To date, the choice of therapy for an individual multiple myeloma patient has been based on clinical factors such as age and comorbidities. The widespread evolution, validation, and clinical ...utilization of molecular technologies, such as fluorescence in situ hybridization and next-generation sequencing has enabled the identification of a number of prognostic and predictive biomarkers for progression-free survival, overall survival, and treatment response. In this review, we argue that in order to continue to improve myeloma patient outcomes incorporating such biomarkers into the routine diagnostic workup of patients will allow for the use of personalized, biologically based treatments.
Based on the clinical features of myeloma and related malignancies of plasma cells, it has been possible to generate a model system of myeloma progression from a normal plasma cell through ...smouldering myeloma to myeloma and then plasma cell leukaemia. Using this model system we can study at which points the genetic alterations identified through whole-tumour molecular analyses function in the initiation and progression of myeloma. Further genetic complexity, such as intraclonal heterogeneity, and insights into the molecular evolution and intraclonal dynamics in this model system are crucial to our understandings of tumour progression, treatment resistance and the use of currently available and future treatments.
Understanding the profile of oncogene and tumor suppressor gene mutations with their interactions and impact on the prognosis of multiple myeloma (MM) can improve the definition of disease subsets ...and identify pathways important in disease pathobiology. Using integrated genomics of 1273 newly diagnosed patients with MM, we identified 63 driver genes, some of which are novel, including IDH1, IDH2, HUWE1, KLHL6, and PTPN11. Oncogene mutations are significantly more clonal than tumor suppressor mutations, indicating they may exert a bigger selective pressure. Patients with more driver gene abnormalities are associated with worse outcomes, as are identified mechanisms of genomic instability. Oncogenic dependencies were identified between mutations in driver genes, common regions of copy number change, and primary translocation and hyperdiploidy events. These dependencies included associations with t(4;14) and mutations in FGFR3, DIS3, and PRKD2; t(11;14) with mutations in CCND1 and IRF4; t(14;16) with mutations in MAF, BRAF, DIS3, and ATM; and hyperdiploidy with gain 11q, mutations in FAM46C, and MYC rearrangements. These associations indicate that the genomic landscape of myeloma is predetermined by the primary events upon which further dependencies are built, giving rise to a nonrandom accumulation of genetic hits. Understanding these dependencies may elucidate potential evolutionary patterns and lead to better treatment regimens.
•Using the largest set of patients with newly diagnosed myeloma, we identified 63 mutated driver genes.•We identified oncogenic dependencies, particularly relating to primary translocations, indicating a nonrandom accumulation of genetic hits.
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To investigate the prognostic value of minimal residual disease (MRD) assessment in patients with multiple myeloma treated in the MRC (Medical Research Council) Myeloma IX trial.
Multiparameter flow ...cytometry (MFC) was used to assess MRD after induction therapy (n = 378) and at day 100 after autologous stem-cell transplantation (ASCT; n = 397) in intensive-pathway patients and at the end of induction therapy in non-intensive-pathway patients (n = 245).
In intensive-pathway patients, absence of MRD at day 100 after ASCT was highly predictive of a favorable outcome (PFS, P < .001; OS, P = .0183). This outcome advantage was demonstrable in patients with favorable and adverse cytogenetics (PFS, P = .014 and P < .001, respectively) and in patients achieving immunofixation-negative complete response (CR; PFS, P = .0068). The effect of maintenance thalidomide was assessed, with the shortest PFS demonstrable in those MRD-positive patients who did not receive maintenance and longest in those who were MRD negative and did receive thalidomide (P < .001). Further analysis demonstrated that 28% of MRD-positive patients who received maintenance thalidomide became MRD negative. MRD assessment after induction therapy in the non-intensive-pathway patients did not seem to be predictive of outcome (PFS, P = .1).
MRD assessment by MFC was predictive of overall outcome in patients with myeloma undergoing ASCT. This predictive value was seen in patients achieving conventional CR as well as patients with favorable and adverse cytogenetics. The effects of maintenance strategies can also be evaluated, and our data suggest that maintenance thalidomide can eradicate MRD in some patients.
The increased number of effective therapies and the wider use of combinations that give deeper remissions have resulted in a reassessment of the goals of myeloma therapy. With the advent of new ...therapeutic strategies and diagnostic tools, achievement of minimal residual disease (MRD)-negative status has become increasingly important, with some even considering it as the primary endpoint for therapy. The level of MRD that is aimed for is a continuous, rather than an absolute variable, with studies in both transplant-eligible and -noneligible patients showing that the level of MRD achieved is predictive of progression-free survival and overall survival, with an improvement in survival of approximately 1 year for each log-depletion in MRD level. The most widely used methods to assess MRD status include flow cytometry and clonality detection, using next-generation sequencing technologies with sensitivity limits of 1:10
to 1:10
The timing of when to assess MRD depends on the treatment used, as well as the molecular and cytogenetic subgroup of the myeloma itself. It is also becoming clear that the level of MRD negativity, as well as microenvironmental factors, are important prognostically, including the regeneration of normal plasma cells, and the normalization of the immune repertoire. With advances in antibody-based therapy and immunotherapy, the achievement of stable MRD states is now possible for a significant proportion of patients, and is a prerequisite for myeloma cure.
The detection of minimal residual disease (MRD) in myeloma using a 0.01% threshold (10−4) after treatment is an independent predictor of progression-free survival (PFS), but not always of overall ...survival (OS). However, MRD level is a continuous variable, and the predictive value of the depth of tumor depletion was evaluated in 397 patients treated intensively in the Medical Research Council Myeloma IX study. There was a significant improvement in OS for each log depletion in MRD level (median OS was 1 year for ≥10%, 4 years for 1% to <10%, 5.9 years for 0.1% to <1%, 6.8 years for 0.01% to <0.1%, and more than 7.5 years for <0.01% MRD). MRD level as a continuous variable determined by flow cytometry independently predicts both PFS and OS, with approximately 1 year median OS benefit per log depletion. The trial was registered at www.isrctn.com as #68454111.
•The level of MRD quantified by flow cytometry is more informative than a 0.01% threshold and independently predicts OS.•There was approximately 1 year survival benefit per log depletion. A lower cut point for predicting improved outcome was not reached.
To elucidate the mechanisms underlying relapse from chemotherapy in multiple myeloma, we performed a longitudinal study of 33 patients entered into Total Therapy protocols investigating them using ...gene expression profiling, high-resolution copy number arrays, and whole-exome sequencing. The study illustrates the mechanistic importance of acquired mutations in known myeloma driver genes and the critical nature of biallelic inactivation events affecting tumor suppressor genes, especially TP53, the end result being resistance to apoptosis and increased proliferation rates, which drive relapse by Darwinian-type clonal evolution. The number of copy number aberration changes and biallelic inactivation of tumor suppressor genes was increased in GEP70 high risk, consistent with genomic instability being a key feature of high risk. In conclusion, the study highlights the impact of acquired genetic events, which enhance the evolutionary fitness level of myeloma-propagating cells to survive multiagent chemotherapy and to result in relapse.
•Hits in driver genes and bi-allelic events affecting tumor suppressors increase apoptosis resistance and proliferation rate–driving relapse.•Excessive biallelic inactivation of tumor suppressors in high-risk cases highlights the need for TP53-independent therapeutic approaches.
To determine the feasibility of whole-body diffusion-weighted (DW) magnetic resonance (MR) imaging for assessment of treatment response in myeloma.
This prospective single-institution study was ...HIPAA-compliant with local research ethics committee approval. Written informed consent was obtained from each subject. Eight healthy volunteers (cohort 1a) and seven myeloma patients (cohort 1b) were imaged twice to assess repeatability of quantitative apparent diffusion coefficient (ADC) estimates. Thirty-four additional myeloma patients (cohort 2) underwent whole-body DW imaging before treatment; 26 completed a posttreatment imaging. Whole-body DW data were compared before and after treatment by using qualitative (ie, observer scores) and quantitative (ie, whole-body segmentation of marrow ADC) methods. Serum paraproteins and/or light chains or bone marrow biopsy defined response.
Whole-body DW imaging scores were significantly different between observers (P < .001), but change in scores between observers after treatment was not (P = .49). Sensitivity and specificity for detecting response according to observer scores were 86% (18 of 21 patients) and 80% (4 of 5 patients) for both observers. ADC measurement was repeatable: mean coefficient of variation was 3.8% in healthy volunteers and 2.8% in myeloma patients. Pretreatment ADC in cohort 2 was significantly different from that in cohort 1a (P = .03), but not from that in cohort 1b (P = .2). Mean ADC increased in 95% (19 of 20) of responding patients and decreased in all (five of five) nonresponders (P = .002). A 3.3% increase in ADC helped identify response with 90% sensitivity and 100% specificity; an 8% increase (greater than repeatability of cohort 1b) resulted in 70% sensitivity and 100% specificity. There was a significant negative correlation between change in ADC and change in laboratory markers of response (r = -0.614; P = .001).
Preliminary work demonstrates whole-body DW imaging is a repeatable, quantifiable technique for assessment of treatment response in myeloma.
Summary Background Bisphosphonates reduce the risk of skeletal events in patients with malignant bone disease, and zoledronic acid has shown potential anticancer effects in preclinical and clinical ...studies. We aimed to establish whether bisphosphonates can affect clinical outcomes in patients with multiple myeloma. Methods Patients of age 18 years or older with newly diagnosed multiple myeloma were enrolled from 120 centres in the UK. Computer-generated randomisation sequence was used to allocate patients equally, via an automated telephone service, to receive 4 mg zoledronic acid as an infusion every 3–4 weeks or 1600 mg oral clodronic acid daily. Patients also received intensive or non-intensive induction chemotherapy. No investigators, staff, or patients were masked to treatment allocation, and bisphosphonate and maintenance therapy continued at least until disease progression. The primary endpoints were overall survival, progression-free survival, and overall response rate. We assessed between-group differences with Cox proportional hazards models for progression-free survival and overall survival, and with logistic regression models for overall response rate. Analysis was by intention to treat. This trial is registered, number ISRCTN68454111. Findings 1970 patients were enrolled between May, 2003, and November, 2007, of whom 1960 were eligible for intention-to-treat analysis: 981 in the zoledronic acid group (555 on intensive chemotherapy, 426 on non-intensive chemotherapy); and 979 on clodronic acid (556 on intensive chemotherapy, 423 on non-intensive chemotherapy). The treatment cutoff was Oct 5, 2009, with patients receiving bisphosphonates for a median of 350 days (IQR 137–632) before disease progression, with a median of 3·7 years' follow-up (IQR 2·9–4·7). Zoledronic acid reduced mortality by 16% (95% CI 4–26) versus clodronic acid (hazard ratio HR 0·84, 95% CI 0·74–0·96; p=0·0118), and extended median overall survival by 5·5 months (50·0 months, IQR 21·0 to not reached vs 44·5 months, IQR 16·5 to not reached; p=0·04). Zoledronic acid also significantly improved progression-free survival by 12% (95% CI 2–20) versus clodronic acid (HR 0·88, 95% CI 0·80–0·98; p=0·0179), and increased median progression-free survival by 2·0 months (19·5 months, IQR 9·0–38·0 vs 17·5 months, IQR 8·5–34·0; p=0·07). Rates of complete, very good partial, or partial response did not differ significantly between the zoledronic acid and clodronic acid groups for patients receiving intensive induction chemotherapy (432 patients 78% vs 422 76%; p=0·43) or non-intensive induction chemotherapy (215 50% vs 195 46%; p=0·18). Both bisphosphonates were generally well tolerated, with similar occurrence of acute renal failure and treatment-emergent serious adverse events, but zoledronic acid was associated with higher rates of confirmed osteonecrosis of the jaw (35 4%) than was clodronic acid (3 <1%). Interpretation Consistent with the potential anticancer activity of zoledronic acid, overall survival improved independently of prevention of skeletal-related events, showing that zoledronic acid has treatment benefits beyond bone health. These findings support immediate treatment with zoledronic acid in patients with newly diagnosed multiple myeloma, not only for prevention of skeletal-related events, but also for potential antimyeloma benefits. Funding Medical Research Council (London, UK), with unrestricted educational grants from Novartis, Schering Health Care, Chugai, Pharmion, Celgene, and Ortho Biotech.
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