Plasma Cell Leukemia: Case Series From a Tertiary Center with Review of Literature

Abstract

Plasma cell leukemia is an unusual manifestation of multiple myeloma, reported to occur in 2% of newly diagnosed patients. It may either present at the time of diagnosis (primary) or evolve as a late feature in the course of multiple myeloma (secondary). Most clinical signs of myeloma are observed in plasma cell leukemia, although osteolytic lesions and bone pain are less frequent and lymphadenopathy, organomegaly and renal failure are more often present. The immunophenotype of plasma cell leukemia differs typically from that of myeloma by lack of aberrant CD56 expression. An abnormal karyotype is more frequently found in plasma cell leukemia and there is higher incidence of unfavourable cytogenetics. Plasma cell leukemia is an aggressive disease, characterized by a fulminant course and a short survival. We are reporting cases of this rare condition which presented at our center over 3 years along with review of literature.

Acquired del(9)(p22.3) in a primary plasma cell leukemia

“…In addition plasma cells in PCL frequently lack CD56 antigen, which has been considered important in anchoring plasma cells to bone marrow stroma [12]. Immunophenotypic expression is similar in PCL and MM for CD38, CD138, CD2, CD3, CD6, CD10, CD13 and CD15 [3]. The phenotypic differences do not allow a complete discrimination between PCL and MM, but help to explain the differences in survival, since CD56 expression has been associated with good prognosis while CD20 expression has been associated with a shorter survival [13].…”

“…), thrombocytopenia, anemia, hypercalcemia and impaired renal function [3]. PCL displays multiple adverse prognostic indicators at presentation such as elevated LDH, elevated ß2-microglobulin, hypercalcemia, high percentage of Bence-Jones proteinemia, and extramedullary involvement [13].…”

“…Clinically, patients with primary PCL have a higher incidence of hepatosplenomegaly and lymphadenopathy, and less lytic bone lesions [3]. Prognostic indexes such as B2-microglobulin, plasma cells in S-phase, proteinuria, calcium levels, LDH and renal function usually are found to be significantly higher in PCL than in MM [2].…”

“…Due to the low frequency of this entity, most publications on PCL are based on case reports, only a few series exist with more than 20 patients in the medical literature, and difficulties remain in defining the biological, clinical, and prognostic features of the disease [2,3]. …”

A case of CD138-/CD19+/CD4+ IgD plasma cell leukemia

“…It is a particularly aggressive form of plasma cell dyscrasia that makes up 2 to 4% of all multiple myeloma (MM) cases 1,2 . As per the World Health Organization, diagnosis is made by the presence of more than 20% of plasma cells in peripheral blood smear or a plasma cell count of over 2000cells/µL 3 .…”