports of dose-intense front-line therapy of high-risk DLBCL. This analysis represents the largest reported cohort of patients with DLBCL treated with R-HCVAD. These data suggest that R-HCVAD can overcome traditional poor risk features such as high IPI, high Ki-67 and non-GC IHC pattern. Future work will focus on identifying molecular markers for failure in patients with DLBCL treated with dose-intensive regimens.

γ-Synuclein is a promising new marker for staining reactive follicular dendritic cells, follicular dendritic cell sarcoma, Kaposi sarcoma, and benign and malignant vascular tumors.

Synucleins are small soluble proteins found in normal brain that facilitate rapid release of neurotransmitters. α-synuclein is a major component of the Lewy body of neurodegenerative diseases and γ-synuclein is a marker of aggressive carcinomas. As the role of γ-synuclein has not yet been investigated in the lymphoid system, we immunohistochemically stained normal lymphoid organs, lymph nodes with reactive lymphoid hyperplasia, and malignant lymphomas. The anti-γ-synuclein antibody strongly stained the follicular dendritic cell (FDC) meshworks and vascular and lymphatic endothelial cells in reactive lymphoid tissues, in B-cell lymphomas with a nodular pattern, and in angioimmunoblastic T-cell lymphomas. There were no γ-synuclein-positive FDC meshworks in B-cell or T-cell lymphomas with a diffuse pattern. This is in contrast to CD21, which only stained the arms of the FDCs; γ-synuclein highlighted both the long slender cellular processes and the cell body, thereby clearly demonstrating the number of individual FDCs. In addition, γ-synuclein was strongly expressed by the neoplastic counterpart of reactive FDCs (FDC sarcoma) and by the neoplastic counterparts of normal lymphatic and vascular endothelial cells (Kaposi sarcoma, hemangioma, and angiosarcoma). Only a few spindle cell neoplasms (SSNs) derived from smooth muscle, peripheral nerve, or gastrointestinal stroma expressed γ-synuclein; however, γ-synuclein was not expressed by 11 other types of SSNs tested. These results suggest that γ-synuclein is a promising new adjunct marker for identifying reactive FDCs and for diagnosing FDC sarcoma and benign and malignant vascular tumors.

Spectrin isoforms: differential expression in normal hematopoiesis and alterations in neoplastic bone marrow disorders.

Spectrins are large, rod-like, multifunctional molecules that participate in maintaining cell structure, signal transmission, and DNA repair. Because little is known about the role of spectrins in normal hematopoiesis and leukemogenesis, we immunohistochemically stained bone marrow biopsy specimens from 81 patients for αI, αII, ßI, and ßII spectrin isoforms in normal reactive marrow (NRM), myelodysplastic syndrome, myeloproliferative neoplasm, acute myeloid leukemia (AML) with well-characterized cytogenetic abnormalities, acute erythroid leukemia (EryL), and acute megakaryoblastic leukemia (MegL). In NRM, spectrin isoforms were differentially expressed according to cell lineage: αI and ßI in erythroid precursors; αII and ßII in granulocytes; and ßI and ßII in megakaryocytes. In contrast, 18 (44%) of 41 AMLs lacked αII spectrin and/or aberrantly expressed ßI spectrin (P = .0398; Fisher exact test) and 5 (100%) of 5 EryLs expressed ßII spectrin but lacked ßI spectrin. The frequent loss and/or gain of spectrin isoforms in AMLs suggests a possible role for spectrin in leukemogenesis.

Alpha- and beta-synucleins are new diagnostic tools for acute erythroid leukemia and acute megakaryoblastic leukemia.

α-Synuclein is a key component of the Lewy body, a large globular protein complex that forms in the nervous system of patients with Parkinson disease and other dementias [1-3]. Since α-synuclein also occurs in megakaryocytic and erythroid lineages [4-7], we wondered what role synucleins had in the hematopoietic system. Therefore, we studied the expression of α-, ß-, and γ-synucleins in a comprehensive panel of patient bone marrows and leukemic cell lines. We observed under expression of α-synuclein in the megakaryocytes of myeloproliferative neoplasm (MPN), but not normal reactive marrow (NRM) or myelodysplastic syndrome (MDS). Conversely, we observed over expression of ß-synuclein in the blasts of megakaryoblastic leukemias (MegL), but not acute myeloid leukemia (AML) or erythroleukemia (EryL), suggesting that α- and ß-synucleins could be useful adjunct markers for the early detection of MDS and the differential diagnosis of EryL and MegL from other AMLs.

Kaposi sarcoma-associated herpesvirus (human herpesvirus type 8)-associated extracavitary lymphoma: Report of a case in an HIV-positive patient with simultaneous kaposi sarcoma and a review of the literature.

BACKGROUND: Kaposi sarcoma-associated herpesvirus (KSHV), or human herpesvirus type 8 (HHV8), is consistently identified in 2 human immunodeficiency virus (HIV)-associated lymphoproliferative disorders: primary effusion lymphoma (PEL) and multicentric Castleman disease. Rarely, KSHV/HHV8-positive extracavitary solid tissue lymphomas occur, often at extranodal sites, which are not associated with an effusion. These solid variants of PEL are similar morphologically, immunophenotypically, clinically and genetically to classic PEL. CASE REPORT: Here we report a case of a 46-year-old HIV-positive patient with lymphadenopathy and Kaposi sarcoma of the skin. The lymph node biopsy shows a KSHV/HHV8-positive high-grade B-cell lymphoma with co-infection with Epstein-Barr virus, which supports the diagnosis of a solid variant of PEL. The same lymph node is also multifocally involved in Kaposi sarcoma. CONCLUSION: Analysis of viral infection is of primary importance to define this solid variant of PEL. The exact oncogenic mechanisms of HHV8 are not clearly defined. It is believed that it is related to a few latent viral gene products including ORF73, ORF72, and ORF71 which increase proliferation and impair apoptosis through variant regulatory processes. To the best of our knowledge, this is the first reported case of solid tissue PEL along with Kaposi sarcoma involving the same anatomic site.

A unique case of merkel cell carcinoma and chronic lymphocytic leukaemia presenting in a single cutaneous lesion (collision tumour).

A 58-year-old man with 10 year history of chronic lymphocytic leukaemia (CLL) presented with a bulging mass (3.2×1.6×1.5 cm) in the right anterior abdominal wall. On microscopic examination the mass was found to be an epithelial neoplasm in the background of lymphoid proliferation. The epithelial cells were of moderate size, with scant cytoplasm and round nuclei, forming glandular, alveolar or sheet-like structures. These cells were immunoreactive for cytokeratin 20, chromogranin and synaptophysin. The above findings supported a diagnosis of Merkel cell carcinoma (MCC). The background small lymphocytes expressed phenotypic markers of B cells (CD20) and CD5, consistent with his known diagnosis of CLL. The incidence of a patient with a known history of CLL who develops a secondary MCC is rare. This is believed to be the second case report of a single lesion containing CLL and MCC.

AIDS and non-AIDS diffuse large B-cell lymphomas express different antigen profiles.

Based on gene expression profiling, diffuse large B-cell lymphomas arising in immunocompetent patients can be divided into germinal center and activated B-cell types. Since little is known about acquired immunodeficiency syndrome associated diffuse large B-cell lymphomas, we tested whether the protein expression of germinal center and activated B-cell markers differed between acquired immunodeficiency syndrome (AIDS) vs non-AIDS diffuse large B-cell lymphomas. We immunohistochemically stained tissue microarrays of 39 de novo diffuse large B-cell lymphomas: 12 AIDS associated and 27 non-AIDS, with germinal center (BCL6, CD10, CyclinH) and activated B-cell markers (MUM1, CD138, PAK1, CD44, BCL2). We scored each case for percent positive cells (0-19%=0; 20-49%=1; 50-100%=2). The activated B-cell and germinal center summation scores of each case were used as (x, y) coordinate data points to construct two-dimensional contour-frequency plots. The contour plot of non-AIDS diffuse large B-cell lymphomas showed two distinct clusters: a cluster with a high germinal center phenotype (cluster 1) and a cluster with a high activated B-cell phenotype (cluster 3). In contrast, the AIDS-related diffuse large B-cell lymphomas formed a single aggregate (cluster 2) (P=0.02, Fisher exact test). When the contour plots of the AIDS-related and the non-AIDS cases were superimposed, cluster 2 of the AIDS cases expressed an intermediate germinal center/activated B-cell phenotype compared to clusters 1 and 3 of the non-AIDS diffuse large B-cell lymphomas. Our results confirm that non-AIDS diffuse large B-cell lymphomas segregate into two groups with either germinal center or activated B-cell phenotype. We report the new finding that the AIDS status of the patient predicts the immunophenotype of the diffuse large B-cell lymphomas.

Germinal center and activated b-cell profiles separate Burkitt lymphoma and diffuse large B-cell lymphoma in AIDS and non-AIDS cases.

Morphologic features of Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) overlap. No single phenotypic marker or molecular abnormality is pathognomonic. We tested a panel of 8 germinal center (GC) and activated B-cell (ABC) markers for their ability to separate BL and DLBCL. We diagnosed 16 BL and 39 DLBCL cases from 21 patients with AIDS and 34 without AIDS based on traditional morphologic criteria, Ki-67 proliferative index, and c-myc rearrangement (fluorescence in situ hybridization). After immunohistochemically staining tissue microarrays of BL and DLBCL for markers of GC (bcl-6, CD10, cyclin H) and ABC (MUM1, CD138, PAK1, CD44, bcl-2), we scored each case for the percentage of positive cells. Hierarchical clustering yielded 2 major clusters significantly associated with morphologic diagnosis (P < .001). For comparison, we plotted the sum of the GC scores and ABC scores for each case as x and y data points. This revealed a high-GC/low-ABC group and a low-GC/high-ABC group that were associated significantly with morphologic diagnosis (P < .001). Protein expression of multiple GC and ABC markers can separate BL and DLBCL.