Frits van Rhee

Magnetic Resonance Imaging in Multiple Myeloma: Diagnostic and Clinical Implications

PURPOSE Magnetic resonance imaging (MRI) permits the detection of diffuse and focal bone marrow infiltration in the absence of osteopenia or focal osteolysis on standard metastatic bone surveys (MBSs). PATIENTS AND METHODS Both baseline MBS and MRI were available in 611 of 668 myeloma patients who were treated uniformly with a tandem autologous transplantation-based protocol and were evaluated to determine their respective merits for disease staging, response assessment, and outcome prediction. RESULTS MRI detected focal lesions (FLs) in 74% and MBS in 56% of imaged anatomic sites; 52% of 267 patients with normal MBS results and 20% of 160 with normal MRI results had FL on MRI and MBS, respectively. MRI- but not MBS-defined FL independently affected survival. Cytogenetic abnormalities (CAs) and more than seven FLs on MRI (MRI-FLs) distinguished three risk groups: 5-year survival was 76% in the absence of both more than seven MRI-FLs and CA (n = 276), 61% in the presence of one MRI-FL (n = 262), and 37% in the presence of both unfavorable parameters (n = 67). MRI-FL correlated with low albumin and elevated levels of C-reactive protein, lactate dehydrogenase, and creatinine, but did not correlate with age, beta-2-microglobulin, and CA. Resolution of MRI-FL, occurring in 60% of cases and not seen with MBS-defined FL, conferred superior survival. CONCLUSION MRI is a more powerful tool for detection of FLs than is MBS. MRI-FL number had independent prognostic implications; additionally, MRI-FL resolution identified a subgroup with superior survival. We therefore recommend that, in addition to MBS, MRI be used routinely for staging, prognosis, and response assessment in myeloma.

F18-fluorodeoxyglucose positron emission tomography in the context of other imaging techniques and prognostic factors in multiple myeloma

F18-fluorodeoxyglucose positron emission tomography (FDG-PET) is a powerful tool to investigate the role of tumor metabolic activity and its suppression by therapy for cancer survival. As part of Total Therapy 3 for newly diagnosed multiple myeloma, metastatic bone survey, magnetic resonance imaging, and FDG-PET scanning were evaluated in 239 untreated patients. All 3 imaging techniques showed correlations with prognostically relevant baseline parameters: the number of focal lesions (FLs), especially when FDG-avid by PET-computed tomography, was positively linked to high levels of beta-2-microglobulin, C-reactive protein, and lactate dehydrogenase; among gene expression profiling parameters, high-risk and proliferation-related parameters were positively and low-bone-disease molecular subtype inversely correlated with FL. The presence of more than 3 FDG-avid FLs, related to fundamental features of myeloma biology and genomics, was the leading independent parameter associated with inferior overall and event-free survival. Complete FDG suppression in FL before first transplantation conferred significantly better outcomes and was only opposed by gene expression profiling-defined high-risk status, which together accounted for approximately 50% of survival variability (R(2) test). Our results provide a rationale for testing the hypothesis that myeloma survival can be improved by altering treatment in patients in whom FDG suppression cannot be achieved after induction therapy.

CS1, a Potential New Therapeutic Antibody Target for the Treatment of Multiple Myeloma

Purpose: We generated a humanized antibody, HuLuc63, which specifically targets CS1 (CCND3 subset 1, CRACC, and SLAMF7), a cell surface glycoprotein not previously associated with multiple myeloma. To explore the therapeutic potential of HuLuc63 in multiple myeloma, we examined in detail the expression profile of CS1, the binding properties of HuLuc63 to normal and malignant cells, and the antimyeloma activity of HuLuc63 in preclinical models. Experimental Design: CS1 was analyzed by gene expression profiling and immunohistochemistry of multiple myeloma samples and numerous normal tissues. HuLuc63-mediated antimyeloma activity was tested in vitro in antibody-dependent cellular cytotoxicity (ADCC) assays and in vivo using the human OPM2 xenograft model in mice. Results: CS1 mRNA was expressed in >90% of 532 multiple myeloma cases, regardless of cytogenetic abnormalities. Anti-CS1 antibody staining of tissues showed strong staining of myeloma cells in all plasmacytomas and bone marrow biopsies. Flow cytometric analysis of patient samples using HuLuc63 showed specific staining of CD138+ myeloma cells, natural killer (NK), NK-like T cells, and CD8+ T cells, with no binding detected on hematopoietic CD34+ stem cells. HuLuc63 exhibited significant in vitro ADCC using primary myeloma cells as targets and both allogeneic and autologous NK cells as effectors. HuLuc63 exerted significant in vivo antitumor activity, which depended on efficient Fc-CD16 interaction as well as the presence of NK cells in the mice. Conclusions: These results suggest that HuLuc63 eliminates myeloma cells, at least in part, via NK-mediated ADCC and shows the therapeutic potential of targeting CS1 with HuLuc63 for the treatment of multiple myeloma.

Incorporating bortezomib into upfront treatment for multiple myeloma: early results of total therapy 3.

Total therapy 3 incorporated bortezomib into a melphalan‐based tandem transplant regimen for 303 newly diagnosed patients with myeloma. Induction chemotherapy prior to and consolidation chemotherapy after transplants each consisted of two cycles of VTD‐PACE (bortezomib, thalidomide, dexamethasone and 4‐d continuous infusions of cis‐platin, doxorubicin, cyclophosphamide, etoposide); 3‐year maintenance comprised monthly cycles of VTD in the first and TD in the remaining years. The median age was 59 years (age >64 years, 28%). A minimum of 20 × 106 CD34 cells/kg was collected in 87% of patients; 83% completed both transplants, and only 5% suffered a treatment‐related death. At 24 months, 83% had achieved near‐complete remission, which was sustained in 88% at 2 years from its onset. With a median follow‐up of 20 months, 2‐year estimates of event‐free and overall survival were 84% and 86% respectively. The 44 patients who experienced an event more often had a high‐risk gene array profile, cytogenetic abnormalities and indicators of high lactate dehydrogenase, beta‐2‐microglobulin, creatinine and International Staging System stage. Toxicities of grade > 2 included thrombo‐embolic events in 27% and peripheral neuropathy in 12%. Results of this phase‐2 study demonstrated that bortezomib could be safely combined with multi‐agent chemotherapy, effecting near‐complete remission status and 2‐year survival rates in more than 80% of patients.

Thalidomide arm of Total Therapy 2 improves complete remission duration and survival in myeloma patients with metaphase cytogenetic abnormalities.

Total Therapy 2 examined the clinical benefit of adding thalidomide up-front to a tandem transplant regimen for newly diagnosed patients with multiple myeloma. When initially reported with a median follow-up of 42 months, complete response rate and event-free survival were superior among the 323 patients randomized to thalidomide, whereas overall survival was indistinguishable from that of the 345 patients treated on the control arm. With further follow-up currently at a median of 72 months, survival plots segregated 5 years after initiation of therapy in favor of thalidomide (P = .09), reaching statistical significance for the one third of patients exhibiting cytogenetic abnormalities (CAs; P = .02), a well-recognized adverse prognostic feature. The duration of complete remission was also superior in the cohort presenting with CAs such that, at 7 years from onset of complete remission, 45% remained relapse-free as opposed to 20% on the control arm (P = .05). These observations were confirmed when examined by multivariate analysis demonstrating that thalidomide reduced the hazard of death by 41% among patients with CA-positive disease (P = .008). Because two thirds of patients without CAs have remained alive at 7 years, the presently emerging separation in favor of thalidomide may eventually reach statistical significance as well.

Deep vein thrombosis in patients with multiple myeloma treated with thalidomide and chemotherapy: effects of prophylactic and therapeutic anticoagulation

A group of 256 newly diagnosed myeloma patients were enrolled in a phase III study that included 4 monthly cycles of induction chemotherapy and tandem transplant. All patients were randomized to either receive or not receive thalidomide. A total of 221 patients (86%) received no prophylactic anticoagulation (cohort I); 35 patients received low dose coumadin (cohort II). The incidence of deep vein thrombosis (DVT) was significantly higher in the thalidomide arm hazard ratio: 4·5; P < 0·0001). As low dose coumadin (1 mg/d) failed to decrease thrombotic complications in 35 patients (cohort II), low molecular weight heparin (LMWH, enoxaparin 40 mg s.c. q.d.) was instituted as DVT prophylaxis in the thalidomide‐treated patients (n = 68) of the subsequent cohort (n = 130, cohort III). This intervention eliminated the difference in DVT incidence between the two arms (thalidomide and no thalidomide). Within cohorts I and II, 36 patients, in whom thalidomide was discontinued after experiencing a thrombotic episode during chemotherapy, subsequently resumed the drug on full anticoagulation; with a median follow‐up of 22 months, DVT recurred in four patients (11%). After completing induction and tandem transplantation, 55 patients were re‐exposed to thalidomide and chemotherapy during consolidation treatment. Thrombotic complications were observed in 4%. Our experience, although not based on a randomized study, suggests that the excess frequency of thrombosis in patients treated with chemotherapy and thalidomide can be safely reduced by the prophylactic use of LMWH. The rate of DVT recurrence observed in our study upon thalidomide resumption was sufficiently low to allow its continuation in patients who may benefit from this therapeutic intervention.

A phase 1, multicenter, open-label, dose escalation study of elotuzumab in patients with advanced multiple myeloma

This multicenter, first-in-human study evaluated the safety, tolerability, and pharmacokinetic and pharmacodynamic properties of the anti-CS1 monoclonal antibody elotuzumab. A standard 3 + 3 design was used to determine maximum tolerated dose; dose-limiting toxicities were assessed during cycle 1. Thirty-five patients with relapsed/refractory multiple myeloma were treated with intravenous elotuzumab at doses ranging from 0.5 to 20 mg/kg every 2 weeks. Patients who achieved at least stable disease after 4 treatments could receive another 4 treatments. No maximum tolerated dose was identified up to the maximum planned dose of 20 mg/kg. The most common adverse events, regardless of attribution, were cough, headache, back pain, fever, and chills. Adverse events were generally mild to moderate in severity, and adverse events attributed to study medication were primarily infusion-related. Plasma elotuzumab levels and terminal half-life increased with dose whereas clearance decreased, suggesting target-mediated clearance. CS1 on bone marrow-derived plasma cells was reliably saturated (≥ 95%) at the 10-mg/kg and 20-mg/kg dose levels. Using the European Group for Bone and Marrow Transplantation myeloma response criteria, 9 patients (26.5%) had stable disease. In summary, elotuzumab was generally well tolerated in this population, justifying further exploration of this agent in combination regimens.

Improved Outcome of Allogeneic Transplantation in High-Risk Multiple Myeloma Patients After Nonmyeloablative Conditioning

PURPOSE We present our experience with relapsed and recently diagnosed patients with high-risk multiple myeloma (MM) receiving immunosuppressive, nonmyeloablative melphalan (MEL)-based conditioning regimens (mini-allograft). PATIENTS AND METHODS Thirty-one MM patients received allografts from HLA-matched siblings (n = 25) or unrelated donors (n = 6) using a mini-allograft. Seventeen had progressive disease (PD) and 14 had responsive disease (RD) (six with primary RD and eight with responsive relapse). Thirty patients had received one (n = 13) or two or more (n = 17) prior autologous transplantations (ATs). Median age was 56 years (range, 38 to 69 years). Twenty-one patients had chromosome 13 abnormality. Two patients were hemodialysis dependent. Blood and bone marrow grafts were administered to 28 and three patients, respectively. Donor lymphocyte infusions were given to 18 patients either to attain full donor chimerism (n = 6) or to eradicate residual disease (n = 12). RESULTS By day 100, 25 (89%) of 28 patients were full donor chimeras, one was a mixed chimera, and two had autologous reconstitution. Acute graft-versus-host disease (GVHD) developed in 18 patients (58%), and 10 progressed to chronic GVHD (limited in six and extensive in four). At a median follow-up of 6 months, 19 (61%) of 31 patients achieved complete/near complete remission. Twelve patients (39%) have died: three of PD, three of early treatment-related mortality (TRM) (before day 100), and six of late TRM. Median overall survival (OS) was 15 months. At 1 year, there was a significantly longer event-free survival (86% v 31%, P =.01) and OS (86% v 48%, P =.04) when a mini-allograft was performed after one versus two or more prior ATs, respectively. When compared with historical MM controls (n = 93) receiving conventional allografts, early TRM was significantly lower (10% v 29%, P =.03), and OS at 1 year was better (71% v 45%; P =.08) in the mini-allograft MM patients. CONCLUSION Mini-allograft induced excellent disease control in MM patients with high-risk disease, but is still associated with a significant GVHD.

Superior results of Total Therapy 3 (2003-33) in gene expression profiling–defined low-risk multiple myeloma confirmed in subsequent trial 2006-66 with VRD maintenance

The Total Therapy 3 trial 2003-33 enrolled 303 newly diagnosed multiple myeloma patients and was noted to provide superior clinical outcomes compared with predecessor trial Total Therapy 2, especially in gene expression profiling (GEP)-defined low-risk disease. We report here on the results of successor trial 2006-66 with 177 patients, using bortezomib, lenalidomide, and dexamethasone maintenance for 3 years versus bortezomib, thalidomide, and dexamethasone in year 1 and thalidomide/dexamethasone in years 2 and 3 in the 2003-33 protocol. Overall survival (OS) and event-free survival (EFS) plots were super-imposable for the 2 trials, as were onset of complete response and complete response duration (CRD), regardless of GEP risk. GEP-defined high-risk designation, pertinent to 17% of patients, imparted inferior OS, EFS, and CRD in both protocols and, on multivariate analysis, was the sole adverse feature affecting OS, EFS, and CRD. Mathematical modeling of CRD in low-risk myeloma predicted a 55% cure fraction (P < .001). Despite more rapid onset and higher rate of CR than in other molecular subgroups, CRD was inferior in CCND1 without CD20 myeloma, resembling outcomes in MAF/MAFB and proliferation entities. The robustness of the GEP risk model should be exploited in clinical trials aimed at improving the notoriously poor outcome in high-risk disease.

Long-term outcome results of the first tandem autotransplant trial for multiple myeloma.

Total Therapy 1, the first tandem autotransplant trial for newly diagnosed patients with multiple myeloma, was designed to increase the frequency of complete response (CR) and thereby extend survival. With a median follow‐up of 12 years, 62 of 231 initially enrolled patients are alive (17% at 15 years); 31 remain event free (7% at 15 years) including 16 of 94 (41%) that initially achieved CR. Currently alive patients less frequently had cytogenetic abnormalities (CAs) at baseline (P = 0·002), postenrolment (P < 0·001) and at relapse (P = 0·004); elevations of serum C‐reactive protein (CRP) (P = 0·003) and lactate dehydrogenase (P = 0·029), anaemia (P = 0·029) and they more often completed two transplants within 12 months (P = 0·019). Postenrolment overall survival (OS) and event‐free survival (EFS) were superior in the absence of CA of the hypodiploidy or deletion 13 variety (P < 0·001 and 0·037 respectively) and in the presence of low CRP at baseline (P = 0·001 and 0·017 respectively). Postrelapse survival was longer in the absence of CA at relapse (P < 0·001), IgA isotype (P = 0·002), International Staging System stage 3 (P = 0·014), and when patients had two protocol transplants prior to relapse (P = 0·038). Ten‐year EFS and OS could be accomplished in 15% and 33% of patients, respectively, when all agents available in 1989, especially high‐dose melphalan, were applied together upfront for the management of myeloma.