Plasmablastic lymphoma in HIV-positive patients: an aggressive Epstein-Barr virus-associated extramedullary plasmacytic neoplasm

Oral Plasmablastic Lymphoma: A Rare Manifestation of HIV-Related Neoplasm-A Brief Clinical Study

Plasmablastic lymphoma (PBL) is an uncommon and aggressive large B-cell lymphoma commonly diagnosed in human immunodeficiency virus-positive patients. Though the oral cavity is a common site for PBL, this condition is not commonly reported in the literature as an oral manifestation. Most oral PBLs presented as an asymptomatic swelling, frequently associated with ulcerations and bleeding. No standard treatment is yet advocated for oral PBL. Five-year survival rate was recorded not more than 33.5%. This presentation emphasizes on oral manifestation of plasmablastic lymphoma (PBL) as a rare entity, which was provisionally diagnosed for carcinoma (CA) oral cavity. A simple presentation of ulcerated growth in the upper jaw was excised for histopathologic evaluation. Subsequently, it turned out to be a rare oral manifestation of HIV-related lymphoma. It is imperative to understand simple oral presentation as a manifestation of an underlying systemic condition. With this interest, this case presentation is published with a literature review.

Update: The molecular spectrum of virus-associated high-grade B-cell non-Hodgkin lymphomas

The vast spectrum of aggressive B-cell non-Hodgkin neoplasms (B-NHL) encompasses several infrequent entities occurring in association with viral infections, posing diagnostic challenges for practitioners. In the emerging era of precision oncology, the molecular characterization of malignancies has acquired paramount significance. The pathophysiological comprehension of specific entities and the identification of targeted therapeutic options have seen rapid development. However, owing to their rarity, not all entities have undergone exhaustive molecular characterization. Considerable heterogeneity exists in the extant body of work, both in terms of employed methodologies and the scale of cases studied. Presently, therapeutic strategies are predominantly derived from observations in diffuse large B-cell lymphoma (DLBCL), the most prevalent subset of aggressive B-NHL. Ongoing investigations into the molecular profiles of these uncommon virus-associated entities are progressively facilitating a clearer distinction from DLBCL, ultimately paving the way towards individualized therapeutic approaches. This review consolidates the current molecular insights into aggressive and virus-associated B-NHL, taking into consideration the recently updated 5th edition of the WHO classification of hematolymphoid tumors (WHO-5HAEM) and the International Consensus Classification (ICC). Additionally, potential therapeutically targetable susceptibilities are highlighted, offering a comprehensive overview of the present scientific landscape in the field.

Unusual bilateral kidney and duodenal plasmablastic lymphoma presentation in an elderly patient: A case report

The present report described the case of a 71-year-old man who was admitted to the emergency department with a 7-day history of progressive left flank pain and tarry stool. Bedside point-of-care ultrasound of the left kidney showed lobulated ill-defined hypoechoic foci in the perirenal spaces with mild hydronephrosis. Subsequent contrast-enhanced abdominal computed tomography revealed lobulated low-density lesions in the bilateral perirenal space and paraaortic space. The patient was subsequently admitted to the internal medicine department of the hospital. Renal and duodenal biopsies were arranged, and pathology reports were consistent with the findings of plasmablastic lymphoma (PBL). This unusual presentation of flank pain and tarry stool caused by recurrent PBL highlighted that genitourinary or gastrointestinal manifestations could occur in cases of PBL recurrence. The patient received intensive chemotherapy regimens comprising a combination of etoposide, prednisone, vincristine, cyclophosphamide and doxorubicin hydrochloride for aggressive non-Hodgkin's lymphoma to achieve a good response.

Plasmablastic Lymphoma of the Small Intestine in an HIV- and EBV-negative Patient

Plasmablastic lymphoma (PBL) is a rare aggressive B-cell lymphoproliferative disorder that is strongly associated with immunodeficiency, most often with human immunodeficiency virus (HIV) and Epstein-Barr virus (EBV) infection, and that mainly occurs in the oral cavity. Although some clinical features can lead to a diagnosis, PBL in an extraoral site is difficult to suspect clinically in a patient who is HIV negative. The small intestine as a site of PBL has also been described very rarely. We herein present a rare case of PBL of the small intestine in an 85-year-old HIV- and EBV-negative male.

MAP-kinase and JAK-STAT pathways dysregulation in plasmablastic lymphoma

Plasmablastic lymphoma (PBL) is an aggressive B-cell lymphoma with an immunoblastic/large cell morphology and plasmacytic differentiation. The differential diagnosis with Burkitt lymphoma (BL), plasma cell myeloma (PCM) and some variants of diffuse large B-cell lymphoma (DLBCL) may be challenging due to the overlapping morphological, genetic and immunophenotypic features. Furthermore, the genomic landscape in PBL is not well known. To characterize the genetic and molecular heterogeneity of these tumors, we investigated thirty-four PBL using an integrated approach, including fluorescence in situ hybridization, targeted sequencing of 94 B-cell lymphoma related genes, and copy-number arrays. PBL were characterized by high genetic complexity including MYC translocations (87%), gains of 1q21.1-q44, trisomy 7, 8q23.2-q24.21, 11p13-p11.2, 11q14.2-q25, 12p and 19p13.3-p13.13, losses of 1p33, 1p31.1-p22.3, 13q and 17p13.3-p11.2, and recurrent mutations of STAT3 (37%), NRAS and TP53 (33%), MYC and EP300 (19%) and CARD11, SOCS1 and TET2 (11%). Pathway enrichment analysis suggested a cooperative action between MYC alterations and MAPK (49%) and JAK-STAT (40%) signaling pathways. Of note, EBVnegative PBL cases had higher mutational and copy-number load and more frequent TP53, CARD11 and MYC mutations, whereas EBV-positive PBL tended to have more mutations affecting the JAK-STAT pathway. In conclusion, these findings further unravel the distinctive molecular heterogeneity of PBL identifying novel molecular targets and the different genetic profile of these tumors related to EBV infection.

MYC status in HIV-associated plasmablastic lymphoma: dual-colour CISH, FISH and immunohistochemistry

AIMS

We utilised chromogenic and fluorescence in-situ hybridisation (CISH and FISH) to evaluate MYC gene copy numbers and rearrangements within HIV-associated plasmablastic lymphomas (PBLs). Thereafter, clinicopathological features were explored retrospectively.

METHODS AND RESULTS

Sixty-seven (n = 67) patients were included and the HIV seropositive status was confirmed in 98% (63 of 64) with a median viral load of 55 587 (IQR 273 582) copies/ml and median CD4 count of 170 (IQR 249) cells/µl. The mean age was 41 ± 10.1 years and females comprised 54%. PBL was documented predominantly at extra-oronasal topographic regions. Starry-sky (SS) appearance was evident in 33% in association with monomorphic morphology (P-value 0.02). c-MYC protein was expressed in 81% and latent EBV infection was detected in 90%. EBER ISH-positive status and MYC rearrangement occurred in 67% of HIV PBL. MYC aberrations included MYC rearrangement (70%), low-level increase in MYC gene copy numbers (43%), concurrent MYC rearrangement and increased MYC gene copy numbers (49%) as well as low-level chromosome 8 polysomy (6%). MYC aberrations in HIV PBLs were significantly associated with SS appearance (P -0.01), monomorphic morphology (P - 0.03), c-MYC protein expression ≥40% (P - 0.03) and mortality (P - 0.03). There was advanced stage (Ann Arbor III/IV) at presentation (77%) and the median overall survival for HIV PBL was 75 days (95% CI 14-136).

CONCLUSION

Majority of the HIV-associated PBL tumours harbour MYC aberrations. Due to the persistently inferior survival outcome of HIV-associated PBL in the era of antiviral treatment, targeted and/or intensified therapy of oncogenic MYC may need to be explored in future.

Plasmablastic Lymphoma Associated with Adjacent Mature Plasma Cell Population Exhibiting Opposite Light Chain Restriction

Plasmablastic lymphoma (PBL) is an aggressive high-grade B cell lymphoma, considered a variant of diffuse large B cell lymphoma with approximately 75% mortality within 6-7 months. We describe an unusual case of PBL arising as a maxillary mass in an HIV-negative, nontransplanted 78-year-old female. Histologic examination revealed a diffuse infiltrate of anaplastic appearing cells exhibiting plasmablastic morphology with an adjacent contiguous infiltrate of mature appearing plasma cells. The PBL and mature plasma cell components both demonstrated an immunophenotype of CD20(-), CD38(+), and CD138(+). The two populations differed by the PBL featuring a high proliferation rate by Ki-67 (~95%) with coexpression of both c-MYC and EBV, while the mature plasma cell component featured a low proliferation rate by Ki-67 (~5%) without coexpression of c-MYC or EBV. Kappa/lambda staining demonstrated lambda light chain restriction involving the PBL, while the mature plasma cell infiltrate revealed kappa light chain restriction. Our findings describe the rare association of PBL with a synchronous distinct population of mature plasma cells exhibiting opposite light chain restriction.

Plasmablastic lymphoma in immunocompetent and in immunocompromised patients: Experience at a regional cancer centre in India

Introduction:

Plasmablastic lymphoma (PBL) is a rare lymphoma associated with immunosuppression. It is strongly associated with immunosuppression (human immunodeficiency virus [HIV]) and often occurs within the oral cavity. PBL is also seen in patients receiving immunosuppressive therapy; however, despite its predisposition for the immunocompromised patients, PBL has been diagnosed in immunocompetent patients.

Aim:

This study aims to prognostic factors and outcome of PBL in immunocompromised and in immunocompetent patients.

Materials and Methods:

We conducted a retrospective study at our institute from the year 2008 to 2015.

Results:

A total of 13 patients (8 males and 5 females) with PBL were identified. Eight patients (61.5%) had extraoral PBL (median age 30.2 years) and 5 patients (38.5%) had oral PBL (median age 44 years). Most common extraoral site was gastrointestinal tract. Eight (61.5%) out of 13 patients were HIV positive. More than 50% of patients had Ann Arbor Stage III or IV. All the cases were CD20 negative and CD138 positive. Seven out of 13 patients had Ki-67 more than 80%. Nine patients received cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy. Three patients were on best supportive care due to poor performance status (PS). One patient received intensive chemotherapy with CODOX-M/IVAC. The median overall survival was 9 months in HIV-positive patients and 6 months in HIV-negative patients. The prognosis was worse in patients with Ki-67 of >80%.

Statistical Analysis:

Survival curves were generated using the Kaplan–Meier method and analyzed using log-rank test and Fisher's t-test.

Conclusion:

The present study confirms that PBL in both HIV-positive and in HIV-negative patients has an overall unfavorable outcome. The most important prognostic factors are stage, ki-67, and the Eastern Cooperative Oncology Group PS of the patient at the time of presentation.

A challenging diagnosis of a nonsecretor plasma cell dyscrasia with pleomorphic plasmablastic morphology

This report highlights the importance of integrating clinical, radiological, genetic, and pathological laboratory findings to make a correct diagnosis especially with challenging and rare entities.

Survival analysis in treated plasmablastic lymphoma patients: a population-based study

Herein we analyzed survival outcomes in chemotherapy-treated patients with plasmablastic lymphoma (PBL) diagnosed between 2010 to 2016 (n = 248). Data was acquired from the Surveillance, Epidemiology, and End Results (SEER) 18 registries database (April 2019 release based on November 2018 submission). The majority of patients were male (81.9%) and younger than 60 years (71.0%). Oral and gastrointestinal (GI) sites were the most frequent primary extranodal locations (23% and 19.4%, respectively). Oral primary location was inversely associated with presence of B symptoms and advanced Ann-Arbor stage. The 3-year and 5-year overall survival (OS) rates of treated PBL patients were 54% (95% CI: 46.5%-60.8%) and 52.8% (95% CI: 45.2%-59.8%). Three-year conditional survival for 2-year and 3-year survivors were 90.3% and 97.8%, overlapping the survival of a general population matched by age, sex and calendar year. In a multivariable analysis, oral primary location was associated with not only better OS (HR 0.43; 95% CI: 0.21-0.88, P = .021) but also better lymphoma-specific survival (LSS) (SHR 0.36; 95% CI: 0.15-0.86, P = .022); age ≥60 years was associated with shorter LSS (SHR 1.73; 95% CI: 1.02-2.96, P = .043). Seven registries granted access to HIV status (n = 93) where HIV infection was detected in 52.7% of cases. The HIV status did not affect survival outcomes in unadjusted and adjusted analyses. We identified clinical characteristics associated with survival and showed that treated PBL patients may achieve long-term survival.

Gastrointestinal Tract Plasmablastic Lymphoma in HIV-Infected Adults: A Histopathological Review

BACKGROUND.

Plasmablastic lymphoma (PBL) is an aggressive B-cell lymphoma that is characterized by the expression of plasma cell antigens and loss of pan B-cell antigens. The neoplasm is extensively reported in the oral cavity and anorectal region but rarely in the gastrointestinal tract, where only isolated case reports and small case series have been reported. In the current study, morphologic, immunohistochemical, and molecular features of 17 cases of gastrointestinal tract PBL were reviewed.

METHODS.

Ten-year retrospective study that reappraised the histomorphological and immunophenotypical profiles of HIV-associated PBLs in the gastrointestinal tract.

RESULTS.

The mean age of the study patients was 41 years with a 3:1 ratio of males to females. The most common site of tumor origin was the small intestine (42%), followed by the stomach (29%) and the colon (29%). Majority of the cases showed a predominant diffuse (82%) growth pattern. Immunoblasts and plasmablasts were observed in all cases. Plasmacytic differentiation was seen in 5 (29%) cases. Additional observations not previously described or emphasized in literature includes pseudo-alveolar growth pattern, centroblast-predominance, multinucleated giant cells, and clear cell change. Immunohistochemistry revealed absence of pan B-cell antigens and expression of plasma cell antigens in all cases. Epstein-Barr virus-encoded RNA was expressed in 53% of the cases.

CONCLUSIONS.

This study highlights the spectrum of histopathological features seen in gastrointestinal tract PBLs. Awareness of this entity and its histopathological features in the gastrointestinal tract is essential for making a timely and accurate diagnosis and improving patient outcomes.

Clinical, pathological and molecular features of plasmablastic lymphoma arising in the gastrointestinal tract: A review and reappraisal

Plasmablastic lymphoma (PBL) is a CD20-negative large B-cell lymphoma with a plasmacytic phenotype and a dismal prognosis, which has been defined as a distinct entity only in the 2008 WHO Classification of Haematopoietic and Lymphoid Tissue and confirmed in the 2017 Edition. Current knowledge of the biological, clinical and prognostic features of PBL is mostly limited, resulting in diagnostic issues, as well as in lack of standard of care and effective therapeutic options. PBL commonly affects the oral cavity of HIV-positive individuals, however the gastrointestinal (GI) tract is the most common extraoral site, and in this location most patients are HIV-negative. In this review, we focus on the clinical, morphological and prognostic features of PBL arising in the GI tract, in order to improve knowledge on this rare, but aggressive disease.

Lymphoid Neoplasms With Plasmablastic Differentiation: A Comprehensive Review and Diagnostic Approaches

Plasmablastic neoplasms encompass several entities including plasmablastic lymphoma, plasmablastic plasmacytoma/multiple myeloma, primary effusion lymphoma and its extracavitary variant, anaplastic lymphoma kinase-positive large B-cell lymphoma, and Kaposi sarcoma-associated herpesvirus/human herpesvirus 8 (HHV8)-positive diffuse large B-cell lymphoma, not otherwise specified. Morphologically, the tumor cells are large with eccentrically located nuclei, prominent nucleoli, and basophilic/amphophilic cytoplasm. Immunophenotypically, the tumor cells express plasma cell-related antigens including CD38, CD138, interferon regulatory factor-4 (IRF4)/MUM1, PR domain zinc finger protein-1 (PRDM1), and/or X-box binding protein-1 (XBP1), with frequent loss of CD20. These tumors are diagnostically challenging for general pathologists due to their overlapping morphology and immunophenotype, and due to their rarity, and particularly so when clinical and radiologic information is insufficient. We also discuss HHV8-negative effusion-based lymphoma due to its overlapping features with primary effusion lymphoma. In this review, we focus on the useful diagnostic markers and pertinent molecular findings in these distinct entities and propose a practical diagnostic algorithm using anaplastic lymphoma kinase, HHV8, in situ hybridization for Epstein-Barr virus-encoded small RNA, immunoglobulin M, light chain stains, and clinicoradiologic criteria to avoid misdiagnosis. At the molecular level, MYC protein overexpression with or without MYC rearrangement and PRDM1-inactivating mutations or deletions are noted in a subset of such tumors, especially in plasmablastic lymphoma. Prognosis in these entities is dismal with conventional CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy. Therefore, novel target therapies, such as anti-CD30 agents, and/or immune blockade therapy, are potential treatment options in the future.

KSHV/HHV8-positive large B-cell lymphomas and associated diseases: a heterogeneous group of lymphoproliferative processes with significant clinicopathological overlap

In this review, we focus on the current understanding of the diagnosis of human herpesvirus 8 (HHV8)-associated lymphoproliferative disorders-a group of entities that range from hyperplastic proliferations to frank lymphomas. These diseases tend to occur in immunodeficient patients, but may occur in immunocompetent individuals as well. In recent years, we have learned of occasional cases with overlapping features among HHV8 entities, such as lesions intermediate between primary effusion lymphoma and HHV8-positive diffuse large B-cell lymphoma, not otherwise specified or cases sharing features of multicentric Castleman disease and germinotropic lymphoproliferative disorder. There is also a significant clinical overlap between these entities. It is important to have a better understanding of the biology of these lesions and to refine diagnostic criteria of these lesions, as the use of immunosuppressive agents to treat a variety of diseases, the expanded use of transplant as a therapeutic modality for a variety of cancers and organ failure patients, and the extended longevity of HIV-positive patients will likely result in an increased incidence of these lymphoproliferative processes in the future.

Extraoral plasmablastic lymphomas in a high human immunodeficiency virus endemic area

AIMS

Plasmablastic lymphoma (PBL) occurs mainly in immunocompromised individuals, usually secondary to human immunodeficiency virus (HIV) infection. It classically occurs intraorally, but has been described in extraoral locations. The aim of this study was to define the immunophenotype and Epstein-Barr virus (EBV) status in a large single-centre cohort of extraoral PBL (EPBL) in South Africa, a high-prevalence HIV setting.

METHODS AND RESULTS

This retrospective study of 45 EPBLs included patients' age, gender, race, HIV status, and site. Cases were reviewed histologically, and classified morphologically as pure plasmablastic or plasmablastic with plasmacytic differentiation, and assessed immunohistochemically with antibodies against CD45, CD20, CD79a, PAX5, CD138, MUM1/IRF4, BLIMP1, VS38c, Ki67, bcl-6, CD10, cyclin D1, and human herpesvirus-8, by the use of standard automated procedures. EBV was assessed by the use of chromogenic in-situ hybridisation. Tumours were assessed with a fluorescence in-situ hybridisation (FISH) MYC break-apart probe. Twenty-seven PBLs showed pure plasmablastic morphology, and 18 showed plasmacytic differentiation. The male/female ratio was 1.5:1. The anus was the favoured extraoral site (31.1%), followed by lymph nodes (15.6%). All 29 patients with known HIV status were HIV-positive. The immunohistochemical profile recapitulated that reported for oral PBLs and EPBLs in HIV-positive and HIV-negative patients. EBV was positive in 92.5% of PBLs. FISH analysis showed MYC rearrangement in 48% of cases.

CONCLUSION

This study showed a strong association of EPBLs with HIV and EBV infection, similarly to the previously described oral PBL. The strong EBV association together with other clinicopathological parameters and an immunohistochemical profile that includes CD45, CD20, MUM1/IRF4, CD138 and Ki67 may be used in distinguishing PBL from diffuse large B-cell lymphoma and plasma cell myeloma.

High incidence of MYC rearrangement in human immunodeficiency virus-positive plasmablastic lymphoma

AIMS

MYC rearrangements are the main cytogenetic alterations in plasmablastic lymphoma (PBL). We aimed to investigate the relationship between MYC rearrangement and the clinicopathological features of PBL.

METHODS AND RESULTS

MYC rearrangements assessed in 13 unpublished single-centre PBL cases, and an additional 85 cases from the literature, with reported MYC rearrangement information individualised by patient, were reviewed. In Asia, PBL was much less commonly diagnosed in human immunodeficiency virus (HIV)-positive patients (27% versus 84%, P = 0.000), with older age (median age at diagnosis: 52 years versus 44 years, P = 0.046) and a lower EBV infection rate (56.8% versus 81.8%, P = 0.049), than in non-Asian regions. Overall, MYC rearrangements were identified in 44 of 98 (44.9%) PBL cases, and IGH was the partner in almost all available cases (30/31, 96.8%), as confirmed with a MYC-IGH fusion probe. The MYC rearrangement rate in HIV-positive cases (33/55, 60.0%) was significantly higher than that in HIV-negative cases (11/38, 28.9%, P = 0.003). Patients with MYC rearrangement showed a trend towards an inferior median survival time (9.6 months versus 15.7 months, P = 0.122) and 2-year overall survival (17% versus 32%, P = 0.238).

CONCLUSIONS

MYC rearrangement was frequently identified in PBL patients, and IGH was the partner gene in an overwhelming majority of MYC rearrangements. In addition, the MYC rearrangement rate was significantly higher in HIV-positive PBL patients than that in HIV-negative patients. MYC rearrangement may play an important role in the pathogenesis of HIV-positive PBL, but further studies are required to understand the underlying mechanisms.

EBV-Associated Lymphoproliferative Disorders: Update in Classification

Although about 90% of the world's population is infected by EBV only a small subset of the related infections result in neoplastic transformation. EBV is a versatile oncogenic agent involved in a multitude of hematopoietic, epithelial, and mesenchymal neoplasms, but the precise role of EBV in the pathogenesis of many of the associated lymphoid/histiocytic proliferations remains hypothetical or not completely understood. Additional studies and use of evolving technologies such as high-throughput next-generation sequencing may help address this knowledge gap and may lead to enhanced diagnostic assessment and the development of potential therapeutic interventions.

Molecular Biology of EBV in Relationship to HIV/AIDS-Associated Oncogenesis

Herpesvirus-induced disease is one of the most lethal factors which leads to high mortality in HIV/AIDS patients. EBV, also known as human herpesvirus 4, can transform naive B cells into immortalized cells in vitro through the regulation of cell cycle, cell proliferation, and apoptosis. EBV infection is associated with several lymphoma and epithelial cancers in humans, which occurs at a much higher rate in immune deficient individuals than in healthy people, demonstrating that the immune system plays a vital role in inhibiting EBV activities. EBV latency infection proteins can mimic suppression cytokines or upregulate PD-1 on B cells to repress the cytotoxic T cells response. Many malignancies, including Hodgkin Lymphoma and non-Hodgkin's lymphomas occur at a much higher frequency in EBV positive individuals than in EBV negative people during the development of HIV infection. Importantly, understanding EBV pathogenesis at the molecular level will aid the development of novel therapies for EBV-induced diseases in HIV/AIDS patients.

[Clinical characteristics and survival analysis of eight cases HIV-negative plasmablastic lymphoma]

目的

提高对人免疫缺陷病毒（HIV）阴性浆母细胞淋巴瘤的认识。

方法

回顾性分析北京协和医院1997年1月至2015年5月确诊的8例HIV阴性浆母细胞淋巴瘤患者的临床资料，分析其临床特征及转归。

结果

8例HIV阴性浆母细胞淋巴瘤中男3例，女5例，中位年龄60（43~80）岁，其中4例存在导致免疫功能低下的疾病或状态。8例患者均有结外受累，2例Ann Arbor分期为Ⅰ~Ⅱ期，6例为Ⅳ期，其中5例有骨髓受累。所有患者均弥漫表达CD38和CD138，B细胞标志包括PAX-5及Bcl-6少见。5例患者进行EBV-DNA检测，均为阴性。接受化疗并规律随访的7例患者中位随访36（11~57）个月，中位无进展生存时间为15（6~52）个月，中位总生存时间为36（2~52）个月；其中4例采用了硼替佐米联合化疗，3例有效，但疗效难以维持，分别于治疗后2、9、21个月疾病进展。2例Ⅰ~Ⅱ期患者均治疗有效，未出现疾病进展，持续存活；5例Ⅳ期患者化疗后虽然有效，但疗效难以维持，中位总生存时间仅12（6~52）个月，中位无进展生存时间仅10（2~21）个月。

结论

该组HIV阴性浆母细胞淋巴瘤患者以中老年为主，临床呈现高侵袭性，均出现结外（尤其是骨髓）受累，其免疫表型与浆细胞瘤较为接近，分期较晚的患者预后不良。

Plasmablastic lymphoma: current perspectives

Plasmablastic lymphoma (PbL) is a rare and aggressive B-cell malignancy with large neoplastic cells, most of them resembling plasmablasts that have a CD20-negative phenotype. Although initially described as being associated with HIV, over the years it has also been identified in patients with solid organ transplant and immunocompetent patients. Little is known about molecular basis that drives PbL, and still its diagnosis remains challenging given its rarity. However, proper recognition of its clinical characteristics, localization, and morphological features can establish a correct diagnosis of PbL within the spectrum of CD20-negative large B-cell lymphomas (LBCLs). PbL is characterized by CD20 and PAX5 negativity together with the expression of CD38, CD138, MUM1/IRF4, Blimp1, and XBP1 plasmacytic differentiation markers. It is usually associated with Epstein–Barr virus infections, and MYC gene rearrangements. PbL should be carefully differentiated from other CD20-negative B-cell neoplasms, ie, primary effusion lymphoma, anaplastic lymphoma kinase-positive (ALK) large B-cell lymphoma, and LBCL in human herpesvirus 8-associated multicentric Castleman disease. Despite our improved understanding of this disease, its prognosis remains dismal with short overall survival. There is no standard of care for this entity. Several chemotherapy combinations have been used with hardly any differences on its outcome. Thus, new approaches with the addition of novel molecules are needed to overcome its poor prognosis. Our current understanding and knowledge of PbL relies primarily on case reports and small case series. In this review, we revise through an extensive literature search, the clinical and biological characteristics of this entity, and the potential therapeutic options.

Epstein-Barr virus (EBV)-associated lymphoid proliferations, a 2018 update

Epstein-Barr virus (EBV) has been linked to many human neoplasms including hematopoietic, epithelial, and mesenchymal tumors. Since our original review of EBV-associated lymphoproliferative disorders in 2007, many advances and developments have been reported. In this review, we will examine the recent advances in EBV-associated lymphoid/histiocytic proliferations, dividing them into reactive, B cell, T/NK cell, immunodeficiency-related, and histiocytic/dendritic cell proliferations.

Human herpesvirus-encoded kinase induces B cell lymphomas in vivo

Kaposi's sarcoma-associated herpesvirus (KSHV) is a gammaherpesvirus that is the etiological agent of the endothelial cell cancer Kaposi's sarcoma (KS) and 2 B cell lymphoproliferative disorders, primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD). KSHV ORF36, also known as viral protein kinase (vPK), is a viral serine/threonine kinase. We previously reported that KSHV vPK enhances cell proliferation and mimics cellular S6 kinase to phosphorylate ribosomal protein S6, a protein involved in protein synthesis. We created a mouse model to analyze the function of vPK in vivo. We believe this is the first mouse tumor model of a viral kinase encoded by a pathogenic human virus. We observed increased B cell activation in the vPK transgenic mice compared with normal mice. We also found that, over time, vPK transgenic mice developed a B cell hyperproliferative disorder and/or a high-grade B cell non-Hodgkin lymphoma at a greatly increased incidence compared with littermate controls. This mouse model shows that a viral protein kinase is capable of promoting B cell activation and proliferation as well as augmenting lymphomagenesis in vivo and may therefore contribute to the development of viral cancers.

Mechanisms of Immune Evasion and Immune Modulation by Lymphoma Cells

Purpose

Targeting cancer cells by modulating the immune system has become an important new therapeutic option in many different malignancies. Inhibition of CTLA4/B7 and PD1/PDL1 signaling is now also being investigated and already successfully applied to various hematologic malignancies.

Methods

A literature review of PubMed and results of our own studies were compiled in order to give a comprehensive overview on this topic.

Results

We elucidate the pathophysiological role of immunosuppressive networks in lymphomas, ranging from changes in the cellular microenvironment composition to distinct signaling pathways such as PD1/PDL1 or CTLA4/B7/CD28. The prototypical example of a lymphoma manipulating and thereby silencing the immune system is Hodgkin lymphoma. Also other lymphomas, e.g., primary mediastinal B-cell lymphoma and some Epstein–Barr virus (EBV)-driven malignancies, use analogous survival strategies, while diffuse large B-cell lymphoma of the activated B-cell type, follicular lymphoma and angioimmunoblastic T-cell lymphoma to name a few, exert further immune escape strategies each. These insights have already led to new treatment opportunities and results of the most important clinical trials based on this concept are briefly summarized. Immune checkpoint inhibition might also have severe side effects; the mechanisms of the rather un(der)recognized hematological side effects of this treatment approach are discussed.

Conclusion

Silencing the host’s immune system is an important feature of various lymphomas. Achieving a better understanding of distinct pathways of interactions between lymphomas and different immunological microenvironment compounds yields substantial potential for new treatment concepts.

A distinctive subgroup of oral EBV+ B-cell neoplasm with polymorphous features is potentially identical to EBV+ mucocutaneous ulcer

Epstein-Barr virus-positive mucocutaneous ulcer (EBVMCU) is a newly recognized provisional entity included in mature B-cell neoplasm in the latest 2016 World Health Organization Classification. It has a self-limited growth potential with a high predilection for oral cavities and occurs in age-related or iatrogenic immunodeficiency with indolent clinical courses. However, it shares histological features with EBV-positive diffuse large B-cell lymphoma (DLBCL), and this often leads to diagnostic challenges and controversies in patients with an oral EBV-positive B-cell neoplasm. The aim of this study was to better characterize and comprehend the pathophysiology of DLBCL and EBVMCU in the oral cavity. We conducted clinicopathologic and recurrent gene mutation analysis of 49 cases (14 EBV positive, 35 EBV negative), including cases diagnosed as DLBCL or B-cell lymphoproliferative disorders with high-grade morphology in the oral cavity. All EBV-positive cases matched the criteria of EBVMCU, with significantly earlier clinical stages than the EBV-negative group (P=.0006). Besides, histological analysis showed that all EBV-positive cases presented polymorphous features, whereas 91.4% (32/35) of the EBV-negative cases showed diffuse and monotonous proliferation (P<.0001). Furthermore, EBV-positive cases presented favorable clinical outcomes without disease-related death or recurrence. Gene mutation analysis (MYD88, CD79A, CD79B, CARD11, and EZH2) revealed that 33.3% (9/27) of EBV-negative cases harbored at least 1 gene mutation, whereas no gene mutation was observed in the EBV-positive group (0/11). These results suggest that oral EBV-positive B-cell lymphoid proliferation with polymorphous features often fulfill the criteria for EBVMCU, with clinicopathologically and genetically distinctive properties.

Intraocular Plasmablastic Lymphoma in a HIV Patient

Plasmablastic lymphoma (PBL) is a rare B-cell lymphoma occurring mainly in HIV patients. The tumor frequently involves extranodal sites such as the oral cavity, nasal cavity, gastrointestinal tract, skin, and lungs. The neoplastic cells are characterized by a plasmablastic appearance and typical immunophenotype that indicates plasma cell differentiation. Herein, we report a case of intraocular involvement by plasmablastic lymphoma in a HIV patient with a long history of cytomegalovirus retinitis and loss of vision. After an evisceration performed to control the blind, painful eye a diagnosis of PBL was made by examining the eye contents. Two months later, a biopsy of cervical lymph node revealed nodal lymphoma of the same type. To the best of our knowledge, this is the second case of intraocular PBL reported in English literature.

Plasma Cell Disorders in HIV Infected Patients: A Case Series

People Living with HIV (PLHIV) are at an increased risk of developing malignancies. Plasma cell disorders are also reported with increased incidence in PLHIV compared to the general population. Here, we describe three different plasma cell disorders among PLHIV and highlight their atypical presentations and outcomes in these subjects.

Diagnostic Algorithm of Common Mature B-Cell Lymphomas by Immunohistochemistry

CONTEXT

- Different types of mature B-cell lymphomas, including plasma cell neoplasms, exhibit distinct immunohistochemical profiles, which enable them to be correctly diagnosed. However, except for rare examples of lymphoma-specific immunohistochemistry, such as cyclin D1 in mantle cell lymphoma and annexin A1 in hairy cell leukemia, immunohistochemical profiles of mature B-cell lymphomas overlap and lack specificity.

OBJECTIVES

- To systemically review immunohistochemical features associated with commonly encountered mature B-cell lymphomas based on the presence or absence of CD5 and CD10; to review the immunophenotypic profile of plasma cells derived from plasma cell myelomas and B-cell lymphomas; and to review a group of rare, aggressive B-cell lymphomas with antigen expression features of plasma cells.

DATA SOURCES

- Published and PubMed-indexed English literature was reviewed.

CONCLUSIONS

- Although the presence or absence of CD5 and CD10 expression should be included in the initial immunohistochemistry screening panel for mature B-cell lymphomas, appropriate and judicial use of other B-cell antigens is necessary to ensure correct diagnoses. Furthermore, although the status of CD5 and CD10 expression is associated with certain prototypes of B-cell lymphomas, their expression is not specific. Plasma cells from plasma cell neoplasias and B-cell lymphomas exhibit overlapping but relatively distinct immunophenotypes; thus, a panel of immunohistochemical markers (CD19, CD45, CD56, and CD117) can be employed for their proper identification. Lastly, CD138 staining results are almost always positive in a group of aggressive B-cell lymphomas with plasmablastic features, including plasmablastic plasma cell myeloma, plasmablastic lymphoma, and ALK-1⁺ large B-cell lymphoma.

Mediastinal syndrome from plasmablastic lymphoma in human immunodeficiency virus and human herpes virus 8 negative patient with polycythemia vera: a case report

Background

Plasmoblastic lymphoma is a rare and aggressive subtype of diffuse large B cell lymphoma, which occurs usually in the jaw of immunocompromised subjects.

Case presentation

We describe the occurrence of plasmoblastic lymphoma in the mediastinum and chest wall skin of an human immunodeficiency virus-negative 63-year-old Caucasian man who had had polycytemia vera 7 years before. At admission, the patient showed a superior vena cava syndrome, with persistent dyspnoea, cough, and distension of the jugular veins. Imaging findings showed a 9.7 × 8 × 5.7 cm mediastinal mass. A chest wall neoformation biopsy and ultrasound-guided fine-needle aspiration biopsy of the mediastinal mass allowed diagnosis of plasmoblastic lymphoma and establishment of an immediate chemotherapeutic regimen, with rapid remission of compression symptoms.

Conclusions

Plasmoblastic lymphoma is a very uncommon, difficult to diagnose, and aggressive disease. The presented case represents the first rare mediastinal plasmoblastic lymphoma in a human immunodeficiency virus-/human herpesvirus-8-negative patient. Pathologists should be aware that this tumor does appear in sites other than the oral cavity. Fine-needle aspiration biopsy is a low-cost, repeatable, easy-to-perform technique, with a high diagnostic accuracy and with very low complication and mortality rates. Fine-needle aspiration biopsy could represent the right alternative to surgery in those patients affected by plasmoblastic lymphoma, being rapid and minimally invasive. It allowed establishment of prompt medical treatment with subsequent considerable reduction of the neoplastic tissue and resolution of the mediastinal syndrome.

HHV8/KSHV-Positive Lymphoproliferative Disorders and the Spectrum of Plasmablastic and Plasma Cell Neoplasms: 2015 SH/EAHP Workshop Report-Part 3

OBJECTIVES

The 2015 Workshop of the Society for Hematopathology/European Association for Haematopathology aimed to review immunodeficiency-related lymphoproliferative disorders with plasmablastic and plasma cell differentiation.

METHODS

The workshop panel reviewed human herpes virus 8 (HHV8)/Kaposi sarcoma herpesvirus (KSHV)-associated lesions and other lesions exhibiting plasma cell differentiation, including plasmablastic proliferations with features of myeloma/plasmacytoma, plasmablastic neoplasms presenting in extranodal sites and effusion-based lymphomas, and rendered a consensus diagnosis.

RESULTS

The spectrum of HHV8/KSHV-associated proliferations ranged from multicentric Castleman disease (MCD) to MCD with plasmablastic aggregates to HHV8+ diffuse large B-cell lymphoma and germinotrophic lymphoproliferative disorder. Comparisons across effusion-based lymphomas with and without HHV8/KSHV and plasmablastic lymphomas in immunodeficient and immunocompetent patients were discussed.

CONCLUSIONS

The presence or absence of HHV8/KSHV is a defining feature in disorders associated with Castleman disease, although their differential diagnosis and recognition of progression may be challenging. Plasmablastic proliferations overlap with myeloma/plasmacytoma as well as extranodal and effusion-based lymphomas. The involvement of Epstein-Barr virus is typically variable.

Plasmablastic lymphoma: oral presentation in patient suffering from osteradionecrosis of the jaw

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Unusual buccal plasmablastic lymphoma.

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In a immunocometent patient.

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Suffering from osteoradionecrosis after head and neck radiotherapy.

Introduction

We describe here an unusual presentation of a plasmablastic lymphoma in a patient suffering from an osteoradionecrosis of the jaw.

Presentation of case

We report the case of a 64-year-old patient who was followed up on oncology because of an oropharyngeal cancer treated by a combined procedure of both surgery and radio-chemotherapy procedure. This patient developed an osteoradionecrosis of the jaw. In the vicinity of this necrotic area appeared an ulceration which could evoke a new necrotic area. Given the persistence of this ulceration, a biopsy was performed which highlighted a plasmablastic lymphoma oral localization.

Discussion

The plasmablastic lymphoma, belonging to the diffuse large B-cell lymphoma family, is a very aggressive and unusual form of cancer with poor prognosis. If it is found mainly in patients with positive HIV, in whom it was first described, it is also found in immunosuppressed patients such as transplanted patients or patients suffering from leukaemia.

Conclusion

Plasmablastic lymphoma is a rare and an aggressive pathology in immunocompetent patients.

Long-Term Survival of Primary Intracranial Plasmablastic Lymphoma: Case Report and Review of the Literature

BACKGROUND

Primary intracranial plasmablastic lymphoma (PIPBL) is a rare malignant tumor.

CASE DESCRIPTION

We present a case of PIPBL in a 32-year-old man who complained of a progressive growing, painful mass on the right parieto-occipital part of head. Computed tomography and magnetic resonance imaging revealed a homogeneously enhanced mass with partial bone destruction. The patient underwent total resection and cranioplasty in one stage. Histopathologic examination showed large tumor cells with immunoblast-like nuclei. Immunohistochemical staining displayed CD38(+), CD138(+), Mum-1(+), CD20(-), and PAX-5(-). The patient received chemotherapy. The patient has survived more than 3.5 years after operation, with follow-up. We also review the clinical data, molecular pathologic traits, treatment, and prognosis of additional 6 cases with PIPBL in the literature.

CONCLUSIONS

This study provides important clinical information for the diagnosis and treatment of PIPBL.

A rare presentation of plasmablastic lymphoma as cutaneous nodules in an immunocompromised patient

Plasmablastic lymphoma is a rare entity accounting for around 2.7% of all AIDS-related lymphomas. The oral cavity and gastrointestinal tract are the most common sites involved. We report a case of a 34-year-old HIV-positive woman with a rare presentation of cutaneous nodules all over the body. Due to overwhelming tumour burden, she developed tumour lysis syndrome during her hospital stay and succumbed to the illness.

Clinical and pathological aspects of human immunodeficiency virus-associated plasmablastic lymphoma: analysis of 24 cases

Plasmablastic lymphoma (PBL) is a rare AIDS-related malignancy with a poor prognosis. Little is known about this entity, and no standard treatment regimen has been defined. To establish an adequate treatment strategy, we investigated 24 cases of PBL arising in human immunodeficiency virus-positive individuals. Most of the patients were in the AIDS stage, with a median CD4 count of 67.5/µL. Lymph nodes (58 %), gastrointestinal tract (42 %), bone marrow (39 %), oral cavity (38 %), and CNS (18 %) were the most commonly involved sites. Histology findings for the following were positive at varying rates, as follows: CD10 (56 %); CD30 (39 %); CD38 (87 %); MUM-1 (91 %); CD138 (79 %); EBER (91 %); and LMP-1 (18 %). There was a marked increase in patients in 2011-12, and the cases found in that period appeared to be more aggressive, showing a higher rate of advanced-stage PBL. Fourteen cases were treated with CHOP, while the others were treated with more intensive regimens, including bortezomib and hematopoietic stem cell transplantation. The overall median survival time was 15 months. A CD4 count of >100/µL at diagnosis and attaining complete remission in the first-line chemotherapy were associated with better outcomes (P = 0.027 and 0.0016, respectively). Host immune status and chemosensitivity are associated with improved prognosis in PBL.

Diagnostic and therapeutic challenges of EBV-positive mucocutaneous ulcer: a case report and systematic review of the literature

BACKGROUND

Epstein-Barr virus-positive mucocutaneous ulcer (EBVMCU) is a recently recognized B cell lymphoproliferative disorder that is driven by latent EBV infection and causes discrete ulcerations in the oropharynx, gastrointestinal tract, and skin. Local attenuation of immunosurveillance associated with iatrogenic immunosuppressant use, primary immunodeficiency, or age-associated immunosenescence has been implicated as a predisposing factor. This disorder is likely under reported, as it was only first defined in 2010 and shares histological features with other B-cell proliferative neoplasms. The first case series that described EBVMCU suggested that EBVMCU is generally self-limited and is likely to resolve without treatment. Since that publication, additional cases have been reported that describe a more heterogeneous clinical course, often requiring aggressive therapy. We now systematically review all published cases of EBVMCU and detail a case of aggressive and progressive EBVMCU, including diagnostic and management challenges, as well as successful treatment with radiation therapy.

CASE PRESENTATION

A forty-nine year old woman presented with painful and debilitating multifocal oral EBVMCU that initially responded to four weekly doses of rituximab. Her disease relapsed within 3 months and continued to progress and cause significant morbidity. She was successfully treated with local external beam radiation therapy of 30 Gy in 15 fractions, with duration of response of at least 6 months.

CONCLUSIONS

We suggest that although many patients with EBVMCU experience a self-limited course, for others EBVMCU can be a debilitating, persistent disorder that requires aggressive therapy to prevent disease progression. CD20- and CD30-directed antibody therapy, local radiation therapy, local surgical excision, systemic chemotherapy, and a combination of these therapies have all been successfully used to treat EBVMCU with high rates of durable clinical remission. As EBVMCU is not currently included in the 2008 WHO classification of lymphoproliferative disorders and no evidence-based guidelines or expert opinions have been proposed to guide therapy, this case report and systematic review provides a foundation on which to guide therapeutic decisions.

Plasmablastic Lymphoma Mimicking Acute Pancreatitis

Background. Plasmablastic lymphoma (PBL) is a rare B-cell neoplasm. It predominantly occurs in the oral cavity of human immunodeficiency virus (HIV)-positive patients and exhibits a highly aggressive clinical behavior. Case Presentation. We describe an unusual case of a 37-year-old HIV-positive male who presented with acute pancreatitis secondary to multiple peripancreatic masses compressing the pancreas. Histopathological examination of the lesions showed diffuse and cohesive pattern of large B-cells resembling immunoblasts or plasmablasts. The neoplastic cells were positive for BOB1 and MUM1, partially positive for CD79a, and negative for CD20, CD56, CD138, CD3, CD5, AE1/AE3, and HHV8. Epstein-Barr virus-encoded RNA in situ hybridization was positive. These features were consistent with PBL. The patient was initiated on cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy, demonstrating a striking response. Conclusion. To our research, this is the first report of PBL with the initial presentation of acute pancreatitis. The findings in this case suggest that PBL should be included in the differential diagnosis of pancreatic and peripancreatic tumors.

Hematolymphoid Lesions of the Sinonasal Tract

Hematolymphoid neoplasms of the sinonasal tract are rare and the majority represents non-Hodgkin lymphomas. This review will focus on morphologic, immunophenotypic, and genetic characteristics of the most common types of non-Hodgkin lymphoma, namely diffuse large B cell lymphoma and extranodal natural killer/T-cell lymphoma, nasal type, but also include the discussion of less frequent other hematolymphoid entities, such as extranodal plasmacytomas and Rosai-Dorfman disease.

Plasmablastic Lymphoma: A Review of Current Knowledge and Future Directions

Plasmablastic lymphoma (PBL) is an aggressive subtype of non-Hodgkin's lymphoma (NHL), which frequently arises in the oral cavity of human immunodeficiency virus (HIV) infected patients. PBL shows diffuse proliferation of large neoplastic cells resembling B-immunoblasts/plasmablasts, or with plasmacytic features and an immunophenotype of plasma cells. PBL remains a diagnostic challenge due to its peculiar morphology and an immunohistochemical profile similar to plasma cell myeloma (PCM). PBL is also a therapeutic challenge with a clinical course characterized by a high rate of relapse and death. There is no standard chemotherapy protocol for treatment of PBL. Cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or CHOP-like regimens have been the backbone while more intensive regimens such as cyclophosphamide, vincristine, doxorubicin, high-dose methotrexate/ifosfamide, etoposide, high-dose cytarabine (CODOX-M/IVAC), or dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin (DA-EPOCH) are possible options. Recently, a few studies have reported the potential value of the proteasome inhibitor bortezomib and thalidomide in PBL patients. The introduction of genes encoding artificial receptors called chimeric antigen receptors (CARs) and CAR-modified T cells targeted to the B cell-specific CD19 antigen have demonstrated promising results in multiple early clinical trials. The aim of this paper is to review the recent advances in epidemiology; pathophysiology; clinical, pathologic, and molecular characteristics; therapy; and outcome in patients with PBL.

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.

Plasmablastic Lymphoma of Small Intestine: A Rare Case Report with Review of Literature

Plasmablastic lymphoma (PBL) is a rare aggressive neoplasm characterized by diffuse proliferation of large neoplastic cells with plasma cell immunophenotype. Cell of origin of PBL is believed to be a postgerminal center B-lymphocyte or plasmablast. The malignant cells in PBL usually do not express CD20 (B cell marker) but do express markers of plasmacytic differentiation, such as CD38, CD138, or MUM1/IRF4, akin to plasma cell myeloma (PCM). PBL though originally described in the oral cavity, has now been found to occur in extraoral locations as well. Small intestine as a site of PBL has been described very rarely. PBL remains a diagnostic challenge given its overlapping morphologic and immunophenotypic features with other high grade lymphomas and PCM. We report a rare case of PBL of small intestine in a 48 years old HIV infected male patient. To the best of our knowledge this represents sixth case in the literature described in this location. An unusual rare pattern of CD138 positivity by IHC is also reported along with extensive review of literature of PBL in extraoral locations.

Plasmoblastic lymphoma as cause of perianal fistula: a case report and literature review

We report the case of a 33-year-old HIV-infected man who presented with a recurrent, nonhealing perianal fistula. After multiple benign biopsies, the diagnosis of plasmablastic lymphoma (PBL) eventually was made. The patient underwent chemotherapy and radiation with a complete response. Perianal fistulas are frequent in HIV-positive patients, but PBL as a cause is extremely rare. This often delays the diagnosis and treatment of this highly aggressive disease. We review the literature and discuss the pitfalls in the diagnosis and management of the disease.

Burkitt's lymphoma masquerading as appendicitis--two case reports and review of the literature

Two cases of Burkitt’s lymphoma masquerading as appendicitis are reported herein. The diagnoses were made post-operatively from the appendix specimen in one case and from an ileocecal resection specimen for cecal fistula complicating an appendicectomy in the second case. These cases highlight the importance of routine histological examination of appendicectomy specimens.

Pediatric plasmablastic lymphoma: a clinicopathologic study

Plasmablastic lymphoma (PBL) is reported rarely in children. To date, 10 cases are documented in the English-language literature. This study, based on 13 biopsies from 11 HIV-positive children (9 males, 2 females), documents the clinicopathologic features of PBL. The CD4 count ranged from 9 to 800 cells/mm(3). All biopsies demonstrated exclusive plasmablastic morphology; CD20 immunonegativity; and VS38c, EMA, CD31, MUM-1, CD45, and CD79a immunopositivity. B-cell monoclonality was confirmed in all biopsies. Of 3 biopsies subjected to FISH investigation, 2 had a t(8,14) translocation. Nine patients with follow-up details were treated exclusively with HAART (highly active antiretroviral therapy) or with combinations of HAART, chemotherapy, and radiotherapy. Seven patients died. PBL histomorphology, disease stage, and treatment modalities employed were not predictive of outcome. The survival of 2 stage 4 patients for 3 and 8 years each, managed on HAART, chemotherapy, and radiotherapy, however, may justify a role for combined therapeutic modalities for PBL.

HHV-8-positive and EBV-positive intravascular lymphoma: an unusual presentation of extracavitary primary effusion lymphoma

Intravascular lymphomas are rare and aggressive hematolymphoid tumors. Here, we describe a human herpesvirus type-8 (HHV-8)/Kaposi sarcoma-associated herpesvirus-positive and Epstein-Barr virus (EBV)-positive intravascular lymphoma. The patient was a 59-year-old human immunodeficiency virus-positive man who presented with diarrhea, abdominal pain, fevers, night sweats, and weight loss. Radiographic studies of the abdomen and pelvis revealed numerous subcentimeter nodules within the subcutaneous fat that lacked connection to the skin. An excisional biopsy demonstrated large atypical cells within vessels in the deep subcutaneous fat, and many of the vessels contained extensive organizing thrombi. The atypical cells lacked strong expression of most B-cell markers but were positive for MUM-1 and showed partial expression of several T-cell markers. An immunohistochemical stain for HHV-8 and an in situ hybridization for EBV were both positive in the neoplastic cells. The disease had a rapidly progressive and fatal course. This lymphoma appears to represent an entirely intravascular form of primary effusion lymphoma and highlights the propensity for HHV-8 and EBV-positive lymphoid neoplasms to show aberrant expression of T-cell markers, illustrates the utility of skin biopsies for the diagnosis of intravascular lymphoma, and suggests that biopsies to evaluate for intravascular lymphoma should be relatively deep and include subcutaneous fat.

A case of plasmablastic lymphoma diagnosed on liquid-based pap test

Primary gynecological lymphomas are rare and difficult to diagnose with Pap test. Herein, we report an uncommon case of plasmablastic lymphoma in a 61-year-old female with human immunodeficiency virus that presents with vaginal bleeding. The following case report shows the cytological features on liquid-based Pap test, cell block studies with diagnostic immunohistochemistry, discussion of the diagnostic difficulties, and a literature review.