Rapid complete remission after one cycle of isatuximab-based quadruplet regimen in 1q21-positive primary plasma cell leukemia: a case report

Primary plasma cell leukemia (pPCL) is a rare and highly aggressive plasma cell malignancy. Patients often present with a large number of circulating plasma cells and extramedullary organ involvement at an early stage of the disease, frequently accompanied by severe infections and organ dysfunction, resulting in a poor overall prognosis. Current treatment strategies for pPCL are largely extrapolated from intensive induction regimens used for multiple myeloma; however, therapeutic outcomes remain