Plasmablastic lymphoma in pediatric patients: clinicopathologic study of three cases

Clinicopathologic Spectrum of Pediatric Posttransplant Lymphoproliferative Diseases Following Solid Organ Transplant

CONTEXT.—

Posttransplant lymphoproliferative disorder (PTLD) remains a significant complication in pediatric patients undergoing solid organ transplant (SOT). The majority involve Epstein-Barr virus (EBV)-driven CD20+ B-cell proliferations, which respond to reduction of immunosuppression and anti-CD20-directed immunotherapy. Owing to the low overall incidence, prospective studies of pediatric PTLD are scarce, leading to a lack of comprehensive understanding of this disorder in pediatric populations. This review aims to bridge this knowledge gap by providing a comprehensive analysis of the clinical, morphologic, and molecular genetic features of PTLD in children, adolescents, and young adults after SOT.

OBJECTIVE.—

To examine the clinical features, pathogenesis, and classification of pediatric PTLDs after SOT.

DATA SOURCES.—

Personal experiences and published works in PubMed.

CONCLUSIONS.—

PTLD includes a broad and heterogeneous spectrum of disorders, ranging from nonmalignant lymphoproliferations to lymphomas. While most pediatric PTLDs are EBV+, an increasing number of EBV- PTLDs have been recognized. The pathologic classification of PTLDs has evolved in recent decades, reflecting advancements in understanding the underlying pathobiology. Nevertheless, there remains a great need for further research to elucidate the biology, identify patients at higher risk for aggressive disease, and establish optimal treatment strategies for relapsed/refractory disease.

Plasmablastic Lymphoma. A State-of-the-Art Review: Part 1-Epidemiology, Pathogenesis, Clinicopathologic Characteristics, Differential Diagnosis, Prognostic Factors, and Special Populations

This two-part review aims to present a current and comprehensive understanding of the diagnosis and management of plasmablastic lymphoma. The first section, as presented in this paper, reviews epidemiology, etiology, clinicopathological characteristics, differential diagnosis, prognostic variables, and the impact of plasmablastic lymphoma on specific populations. Plasmablastic lymphoma (PBL) is a rare and aggressive form of lymphoma. Previous and modern studies have demonstrated a significant association between the human immunodeficiency virus (HIV) and the development of the disease. The limited occurrence of PBL contributes to a need for a more comprehensive understanding of the molecular mechanisms involved in its etiology. Consequently, the diagnostic procedure for PBL poses a significant difficulty. Among the group of CD20-negative large B-cell lymphomas, PBL can be correctly diagnosed by identifying its exact clinical characteristics, anatomical location, and morphological characteristics. PBL cells do not express CD20 or PAX5 but possess plasmacytic differentiation markers such as CD38, CD138, MUM1/IRF4, Blimp1, and XBP1. PBL must be distinguished from other B-cell malignancies that lack the CD20 marker, including primary effusion lymphoma, anaplastic lymphoma kinase-positive large B-cell lymphoma, and large B-cell lymphoma (LBCL). This condition is frequently associated with infections caused by the Epstein-Barr virus and genetic alterations involving the MYC gene. Despite advances in our comprehension of this disease, the prognosis remains dismal, resulting in a low overall survival rate, although recent reports suggest an apparent tendency towards substantial improvement.

Plasmablastic lymphoma: An update

Plasmablastic lymphoma (PBL) is a highly aggressive B cell non-Hodgkin lymphoma frequently associated with immunosuppression, particularly human immunodeficiency virus (HIV) infection. Although PBL is rare globally, South Africa has a high burden of HIV infection leading to a higher incidence of PBL in the region. Laboratory features in PBL may overlap with plasmablastic myeloma and other large B cell lymphomas with plasmablastic or immunoblastic morphology leading to diagnostic dilemmas. There are, however, pertinent distinguishing laboratory features in PBL such as a plasma cell immunophenotype with MYC overexpression, expression of Epstein-Barr virus-encoded small RNAs and lack of anaplastic lymphoma kinase (ALK) expression. This review aims to provide a summary of current knowledge in PBL, focusing on the epidemiology, pathophysiology, laboratory diagnosis and clinical management.

Tibial Plasmablastic Lymphoma in a HIV-Negative Child: A Novel Extraoral Localisation

Plasmablastic lymphoma is an aggressive, high-grade non-Hodgkin lymphoma predominantly seen in HIV-infected individuals. Alongside a strong correlation with HIV, PBL can manifest in immunocompromised HIV-negative patients. A rare case of PBL in an immunocompetent and otherwise healthy child presented to Indus Hospital & Health Network (IHHN), Karachi, Pakistan. The patient had complaints of swelling and pain in the right leg and was referred from a city in Interior Sindh. Histopathological analysis revealed sheets and aggregates of neoplasm replacing bone marrow interspersed with sclerotic bony fragments. Large, monomorphic, multinucleated neoplastic cells containing abundant cytoplasm and scattered pleomorphic cells were also noted, leading to the diagnosis of tibial plasmablastic lymphoma. A FAB/LMB96 group C chemotherapy regimen for aggressive and high-risk cancer was administered with a marked improvement in clinical symptoms.

Epstein-Barr virus-positive mucocutaneous ulcer, plasmablastic type, associated with nodal CD4+ angioimmunoblastic T-cell lymphoma and generalised pruritus: a self-limiting lymphoproliferative disorder resembling cutaneous plasmablastic lymphoma

A woman in her 80s reported of generalised pruritus, which was treated with phototherapy and steroid administration. Two months after onset, lymph node biopsy revealed CD4+ angioimmunoblastic T-cell lymphoma with systemic superficial nodal involvement. Intractable prurigo was judged as T-cell lymphoma related. After effective chemotherapy (7 months later), skin nodules appeared multifocally, including on the lip, thumb and lower leg. The biopsied infiltrative lesion on the right lower leg microscopically revealed subcutaneous growth of atypical plasmablasts with nearly 100% Ki-67 labelling and Epstein-Barr virus (EBV)-encoded small nuclear RNA positivity. Plasmablastic lymphoma (CD45/CD19/CD38/CD138/MUM1+, CD20/CD79a/PAX5-) was suspected. Immunoglobulin light-chain restriction and nuclear expression of c-myc protein were undetectable, and the ulcers were spontaneously epithelialised by the cessation of steroid administration. After 10 months, non-progressive prurigos persisted on the extremities, but without regrowth of nodal T-cell lymphoma and cutaneous lymphoproliferative lesion. Reactive nature of the EBV-induced mucocutaneous plasmablastic growth (EBV-positive mucocutaneous ulcer, plasmablastic type) is discussed.

A Rare Case of HIV-Associated Plasmablastic Lymphoma of Anal Canal

Plasmablastic lymphoma, an acquired immunodeficiency syndrome defining malignancy, is a subtype of diffuse large B-cell lymphoma. It is classically described in the oral cavity, the extraoral presentation being rare. Owing to its rarity and aggressiveness, plasmablastic lymphoma poses a diagnostic and therapeutic challenge to the treating physician. A 40-year-old male, recently diagnosed with HIV infection, presented with bleeding per rectum and spurious diarrhea. Examination revealed proliferative growth in the anal canal. Biopsy of the lesion was diagnostic of plasmablastic lymphoma. Computed tomography and magnetic resonance imaging were done to stage the lesion and assess the local extent, respectively. A multidisciplinary board discussion was done, and the patient was instituted on antiretroviral therapy and chemoradiotherapy. Following six cycles of chemotherapy and 25 fractions of radiotherapy, he achieved complete remission.

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.

There Are No Magic Bullets in Hematopathology: Even Immunostains for CD20 and CD3 Can Get You Into Trouble

Immunohistochemistry is a powerful tool for the diagnosis and subclassification of hematolymphoid neoplasms. However, the expression of certain markers is not always as expected, and unusual patterns of staining can lead to misdiagnosis. CD20 and CD3 are our most commonly used markers for identification of B cells and T cells, respectively, and they almost always yield reliable, specific staining. This discussion focuses on diagnostic pitfalls related to the use of immunohistochemistry for CD20 and CD3 in hematopathology, and specifically on diagnostic challenges that arise when (1) CD20 is not expressed in B-cell lymphomas, when (2) CD20 is expressed in plasma cell neoplasms and T-cell lymphomas, and when (3) CD3 is expressed in B-cell lymphomas and Hodgkin lymphoma.

Head and neck lymphomas: A 20-year review in an Oral Pathology Unit, Johannesburg, South Africa, a country with the highest global incidence of HIV/AIDS

OBJECTIVES

Non-Hodgkin lymphoma occurs with increasing frequency in HIV/AIDS. As South Africa has the highest incidence of HIV/AIDS worldwide, an epidemiologic study of this nature provides insight into head and neck lymphomas in a defined South African population. This retrospective review evaluated frequency and clinico-pathologic characteristics of patients diagnosed with head and neck lymphoma at the Oral Pathology Department, University of Witwatersrand between 1993 and 2012.

MATERIALS AND METHODS

Histopathology reports of patients with head and neck lymphomas (n=504) were reviewed. Demographic (age, gender), clinical (site and size of tumour), laboratory and histological parameters were recorded.

RESULTS

There were 504 patients with head and neck lymphomas. The mean age was 40.4years. The male:female ratio was 1.1:1. The cervical lymph node was the most common anatomic site (115 cases) and the maxilla (60 cases) the most common extranodal site. Plasmablastic lymphoma (159 cases) was the most common histologic subtype, seen more frequently as a result of its strong association with HIV/AIDS. The most common Hodgkin's lymphoma was the nodular sclerosing variant (21 cases). Of the head and neck lymphomas in patients with a known HIV status, 56% had plasmablastic lymphoma, 43.9% diffuse large B cell lymphoma and 25% Burkitt lymphoma.

CONCLUSION

There is an increase in head and neck lymphoma frequency, contrary to that found in Western countries. The high HIV prevalence in certain lymphomas provides strong indication of the role of HIV/AIDS in pathogenesis of lymphomas. This study serves as a baseline for future studies, especially in South Africa.

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.

Let's face it - 13 unusual causes of facial masses in children

Facial swelling is commonly encountered in paediatric patients and is typically related to an underlying infection. The spectrum of possible causes, however, is wide, and includes traumatic, inflammatory, nutritional and neoplastic aetiologies. In this pictorial essay we present 13 examples of rare conditions selected from a total of 136 MRI examinations performed at our institution between April 2007 and May 2013. These include HIV-associated malignancies such as a case of plasmablastic lymphoma, parotid gland tumours including a parotid hamartoma, rare congenital lesions such as a thyroid fetiform teratoma, and infective lesions including tuberculosis of the mandible. In many cases, only minimal information could be gleaned from the literature, particularly with regard to imaging findings. An analysis of the spectrum of masses and specific clinical presentations allowed for the construction of a diagnostic flowchart which may serve to assist in unusual cases.

TEACHING POINTS

• Facial swelling is commonly encountered in paediatrics, with a wide spectrum of possible aetiologies. • MRI is the favoured imaging modality for accurate assessment. • Facial swelling is typically infectious in nature, but includes various benign and malignant causes. • This pictorial essay presents 13 examples of rare conditions with corresponding imaging.

Current knowledge on HIV-associated Plasmablastic Lymphoma

HIV-associated PBL is an AIDS-defining cancer, classified by WHO as a distinct entity of aggressive DLBCL. To date less than 250 cases have been published, of them 17 are pediatric. The pathogenesis of this rare disease is related to immunodeficiency, chronic immune stimulation and EBV. Clinically is a rapid growing destructive disease mainly involving the oral cavity even if extraoral and extranodal sites are not infrequent. The diagnosis requires tissue mass or lymph node biopsy and core needle or fine needle biopsy is acceptable only for difficult access sites. Classically immunophenotype is CD45, CD20, CD79a negative and CD38, CD138, MUM1 positive, EBER and KI67 is >80%. Regarding the therapy, standard treatment is, usually, CHOP or CHOP-like regimens while more intensive regimens as CODOX-M/IVAC or DA-EPOCH are possible options. Use of cART is recommended during chemotherapy, keeping in mind the possible overlapping toxicities. Rituximab is not useful for this CD20 negative disease and CNS prophylaxis is mandatory. Intensification with ABMT in CR1 may be considered for fit patients. For refractory/relapsed patients, therapy is, usually, considered palliative, however, in chemo-sensitive disease, intensification + ABMT or new drugs as Bortezomib may be considered. Factors affecting outcome are achieving complete remission, PS, clinical stage, MYC, IPI score. Reported median PFS ranges between 6-7 months and median OS ranges between 11-13 months. Long term survivors are reported but mostly in pediatric patients. Finally, due to the scarcity of data on this subtype of NHL we suggest that the diagnosis and the management of HIV-positive PBL patients should be performed in specialized centers.

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.