Changing paradigms in the treatment of multiple myeloma

Characterization and prognostic features of secondary acute myeloid leukemia in survivors of multiple myeloma

This large population-based study determined the epidemiology and outcomes of secondary acute myeloid leukemia (sAML) in multiple myeloma (MM) survivors using the Surveillance Epidemiology and End Results (SEER) Research Plus 9 database. To identify 64,753 cases of MM which included 136 cases with sAML; these patients were juxtaposed with patients with de novo AML from the same database. Younger MM patients who received chemotherapy (ChT) had a higher sAML risk. The novel agent era saw a decreased sAML incidence (0.15% vs. 0.26%) and shorter latency period (median: 56 vs. 66 months, P=0.031). Compared to de novo AML, sAML patients were older (median age 69 vs. 68 years, P=0.027), less likely to receive ChT (51.9% vs. 67.4%, P<0.001), and had inferior overall survival (OS) (median OS: 2 vs. 5 months, P<0.001). Multivariate Cox regression revealed that younger diagnosis age, diagnosis after 2003, and ChT were associated with prolonged OS in sAML patients. Clinicians should be aware of the sAML risk in younger, intensively-treated MM patients. Given the poor sAML prognosis compared to de novo AML, clinical trials of novel therapies based on age, geriatric assessment, and cytogenetic features are warranted.

Clinical outcomes and complications of surgical interventions for multiple myeloma lesions in the extremities and pelvis: A retrospective clinical study

OBJECTIVE

This study aimed to assess the pain and functional status of patients who underwent various surgical interventions for the stabilization of selected multiple myeloma (MM) lesions in the extremities and pelvis and to investigate the rate of complications requiring reintervention.

METHODS

Patients with MM who underwent various surgical interventions for the extremity or pelvic lesions were retrospectively reviewed. Change in the pain intensity was assessed using visual analogous scale (VAS) preoperatively, at the time of discharge, and at the final follow-up. Functional status was assessed using the musculoskeletal tumor society (MSTS) scoring system for both upper and lower extremities preoperatively and at the final follow-up. Postoperative complications requiring reintervention, including dislocation, loss of fixation/aseptic loosening of prosthesis, mechanical insufficiency, periprosthetic fracture, infection, or progression of the local disease, were recorded.

RESULTS

A total of 49 (20 men and 29 women) previously (23) or newly (26) diagnosed patients with a mean age of 60.8±18.2 years were included in this study. Of these, 6 patients underwent multiple surgeries for different skeletal sites; in total, 57 procedures were performed. The mean follow-up was 47.7±21.63 months. The lesions were localized to the humerus (19), radius (1), pelvis (4), femur (30), and tibia (3). The surgical indications included therapy-refractory pain for 17 patients and pathological fractures due to progression of pre-existing lesions for 12 patients or newly diagnosed lesions with extensive bone destruction at initial presentation for 28 patients. Surgical procedures included prosthetic reconstruction in 32 patients, cement-augmented osteosynthesis in 9, and closed intramedullary nailing in 16. The mean VAS score decreased from 8.75±1.2 preoperatively to 3.21±1.56 at the time of discharge and 1.2±0.42 at the final follow-up. Although a significant decrease was detected between the preoperative and postoperative VAS scores at the time of discharge (p=0.0001), the decrease between the time of discharge and the final follow-up was statistically insignificant (p=0.086). The mean MSTS score significantly improved from 9.1%±6.4% (range: 0%-40%) preoperatively to 76%±14.9% (range: 40%-93.3%) at the final follow-up (p=0.0001). Significantly higher MSTS scores were obtained in the upper extremity than lower extremity/pelvis (p=0.04) and in isolated diaphyseal involvement than metaphyseal or articular involvement (p=0.032). A total of 11 complications requiring reintervention (19.2%) were observed, which included dislocation (3.5%), loss of fixation (5.2%), mechanical insufficiency (3.5%), infection (5.2%), and local tumor progression (1.7%). The rate of complications requiring reintervention was lower but statistically insignificant in the upper extremity (5%; 1/20) than lower extremity/pelvis (27%; 10/37) (p=0.076) and in isolated diaphyseal involvement (6.2%; 1/16) than metaphyseal or articular involvement (24.3%; 10/41) (p=0.079).

CONCLUSION

Although different types of surgeries can achieve pain relief and good function in different anatomical localizations, better functional results with lower complication rates may be obtained following surgical management of MM lesions in the upper extremities and in diaphyseal localizations.

LEVEL OF EVIDENCE

Level IV, Therapeutic Study.

Strategies to improve patient-reported outcome completion rates in longitudinal studies

Purpose

The quality of patient-reported outcome (PRO) data can be compromised by non-response (NR) to scheduled questionnaires, particularly if reasons for NR are related to health problems, which may lead to unintended bias. The aim was to investigate whether electronic reminders and real-time monitoring improve PRO completion rate.

Methods

The population-based study “Quality of life in Danish multiple myeloma patients” is a longitudinal, multicentre study with consecutive inclusion of treatment-demanding newly diagnosed or relapsed patients with multiple myeloma. Education of study nurses in the avoidance of NR, electronic reminders, 7-day response windows and real-time monitoring of NR were integrated in the study. Patients complete PRO assessments at study entry and at 12 follow-up time points using electronic or paper questionnaires. The effect of the electronic reminders and real-time monitoring were investigated by comparison of proportions of completed questionnaires before and after each intervention.

Results

The first 271 included patients were analysed; of those, 249 (85%) chose electronic questionnaires. Eighty-four percent of the 1441 scheduled PRO assessments were completed within the 7-day response window and 11% after real-time monitoring, achieving a final PRO completion rate of 95%. A significant higher proportion of uncompleted questionnaires were completed after the patients had received the electronic reminder and after real-time monitoring.

Conclusions

Electronic reminders and real-time monitoring contributed to a very high completion rate in the study. To increase the quality of PRO data, we propose integrating these strategies in PRO studies, however highlighting that an increase in staff resources is required for implementation.

Local radiotherapy for palliation in multiple myeloma patients with symptomatic bone lesions

Purpose

To evaluate the clinical outcomes of symptomatic bone lesions in patients with multiple myeloma (MM) who received local radiotherapy (LRT).

Materials and Methods

Fifty-one patients with 87 symptomatic bone lesions treated via LRT were analyzed. LRT was delivered at a median total dose of 21 Gy (range, 12 to 40 Gy) in a median of 7 fractions (range, 4 to 20 fractions). The clinical outcomes of LRT and the factors affecting treatment response were assessed.

Results

After a median follow-up time of 66.7 weeks, symptom relief was achieved for 85 of 87 lesions (97.7%). The median time to symptom relief was 7 days from the start of LRT (range, 1 to 67 days). The duration of in-field failure-free survival ranged from 1.1 to 450.9 weeks (median, 66.7 weeks). The radiation dose or use of previous and concurrent chemotherapy was not significantly associated with in-field failure for LRT (p = 0.354, 0.758, and 0.758, respectively).

Conclusion

Symptomatic bone lesions in patients with MM can be successfully treated with LRT. A higher radiation dose or the use of concurrent chemotherapy may not influence the in-field disease control. A relatively low radiation dose could achieve remission of symptoms in patients with MM.

Current role of radiation therapy for multiple myeloma

Background: Radiation therapy (RT) is a treatment modality traditionally used in patients with multiple myeloma (MM), but little is known regarding the role and effectiveness of RT in the era of novel agents, i.e., immunomodulatory drugs and proteasome inhibitors.

Methods: We retrospectively reviewed data from 449 consecutive MM patients seen at our institute in 2010–2012 to assess indications for RT as well as its effectiveness. Pain response was scored similarly to RTOG 0631 and used the Numerical Rating Pain Scale.

Results: Among 442 evaluable patients, 149 (34%) patients and 262 sites received RT. The most common indication for RT was palliation of bone pain (n = 109, 42%), followed by prevention/treatment of pathological fractures (n = 73, 28%), spinal cord compression (n = 26, 10%), and involvement of vital organs/extramedullary disease (n = 25, 10%). Of the 55 patients evaluable for pain relief, complete and partial responses were obtained in 76.4 and 7.2%, respectively. Prior RT did not significantly decrease the median number of peripheral blood stem cells collected for autologous transplant, even when prior RT was given to both the spine and pelvis. Inadequacy of stem cell collection for autologous stem cell transplant (ASCT) was not significantly different and it occurred in 9 and 15% of patients receiving no RT and spine/pelvic RT, respectively. None of the three cases of therapy-induced acute myelogenous leukemia/MDS occurred in the RT group.

Conclusion: Despite the introduction of novel effective agents in the treatment of MM, RT remains a major therapeutic component for the management in 34% of patients, and it effectively provides pain relief while not interfering with successful peripheral blood stem cell collection for ASCT.

Improved response rates with bortezomib in relapsed or refractory multiple myeloma: an observational study in Chinese patients

INTRODUCTION

Bortezomib, a novel proteasome inhibitor, is approved for the treatment of relapsed multiple myeloma (MM). Efficacy and safety of bortezomib is well known; however, it was necessary to validate the data in patients with different ethnic backgrounds. The efficacy and safety of bortezomib was assessed in patients from China with relapsed/refractory MM in a real-world scenario.

METHODS

This prospective, non-interventional, observational study enrolled both male and female Chinese patients, aged ≥18 years and diagnosed with relapsed or refractory MM. Administration of intravenous bortezomib at 1.3 mg/m2 was recommended twice a week for 2 weeks (days 1, 4, 8 and 11), followed by a 10-day rest period (maximum of 8 cycles) and a follow-up every 12 weeks for 3 years. Efficacy assessments included best response, objective response rate (ORR), time to response, duration of response, and overall survival. Safety was also assessed.

RESULTS

A total of 517 patients were enrolled with a median age of 58.7 years. Patients predominantly had immunoglobulin G type (46.2%) and stage III (47.8%) myeloma. Overall, 202 (42.3%) patients had partial response as best response, ORR was 88.9% and the proportion of patients exhibiting complete response was 24.7%. The median time to response observed was 27 (21-40) days. Median time to progression was 415 days and median overall survival was 475 days. Thrombocytopenia (14.4%) was the most common adverse event.

CONCLUSION

Bortezomib demonstrated clinical response in majority of patients and was well tolerated in this observational study in Chinese patients with relapsed/refractory MM.

Targeting the biophysical properties of the myeloma initiating cell niches: a pharmaceutical synergism analysis using multi-scale agent-based modeling

Multiple myeloma, the second most common hematological cancer, is currently incurable due to refractory disease relapse and development of multiple drug resistance. We and others recently established the biophysical model that myeloma initiating (stem) cells (MICs) trigger the stiffening of their niches via SDF-1/CXCR4 paracrine; The stiffened niches then promote the colonogenesis of MICs and protect them from drug treatment. In this work we examined in silico the pharmaceutical potential of targeting MIC niche stiffness to facilitate cytotoxic chemotherapies. We first established a multi-scale agent-based model using the Markov Chain Monte Carlo approach to recapitulate the niche stiffness centric, pro-oncogenetic positive feedback loop between MICs and myeloma-associated bone marrow stromal cells (MBMSCs), and investigated the effects of such intercellular chemo-physical communications on myeloma development. Then we used AMD3100 (to interrupt the interactions between MICs and their stroma) and Bortezomib (a recently developed novel therapeutic agent) as representative drugs to examine if the biophysical properties of myeloma niches are drugable. Results showed that our model recaptured the key experimental observation that the MBMSCs were more sensitive to SDF-1 secreted by MICs, and provided stiffer niches for these initiating cells and promoted their proliferation and drug resistance. Drug synergism analysis suggested that AMD3100 treatment undermined the capability of MICs to modulate the bone marrow microenvironment, and thus re-sensitized myeloma to Bortezomib treatments. This work is also the first attempt to virtually visualize in 3D the dynamics of the bone marrow stiffness during myeloma development. In summary, we established a multi-scale model to facilitate the translation of the niche-stiffness centric myeloma model as well as experimental observations to possible clinical applications. We concluded that targeting the biophysical properties of stem cell niches is of high clinical potential since it may re-sensitize tumor initiating cells to chemotherapies and reduce risks of cancer relapse.

The role of histone deacetylase inhibitors in patients with relapsed/refractory multiple myeloma

Clinical outcomes for patients with multiple myeloma (MM) have improved substantially since the introduction of novel agents including the proteasome inhibitor bortezomib and the immunomodulatory drugs thalidomide and lenalidomide. However, most patients with MM eventually relapse, and prognosis remains poor among patients with relapsed and/or refractory disease. Combination therapy using agents with different mechanisms of action is emerging as an attractive treatment approach in oncology to increase efficacy and/or overcome resistance to standard treatment regimens. This review discusses unmet needs in the treatment of MM and the development of histone deacetylase inhibitors as a treatment modality for MM.

Overexpression of G protein-coupled receptor 5D in the bone marrow is associated with poor prognosis in patients with multiple myeloma

BACKGROUND

G protein-coupled receptor 5D (GPRC5D) is a novel surface receptor. As this new subtype of G protein-coupled receptors was discovered, little is known about the role of this gene.

MATERIALS AND METHODS

In this retrospective study, we investigated GPRC5D mRNA expression by real-time polymerase chain reaction (RT-PCR) in bone marrow (BM) of 48 patients with multiple myeloma (MM).

RESULTS

Highly variable levels of GPRC5D (median, 288; quartiles, 17-928) were detected in patients with MM, whereas only low expression was detected in normal tissues (median, 1; quartiles, 1-23). High mRNA expression of GPRC5D correlated positively with high plasma cell count in bone marrow (r = 0·64, P < 0·001), high β(2) -microglobulin (r = 0·42, P = 0·003) and poor-risk cytogenetics: deletion 13q14 (rb-1), P = 0·003; and 14q32 translocation t(4;14)(p16;q32), P = 0·029. GPRC5D mRNA expression showed a significant correlation with overall survival (P = 0·031). The estimated overall survival of patients expressing GPRC5D above or below the median of 288 was 43·9% vs. 70·2% at 48 months. Here, we report, for the first time, the association of GPRC5D expression and cancer.

CONCLUSIONS

Overexpression in poor-risk myeloma, low expression in normal tissues and cell surface expression identify GPRC5D as a potential novel cancer antigen. Our data demonstrate that GPRC5D is a prognostic factor in MM correlating with other major risk factors.

Prognostic impact of serum immunoglobulin heavy/light chain ratio in patients with multiple myeloma in complete remission after autologous stem cell transplantation

Immunoglobulin heavy/light chain (HLC) ratios were studied in 37 patients with multiple myeloma in complete remission after autologous hematopoietic stem cell transplantation. Increased IgAκ/IgAλ and IgMκ/IgMλ ratios were associated with longer progression-free survival (P = .006 and .01, respectively). A statistical trend toward a longer overall survival was also observed for the IgAκ/IgAλ ratio (P = .068). Considering the original immunoglobulin isotype, our results indicate that an increased κ/λ ratio of the uninvolved isotype is associated with longer progression-free survival and overall survival. This is the first report demonstrating the association between the HLC ratio and sustained complete remission in patients with multiple myeloma. Our results suggest that the HLC ratio is a surrogate marker of immune recovery after myeloablative transplantation, rather than as a marker of minimal residual disease.