Aggressive presentation of plasmablastic myeloma

Daratumumab, Lenalidomide, and Dexamethasone (DRD), an Active Regimen in the Treatment of Immunosuppression-Associated Plasmablastic Lymphoma (PBL) in the Setting of Gorham’s Lymphangiomatosis: Review of the Literature

Characterized by an aggressive course with a poor overall survival due to treatment refractoriness, plasmablastic lymphoma (PBL) is a rare variant of diffuse large cell B cell lymphoma. Gorham’s lymphangiomatosis or Gorham–Stout disease (GSD) is a rare skeletal condition of unknown etiology characterized by progressive bone loss and nonmalignant proliferation of vascular and lymphatic channels within the affected bone. Neither disease has a standard of care. We present a 23-year-old HIV-negative woman with GSD, managed medically with octreotide and sirolimus, who developed PBL. After progressing on V-EPOCH (bortezomib, etoposide, vincristine, cyclophosphamide, doxorubicin, and prednisone), she was treated with daratumumab, lenalidomide, and dexamethasone (DRD) therapy and achieved complete remission after two cycles with progression after eight cycles. This is a report of treatment of PBL with DRD therapy. Clinical investigations of the DRD regimen in PBL in conjunction with other agents to improve both depth and durability of response are warranted.

Plasmablastic myeloma in Taiwan frequently presents with extramedullary and extranodal mass mimicking plasmablastic lymphoma

Plasmablastic myeloma (PBM) is a blastic morphologic variant of plasma cell myeloma with less favorable prognosis than those with non-blastic morphology. PBM is rare, without clear-cut definition and detailed clinicopathologic features in the literature. PBM may mimic plasmablastic lymphoma (PBL) as they share nearly identical morphology and immunophenotype. Using the criteria of ≥ 30% plasmablasts in tissue sections, we retrospectively recruited PBM cases and analyzed their clinical, imaging, and pathologic findings, with emphasis on extramedullary involvement. We performed immunohistochemistry, in situ hybridization for Epstein-Barr virus (EBER), and fluorescence in situ hybridization (FISH) for lymphoma- and myeloma-associated genetic alterations. Of the 25 recruited cases, 15 (60%) had extramedullary involvement, which occurred as initial presentation in nine cases. The most common extramedullary sites were soft tissue and/or skin (10/15, 67%), followed by pleural effusion, the lungs, and lymph nodes. Immunohistochemically, tumor cells expressed MYC (74%; 17/23), CD56 (56%; 14/25), and cyclin D1 (16%; 4/25), while CD117 was all negative (n = 25). Of the 20 cases stained with p53, four (20%) cases were diffusely positive, and the remaining 16 cases showed a heterogeneous pattern. EBER was negative in all 24 cases examined. Of the 13 cases examined with FISH, the genetic aberrations identified included del(13q14)(92%; 12/13), gain of chromosome 1q (90%; 9/10), loss of chromosome 1p (60%; 6/10), IGH-FGFR3 reciprocal translocation (23%; 3/13), rearranged MYC (15%; 2/13), and rearranged CCND1 (8%; 1/13), while there were no cases with TP53 deletion (n = 10) or rearrangement of BCL2 (n = 13) or BCL6 (n = 13). The prognosis was dismal regardless of the presence or absence of extramedullary involvement. In conclusion, PBM in Taiwan frequently presented as extramedullary and extranodal lesions, particularly in soft tissue and/or skin, mimicking PBL. FISH for targeted genetic alterations such as del(13q14), gain of chromosome 1q, loss of chromosome 1p, and IGH-FGFR3 might be helpful for the differential diagnoses. Larger studies are warranted to investigate the genetic alterations between PBM and PBL.

Plasmablastic Lymphoma or Plasmablastic Myeloma: A Case of Post-Transplant Lymphoproliferative Disorder

Plasmablastic lymphomas and plasmablastic myelomas are malignancies with overlapping clinical and pathological features which pose a diagnostic dilemma and are known to be aggressive with a poor outcome. CD38 is a common immunophenotypic maker for both these malignancies and provides a rationale for using daratumumab-based regimes. We describe a 57-year-old male with a history of end-stage renal disease who underwent a deceased-donor renal transplant maintained on chronic immunosuppression who presented with ascites and was found to have abdominal adenopathy and a lytic lesion in the humerus and diagnosed with a post-transplant lymphoproliferative disorder with features intermediate between plasmablastic lymphoma and plasmablastic myeloma. The patient was subsequently treated with a daratumumab-based regime with an excellent response. This case highlights a rare scenario that poses a diagnostic and therapeutic challenge. As there is no standard of care for the treatment of both these malignancies, this case report also describes the use of daratumumab with a good long-term outcome, especially when the pathological distinction between the two entities is difficult.

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.

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.