Case Report: First Occurrence of Plasmablastic Lymphoma in Activated Phosphoinositide 3-Kinase δ Syndrome.

Activated phosphoinositide 3-kinase δ syndrome (APDS) is an autosomal dominant primary immunodeficiency caused by acquired gene function mutation (GOF). APDS has a variety of clinical phenotypes, particularly recurrent respiratory infections and lymphoproliferation. Here we report a pediatric patient with APDS who presented with recurrent respiratory infections, lymphoproliferation, hepatosplenomegaly, bronchoscopy suggesting numerous nodular protrusions in the airways and a decrease in both T and B lymphocytes, and progression to plasmablastic lymphoma (PBL) after 1 year. Whole exome sequencing revealed a heterozygous mutation in the PIK3CD gene (c.3061 G>A p.E1021K). This is the first reported case of APDS combined with PBL and pediatricians should follow up patients with APDS regularly to be alert for secondary tumours.

Plasmablastic Lymphomas: Characterization of Tumor Microenvironment Using CD163 and PD-1 Immunohistochemistry.

This study aims to characterize the tumor microenvironment of plasmablastic lymphoma (PBL) in regard to the quantities of CD163(+) tumor associated macrophages (TAM) and PD1(+) tumor infiltrating lymphocytes (TIL). This article also reviews the existing knowledge of the role of PD-1/PD-L1 pathway in the tumor microenvironment of hematopoietic neoplasms, discusses potential mechanisms to explain our findings, and outlines areas for future studies. We performed CD163 and PD1 immunohistochemical studies in 11 cases classified as plasmablastic lymphoma, and recorded the percentages of positive TAMs and TILs. Based on previous studies, cut off values of ≥30% and >5% were used to classify the cases into high TAMs and TILs, respectively. We determined that the majority of cases (8 of 11, or 73%) had high percentage of TAMs, while only a minority had high percentage of TILs (3 of 11, or 27%). Our data shows a trend towards a negative correlation between TAMs and TILs (p=0.08), and a predominance of the pattern TAMhigh/TILlow (7 of 11, or 63%) compared to other patterns. The microenvironment of plasma-blastic lymphoma tends to show high percentage of TAMs (≥30%) combined with low percentage of TILs (≤5%). Additional studies are needed to determine the clinical significance of TILs and the influence of EBV and HIV infections on numbers of TILs in PBL. As high microenvironment TAMs have been associated with high microenvironment PD-L1 in other hematopoietic malignancies, our data supports the need for future studies on the expression of PD-L1 in PBL.

Plasmablastic lymphoma presenting as a brachial artery aneurysm associated with haemodialysis arteriovenous access ligation in a renal transplant patient.

INTRODUCTION: Plasmablastic lymphoma is a rare and aggressive neoplasm, generally associated with immunodeficiencies and related to latent Epstein-Barr virus infection. This case is the first reported case of plasmablastic lymphoma relapse in aneurysmatic brachial artery wall. CASE DESCRIPTION: We describe the case of male patient who underwent cadaveric donor kidney transplant when he was 61 years old and radio-cephalic distal arteriovenous fistula ligation 8 months later. After 8 years, he developed gingival plasmablastic lymphoma treated with cyclophosphamide, hydroxydaunorubicin, oncovin and prednisone regimen with subsequent remission. During follow-up, a mid-forearm vascular access was created because of the worsening of renal function. Twenty-two months later, the patient showed a symptomatic 20 mm brachial artery aneurysm with radiological signs of imminent rupture, for which he was surgically treated. The histological evaluation of the brachial artery specimen revealed a relapse of plasmablastic lymphoma in the arterial wall and in an adjacent lymph node. CONCLUSION: Brachial artery aneurysms are a rare complication in kidney transplant recipients after ligation of arteriovenous access for haemodialysis. Here, we report a case in which this condition is associated with an even rarer plasmablastic lymphoma. A common aetiology, due to immunosuppressive therapy, is postulated for the two coexisting diseases.

Class-Switch Recombination Occurs Infrequently in Germinal Centers.

Class-switch recombination (CSR) is a DNA recombination process that replaces the immunoglobulin (Ig) constant region for the isotype that can best protect against the pathogen. Dysregulation of CSR can cause self-reactive BCRs and B cell lymphomas; understanding the timing and location of CSR is therefore important. Although CSR commences upon T cell priming, it is generally considered a hallmark of germinal centers (GCs). Here, we have used multiple approaches to show that CSR is triggered prior to differentiation into GC B cells or plasmablasts and is greatly diminished in GCs. Despite finding a small percentage of GC B cells expressing germline transcripts, phylogenetic trees of GC BCRs from secondary lymphoid organs revealed that the vast majority of CSR events occurred prior to the onset of somatic hypermutation. As such, we have demonstrated the existence of IgM-dominated GCs, which are unlikely to occur under the assumption of ongoing switching.

Interleukin-6-dependent growth in a newly established plasmablastic lymphoma cell line and its therapeutic targets.

Plasmablastic lymphoma (PBL) is a rare, highly aggressive subtype of non-Hodgkin lymphoma with plasma-cell differentiation occurring typically in immune-suppressed patients such as those with AIDS. This study reports the establishment and characterization of a new cell line, PBL-1, derived from a patient with AIDS-associated PBL. Morphological assessment of PBL-1 indicated plasma-cell differentiation with a CD20(-) CD38(+) CD138(+) immunophenotype and IgH/c-myc translocation. The cell line harbours Epstein-Barr virus, but a 52.7-kbp length defect was identified in its genome, resulting in no expression of viral microRNAs encoded in the BamHI-A Rightward Transcript region. Importantly, supplementation of culture medium with >5 ng/mL of interleukin-6 (IL-6) was required for PBL-1 growth. Starvation of IL-6 or addition of tocilizumab, an inhibitory antibody for the IL-6 receptor, induced apoptosis of PBL-1. Transduction of IL-6 into PBL-1 by lentivirus vector induced autologous growth without IL-6 supplementation of culture medium. These data indicate the IL-6 dependency of PBL-1 for proliferation and survival. mTOR inhibitors induced cell death effectively, suggesting mTOR in the IL-6 signalling pathway is a potential therapeutic target for PBL. This established PBL cell line will be a useful tool to further understand the pathophysiology of PBL and aid the future development of PBL treatment.

Clinical characteristics and prognostic factors of plasmablastic lymphoma patients: analysis of 135 patients from the LYSA group.

Background: Plasmablastic lymphoma (PBL), initially described in 1997 in the oral cavity of HIV positive patients, is now recognized as a distinct aggressive and rare entity of diffuse large B-cells lymphoma by the World Health Organization (WHO) classification. Since the original description, others cases have been reported. However, these are largely derived from case reports or small series limiting any definitive conclusions on clinical characteristics and outcome. Patients and methods: The clinical, biological, pathological features and outcome of a cohort including 135 patients with PBL, from LYSA centers in France and Belgium, were reported and analyzed. Results: The median age was 58 years, with a male predominance. The cohort was divided into 56 HIV-positive patients, 17 post-transplant patients and 62 HIV-negative/non-transplanted patients. Within HIV-negative/non-transplanted, a relative immunosuppression was found in most cases (systemic inflammatory disease, history of cancer, increased age associated with weakened immune system). We have also described a new subtype, PBL arising in a chronic localized inflammatory site, without any sign of immunosuppression. At presentation, 19% of patients showed oral involvement. Immunophenotype showed CD138 positivity in 88% of cases and CD20 negativity in 90% of cases. Chemotherapy was administered to 80% of patients, with a complete response (CR) rate of 55%. The median overall survival (OS) was 32 months. In univariate analysis, HIV positive status showed better OS when compared with HIV negative status. In multivariate analysis, International Prognostic Index score, chemotherapy and CR were associated with survival benefit. Conclusion(s): This cohort, the largest reported to date, increases the spectrum of knowledge on PBL, rarely described. However, specific guidelines to clarify treatment are lacking, and may improve the poor prognosis of this rare disease.

Plasmablastic lymphoma: an atypical cutaneous presentation of a rare entity.

Plasmablastic lymphoma is a very rare B-cell lymphoma typically associated with immunosuppression: It occurs primarily in the oral cavity, although some cases were reported in other organs and tissues.To date, only 10 cases of primary cutaneous plasmablastic lymphoma have been described. Clinically, primary cutaneous plasmablastic lymphoma presents as non-specific cutaneous lesions (purple nodules, erythematous infiltrated plaques). In previously described cases, as in this case, histology and immunohistochemistry are required to make the diagnosis. Owing to the rarity of this entity, there is no established therapy, which makes its management an individualized, patient-based decision.

Primary Posttransplant Plasmablastic Lymphoma of the Tongue: Report of a Case With Immunohistochemical and Molecular Studies.

Plasmablastic lymphoma is a rare, highly aggressive lymphoma characterized by large lymphoid cells with immunoblastic or plasmablastic features, absent expression of CD45 and CD20, positivity for CD138, and monoclonal rearrangement of the immunoglobulin heavy chain gene. It was originally reported in oral cavity in the setting of underlying human immunodeficiency viral infection but may occur also in lymph nodes or extranodal sites after transplantation and, more rarely, immunocompetent patients. Herein, we report a case of PBL presenting as an ulcerated lesion of the tongue in an HIV-negative patient, 6 years after renal transplantation. To date, only rare cases of plasmablastic lymphoma presenting after solid organ transplantation have been reported. Although a reduction of immunosuppression and an aggressive chemotherapy were performed, the patient died after a few months because of septic and cardiovascular complications.

Case of plasmablastic lymphoma of the sigmoid colon and literature review.

Plasmablastic lymphoma (PBL) is a rare form of non-Hodgkin's lymphoma that is associated with human immunodeficiency virus (HIV) infection. Although PBL is most commonly observed in the oral cavity of HIV-positive patients, it can also be observed at extra-oral sites in HIV-negative patients. This report represents an unusual case of HIV-negative PBL that occurred in the sigmoid colon. This patient had a history of systemic lupus erythematosus and an underlying immunosuppressive state from long term steroid therapy. The lymphoma cells were positive for CD138, kappa light chain restriction and Epstein-Barr virus and negative for CD20/L26, CD3, CD79a, UCHL1 (CD45RO) and cytokeratin (AE1/AE3). The patient died approximately 2 mo after the operation. In the present paper, we review cases of PBL of the colon in HIV-negative patients.

Clinicopathologic features of plasmablastic lymphoma: Single-center series of 8 cases from Saudi Arabia.

BACKGROUND: Plasmablastic lymphoma (PBL) is a rare subtype of non-Hodgkin's lymphoma. Characterized by its aggressive nature and plasmacytic differentiation, PBL remains a therapeutic and diagnostic challenge; it generally has a poor prognosis with very few long-term survivors and most patients dying within 2 years from initial presentation. PBL has been reported in several other countries; however, there have been no reported cases from Saudi Arabia. Here, we report 8 cases of PBL depicting the clinical presentation, immunocompetency, immunphenotypic characterization, diagnostic challenges and treatment outcome. METHODS: The medical records were reviewed for clinical presentation, staging, laboratory data, radiological studies, treatments, and outcomes. A broad immunohistochemical panel consisting of CD45, CD3, CD20, CD79a, Pax5, CD38, CD138, MUM1, EMA, Kappa, Lambda, CD 56, CD30, Bcl-2, Bcl-6, Alk-1, Ki-67, EBV-LMP-1, and HHV8 was performed. RESULTS: The tumors predominantly exhibited immunoblastic/plasmablastic or plasmacytic morphologic features and had a plasma cell-like immunophenotype. All cases were immunoreactive for CD38, CD138 and MUM1 confirming plasma cell differentiation of the tumor cells. CD20 was negative for all cases; whereas CD79a and Pax5 were weakly positive in 2cases. All 8 cases were EBV-LMP-1/EBER-1 negative, and 1 case was HHV8 positive. Similar to previously published studies, PBL in Saudi Arabia is characterized by male predominance (6/8), median age 51.5 years (mean age 46 years), associated with early dissemination, poor response to therapy, and limited survival (average survival time, 6.4 months, median overall survival 5.5 months). However, it does have some unique features. It occurs more commonly in immunocompetent persons (6/8, 75%), is not associated with EBV infection (0/8), and nodal involvement (either primary or secondary) is common among patients (6/8). In addition, extra-oral sites are more common than oral/nasal cavities (7/8) and the c-myc gene is not common (1/8, 12.5%). CONCLUSION: It appears that PBL is heterogeneous in terms of clinical presentation and morphology. PBL is a therapeutic challenge with a clinical course that is characterized by its high rate of relapse and death. To date, treatment responses are usually partial and temporary. Therapies that are more intensive than CHOP do not seem to prolong survival. Further research is needed to understand the biology and molecular pathogenesis of PBL in order to improve therapies. VIRTUAL SLIDES: The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1465801416161912.