Characteristics and risk factors for thrombosis in POEMS syndrome: A retrospective evaluation of 230 patients.

Thromboses are prevalent in POEMS syndrome, but few risk factors for POEMS-associated thrombosis have been identified. The objective of this study is to identify novel risk factors for POEMS-associated thrombosis. In this retrospective cohort of 230 POEMS patients, 27% developed thrombosis. Arterial events were slightly more common than venous. Stroke accounted for 26% of all thromboses and 53% of arterial events. There were differences in baseline features between the thrombosis group and the no thrombosis group, and these were driven by patients with arterial thrombosis. Risk factors for arterial thrombosis included thrombocytosis, elevated hemoglobin/hematocrit, extravascular volume overload, and splenomegaly. Hyperprolactinemia appeared to be a risk factor for venous thrombosis. The risk of thrombosis was most striking among men with elevated hemoglobin (32% vs. 5%, p < .001) and hematocrit (42% vs. 5%, p < .001) compared to men without. Most thromboses occurred prior to POEMS directed therapy, and most that occurred during therapy happened within 3 months of diagnosis. Twenty-one percent of patients with thrombosis had recurrence. In recognition of high overall rates of thrombosis in this population, all patients with POEMS syndrome should receive prophylactic antiplatelet therapy, and clinicians should consider anticoagulation in patients with risk factors for POEMS-associated thrombosis.

Time to plateau as a predictor of survival in newly diagnosed multiple myeloma.

Response 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. TPlat was defined as time from initiation of first-line therapy to best response to first-line therapy. The median TPlat was 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 prolonged TPlat could 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.

MASS-FIX for the detection of monoclonal proteins and light chain N-glycosylation in routine clinical practice: a cross-sectional study of 6315 patients.

Immunoenrichment-based matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), termed MASS-FIX, offers several advantages over immunofixation for the detection and isotyping of serum monoclonal protein, including superior sensitivity and specificity, the ability to differentiate therapeutic monoclonal antibodies, and the rapid identification of light chain (LC) N-glycosylation. We identified 6315 patients with MASS-FIX performed at our institution since 2018. Of these, 4118 patients (65%) with a wide array of plasma cell disorders (PCD), including rare monoclonal gammopathies of clinical significance, had a positive MASS-FIX. Two-hundred twenty-one (5%) of the MASS-FIX positive patients had evidence of LC N-glycosylation, which was more commonly identified in IgM heavy chain isotype, kappa LC isotype, and in diagnoses of immunoglobulin light chain (AL) amyloidosis and cold agglutinin disease (CAD) compared to other PCD. This cross-sectional study describes the largest cohort of patients to undergo MASS-FIX in routine clinical practice. Our findings demonstrate the widespread utility of this assay, and confirm that LC N-glycosylation should prompt suspicion for AL amyloidosis and CAD in the appropriate clinical context.

Metaphase cytogenetics and plasma cell proliferation index for risk stratification in newly diagnosed multiple myeloma.

Metaphase cytogenetic abnormalities, plasma cell proliferation index (PCPro), and gain 1q by fluorescence in situ hybridization (FISH) are associated with inferior survival in newly diagnosed multiple myeloma (MM) treated with novel agents; however, their role in risk stratification is unclear in the era of the revised International Staging System (R-ISS). The objective of this study was to determine if these predictors improve risk stratification in newly diagnosed MM when accounting for R-ISS and age. We studied a retrospective cohort of 483 patients with newly diagnosed MM treated with proteasome inhibitors and/or immunomodulators. On multivariable analysis, R-ISS, age, metaphase cytogenetic abnormalities (both in aggregate and for specific abnormalities), PCPro, and FISH gain 1q were associated with inferior progression-free (PFS) and overall survival (OS). We devised a risk scoring system based on hazard ratios from multivariable analyses and assigned patients to low-, intermediate-, and high-risk groups based on their cumulative scores. The addition of metaphase cytogenetic abnormalities, PCPro, and FISH gain 1q to a risk scoring system accounting for R-ISS and age did not improve risk discrimination of Kaplan-Meier estimates for PFS or OS. Moreover, they did not improve prognostic performance when evaluated by Uno's censoring-adjusted C-statistic. Lastly, we performed a paired analysis of metaphase cytogenetic and interphase FISH abnormalities, which revealed the former to be insensitive for the detection of prognostic chromosomal abnormalities. Ultimately, metaphase cytogenetics lack sensitivity for important chromosomal aberrations and, along with PCPro and FISH gain 1q, do not improve risk stratification in MM when accounting for R-ISS and age.

Development of thrombocytopenia during first-line treatment and survival outcomes in newly diagnosed multiple myeloma.

The prognostic significance of novel agent-induced thrombocytopenia in newly diagnosed multiple myeloma (MM) is unknown. We identified 665 newly diagnosed patients receiving proteasome inhibitors and/or immunomodulators with pretreatment platelet counts ≥100,000/µL. Median progression-free survival (PFS) was 1.88 years (95% CI 1.48-2.38) for patients who developed treatment-related thrombocytopenia (<100,000/µL) within sixty days of initiation of first-line therapy, compared to 2.64 years (95% CI 2.39-2.78) in patients who did not (p = .042), while median overall survival (OS) was 5.70 years (95% CI 3.02-9.00) and 8.43 years (95% CI 6.62-9.17), respectively (p = .030). Platelet count reduction >70% from pretreatment baseline was similarly predictive of inferior PFS and OS. This is the first study to demonstrate the predictive and prognostic value of treatment-related thrombocytopenia in newly diagnosed MM.