Combination of flow cytometry and functional imaging for monitoring of residual disease in myeloma.

The iliac crest is the sampling site for minimal residual disease (MRD) monitoring in multiple myeloma (MM). However, the disease distribution is often heterogeneous, and imaging can be used to complement MRD detection at a single site. We have investigated patients in complete remission (CR) during first-line or salvage therapy for whom MRD flow cytometry and the two imaging modalities positron emission tomography (PET) and diffusion-weighted magnetic resonance imaging (DW-MRI) were performed at the onset of CR. Residual focal lesions (FLs), detectable in 24% of first-line patients, were associated with short progression-free survival (PFS), with DW-MRI detecting disease in more patients. In some patients, FLs were only PET positive, indicating that the two approaches are complementary. Combining MRD and imaging improved prediction of outcome, with double-negative and double-positive features defining groups with excellent and dismal PFS, respectively. FLs were a rare event (12%) in first-line MRD-negative CR patients. In contrast, patients achieving an MRD-negative CR during salvage therapy frequently had FLs (50%). Multi-region sequencing and imaging in an MRD-negative patient showed persistence of spatially separated clones. In conclusion, we show that DW-MRI is a promising tool for monitoring residual disease that complements PET and should be combined with MRD.

Dose-dense and less dose-intense Total Therapy 5 for gene expression profiling-defined high-risk multiple myeloma.

Multiple myeloma (MM) is a heterogeneous disease with high-risk patients progressing rapidly despite treatment. Various definitions of high-risk MM are used and we reported that gene expression profile (GEP)-defined high risk was a major predictor of relapse. In spite of our best efforts, the majority of GEP70 high-risk patients relapse and we have noted higher relapse rates during drug-free intervals. This prompted us to explore the concept of less intense drug dosing with shorter intervals between courses with the aim of preventing inter-course relapse. Here we report the outcome of the Total Therapy 5 trial, where this concept was tested. This regimen effectively reduced early mortality and relapse but failed to improve progression-free survival and overall survival due to relapse early during maintenance.

The flow cytometry-defined light chain cytoplasmic immunoglobulin index and an associated 12-gene expression signature are independent prognostic factors in multiple myeloma.

As part of Total Therapy (TT) 3b, baseline marrow aspirates were subjected to two-color flow cytometry of nuclear DNA content and cytoplasmic immunoglobulin (DNA/CIG) as well as plasma cell gene expression profiling (GEP). DNA/CIG-derived parameters, GEP and standard clinical variables were examined for their effects on overall survival (OS) and progression-free survival (PFS). Among DNA/CIG parameters, the percentage of the light chain-restricted (LCR) cells and their cytoplasmic immunoglobulin index (CIg) were linked to poor outcome. In the absence of GEP data, low CIg <2.8, albumin <3.5 g/dl and age ⩾65 years were significantly associated with inferior OS and PFS. When GEP information was included, low CIg survived the model along with GEP70-defined high risk and low albumin. Low CIg was linked to beta-2-microglobulin >5.5 mg/l, a percentage of LCR cells exceeding 50%, C-reactive protein ⩾8 mg/l and GEP-derived high centrosome index. Further analysis revealed an association of low CIg with 12 gene probes implicated in cell cycle regulation, differentiation and drug transportation from which a risk score was developed in TT3b that held prognostic significance also in TT3a, TT2 and HOVON trials, thus validating its general applicability. Low CIg is a powerful new prognostic variable and has identified potentially drug-able targets.

Preemptive intravenous immunoglobulin allows safe and timely administration of antineoplastic therapies in patients with multiple myeloma and parvovirus B19 disease.

BACKGROUND: Parvovirus B19 (B19) disease is a rare cause of anemia in cancer patients and often goes unrecognized, causing delays in anticancer therapy. METHODS: A retrospective review was carried out of the records of patients with multiple myeloma who underwent melphalan-based autologous stem cell transplantation (MEL-ASCT) and developed B19 infection (January 2009-December 2011). Cases were defined by the presence of clinical and laboratory findings consistent with B19 disease in patients with repeatedly positive plasma quantitative polymerase chain reaction for parvovirus. RESULTS: Six patients qualified as cases; 5 presented with trilineage cytopenias (chronic in 1) and 1 with anemia later progressing to pancytopenia. Transfusion-dependent thrombocytopenia led to testing in 5 patients. Two of these patients also had manifestations of autoimmune disease. Therapy with intravenous immunoglobulin (IVIG) resulted in clinical and hematologic response in all; however, 1 patient, whose white blood cell counts and serum hemoglobin levels improved, required splenectomy for persistent thrombocytopenia. All patients required additional IVIG for recurrent B19 disease. Although viral load at diagnosis did not correlate with the severity of cytopenia, its decrease was associated with response during 17 of 20 evaluable episodes (P = 0.02). Preemptive IVIG allowed the safe administration of chemotherapy in 3 patients, including MEL-ASCT in 1. CONCLUSION: Parvovirus B19 can cause severe disease in myeloma patients including ASCT recipients. Thrombocytopenia - not anemia - was the leading presentation and may be associated with autoimmune conditions. Patients with unexplained cytopenias, particularly when prolonged, should undergo testing for circulating parvovirus. A reduction in viral load was associated with response to IVIG, although additional therapy was needed for recurrent disease. Most importantly, preemptive IVIG allowed for safe and timely administration of antineoplastic therapy in patients with ongoing B19 disease.

Prolonged prothrombin time correlates with serum monoclonal protein concentration in patients with plasma cell dyscrasia.

INTRODUCTION: Abnormal screening coagulation tests are frequently observed in asymptomatic patients with multiple myeloma and other plasma cell neoplasms. METHODS: Prothrombin time (PT), activated partial thromboplastin time (APTT) and fibrinogen activity were correlated with clinical history and disease parameters in patients referred to the Myeloma Institute for Research and Therapy. RESULTS: An isolated prolonged PT was the most common abnormal coagulation test (25%). Prolonged PT was more frequently observed in patients with multiple myeloma (n = 157) compared to MGUS patients (n = 34) or other diagnostic categories of plasma cell dyscrasia. There were no differences in age, gender, previous chemotherapy, or immunoglobulin isotype in patients with isolated prolonged PT (n = 62) compared to those with normal screening coagulation tests (n = 173). Fibrinogen activity was significantly lower in patients with prolonged PT; however, there was no correlation between fibrinogen activity and PT. Serum M protein concentrations were significantly greater in patients with prolonged PT and were positively correlated with PT. CONCLUSION: An association between disease severity and prolonged PT is suggested by our finding that patients with multiple myeloma were more likely to have prolonged PT than patients with other plasma cell neoplasms. Of the factors examined, the monoclonal protein level was significantly higher in patients with isolated prolonged PT and correlated with PT.

Activation of p38MAPK signaling cascade in a VSMC injury model: role of p38MAPK inhibitors in limiting VSMC proliferation.

INTRODUCTION: P38 mitogen-activated protein kinase (MAPK) has a crucial role in regulating signaling pathways implicated in the cellular events leading to restenosis. We examine p38MAPK activation in response to vascular cell injury, its biological effects and determine whether selective p38MAPK inhibitors, SB220025/SB203580, decrease vascular smooth muscle cell (VSMC) proliferation. METHODS: Human aortic VSMCs were cultured and wounds made on the monolayers to elicit mitogenic responses and induce p38MAPK activation. P38MAPK inhibitor pretreatment, at varying doses (1-100 microM) and treatment duration was used to block p38MAPK phosphorylation. Cytotoxicity, viability, proliferation and apoptosis were determined and expression of p38MAPK/phospho-p38MAPK was obtained by chemiluminiscent immunoblot analysis. RESULTS: Phosphorylation of p38MAPK depended on injury severity and was inhibited by both p38MAPK inhibitors, but not by SB202474, a specific antagonist of p38MAPK inhibitors. VSMCs treated with p38MAPK inhibitors showed a dose-dependent decrease in viable cell number, apoptosis and proliferation, reversing the deleterious effects of p38MAPK activation comparable to controls (p < 0.05). CONCLUSIONS: This wound injury model activates the p38MAPK-signaling cascade in VSMC and causes cell proliferation that can be abrogated by pre-incubation with p38MAPK selective synthetic inhibitors in a time and dose-dependent manner. SB220025 used here for the first time in VSMC reveals itself to be a stronger p38MAPK inhibitor than SB203580 and being a second generation inhibitor may be the preferred drug for novel therapeutic maneuvers.