Successful Intrathecal Chemotherapy Combined with Radiotherapy Followed by Pomalidomide and Low-Dose Dexamethasone Maintenance Therapy for a Primary Plasma Cell Leukemia Patient

Abstract

Primary plasma cell leukemia (PPCL) is a rare aggressive variant of plasma cell disorder and frequently presents with extramedullary disease. Central nervous system (CNS) involvement with PPCL has an extremely poor prognosis. We describe a 46-year-old man with PPCL treated with a combination of lenalidomide, bortezomib, and dexamethasone as induction therapy following upfront allogeneic stem cell transplantation (allo-SCT). Despite achieving a very good partial response, the patient suffered from an isolated CNS relapse 12 months after allo-SCT. He was immediately started on concurrent intrathecal chemotherapy (IT) and cranial irradiation (RT). Subsequently, pomalidomide and low-dose dexamethasone (Pd) were given as maintenance therapy. He has been without CNS recurrence for more than 18 months. Our case suggests that concurrent IT and RT followed by Pd maintenance therapy may be an effective option to control CNS relapse of PPCL after allo-SCT.

Plasma Cell Leukemia: Definition, Presentation, and Treatment

“…In a case report, a PCL patient with CNS relapse after allogenic SCT was successfully treated with cerebral radiation and intrathecal chemotherapy followed by pomalidomide and dexamethasone maintenance. At the time of reporting, the patient was still in remission after 18 months of follow-up [ 58 ]. In another case report, a patient with sPCL achieved normalization of hematological values and significant decrease in M-component after 4-month treatment combining low-dose dexamethasone and pomalidomide [ 59 ].…”

Successful eradication of leptomeningeal plasma cell disease

“…The prognosis of PCL involving the CNS is extremely poor with an overall survival ranging from 2 to 6 months [ 8 , 10 , 11 ]. Although there are currently no well-established treatment of leptomeningeal PCL, novel agents in CNS myeloma treatment are described [ 12 ], and pomalidomide and dexamethasone are described effective in a few case reports [ 13 , 14 ]. Moreover, long-term survival is described in some patients treated with the combination of CNS radiotherapy, multi-dosing intrathecal chemotherapy, and IMiD-containing therapy [ 8 , 15 ].…”