Continuous lenalidomide treatment after bortezomib-melphalan-prednisolone therapy for newly diagnosed multiple myeloma.

These are the results of phase II study of bortezomib-melphalan-prednisolone (VMP) induction therapy followed by lenalidomide-dexamethasone (Rd) consolidation and lenalidomide maintenance in transplant-ineligible patients with newly diagnosed multiple myeloma (NDMM). The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), overall response rates (ORRs), and safety. Eighty-three eligible patients were enrolled between October 2012 and August 2014. The median PFS was 28.0 months (95% CI 19.6-36.7) and the median OS was 55.3 months (95% CI 51.6-NA). Among the patients who received lenalidomide maintenance therapy, median PFS was significantly improved in patients who had achieved a very good partial response (VGPR) or better (41.8 vs 20.7 months, p = 0.0070). As the best response, the rates of partial response or better were 85.5% comprising stringent complete response (sCR, 21.7%), complete response (CR, 10.8%), VGPR (18.1%), and partial response (PR, 34.9%). The most frequently observed grade 3 or higher adverse events during the VMP therapy were anemia (28.9%), neutropenia (15.6%), thrombocytopenia (6.0%), and peripheral neuropathy (2.4%). The most frequently observed grade 3 or higher adverse events during the Rd therapy were anemia (3.5%), neutropenia (1.8%), and skin rush (5.3%). The most frequently observed grade 3 or higher adverse events during lenalidomide maintenance therapy were anemia (7.4%) and neutropenia (24.1%). Thus, VMP induction therapy followed by Rd consolidation and lenalidomide maintenance is considered a well-tolerated and effective regimen in transplant-ineligible NDMM. This trial is registered with UMIN-CTR with the identification number UMIN000009042.

WT1 mRNA level in peripheral blood is a sensitive biomarker for monitoring minimal residual disease in acute myeloid leukemia.

The Wilms' tumor gene 1 (WT1) encodes a transcription factor that is involved in normal cellular development and cell survival. WT1 mRNA is overexpressed in the minimal residual disease (MRD) of patients with hematopoietic malignancy patients, particularly acute myeloid leukemia (AML). MRD represents the condition with the low levels of leukemia cells in the bone marrow and is known as a sign of recurrence. In hematopoietic malignancies, definition of remission is based on the lack of MRD at submicroscopic level. Between December 2005 and June 2008, we started to measure WT1 mRNA levels in the peripheral blood (PB) from patients by quantitative real-time PCR in Aomori Prefectural Central Hospital. Three hundreds and eight samples from 95 patients were evaluated. The patients included AML (55 patients), acute lymphoblastic leukemia (11), myelodysplastic syndrome (20), malignant lymphoma (5), chronic myeloid leukemia (1), prostatic carcinoma (1), and leukopenia (2). Among the 55 AML patients, 21 patients were pretreated with remission induction therapy. In the clinical course of 21 patients, timely therapeutic approaches could be started for relapse by the early detection of WT1 mRNA overexpression before the morphological findings were apparent. Monitoring WT1 mRNA is helpful to identify patients at high-risk relapse. High overall survival rate (71.2%, 15/21, median: 24.6 months, range 1.1-35.6 months) was achieved in 3 years. The overall survival rate of 34 post-treatment patients was 61.7% (median: 23.5 months, range 0.13-126.5 months after treatment start). In conclusion, the WT1 mRNA level is a sensitive biomarker for monitoring MRD.