Plasmablastic lymphoma presenting as a ureteral polypoid mass

Plasmablastic Lymphoma Presenting as Extensive Peritoneal and Retroperitoneal Nodules in an HIV-Positive Patient

Plasmablastic lymphoma (PBL) is a rare but aggressive subtype of diffuse large B-cell lymphoma (DLBCL). The diagnosis of PBL is challenging as its features overlap with lymphoma and myeloma. The most common presentation involves the oral cavity/jaw in human immunodeficiency virus (HIV)-positive patients. It has also been reported in the gastrointestinal (GI) tract, lymph nodes, and soft tissues. Usually, if PBL involves the GI tract, it presents as a gut tumor mass. In this report, we present an HIV-positive patient with PBL presenting with multiple peritoneal nodules. To our knowledge, this is the first case of PBL presenting as multiple peritoneal and retroperitoneal nodules in an HIV-positive patient. This case emphasizes the rare presentation of a rare malignancy, difficulties in establishing a diagnosis, and the importance of proper and timely management.

Heterogeneity in the diagnosis of plasmablastic lymphoma, plasmablastic myeloma, and plasmablastic neoplasm: a scoping review

The diagnosis of plasmablastic lymphoma (PBL), plasmablastic myeloma (PBM), and plasmablastic neoplasm (PBN) may be arbitrary in some cases because these entities can be indistinct. We conducted this scoping review to investigate heterogeneity in diagnostic criteria used in previous studies and validate the diagnostic results of previous diagnostic algorithms and the algorithm we developed, which also includes diagnosis of PBN. Using the PRISMA Extension for Scoping Reviews, we analyzed literature published between September 2017 and April 2020. We identified a total of 163 cases (128 PBL, 32 PBM, and 3 PBN) from 77 case reports and 8 case series. We found that diagnostic criteria in the literature varied for PBL but were consistent for PBM. Our algorithm was the first attempt to include PBN in a complete structure. The results of the three diagnostic algorithms varied significantly. Hematologists and pathologists should pay more attention to the differential diagnosis of PBL, PBM, and PBN.

Light chain cast nephropathy caused by plasmablastic lymphoma of the bladder

Introduction: Plasmablastic lymphoma (PBL) is a rare form of B-cell lymphoma typically seen in patients with underlying immunosuppression such as HIV, autoimmune disease, and organ transplantation. PBL in HIV-positive patients usually originates from the gastrointestinal tract, with a predilection for the oral cavity. Bladder involvement by PBL is exceedingly rare, and cast nephropathy due to κ light chain-secreting PBL has not been reported previously. Case report: We report a patient who presented with acute kidney injury (AKI) in the setting of HIV, and was found to have a bladder tumor. Bladder pathology revealed a high-grade PBL with κ light chain restriction. Renal biopsy showed κ light chain cast nephropathy, presumably secondary to κ light chain-secreting PBL. Conclusion: Although the prognosis of PBL is poor, our patient recovered from AKI, achieved complete hematologic remission with chemotherapy, and underwent successful autologous stem cell transplant.