Case Report of Transformation from Multiple Myeloma IgG KAPPA to Primary Plasma Cell Leukemia

Abstract

This case report describes a patient with multiple myeloma of IgG kappa isotype presenting as primary plasma cell leukemia (PCL). The authors first review PCL as a rare and aggressive entity, characterized by circulating plasma cells exceeding 20% and 2 × 10^9 cells/l, classified as primary when it appears de novo and secondary when it arises from relapsed or refractory multiple myeloma, and summarise its genetic abnormalities and clinical features. The patient, a 56-year-old woman with systemic arterial hypertension, presented with low back pain, lower-limb paresthesias, weight loss of approximately 29 kilograms, night sweats and fever. Investigations showed grade IV normocytic normochromic anemia, acute kidney injury, hypercalcemia, plasma cells on the peripheral blood smear and lytic lesions on tomography. Bone marrow aspirate showed more than 36% plasma cells, and peripheral blood flow cytometry identified a CD38+, CD138+ plasma cell population of 36.95%, compatible with multiple myeloma with primary plasma cell leukemia. She received platelet transfusions, management of hypercalcemia and acute kidney injury, and treatment with dexamethasone, lenalidomide and subcutaneous bortezomib (VRd), and was discharged to hematology outpatient follow-up. The authors note that the prognosis of primary PCL remains guarded, that consolidation with autologous hematopoietic stem cell transplantation should be considered in patients who achieve remission, and that close follow-up with periodic monitoring of biomarkers is essential.

Abstract prepared by the editorial office from the full text of the article; the authors did not supply one.