Plasmablastic lymphoma: current perspectives

Abstract

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.

Extraoral plasmablastic lymphomas in a high human immunodeficiency virus endemic area

“…The Ki67 PI is much lower in both immunocompetent DLBCLs (±40%) and extramedullary PCTs (<40%) . Other features concur in distinguishing PBLs from extramedullary PCTs: the presence of EBER signals, which are almost always positive in HIV‐associated PBL, and variable in HIV‐associated DLBCL, but rare in extramedullary PCTs; and the presence of MYC rearrangements in nearly 50% of PBLs and rarely in extramedullary PCTs . Unlike PBL, extramedullary PCT is not known to be associated with HIV infection; it occurs in immunocompetent individuals .…”

“…42 Other features concur in distinguishing PBLs from extramedullary PCTs: the presence of EBER signals, which are almost always positive in HIV-associated PBL, and variable in HIVassociated DLBCL, but rare in extramedullary PCTs; and the presence of MYC rearrangements in nearly 50% of PBLs and rarely in extramedullary PCTs. 43 Unlike PBL, extramedullary PCT is not known to be associated with HIV infection; it occurs in immunocompetent individuals. 44 The lack of typical plasma cell morphology and the absence of lytic bone lesions, hypercalcaemia and serum M-protein in patients made plasma cell disorder in our cohort unlikely.…”

Diffuse large B-cell lymphoma variants: an update

“…These neoplasms occur commonly in the setting of immunodeficiency, especially human immunodeficiency virus (HIV) infection, and represent approximately 3% of HIVrelated lymphomas. [22][23][24] These neoplasms also can occur in patients following allogeneic transplant and in patients with other forms of immunodeficiency. In addition, a subset of elderly patients may develop PBL, presumably attributable to physiological immunosenescence.…”

Unilateral Maxillary Sinus Plasmablastic Lymphoma in an Immunocompetent Patient. An Unusual Occurrence Report and Literature Review

“…4 Common sites for PBL commonly presents in extranodal regions, commonly confined to the oral cavity mucosa and gingiva, followed by digestive tract and skin. 5 The incidence of PBL is estimated in 2% to 12% of all HIV-associated lymphomas; however, the incidence in the immunocompetent population is still unknown due to its rarity with only a handful of PBL cases reported to date in immunocompetent individuals. 3 To date, PBL has been only partially characterized based on sporadic reports describing the condition, almost exclusively in immunodeficient patients with predominance of extranodal disease involving the oral cavity.…”