Kyle, Robert A.

AbstractResponse rates in newly diagnosed multiple myeloma have improved dramatically with the introduction of highly effective novel therapies. However, survival in patients achieving optimal responses to initial treatment can vary significantly, and new prognostic indicators are required to improve risk stratification. We investigated the relationship between time to plateau (TPlat) and survival in 1099 newly diagnosed patients treated with novel agents at our institution from 2005 to 2015.TPlatwas defined as time from initiation of first‐line therapy to best response to first‐line therapy. The medianTPlatwas 4.9 months (0.7‐58.6) and plateau duration was 1.8 years (0.2‐11.0). Patients who required > 120 days to achieve a plateau had longer modified overall survival (mOS) and progression free survival (mPFS) calculated from a landmark of best response (P < .001 for both comparisons). Statistically significant improvement in mOS was retained in subgroup analysis based on age and whether patients received upfront autologous hematopoietic stem cell transplantation (ASCT) (P < .001 for all comparisons). Our results suggest that patients who respond more gradually to initial therapy (TPlat > 120 days) experience longer survival compared to more rapid responders. Patients with a prolongedTPlatcould represent an “ongoing responder” phenotype that portends a survival advantage independent of treatment with upfront ASCT, depth of response, and biologic markers such as ISS stage and cytogenetic risk.

Purpose To update guideline recommendations on the role of bone-modifying agents in multiple myeloma. Methods An update panel conducted a targeted systematic literature review by searching PubMed and the Cochrane Library for randomized controlled trials, systematic reviews, meta-analyses, clinical practice guidelines, and observational studies. Results Thirty-five relevant studies were identified, and updated evidence supports the current recommendations. Recommendations For patients with active symptomatic multiple myeloma that requires systemic therapy with or without evidence of lytic destruction of bone or compression fracture of the spine from osteopenia on plain radiograph(s) or other imaging studies, intravenous administration of pamidronate 90 mg over at least 2 hours or zoledronic acid 4 mg over at least 15 minutes every 3 to 4 weeks is recommended. Denosumab has shown to be noninferior to zoledronic acid for the prevention of skeletal-related events and provides an alternative. Fewer adverse events related to renal toxicity have been noted with denosumab compared with zoledronic acid and may be preferred in this setting. The update panel recommends that clinicians consider reducing the initial pamidronate dose in patients with preexisting renal impairment. Zoledronic acid has not been studied in patients with severe renal impairment and is not recommended in this setting. The update panel suggests that bone-modifying treatment continue for up to 2 years. Less frequent dosing has been evaluated and should be considered in patients with responsive or stable disease. Continuous use is at the discretion of the treating physician and the risk of ongoing skeletal morbidity. Retreatment should be initiated at the time of disease relapse. The update panel discusses measures regarding osteonecrosis of the jaw. Additional information is available at www.asco.org/hematologic-malignancies-guidelines and www.asco.org/guidelineswiki .

AbstractWaldenström macroglobulinemia (WM) is an immunoglobulin M‐associated lymphoma, with majority of cases demonstrating MYD88 locus alteration, most commonly, MYD88L265P. Owing to low prevalence of the wild‐type (WT) MYD88 genotype in WM, clinically relevant data in this patient population are sparse, with one study showing nearly a 10‐fold increased risk of mortality in this subgroup compared to patients with MYD88L265P mutation. We studied a large cohort of patients with MYD88L265P and MYD88WT WM, evaluated at Mayo Clinic, Rochester, between 1995 and 2016, to specifically assess the impact of these genotypes on clinical course. Of 557 patients, MYD88L265P mutation status, as determined by allele‐specific polymerase chain reaction, was known in 219, and 174 (79%) of those exhibited MYD88L265P, 157 of 174 patients had active disease. Of 45 (21%) patients with MYD88WT genotype, 44 had active disease. The estimated median follow‐up was 7.0 years; median overall survival was 10.2 years (95% CI: 8.4‐16.5) for MYD88L265P versus 13.9 years (95% CI: 6.4‐29.3) for the MYD88WT (P = 0.86). The time‐to‐next therapy from frontline treatment and the presenting features were similar in the two patient populations. For patients with smoldering WM at diagnosis, the median time‐to‐progression to active disease was 2.8 years (95% CI: 2.2‐3.8) in the MYD88L265P cohort and 1.9 years (95% CI: 0.7‐3.1) in the MYD88WT cohort (P = 0.21). The frequency of transformation to high‐grade lymphoma, or the development of therapy‐elated myelodysplastic syndrome was higher in the MYD88WT cohort (16% versus 4% in the MYD88L265P, P = 0.009). In conclusion, MYD88L265P mutation does not appear to be a determinant of outcome, and its presence may not be a disease‐defining feature in WM. Our findings warrant external validation, preferably through prospective studies.

AbstractExperience with intensive chemotherapy for relapsed/refractory multiple myeloma (RRMM) using VDT PACE regimen and its modifications (VDT PACE‐like regimens: VPLRs) outside TOTAL THERAPY trials is limited. We analyzed the outcomes of 141 patients with RRMM who received VPLRs at our center between 2006 and 2017 in an intent‐to‐treat analysis. Median age was 59.7 years and 66.7% of patients were male. A median of 2.2 years (range 0.02‐11.4) separated diagnosis of myeloma and inititation of VPLR. High‐risk cytogenetics were present in 52.4% patients. Patients received a median of 4 (range 1‐14) prior therapies, including stem cell transplant (SCT) in 66.7% patients. Ninety‐five (67.4%) patients received VDT PACE, 20 (14.2%) patients received VD PACE and 26 (18.4%) patients received other VPLRs. Patients received a median of 1 cycle (range 1‐9) of VPLR. We observed ≥ minimal response in 68.4%, ≥ partial response (PR) in 54.4% and ≥ very good PR in 10.3% patients. Median progression‐free survival was 3.1 months (95% CI, 1.9‐3.9) and median overall survival (OS) was 8.1 months (CI, 6.2‐9.9). One‐hundred and sixteen (82.3%) patients received some therapy after VPLR; 71 (61.2%) received systemic chemotherapy, while 45 (38.8%) underwent SCT. Median OS for those who received SCT after VPLR was 15.1 months (CI, 10.3‐20.8). Age ≥ 60 years (hazard ratio [HR] 2.3 [CI, 1.4‐3.7]; P = 0.0008) and R‐ISS III stage (HR‐ 2.4 [CI, 1.3‐4.0]; P = 0.003) predicted shorter OS in patients receiving VPLR. VPLRs are effective in heavily pre‐treated RRMM. In fit patients, SCT can be used to consolidate the response to VPLR.