Rajkumar, S Vincent

AbstractRisk stratification of multiple myeloma (MM) at diagnosis is critical. We examined the ability of hematopoietic indices including mean corpuscular volume (MCV), hemoglobin (Hgb), and platelet (Plt) to predict outcomes. This was a retrospective study of patients treated at Mayo Clinic between January 2004 and April 2018. We incorporated three variables (Hgb < 10 g/dL, Plt < 150 × 109/L, and MCV > 96 fL), assigning a score of 1 to each. We identified 1540 newly diagnosed MM patients, of whom 707 (46%) had a score of 0, 513 (33%) had a score of 1, 260 (17%) had a score of 2, and 60 (4%) had a score of 3. The score risk stratified patients into four groups with differing survivals. The median PFS was 32.3 months for score 0, 24.8 months for score 1, 21.7 months for score 2, and 18.3 months for score 3, for P < .001. The median OS was 80.7 months for score 0, 59.9 months for score 1, 51.7 months for score 2, and 31.3 months for score 3, P < .0001. Predictors of OS on the multivariable analysis were age ≥ 65 (HR, 1.93; P < .0001), R‐ISS stage (1‐2 vs 3) (HR, 0.48; P < .0001), and hematopoietic score (0‐2 vs 3) (HR, 0.51; P = .006). A hematopoietic score can predict survival in newly diagnosed myeloma patients.

Abstract The high-risk abnormality del(17p) can be detected by fluorescence in situ hybridization on malignant plasma cells (PCs) and has an adverse prognostic impact in patients with multiple myeloma (MM). Patients with del(17p) have reduced overall survival (OS). Patients who acquire del(17p) later during the disease course are not well described. The disease characteristics at diagnosis predicting for acquired del(17p) and its overall impact on patient survival is not known. We compared 76 patients with MM who were negative for del(17p) at diagnosis and acquired it later with 152 control MM patients who did not acquire del(17p) at a comparable time point. Patients acquired del(17p) at a median of 35.6 months (range, 4.6-116.1 months) from diagnosis of MM after a median of 2 lines of therapy (range, 1-10 lines of therapy). When compared with controls, patients with acquired del(17p) had shorter median progression-free survival (PFS) (30.1 vs 23.0 months; P = .032) and OS (106.1 vs 68.2 months; P &lt; .001) from diagnosis. After the detection of del(17p), the median PFS was 5.4 months and the median OS was 18.1 months. High lactate dehydrogenase level (odds ratio [OR], 3.69; 95% confidence interval [CI], 1.11-12.24) and presence of t(4;14) (OR, 2.66; 95% CI, 1.09-6.48) or any high-risk translocation (OR, 2.23; 95% CI, 1.00-4.95) at diagnosis predicted acquisition of del(17p). High PC proliferative rate predicted shorter OS from detection of del(17p) (hazard ratio, 2.28; 95% CI, 1.31-3.96; P = .004). Our study shows that acquisition of del(17p) is an important molecular event associated with reduction in OS in MM. Certain baseline factors may predict acquisition of del(17p). This needs validation in prospective data sets.

AbstractAchievement of a complete response has been associated with improved outcomes in patients with multiple myeloma. Recently, increasing application of minimal residual disease (MRD) assessment has shown that MRD negativity is a powerful prognostic factor for survival outcomes. We wanted to examine the impact of the polyclonal plasma cell (pPC) compartment among patients in complete response (CR) but are MRD positive. This is a retrospective cohort study where 460 myeloma patients were identified who met criteria for CR and had multicolor flow cytometry performed on the bone marrow (BM). Monoclonal and pPCs were estimated during MRD testing. Final outcomes including overall survival (OS) and time to next treatment (TTNT) were compared among the groups. The median OS for the entire cohort was not reached (95% CI; 63 mos, NR) and the median TTNT was 31 months (95% CI; 27,36). Among the MRDneg group, median TTNT was 37.6 months vs 23 months for MRDpos patients (P < .001); the median OS was not reached for either group, but there was a trend toward better survival for MRDneg patients. Among the MRDpos group, median percentage of pPCs was 65% (2.5–98.5), and those with >95% pPCs had a significantly better TTNT (NR vs 23 months; P = .02) and a trend toward better OS. We conclude that achievement of MRD negativity predicts for better response durability and trend toward improved OS and an increased proportion of pPC predicts for better outcomes within those who have residual tumor cells highlighting the importance of marrow normalization.

AbstractTrisomies of odd numbered chromosomes are seen in nearly half of patients with multiple myeloma (MM) and typically correlate with a hyperdiploid state and better overall survival (OS). We compared DNA ploidy of monoclonal plasma cells (as a surrogate for the presence of trisomies) assessed simultaneously by PCPRO (plasma cell proliferative index), a novel method that estimates DNA index by multi‐parametric flow cytometry to fluorescence in situ hybridization (FISH) in 1703 patients with plasma cell disorders. The distribution of ploidy was hyperdiploid: 759 (45%), diploid 765 (45%), hypodiploid: 71 (4%), tetraploid/near‐tetraploid: 108 (6%). FISH identified trisomies in 82% (621/756) of patients with hyperdiploidy by PCPRO and no trisomy by FISH was observed in 88% (730/834) of patients without hyperdiploidy. 95% (795/834) of patients without hyperdiploidy on PCPRO had one or less trisomy by FISH. Sensitivity and specificity of PCPRO for detecting hyperdiploidy was 86% (621/725) and 84% (730/865), respectively. Sensitivity increased to 94% (579/618) for patients with more than one trisomy. Newly diagnosed MM patients with hyperdiploidy on PCPRO (147/275) had better OS compared to nonhyperdiploid patients (median not reached vs 59 months, P = 0.008) and better progression free survival (median: 33 vs 23 months, P = 0.03). Within the hyperdiploidy group, patients with high‐hyperdiploidy (DNA index: 1.19‐1.50) versus those with low‐hyperdiploidy (DNA index: 1.05‐1.18) had superior OS (3 year OS of 88% vs 68% P = 0.03). Ploidy assessment by flow cytometry can provide rapid, valuable prognostic information and also reduces the number of copy number FISH probes required and hence the cost of FISH.

Abstract Peripheral blood biomarkers of tumor microenvironment and immune surveillance are independent prognostic factors in multiple myeloma. The timing and prognostic impact of immune reconstitution has been studied after autologous hematopoietic stem cell transplantation, less is known about its significance in newly diagnosed multiple myeloma. We studied absolute lymphocyte (ALC) and absolute monocyte (AMC) counts at the time of treatment initiation and 1 month thereafter in 771 newly diagnosed patients. Two hundred and thirty‐four patients (31%) had evidence of immune dysregulation at baseline (abnormal biomarkers). Eighty‐seven of these patients (37%) recovered normal biomarkers at 1 month (early immune reconstitution). The absence of immune dysregulation at baseline (compared to the presence thereof) was associated with better overall survival (HR 0.77, 95% CI 0.61‐0.97, P = 0.025, n = 771). The absence of immune dysregulation at 1 month (compared to the persistence or development thereof) was associated with better overall survival (HR 0.63, 95% CI 0.50‐0.80, P < 0.001, n = 771). Early immune reconstitution (compared to the persistence or development of immune dysregulation) was associated with better overall survival (HR 0.62, 95% CI 0.43‐0.92, P = 0.016, n = 771). Cytogenetic high‐risk disease was negatively, and treatment with immunomodulators positively, associated with early immune reconstitution. The presence or development of immune dysregulation in newly diagnosed multiple myeloma is an independent risk factor. The favorable impact of early immune reconstitution suggests immune dysregulation to be a potentially modifiable risk factor that may be exploited for therapeutic benefit.

AbstractPositron emission tomography‐computed tomography (PET‐CT) can identify bony lesions, assess disease burden, and detect extramedullary disease (EMD) in patients with multiple myeloma. We retrospectively reviewed records of patients who underwent PET‐CT within 60 days of a new diagnosis (before therapy commenced) to identify the nature and prognostic impact of PET‐CT abnormalities. Patients (N = 313) were seen from April 2005 through June 2017. Of the 234 patients (75%) with focal lesions (FLs), 182 (58%) had at least 3 FLs, 38 (12%) had EMD, and 204 (65%) had documented myelomatous lytic lesions. The median maximum standardized uptake value (SUVmax) for the entire cohort was 5.9 (range 1.5‐48.3). Presence of at least 3 FLs and EMD predicted inferior overall survival (OS); median OS was 57.8 months for patients with 3 or more FLs and 103.6 months for patients with fewer than 3 FLs (P = .003). The median OS was 45.5 and 71.8 months for patients with and without EMD, respectively (P = .004). No clear SUVmax cutoff was predictive of progression‐free survival or OS. PET‐CT is a valuable tool for assessing disease burden and could provide prognostic information about a contemporary cohort of patients with newly diagnosed myeloma who received treatment with novel agents.

AbstractSymptomatic hyperviscosity is a well‐established phenomenon in Waldenström macroglobulinemia (WM). Monoclonal IgM can variably impact intrinsic serum viscosity, leading to widely disparate symptomatic thresholds for development of hyperviscosity‐related symptoms. Data regarding the predictors of symptomatic hyperviscosity and outcomes related to this complication remain scarce and a recent study proposed that IgM >6000 mg/dL be considered a new criterion for initiating therapy in otherwise asymptomatic (smoldering) WM to pre‐empt hyperviscosity‐related injury. Herein, we attempt to identify predictors of the development of symptomatic hyperviscosity and its impact in patients with WM. Of 997 WM patients evaluated from January, 1996 through June, 2017, symptomatic hyperviscosity was observed in 130 (13%) patients. Overall survival (OS) of these 130 patients was similar to that of patients without symptomatic hyperviscosity (median: 11.5 vs 11.6 years; P = 0.63). On multivariate‐analysis, only viscosity >1.8 cp (risk ratio: 4.0, P = 0.02) assessed at the time of WM diagnosis was an independent predictor for the development of subsequent symptomatic hyperviscosity. Among patients with smoldering WM and IgM >6000 mg/dL at diagnosis (n = 13) who were managed expectantly, the median time‐to‐initial therapy was 6.9 years and only 15% developed hyperviscosity‐related symptoms subsequently. In summary, the occurrence of symptomatic hyperviscosity does not impact OS. Serum viscosity at diagnosis of WM, and not IgM concentration, represents the single most important independent predictor for development of subsequent hyperviscosity‐related symptoms. Patients with smoldering WM and high serum IgM can be safely observed in the absence of any indications per the Consensus recommendations to initiate WM‐directed therapy.