Epstein-Barr virus-positive ileal extraosseous plasmacytoma containing plasmablastic lymphoma components with CD20-positive lymph node involvement

Epstein-Barr Virus-Positive Plasma Cell Neoplasms in Immunocompetent Patients: A Clinicopathological Study of 15 Cases from South China and Literature Review

Epstein-Barr virus (EBV)-positive plasma cell neoplasms (PCNs) in immunocompetent patients are a rare entity, the clinicopathological and prognostic features of which have not been well characterized. Fifteen cases of EBV-positive PCN arising in immunocompetent patients from south China were retrospectively analyzed, and an additional 44 cases from the literature were reviewed. The overall EBV-positive rate defined by EBV-encoded small RNAs (EBERs) in-situ hybridization of PCNs was 12.3% (15/122), and it was significantly higher in plasmacytoma (17.1%, 13/76) than in plasma cell myeloma/multiple myeloma (4.3%, 2/46; P=0.031). The age of the patients ranged from 17 to 79 years, with a median age of 56 years. There was a large preponderance of men, with a male-to-female ratio of 4:1. Solitary plasmacytoma of bone (23.8%, 5/21) had comparable EBV-encoded small RNAs-positive rates with extramedullary plasmacytoma arising in the upper respiratory tract (19.5%, 8/41; P=0.949). Anaplastic and classic cytologic appearance was observed in 61.5% (8/13) and 38.5% (5/13) of EBV-positive plasmacytomas, respectively. Cases with an anaplastic cytologic appearance had a significantly higher Ki-67 proliferation index than those with a classic cytologic appearance (median: 55% vs. 10%, P=0.001). In the combined cohorts, anaplastic/plasmablastic cytologic appearance was significantly more common in extramedullary plasmacytoma arising in the upper respiratory tract (72.0%, 18/25) than outside the upper respiratory tract (11.1%, 1/9; P=0.006). Among the 59 cases of EBV-positive PCN, survival data of 34 cases were available for analysis, including 30 cases of plasmacytoma and 4 cases of plasma cell myeloma/multiple myeloma. There was no statistically significant difference in overall survival between patients with EBV-positive plasmacytomas in the combined cohorts and EBV-negative plasmacytomas in the present cohort. The prevalence of EBV in PCN in immunocompetent patients varies according to histologic subtype and tumor location. Compared with EBV-negative cases, EBV-positive plasmacytomas tend to have an anaplastic/plasmablastic cytologic appearance. No significant impact of EBV infection on clinical outcomes is observed in the limited number of reported cases.

Potential effect of epigenetic drugs in the treatment of multiple-site extramedullary plasmacytoma involving the respiratory system: a case report and review of the literature

We report the case of a 23-year-old man with a medical history of idiopathic thrombocytopenic purpura (ITP) and newly diagnosed with the Epstein-Barr virus (EBV)-positive multiple-site extramedullary plasmacytoma (EMP), which involves the respiratory system. The patient was referred to our hospital because of progressive nasal congestion and nasal mass. Nasopharyngoscopy and bronchoscopy were performed. The biopsy pathological hematoxylin and eosin (HE) staining indicated plasma cell myeloma, and further immunohistochemistry CD99(+), CD79a(+), CD38(+), MUM-1(+), and Lambda(+) confirmed the diagnosis. The patient's bone marrow was normal, and hypercalcemia, renal insufficiency, anemia, evident bone lesions were not observed. Serum immunoglobulin quantification, serum protein electrophoresis, and blood and urine light chain quantification were all within the normal range. The serum immunofixation electrophoresis was negative, and the serum-free light chain was normal. These results could rule out multiple myeloma (MM) and prove to be EMP involving the nasal cavity, main bronchus, lung, and left hip. No desired effect was achieved after receiving PAD (bortezomib, adriamycin, and dexamethasone) and VRD (bortezomib, lenalidomide, and dexamethasone) treatments. Even if the tumor was remarkably relieved after receiving the 2-course CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) regimen, secondary resistance to CHOP unfortunately occurred in this case. We attempted to apply epigenetic therapy in the treatment of refractory multiple EMP. Although no complete remission (CR) was achieved, the maximum standard uptake value (SUVmax) in tumor lesions was significantly lower than before, and the patient's symptoms significantly improved. The patient tolerated decitabine and chidamide. We speculated that epigenetic drugs have potential effect in the treatment of multiple-site EMP.

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.

Epstein-Barr virus-positive plasmacytoma in immunocompetent patients: a diagnostic dilemma

By literature review, plasmacytomas arising in immunocompetent patients are rarely associated with Epstein-Barr virus (EBV) infection. EBV-positive plasmacytoma can cause a diagnostic dilemma as it may morphologically and phenotypically overlap with a clinically aggressive plasmablastic lymphoma (PBL). We reported the clinicopathologic and immunophenotypic findings of four patients with EBV-positive plasmacytomas (three cases of extramedullary plasmacytomas, one case of solitary plasmacytoma of bone) with immunocompetent status. These tumors were characterized by a diffuse proliferation of mature appearing plasma cells, which were diffusely positive for EBV encoded RNA (EBER) by in situ hybridization. All the four patients were alive with no evidence of disease at last follow-up.

CD3+ CD56+ EBER1+ atypical extraosseous plasmacytoma of the nasal cavity

We present a case of atypical extraosseous plasmacytoma (EP) with a plasmablastic morphology and CD3⁺ CD56⁺ Epstein-Barr virus-encoded RNA-1 (EBER1)⁺ phenotypes of the nasal cavity. A 51-year-old male attended a local hospital with a tumor located in his left nasal cavity that was histologically diagnosed as extranodal NK/T cell lymphoma, nasal type. We reviewed the specimens and re-biopsied the tumor, and confirmed that the tumor was positive for CD3, CD56, and EBER1; however, the tumor showed a plasmablastic morphology without necrosis and angiocentricity, and was positive for CD138, but negative for CD20 and PAX5. Given a plasmablastic morphology and EBER1 positivity, but a relatively low Ki67 index (30%), we diagnosed the case as atypical EP. The CHOP regimen was administered and complete remission achieved. This case indicated that EP should be considered as a differential diagnosis even when a tumor shows large cell morphology and is positive for CD3, CD56, and EBER1.

Solitary Extramedullary Plasmacytoma of the Cricoid Cartilage-Case Report

Solitary plasmacytoma (SP) is an extremely rare form of hematologic malignancy that can be classified as solitary bone plasmacytoma or solitary extramedullary plasmacytoma. Here, we report a patient who presented with progressive shortness of breath and foreign body sensation in his throat. Fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) demonstrated an abnormal FDG-avid soft tissue mass arising from the larynx involving the cricoid cartilage without additional suspicious lesions. Histology revealed an abundance of plasma cells; immunohistochemistry was positive for CD138 expression and lambda chains, and negative for CD20. Comprehensive imaging studies and panendoscopy of the ENT tract confirmed solitary disease involvement. Following additional systemic work-up, a diagnosis of extramedullary plasmacytoma was rendered. The patient underwent definitive radiotherapy using intensity-modulated radiation therapy (total dose of 46 Gy, divided in 23 fractions of 200 cGy). Serial PET/CT showed the stepwise resolution of abnormal FDG uptake and resolution of the cricoid cartilage lesion. With 22 months of follow-up, the patient remains free of disease. We describe the rare case of SP presenting as a FDG-avid hypermetabolic soft tissue mass in the cricoid cartilage, which should be considered in the differential diagnosis of laryngeal tumors. Of note, SP is radiosensitive; favorable outcome can be expected once treated with doses of 40–50 Gy. FDG PET/CT is helpful in diagnosis and response assessment for this disease.

Recent Advances in Aggressive Large B-cell Lymphomas: A Comprehensive Review

Diffuse large B-cell lymphoma (DLBCL) is an aggressive disease with considerable heterogeneity reflected in the 2008 World Health Organization classification. In recent years, genome-wide assessment of genetic and epigenetic alterations has shed light upon distinct molecular subsets linked to dysregulation of specific genes or pathways. Besides fostering our knowledge regarding the molecular complexity of DLBCL types, these studies have unraveled previously unappreciated genetic lesions, which may be exploited for prognostic and therapeutic purposes. Following the last World Health Organization classification, we have witnessed the emergence of new variants of specific DLBCL entities, such as CD30 DLBCL, human immunodeficiency virus-related and age-related variants of plasmablastic lymphoma, and EBV DLBCL arising in young patients. In this review, we will present an update on the clinical, pathologic, and molecular features of DLBCL incorporating recently gained information with respect to their pathobiology and prognosis. We will emphasize the distinctive features of newly described or emerging variants and highlight advances in our understanding of entities presenting a diagnostic challenge, such as T-cell/histiocyte-rich large B-cell lmphoma and unclassifiable large B-cell lymphomas. Furthermore, we will discuss recent advances in the genomic characterization of DLBCL, as they may relate to prognostication and tailored therapeutic intervention. The information presented in this review derives from English language publications appearing in PubMed throughout December 2015. For a complete outline of this paper, please visit: http://links.lww.com/PAP/A12.

Epstein-Barr virus-positive plasmacytoma in immunocompetent patients

AIMS

Extramedullary plasmacytomas are often localized, clinically indolent neoplasms, and affected patients usually respond to radiation therapy or limited cycles of chemotherapy. In contrast, plasmablastic lymphomas are clinically aggressive neoplasms composed of immunoblastic or plasmablastic cells and associated with more mature plasma cells in some cases. Patients with plasmablastic lymphoma usually have a poor prognosis despite aggressive chemotherapy. Evidence of Epstein-Barr virus (EBV) infection is uncommon in plasmacytoma, but common in plasmablastic lymphoma, and is therefore helpful in differential diagnosis. The aim of this study is to describe four cases of plasmacytoma arising in immunocompetent individuals that were diffusely positive for Epstein-Barr virus-encoded small RNA as shown by in-situ hybridization.

METHODS AND RESULTS

We describe the clinicopathological and immunophenotypic findings of four EBV-positive plasmacytomas arising in immunocompetent patients. These tumours were characterized by diffuse proliferation of mature-appearing plasma cells intermixed with a briskly reactive, CD8-positive, TIA-1-positive cytotoxic T-cell infiltrate. Long-term follow-up was available for all patients, and all were alive and free of disease at last follow-up (median 43.4 months).

CONCLUSIONS

We suggest the term EBV-positive plasmacytoma in immunocompetent patients for these lesions. It is essential to distinguish these tumours from plasmablastic lymphoma, as the latter diagnosis is associated with a much poorer prognosis, and patients require much more aggressive therapy.

Expect the Unexpected: Report of a Case of Pediatric Pharyngeal Extraosseous Plasmacytoma with Tumefactive Amyloidosis ("Amyloidoma") and a Review of the Literature

We report a rare case of localized pharyngeal tumefactive amyloidosis caused by extraosseous plasmacytoma in a 12 year-old girl who presented with otalgia, sore throat and blood stained sputum. The tumor was predominantly composed of amyloid with a limited component of well-differentiated neoplastic plasma cells, which were monoclonal (kappa restricted) on light chain in-situ hybridization. The amyloid deposits were positive for kappa immunoglobulin light chain on immunohistochemistry. The patient was treated with a combination of surgery and radiotherapy. Follow-up at 1 year showed no evidence of recurrence or progression.