Timing of high-dose methotrexate CNS prophylaxis in DLBCL: a multicenter international analysis of 1384 patients.

Prophylactic high-dose methotrexate (HD-MTX) is often used for diffuse large B-cell lymphoma (DLBCL) patients at high risk of central nervous system (CNS) relapse, despite limited evidence demonstrating efficacy or the optimal delivery method. We conducted a retrospective, international analysis of 1384 patients receiving HD-MTX CNS prophylaxis either intercalated (i-HD-MTX) (n = 749) or at the end (n = 635) of R-CHOP/R-CHOP-like therapy (EOT). There were 78 CNS relapses (3-year rate 5.7%), with no difference between i-HD-MTX and EOT: 5.7% vs 5.8%, P = .98; 3-year difference: 0.04% (-2.0% to 3.1%). Conclusions were unchanged on adjusting for baseline prognostic factors or on 6-month landmark analysis (n = 1253). In patients with a high CNS international prognostic index (n = 600), the 3-year CNS relapse rate was 9.1%, with no difference between i-HD-MTX and EOT. On multivariable analysis, increasing age and renal/adrenal involvement were the only independent risk factors for CNS relapse. Concurrent intrathecal prophylaxis was not associated with a reduction in CNS relapse. R-CHOP delays of ≥7 days were significantly increased with i-HD-MTX vs EOT, with 308 of 1573 (19.6%) i-HD-MTX treatments resulting in a delay to subsequent R-CHOP (median 8 days). Increased risk of delay occurred in older patients when delivery was later than day 10 in the R-CHOP cycle. In summary, we found no evidence that EOT delivery increases CNS relapse risk vs i-HD-MTX. Findings in high-risk subgroups were unchanged. Rates of CNS relapse in this HD-MTX-treated cohort were similar to comparable cohorts receiving infrequent CNS prophylaxis. If HD-MTX is still considered for certain high-risk patients, delivery could be deferred until R-CHOP completion.

BH3 profiling identifies ruxolitinib as a promising partner for venetoclax to treat T-cell prolymphocytic leukemia.

Conventional therapies for patients with T-cell prolymphocytic leukemia (T-PLL), such as cytotoxic chemotherapy and alemtuzumab, have limited efficacy and considerable toxicity. Several novel agent classes have demonstrated preclinical activity in T-PLL, including inhibitors of the JAK/STAT and T-cell receptor pathways, as well as histone deacetylase (HDAC) inhibitors. Recently, the BCL-2 inhibitor venetoclax also showed some clinical activity in T-PLL. We sought to characterize functional apoptotic dependencies in T-PLL to identify a novel combination therapy in this disease. Twenty-four samples from patients with primary T-PLL were studied by using BH3 profiling, a functional assay to assess the propensity of a cell to undergo apoptosis (priming) and the relative dependence of a cell on different antiapoptotic proteins. Primary T-PLL cells had a relatively low level of priming for apoptosis and predominantly depended on BCL-2 and MCL-1 proteins for survival. Selective pharmacologic inhibition of BCL-2 or MCL-1 induced cell death in primary T-PLL cells. Targeting the JAK/STAT pathway with the JAK1/2 inhibitor ruxolitinib or HDAC with belinostat both independently increased dependence on BCL-2 but not MCL-1, thereby sensitizing T-PLL cells to venetoclax. Based on these results, we treated 2 patients with refractory T-PLL with a combination of venetoclax and ruxolitinib. We observed a deep response in JAK3-mutated T-PLL and a stabilization of the nonmutated disease. Our functional, precision-medicine-based approach identified inhibitors of HDAC and the JAK/STAT pathway as promising combination partners for venetoclax, warranting a clinical exploration of such combinations in T-PLL.

Work and education interruption in long-term Hodgkin lymphoma survivors: an analysis among patients from nine EORTC-LYSA trials.

BACKGROUND: Disease-specific studies on the impact of Hodgkin lymphoma (HL) on education or work interruption and resumption are lacking. MATERIAL AND METHODS: In a cross-sectional study conducted among long-term HL survivors enrolled from 1964 to 2004 in nine randomised EORTC-LYSA trials, the interruption and resumption of education/work was investigated. Survivors alive 5-44 years after diagnosis who were studying or working at time of diagnosis were included (n = 1646). Patient and treatment characteristics were obtained from trial records. Education and work outcomes were collected using the Life Situation Questionnaire. Logistic regression was used to model education or work interruption; Cox regression was used to study resumption rates. RESULTS: Among survivors studying at time of diagnosis (n = 323), 52% (95% CI: 46-57%) interrupted their education; however, it was resumed within 24 months by 92% (95% CI: 87-96%). The probability of interruption decreased with time: the more recent the treatment era, the lower the risk (OR 0.70 per 10 years, 95% CI: 0.49-1.01). Treatment with radiotherapy (yes vs. no) was associated with a higher education resumption rate (HR 2.01, 95% CI 1.07-3.78) whereas age, sex, stage, radiotherapy field and chemotherapy were not.Among survivors working at time of diagnosis (n = 1323), 77% (95% CI: 75-79%) interrupted their work. However, it was resumed within 24 months by 86% (95% CI: 84%-88%). Women were more likely to interrupt their work as compared to men (OR 1.90, 95% CI: 1.44-2.51) and, when interrupted, less likely to resume work (HR 0.70, 95% CI: 0.61-0.80). Survivors with a higher educational level were less likely to interrupt their work (OR 0.68 for university vs. no high school, 95% CI: 0.46-1.03); and when interrupted, more likely to resume work (HR 1.50 for university vs. no high school, 95% CI: 1.21-1.86). Increasing age was also associated with lower resumption rates (HR 0.62 for age ≥50 vs. 18-29 years, 95% CI: 0.41-0.94). CONCLUSION: An interruption in education/work was common among long-term HL survivors. However, most of the survivors who interrupted their studies or work had resumed their activities within 24 months. In this study, no associations between survivors' characteristics and failure to resume education were observed. Female sex, age ≥50 years, and a lower level of education were found to be associated with not resuming work after treatment for HL.

Outcomes after allogeneic hematopoietic stem cell transplantation for adults with primary mediastinal B cell lymphoma: a SFGM-TC and LYSA study.

Background: Despite therapeutic progress, 10 to 30% of adult patients with primary mediastinal B cell lymphoma (PMBCL) are primary refractory or experience early relapse (R/R). Allogeneic stem cell transplantation (allo-HSCT) thus remains a potentially curative option in this setting.Material and Methods: In this multicenter retrospective study, the outcomes of 33 French and Belgian adult patients allo-transplanted for R/R PMBCL between January 1999 and December 2018, were examined.Results: At allo-HSCT time, patients had received a median of 3 treatment lines, 50% of them were in complete response, 40% in partial response and 10% had a progressive disease. Forty-two percent of the donors were siblings and 39% matched related. The median follow-up for alive patients was 78 months (3.5-157). Considering the whole cohort, 2-year overall survival (OS), progression free survival (PFS) and graft-versus-host disease-free/relapse-free survival (GRFS) were 48% (95%CI: 33-70), 47% (95%CI: 33-68) and 38.5% (95%CI: 25-60) respectively. Cumulative incidence of relapse and non-relapse mortality rates were respectively 34% (95%CI: 18-50) and 18% (95%CI: 7-34). Disease status at transplant was the only factor predicting survivals, patients with progressive disease showing significant lower 2-year PFS (HR: 6.12, 95%CI: 1.32-28.31, p = 0.02) and OS (HR: 7.04, 95%CI: 1.52-32.75, p = 0.013). A plateau was observed for OS and PFS after 4 years with 10 patients alive after this date, suggesting that almost one third of the patients effectively salvaged and undergoing allo-SCT could be cured.Conclusion: This study indicates that allo-HSCT is a valid therapeutic option for R/R PMBCL, providing durable remissions.

Management of Hodgkin Lymphoma during pregnancy, review of the literature and description of an homogenous expectative attitude associated with excellent outcome.

Hodgkin lymphoma (HL) occuring during pregnancy is a rare condition, and management relies on sparse literature. The specificity of pregnancy requires the clinician to take into account the clinical emergency, the stage of the lymphoma, the trimester of pregnancy, and the patient's choices. The main objective is twofold: to limit the risk of toxicity and adverse events for both mother and fetus, without reducing the chances of a successful outcome. Current literature data suggest that the use of ABVD-type polychemotherapy (adriamycin, bleomycin, vinblastine, dacarbazine) is associated with obstetrical events and long-term fetal toxicity. We report here the results of a homogeneous management considering wait-and-see, vinblastine monotherapy and ABVD polychemotherapy options. The outcomes in terms of obstetrical complications, response rate, and overall survival (100 %) reinforce the idea that strategies that do not involve the use of multidrug therapy are possible and are associated with very good results.

Identification, risk factors, and clinical course of CNS relapse in DLBCL patients across 19 prospective phase 2 and 3 trials-a LYSA and GLA/ DSHNHL collaboration.

Progression or relapse in the central nervous system (CNS) remains a rare but mostly fatal event for patients with diffuse large B-cell lymphoma (DLBCL). In a retrospective analysis of 5189 patients treated within 19 prospective German and French phase 2/3 trials, we identified 159 patients experiencing a CNS event (relapse: 62%, progression: 38%). Intracerebral, meningeal, intraspinal, or combined involvement was reported in 44%, 31%, 3%, and 22% of patients, respectively. 62 of 155 evaluable patients (40%) showed concurrent systemic progression/ relapse. 82% of all CNS events occurred within two years after study inclusion or randomization. 87% of patients showed extranodal involvement outside the CNS. Patients generally had poor outcomes with a median overall survival (OS) of 3.4 months (95% CI 2.9-4.2) and a 2-year OS of 15% (10-22%). Outcomes did not differ depending on the site or time point of CNS events. Patients with isolated CNS events demonstrated significantly better OS (p = 0.023). Twenty-five patients were consolidated with autologous or allogeneic stem cell transplantation and achieved a 3-year OS of 36% (20-66%). This large study including more than 5000 DLBCL patients highlights the unmet medical need to improve the outcome of DLBCL patients suffering from CNS relapse.

Identification of primary mediastinal B-cell lymphomas with higher clonal dominance and poorer outcome using 5' RACE.

Few data exist regarding the tumor B-cell receptor (BCR) repertoire and lymphoid microenvironment in primary mediastinal B-cell lymphoma (PMBL). We applied 5' rapid amplification of cDNA ends (5'RACE) to tumor RNA samples from 137 PMBL patients with available gene expression profiling and next-generation sequencing data. We obtained 5'RACE results for 75/137 (54.7%) patients, with clinical characteristics as follows: median [min-max] age, 33 [18-64] years; female, 53.3%; ECOG score 0-1, 86.7%; stage I-II, 57.3%; 1st-line treatment with anti-CD20 plus ACVBP, 72%; CHOP14, 14.7%; CHOP21, 13.3%. Among the 60 biopsies that expressed a productive BCR, we highlighted a strong somatic hypermutation profile with 58 (96.7%) patients carrying mutated IgVH, defined as <98% identity to the germline sequence. We then identified a subgroup of 12/75 patients (16%) with a worse prognosis (progression-free survival (PFS): HR [95% CI]=17 [3.2-88]; overall survival (OS): HR=21 [2.1-210]) associated with the highest clonal dominance status (HCD), defined by the dominant clonotype representing >81.1% and >78.6% of all CDR3 sequences for IgVH and IgVL, respectively. Compared to other patients, this subgroup had similar clinical characteristics but a greater median allele frequency for all somatic variants, decreased BCR diversity, and greater expression of PDL1/PDL2 and MS4A1 genes, suggesting a greater tumoral infiltration. According to a multivariate model integrating AID expression and BCR diversity, only HCD status was associated with outcome (PFS: HR=14.6 [2.46-86.8]; OS: HR=11.4 [1-128.8]). We confirmed this poorer prognosis in an independent cohort, in which 6/37 (16%) patients exhibited HCD (PFS: HR=12 [3-46]; OS: HR=17 [1.8-170]).

Central nervous system relapse in younger patients with diffuse large B-cell lymphoma: a LYSA and GLA/DSHNHL analysis.

Most patients with diffuse large B-cell lymphoma (DLBCL) can be cured with immunochemotherapy such as R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone). Patients with progression or relapse in the central nervous system (CNS) face dismal outcomes. The impact of more aggressive regimens used in frontline therapy has not been systematically investigated in this context. To this end, we analyzed a large cohort of 2203 younger patients with DLBCL treated on 10 German (German Lymphoma Alliance [GLA]/The German High Grade Non-Hodgkin's Lymphoma Study Group [DSHNHL]) and French (The Lymphoma Study Association [LYSA]) prospective phase 2 and 3 trials after first-line therapy with R-CHOP, R-CHOEP (R-CHOP + etoposide), dose-escalated R-CHOEP followed by repetitive stem cell transplantation (R-MegaCHOEP), or R-ACVBP (rituximab, doxorubicin, cyclophosphamide, vindesine, bleomycine, and prednisone) followed by consolidation including multiple drugs crossing the blood-brain barrier (BBB). Patients with DLBCL with an age-adjusted International Prognostic Index (aaIPI) of 0 to 1 showed very low cumulative incidence rates of CNS relapse regardless of first-line therapy and CNS prophylaxis (3-year cumulative incidences 0%-1%). Younger high-risk patients with aaIPI of 2 to 3 had 3-year cumulative incidence rates of 1.6% and 4% after R-ACVBP plus consolidation or R-(Mega)CHO(E)P, respectively (hazard ratio 2.4; 95% confidence interval: 0.8-7.4; P = .118). Thus, for younger high-risk patients, frontline regimens incorporating agents crossing the BBB may reduce often fatal CNS relapse.

Efficacy and safety of crizotinib in ALK-positive systemic anaplastic large-cell lymphoma in children, adolescents, and adult patients: results of the French AcSé-crizotinib trial.

BACKGROUND: The French phase II AcSé-crizotinib trial aimed to evaluate the safety and efficacy of crizotinib in patients with ALK, ROS1, and MET-driven malignancies, including ALK-positive anaplastic large-cell lymphoma (ALK+ ALCL). METHODS: ALK+ ALCL patients 12 months or older with measurable disease and no standard care options available received crizotinib twice daily at 165 mg/m2 in children and adolescents and 250 mg in adults. The primary end-point was the response rate at 8 weeks. RESULTS: Twenty-eight patients were enroled between February 2014 and March 2018. Three patients who were not treated were excluded from the analysis. The median age was 19 years. The median previous line of chemotherapy was two. In the 24 patients with an evaluable response, the response rate at 8 weeks was 67% (95% CI: 47-82%). All patients discontinued crizotinib after a median treatment duration of 3.7 months: eight for progression, two for adverse events (AEs) related to prior treatments, and 15 by choice, including six for allogeneic stem-cell transplantation. The median follow-up was 45 months. Nine patients experienced an event: eight relapses (seven after crizotinib discontinuation and one after dose reduction), and one died in complete remission. The median duration of response was 43.3 months (95% CI: 8.3-not reached). The 3-year progression-free and overall survival rates were 40% (95% CI: 23-59%) and 63% (95% CI: 43-79%). Grade 3 or 4 treatment-related AEs occurred in 32% of patients. CONCLUSION: Crizotinib shows efficacy and an acceptable safety profile in ALK+ ALCL relapsed/refractory patients. However, a large proportion of patients experience a relapse after crizotinib discontinuation. Future studies will assess if prolonged ALK inhibitor exposure has curative potential without consolidation.

Employment situation among long-term Hodgkin lymphoma survivors in Europe: an analysis of patients from nine consecutive EORTC-LYSA trials.

PURPOSE: Little is known about the employment situation of long-term Hodgkin lymphoma (HL) survivors despite their young age at diagnosis and the favorable prognosis of the disease. In this cross-sectional study, we aim to describe the employment situation in a cohort of long-term HL survivors compared to the general population and investigate the associations with disease characteristics and treatment exposure. METHODS: HL survivors > 25 years (n = 1961) were matched 1:25 to controls (n = 49,025) from the European Union Labour Force Survey. Individual treatment information was obtained from trial records. Employment and socio-demographic characteristics were collected using the Life Situation Questionnaire. Logistic regression models were used to estimate associations between disease and treatment characteristics with employment status and work-related attitudes. RESULTS: At employment assessment, 69.7% of survivors (95% CI: 67.6-71.7%) were working; of these, 68.9% (95% CI: 66.3-71.3%) worked full-time, a figure comparable to that of controls (p value 0.17). The risk of not working was associated with increasing age at diagnosis, increasing age at survey, female sex, lower educational level, and relapse history. Of those who were at work during treatment, 16.8% (95% CI: 14.5-19.3%) stated their income had subsequently decreased, which was attributed to their HL by 65.4% (95% CI: 57.5-72.8). Among those not at work, 25.1% (95% CI: 20.7-29.8) survivors were disabled compared to only 14.5% (95% CI: 13.8-15.3%) of controls. CONCLUSIONS: In this cohort of HL survivors, employment status was comparable to that of the general population. However, increasing age at follow-up, female sex, lower educational level, and relapse history are risk factors for unemployment, a perceived decrease in income, and disability. IMPLICATIONS FOR CANCER SURVIVORS: To further improve follow-up care, special attention should be paid to these vulnerable subgroups.

Discovery of Candidate DNA Methylation Cancer Driver Genes.

Epigenetic alterations, such as promoter hypermethylation, may drive cancer through tumor suppressor gene inactivation. However, we have limited ability to differentiate driver DNA methylation (DNAme) changes from passenger events. We developed DNAme driver inference-MethSig-accounting for the varying stochastic hypermethylation rate across the genome and between samples. We applied MethSig to bisulfite sequencing data of chronic lymphocytic leukemia (CLL), multiple myeloma, ductal carcinoma in situ, glioblastoma, and to methylation array data across 18 tumor types in TCGA. MethSig resulted in well-calibrated quantile-quantile plots and reproducible inference of likely DNAme drivers with increased sensitivity/specificity compared with benchmarked methods. CRISPR/Cas9 knockout of selected candidate CLL DNAme drivers provided a fitness advantage with and without therapeutic intervention. Notably, DNAme driver risk score was closely associated with adverse outcome in independent CLL cohorts. Collectively, MethSig represents a novel inference framework for DNAme driver discovery to chart the role of aberrant DNAme in cancer. SIGNIFICANCE: MethSig provides a novel statistical framework for the analysis of DNA methylation changes in cancer, to specifically identify candidate DNA methylation driver genes of cancer progression and relapse, empowering the discovery of epigenetic mechanisms that enhance cancer cell fitness.This article is highlighted in the In This Issue feature, p. 2113.

Renal Pathologic Findings in TAFRO Syndrome: Is There a Continuum Between Thrombotic Microangiopathy and Membranoproliferative Glomerulonephritis? A Case Report and Literature Review.

Background: TAFRO syndrome is a clinical subtype of idiopathic multicentric Castleman disease (iMCD) that is characterized by thrombocytopenia, anasarca, fever and/or elevated serum C-reactive protein, renal dysfunction, and organomegaly. Case Presentation: A 28-year-old woman with fever, weight gain of 13 kgs, lower extremity edema, hepatosplenomegaly, and multicentric peripheral lymphadenopathy was referred to our center. Laboratory investigations revealed anemia, thrombocytopenia, creatinine at 1.19 mg/dL and hypoalbuminemia at 33 g/L. Proteinuria was measured at 2 g/day including albuminuria at 1.5 g/day. Urinary sediment examination found leukocyturia at 44,000/mL and hematuria at 645,000/mL. Vascular endothelial growth factor (VEGF) level was elevated. A cervical lymph node biopsy found features consistent with the mixed histopathological subtype of iMCD. A renal biopsy revealed a membranoproliferative glomerulonephritis (MPGN) pattern. We initiated 3 days of methylprednisolone pulse-therapy at 1,000 mg per day, followed by prednisone 1 mg/kg/day and evolution was favorable. Review of Literature: 19 iMCD patients with TAFRO syndrome had undergone a renal biopsy: 8 cases with author's diagnosis consistent with MPGN-like and 11 cases of thrombotic microangiopathy (TMA)-like glomerulopathy without fibrin thrombi in glomerular capillaries or arterioles and without typical biological signs. Clinical, biological, and outcome characteristics were similar between the cases described as having MPGN and TMA-like presentation. After a thorough review of histopathological descriptions for each case, MPGN lesions seems to be the consequences of chronic glomerular endothelial injury in persistent TMA. We suspect that VEGF and IL-6 play a key role in the physiopathology of the spectrum of renal involvement from TMA-like to MPGN observed in TAFRO syndrome. Conclusion: We present a Caucasian iMCD patient with TAFRO syndrome with renal insufficiency secondary to MPGN, which might be secondary to a chronic TMA-like disease. We suspect that there is a continuum between TMA and MPGN lesions in TAFRO syndrome favored by VEGF and IL-6.

Discontinuation of antimicrobial therapy in adult neutropenic haematology patients: A prospective cohort.

OBJECTIVES: Antibiotics for febrile neutropenia (FN) in acute myeloid leukaemia (AML) patients undergoing intensive chemotherapy are usually maintained until neutropenia resolution, because of the risk of uncontrolled sepsis in this vulnerable population. This leads to unnecessarily prolonged antimicrobial therapy. METHODS: Based on ECIL-4 recommendations, we modified our management strategy and discontinued antibiotics after a pre-established duration in patients treated for a first episode of FN between August 2014 and October 2017. RESULTS: Antibiotics were stopped during 62 FN episodes, and maintained in the control group (n = 13). Median age of patients was 54 years. A total of 39 (63%) patients received induction and 23 (37%) consolidation chemotherapy; 36 (58%) patients had fever of unknown origin. Median neutropenia length was 26 days (IQR 24-30). Antibiotics were started at day 9 (IQR 5-13). Most patients received piperacillin-tazobactam (56%) or cefepime (32%). Antimicrobial therapy was longer in the control group than in the policy compliant group, 10 (IQR 7-16) vs. 19 days (IQR 15-23), P = 0.0001. After antibiotics discontinuation, 20% patients experienced fever recurrence, within 5.5 days (IQR 3-7.5). None of these febrile episodes were severe and 80% patients remained afebrile, with neutrophil recovery occurring within 5 days (IQR 2-8.5). Overall, 287 antibiotics days were spared; this represents 49% of all days with antibiotics. No patient had died at day 30 from intervention; six died during late follow-up, two from graft-versus-host disease and four from relapsed or refractory leukaemia. CONCLUSIONS: Discontinuing antibiotics in neutropenic AML patients treated for a first episode of FN is safe, and results in significant antibiotic sparing.

Response to pneumococcal vaccination in multiple myeloma.

BACKGROUND: Streptococcus pneumoniae infection causes morbidity and mortality in multiple myeloma patients. Pneumococcal vaccination is commonly given to immunocompromised myeloma patients; however response data are sparse. Here, we present longitudinal response data to pneumococcal vaccination in multiple myeloma patients. METHOD: Twenty-eight multiple myeloma patients were included, 25 of whom were newly diagnosed. All the patients received two vaccines Prevnar13® and Pneumo23®. Serotype-specific IgG was measured by ELISA for all 23 vaccine serotypes at baseline, and then sequentially at different time points postvaccination until treatment ended. Response to vaccination is available for 20 patients. The primary endpoint was the incidence rate of patients who obtained an isotype response serum concentration after vaccination. Secondary endpoints included detailed isotype increase, time to first increase, further assessment of a decreased anti-pneumococcal serum concentrations following treatment including autologous stem cell transplantation (ASCT), rate of infection with a special attention to pneumococcal infection. RESULTS: The median age was 66 years and the male to female ratio was 0.6. Anti-pneumococcal capsular polysaccharide (anti-PCP23) IgG, IgG2, IgA, and IgM responses were detected within 1 week postvaccination. Response to at least one subtype of antibody was obtained in 85% (n = 17) of patients, for at least two subtypes in 65% (n = 13), for at least three subtypes in 55% (n = 11), and 2 patients responded to all four subtypes. The median increase in the concentration of anti-PCP23 isotypes was threefold following vaccination, with the highest increase observed when Pneumo23® was given more than 30 days after Prevnar13®. The anti-pneumococcal geometric mean concentration decreased significantly for all subtypes over time independently of treatment approaches. CONCLUSION: Myeloma has the ability to demonstrate a response to pneumococcal vaccine, independently of preexisting hypogammaglobulinemia and possibly of treatment-induced immunodepression. We also observed a drop in the serum response overtime and following autologous transplantation. Further studies in larger sample are needed to understand the benefit of vaccination strategies in these patients.

Heavy + light chain analysis to assign myeloma response is analogous to the IMWG response criteria.

Automated serum heavy + light chain (HLC) immunoassays can measure the intact immunoglobulins of each light chain type separately. We though to compare HLC assays with electrophoretic techniques in determining International Myeloma Working Group (IMWG) response criteria. 114 myeloma patients from 2 trials were included. HLC measurements were made utilizing archived sera and response assessments compared with those based on electrophoretic analysis at the time of the trials. Assessments at ∼90 days and maximal response were compared as was the power of the 2 techniques for predicting later responses, overall survival, and progression. The kappa statistic indicated good agreement between the 2 methods for determining IMWG response criteria, although HLC measurements might give better predictions of subsequent responses and frequently gave an earlier indication of change. HLC measurements could represent an alternative to electrophoretic techniques in determining IMWG response. Validation with a greater range of patient responses is needed for confirmation.