Survival outcomes of patients with primary plasma cell leukemia (pPCL) treated with novel agents

• Published in: Cancer Vol. 125; no. 3; pp. 416 - 423
• Main Authors: Mina, Roberto, Joseph, Nisha S., Kaufman, Jonathan L., Gupta, Vikas A., Heffner, Leonard T., Hofmeister, Craig C., Boise, Lawrence H., Dhodapkar, Madhav V., Gleason, Charise, Nooka, Ajay K., Lonial, Sagar
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.02.2019
• Subjects: Autografts; autologous stem cell transplantation (ASCT); Bortezomib; Cancer; chemotherapy; Disease control; Immunomodulation; Leukemia; Maintenance; Medical prognosis; Myeloma; novel agents; Oncology; Patients; Plasma; Plasma cell leukemia; Plasma cells; primary plasma cell leukemia (pPCL); Prognosis; Stem cell transplantation; Stem cells; Survival; Thalidomide; Therapy; Transplantation; primary plasma cell leukemia (pPCL); autologous stem cell transplantation (ASCT); chemotherapy; maintenance; novel agents
• ISSN: 0008-543X; 1097-0142
• DOI: 10.1002/cncr.31718

Background Primary plasma cell leukemia (pPCL) is an aggressive plasma cell disorder characterized by circulating plasma cells and a poor prognosis. Although patients who have pPCL benefit from the use of stem cell transplantation (SCT) and novel agents, their prognosis remains inferior to that of patients who have myeloma. Methods This was a retrospective analysis of 38 consecutive patients with pPCL who were diagnosed between October 2005 and July 2016 and were registered in the Winship Cancer Institute of Emory University database. Baseline characteristics as well as data about treatment and survival outcomes were collected. Results The median patient age at diagnosis was 58 years. All patients received a bortezomib‐based induction regimen, and 92% received both bortezomib and an immunomodulatory drug (thalidomide or lenalidomide); in addition, 74% of patients underwent autologous SCT (ASCT), and 61% received maintenance therapy. The best response to first‐line therapy was a partial response or better in 87% of patients, and 45% had a complete response (CR). The achievement of ≥CR was a predictor for prolonged progression‐free survival (PFS) and overall survival (OS). The median PFS was 20 months, and the median OS was 33 months. PFS was prolonged in patients who underwent ASCT compared with those who did not undergo ASCT (25 vs 6 months; P = .004), and patients who received maintenance therapy after ASCT had prolonged median PFS (27 vs 11 months; P = .03) and a trend toward prolonged OS (median, 38 vs 22 months; P = .06) compared with those who did not receive maintenance therapy. Conclusions The current data support the use of regimens combining novel agents in the upfront treatment of patients with pPCL as well as the role of ASCT and maintenance therapy for long‐term disease control. This is the first extensive report in patients with primary plasma cell leukemia to demonstrate that proteasome inhibitors and immunomodulatory drugs, as both induction and maintenance treatment, result in prolonged survival. Patients with primary plasma cell leukemia who undergo autologous stem cell transplantation and receive continuous treatment have prolonged progression‐free and overall survival.