Witzig, Thomas E.

Abstract Abstract 2634 The peripheral blood absolute lymphocyte/monocyte ratio (ALC/AMC) at diagnosis has been recently reported [Porrata et al, Hematologica 2012; 97(2):262-9] and confirmed [Koh et al, Oncologist 2012; 17(6):871-80] to be a predictor of clinical outcomes in classical Hodgkin lymphoma (HL). In addition, an inversed correlation has been reported between the ALC/AMC ratio and tumor associated macrophages in classical HL suggesting an association between the host biological response in the macro-environment and micro-environment. However, a limitation of the ALC/AMC ratio at diagnosis, the International Prognostic Score at diagnosis, the Positron-Emission Tomography (PET-scan) at diagnosis, or interim PET-scan during treatment is their inability to sequentially assess the host/tumor interaction during treatment. Therefore, we studied the ALC/AMC ratio recovery, as a surrogate marker of host immunity (i.e., ALC) and tumor micro-environment (i.e., AMC), at each treatment cycle phase to assess its predictive ability for clinical outcomes in classical HL. To participate in the study, patients were required to be diagnosed, treated, and followed at Mayo Clinic, Rochester, Minnesota and treated with adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD) with or without radiation therapy. An ALC/AMC ratio ≥ 1.1 cut-off was used in the study based on our previous publication [Porrata et al, Hematologica 2012; 97(2):262-9]. From 1990 until 2008, 190 classical HL patients qualified for the study. The cohort was evenly split with 50% males and 50% females. Fifty-eight percent of the patients had an interim PET-scan performed. The median age at diagnosis was 36 years (range: 18–83 years). Seventeen patients received 2 cycles; 5 patients 3 cycles; 51 patients 4 cycles; 5 patients 5 cycles and 112 patients 6 cycles. The median follow-up was 3.7 years (range: 0.2–20 years). The ALC/AMC ratio ≥ 1.1 at each treatment cycle phase of ABVD was a predictor for overall survival (OS), lymphoma-specific survival (LSS), progression-free survival (PFS) and time to progression (TTP). Patients were stratified based on how many cycles the ALC/AMC ratio did not reach the cut-off of 1.1. The more cycles with an ALC/AMC < 1.1 the worse survival was observed. The 23 patients who did not achieve an ALC/AMC ≥ 1.1 during the treatment cycles phase experienced the worst survival rates: 5 year OS of 33%; 5 year LSS of 43%; 5 year PFS of 16%; and 5 year TTP of 27%. Patients were then dichotomized into patients that did not achieve an ALC/AMC ratio ≥ 1.1 for all the cycles versus patients with an ALC/AMC ratio ≥ 1.1 in any cycle during treatment. Patients with an ALC/AMC ratio ≥ 1.1 in any cycle (N=167) experienced better survival compared with patients that in all cycles the ALC/AMC ratio was < 1.1 [ OS, the hazard ratio(HR) was 0.09, 95% CI (0.04–0.19), p < 0.0001; for LSS, HR =0.07, 95% CI (0.02–0.17), p <0.0001; for PFS, HR = 0.08, 95%CI (0.04–0.14), p < 0.0001; and for TTP, HR = 0.05, 95% CI (0.02–0.11), p < 0.0001]. In the multivariate analysis, an ALC/AMC ratio ≥ 1.1 in any cycle versus none was an independent predictor for clinical outcome when compared to ALC/AMC ratio at diagnsosis, PET-scan, International Prognostic Score, limited verus advanced stage, and radiation therapy [OS, HR = 0.14, 95% CI (0.04–0.40), p< 0.0002; for LSS, HR = 0.09, 95% CI (0.01–0.37), p <0.0006); for PFS, HR = 0.19, 95% CI (0.05–0.82), p < 0.03); and for TTP, HR = 0.15, 95% CI (0.02–0.89), p < 0.02]. In conclusion, the ALC/AMC ratio during ABVD treatment cycles in classical HL is a predictor for survival and provides an opportunity to develop therapeutic modalities to manipulate the ALC/AMC ratio during ABVD chemotherapy to improve clinical outcomes in classical HL. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 287 Purpose: Farnesyltransferases are key cellular enzymes involved in the prenylation of proteins. Prenylated proteins are important for malignant cell growth. The purpose of this phase II study (NCT00082888) was to assess tumor response and toxicity associated with the oral farnesyltransferase inhibitor tipifarnib (R115777, Johnson and Johnson) in patients with relapsed aggressive, indolent, or uncommon lymphoma. The uncommon group included low incidence lymphoma types such as Hodgkin lymphoma (HL) and T-cell non-Hodgkin lymphoma- cutaneous T-cell lymphoma (CTCL) and peripheral T-cell lymphoma (PTCL). Patients and Methods: Patients with relapsed or refractory non-Hodgkin (NHL) or Hodgkin (HL) were eligible if they had measurable disease, performance status ≤2, platelet count ≥75,000 × 10(6)/L, an absolute neutrophil count ≥1000 × 10(6)/L and a creatinine ≤2 × upper limit of normal. Patients initially received tipifarnib 300 mg twice daily, days 1–21 every 28 days. The trial was conducted by the University of Iowa/Mayo Clinic Lymphoma SPORE. Results: Ninety-three patients with lymphoma (42 aggressive, 15 indolent, and 36 uncommon) enrolled in the trial between March 2004 and November 2008. The median age was 62 years (range, 18–91). The median number of prior therapies was 5 (range, 1–17). The overall response rate (ORR) was 20% (19/93) with 6% (6/93) complete responses (CR) and 14% (13/93) partial responses (PR). The ORR was 17%, 7%, and 31% for the aggressive, indolent, and uncommon groups, respectively (Table). Among the 19 responders were 7 diffuse large B-cell lymphoma (DLBCL), 7 T-cell NHL, 1 follicular grade II, and 4 HL. The overall median response duration for the 19 responders was 7.5 months (mean, 12.8; range, 1.8 – 48.1 months). The median response duration was 11.3 months (mean, 10.1; range, 1.8 – 18.5 months), 2 months, and 7.5 months (mean, 15.5; range, 1.9 – 48.1 months) for the aggressive (7), indolent (1), and uncommon (11) groups, respectively. Five patients in the uncommon group are still receiving treatment with a range of treatment duration between 25 – 60+ months. Among the 5 still receiving treatment 4 responded and 1 is stable. The range of response duration is 15.4, 17.7, 43.1, and 48.1 months. These five patients (2 with HL, 1 anaplastic large cell cutaneous, and 2 PTCL) are currently receiving doses of 400 (1), 200 (2), and 100 (2) mg twice daily. The median time to progression for all patients was 3.6 months (95% CI: 2.1 – 4.5 months). The grade 3,4 toxicities observed were primarily fatigue (10%) and reversible myelosuppression with 11% anemia, 37% neutropenia, and 32% thrombocytopenia. Correlative studies demonstrated tipifarnib-induced upregulation of Bim, a marker of tipifarnib action in lymphoma cell lines, in 7 of 9 paired lymphoma biopsies. Conclusions: Tipifarnib has activity in lymphoma, with responses in patients with heavily pretreated DLBCL, HL and T-cell types, but little activity in follicular NHL. This agent has an excellent toxicity profile and targets a novel pathway. Further studies in combination with other agents are warranted for patients with DLBCL, HL or T-cell NHL. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 3053 Background: Patients with smoldering multiple myeloma (SMM) have a higher chance of progression to active MM than patients with monoclonal gammopathy of undetermined significance (MGUS). Since active MM remains incurable and since patients with SMM can have a long time to requiring treatment, observation remains an option for these patients. Bisphosphonates can prevent the bone complications of myeloma. The immunomodulatory (IMiD) drugs are well-tolerated and have documented anti-tumor activity in active MM. We hypothesized that treatment with the IMiD THAL and a bisphosphonate (ZLD) would prolong the time to progression (TTP) over the control arm of ZLD alone. This is the first report of this phase III trial of THAL/ZLD vs ZLD alone for patients with untreated SMM. Goals: The primary goal of this trial was to compare the TTP between patients treated with THAL/ZLD versus ZLD alone in asymptomatic MM. Secondary goals were progression rate at one year, response rate, duration of response, time to next therapy, and toxicity. Methods: Patients were required to have measurable disease as defined by either a serum monoclonal protein >1.0 g by protein electrophoresis or nephelometry or >200 mg of monoclonal protein in the urine on 24 hour electrophoresis or a measurable soft tissue plasmacytoma; >10% plasma cells as measured on the bone marrow aspirate, bone marrow biopsy, or labeling index; absolute neutrophil count >1500/μL; platelet count >100,000/μL; creatinine <2.0 mg/dL, and a performance status of 0, 1, or 2. Patients could not have symptomatic MM that required chemotherapy. The statistical plan was to accrue 120 eligible patients (60 per arm) over 4 years and after a minimum follow-up of 12 months the study would provide >90% power at a type I error rate of 0.05 to detect an increase in the median TTP from 12 months (ZLD) to 24 months (THAL/ZLD), and >80% power to detect an increase in median TTP from 12 to 21 months). Results: The study was activated in July 2003 and closed March 2009 due to slow accrual. Sixty-eight patients (35 Thal/ZLD; 33 ZLD) with a median age 63 years (range, 47–84) were randomized. The median TTP for Thal/ZLD versus ZLD was 2.4 years versus 1.2 years, respectively, P=0.02 one-sided log-rank. After adjusting for pre-specified stratification factors, the hazard ratio for TTP was 2.2 (one-sided p value = 0.01, univariate stratified Cox PH model) for ZLD compared to Thal/ZLD. 89% of patients on the Thal/ZLD arm were progression-free survival (PFS) at one year compared to 55% on ZLD alone (one-sided p<0.001, chi-square). Similar results were obtained (Table and Figures) when the CRAB (calcium, renal, anemia, bone) criteria were applied. Confirmed response was evaluated using the first 12 months of treatment. In the Thal/ZLD arm the response rate was 31% with a median duration of response of 5.1 years (95% CI: 1.9 - NA). There were no confirmed responses in the ZLD alone arm. The median overall survival has not been reached for either arm. In regards to toxicity, no grade 5 adverse events (AEs) have been reported. Thirty patients have reported grade 3+ AEs (17 Thal/ZLD; 13 ZLD, Fisher's exact p-value 0.47). Eight patients have reported grade 4 adverse events (5 Thal/ZLD; 3 ZLD, Fisher's exact p-value 0.71). Overall, only one grade 4 event was felt to be at least possibly related to study treatment – grade 4 neutropenia in Thal/ZLD. Conclusions: While the trial did not meet its planned accrual goals, there was a significant improvement in improved in outcomes in the Thal/ZLD arm compared to control (ZLD). Thal/ZLD produces anti-tumor responses that are quite durable with the median response duration of over 5 years. ZLD alone did not produce any anti-tumor responses. This study indicates that a non-chemotherapy approach can be effective in SMM and may be a useful strategy to test in future studies. Disclosures: Off Label Use: Thalidomide for smoldering myeloma. Lacy:Celgene: Research Funding. Dispenzieri:Celgene: Honoraria, Research Funding; Binding Site: Honoraria. Kumar:Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding. Gertz:Celgene: Honoraria; Millennium: Honoraria.

Abstract Abstract 2408 Purpose: Vitamin D insufficiency is common globally and in the United States. Approximately 25–50% of patients seen in routine clinical practice have vitamin D levels below the optimal range with low levels linked to higher cancer incidence. Although vitamin D insufficiency is also related to inferior prognosis in some cancers, no data exists for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL). Patients and Methods: To test the hypothesis that vitamin D levels predict outcome in patients with CLL, we evaluated the relationship of 25 (OH)D serum levels with time-to-treatment (TTT) and overall survival (OS) in 390 newly diagnosed CLL patients participating in a prospective cohort study (discovery cohort) and separate cohort of 153 previously untreated patients participating in an observational study (confirmation cohort). 25 (OH)D levels were measured by liquid chromatography-tandem mass spectrometry. Intra- and inter-assay coefficients of variation were all <7% (data not shown). All vitamin D assays were performed on stored research samples; results were not included in the clinical record and were not known to the treating physicians in either study. Vitamin D insufficiency was defined as a serum 25 (OH)D level <25 ng/mL (62.5 nmol/L), an accepted level3 for the establishment of hypovitaminosis D and the threshold used in routine clinical practice to identify individuals with 25 (OH)D insufficiency by our laboratory in routine clinical practice (http://www.mayomedicallaboratories.com). Results: We evaluated the relationship of 25 (OH)D serum levels with time-to-treatment (TTT) and overall survival (OS) in newly diagnosed CLL patients participating in a prospective cohort study (discovery cohort) and a separate cohort of previously untreated patients participating in an observational study (confirmation cohort). Of 390 CLL patients in the discovery cohort, 119 (30.5%) were 25 (OH)D insufficient. 25 (OH)D insufficiency had no relationship with CD38, ZAP-70, CD49d or IGHV mutation status and had no relationship with FISH risk category as classified using the Dohner system. After median follow-up of 3 years, TTT (hazard ratio [HR]=1.66; p=0.005) and OS (HR=2.39; p=0.01) were shorter for 25 (OH)D insufficient patients (figure). We next attempted to validate these findings in an independent group of previously untreated CLL patients. In the validation cohort, 61 of 153 patients (39.9%) were 25 (OH)D insufficient. After median follow-up of 9.9 years, TTT (HR=1.59; p=0.05) and OS (HR 1.63; p=0.06) were again shorter for 25 (OH)D insufficient patients. On pooled multivariable analysis of patients in both cohorts adjusting for age, sex, stage, CD38, ZAP-70, IGHV, CD49d, and FISH, 25 (OH)D insufficiency remained an independent predictor of TTT (HR=1.47; p=0.008). On multivariable analysis for OS, the HR for death associated with 25 (OH)D insufficiency was similar to univariate findings although the p value did not reach the threshold of statistical significance (HR=1.47; 95% CI=0.97–2.23; p=0.07). Conclusion: 25 (OH)D insufficiency is associated with inferior TTT and OS in CLL patients. Whether normalizing vitamin D levels in deficient CLL patients would improve outcome merits clinical testing. Disclosures: Zent: Genzyme: Research Funding; Genentech: Research Funding; Novartis: Research Funding; G.S.K.: Research Funding.

Abstract Abstract 136 Background: The serum free light chain (FLC) assay quantitates free kappa and free lambda immunoglobulin light chains. This assay has prognostic value in MGUS, multiple myeloma (MM), solitary plasmacytoma, and AL amyloidoisis, and has been incorporated in response criteria for both MM and AL amyloidosis. A percentage of non-Hodgkin's lymphoma (NHL) patients also present with abnormal FLC concentrations and recent data suggest that AIDS patients with elevated serum FLC are at higher risk of developing NHL. Here we assess the impact of FLC in a cohort of patients with diffuse large B-cell lymphoma (DLBCL) enrolled on a cooperative group clinical trial. Methods: Newly diagnosed DLBCL patients were treated with epratuzumab + R-CHOP (ER-CHOP) on NCCTG clinical trial N0489. Serum FLC was quantitated prior to treatment and after cycles 2 and 6 using the Freelite FLC assay (The Binding Site, Ltd., Birmingham, UK). Patients were followed per clinical trial protocol for event-free (progression, retreatment, or death due to any cause) and overall survival (EFS and OS, respectively). Results: 107 patients were enrolled on the trial. 80 patients had a pre-treatment serum draw and a central pathology confirmed diagnosis of DLBCL, of which 47 had a post-cycle 2 sample (C2) and a 54 had a post-cycle 6 sample (C6). At a medium follow-up of 25 months (range 7-39), 22 patients (28%) had an event and 17 patients died (21%). Prior to treatment 23 patients (29%) had abnormal kappa concentrations (all elevated), 16 (20%) had abnormal lambda concentrations (11 elevated, 5 decreased), and 9 (11%) had an abnormal kappa/lambda ratio. FLC concentrations were significantly reduced in patients during treatment, with a median reduction in kappa (C2: 46%, C6: 64%) and lambda (C2: 44%, C6: 49%), all p<0.0001. Elevated FLC prior to treatment was highly associated with both OS (logrank p=0.009) and EFS (logrank p=0.006); these associations remained significant after adjusting for IPI (both p = 0.01). Conclusions: A significant percentage of DLBCL patients present with abnormal FLC concentrations. Kappa and lambda are significantly reduced for most patients during treatment. Elevated pre-treatment FLC concentrations are associated with inferior EFS and OS in DLBCL and this association is independent of the IPI. A follow-up study of FLC and prognosis is currently underway in a cohort of 1500 NHL patients from the Mayo Clinic and University of Iowa SPORE. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 1952 Poster Board I-975 Background: Vitamin D is a naturally occurring steroid hormone. In addition to its well-established role in maintaining serum calcium homeostasis, vitamin D has effects on cellular differentiation, proliferation, apoptosis, and angiogenesis. Vitamin D3 is naturally produced in skin in response ultraviolet-B (UVB) radiation from the sun. Several recent studies, however, have shown that a high proportion of community-dwelling subjects in both tropical and temperate climates are deficient in vitamin D, and that subjects in northern latitudes often require dietary supplementation to maintain vitamin D sufficiency. Further, several reports now suggest that vitamin D sufficiency is protective against the development of several cancers, including non-Hodgkin lymphoma (NHL). However, it is not known whether vitamin D impacts prognosis in diffuse large B-cell lymphoma (DLBCL), the most common NHL subtype. Methods: We evaluated serum vitamin D concentrations in two cohorts of DLBCL patients. The first cohort consisted of 374 patients newly diagnosed from September 2002-February 2008 who were prospectively enrolled in the University of Iowa/Mayo Clinic Lymphoma SPORE Molecular Epidemiology Resource, an observational study in which neither therapeutic nor diagnostic management is prescribed. All serum was obtained within 120 days of diagnosis, and was prior to treatment in 221 (59%). In the second study, 62 patients newly diagnosed from February 2006-August 2007 were enrolled on NCCTG clinical trial N0489, and all serum was obtained before the first course of therapy. Central pathology review was performed on all patients to confirm the diagnosis of DLBCL. Serum 25-hydroxyvitamin (25-OH-VitD) levels were measured by the gold standard method for vitamin D determination: liquid chromatography tandem mass spectroscopy (LC-MS/MS). Vitamin D deficiency was defined as total serum 25-OH-VitD < 25 ng/mL (62.5 nmol/L). SPORE patients were followed per a standard protocol for event-free (progression, retreatment, or death due to any cause) and overall survival (EFS and OS, respectively); N0489 patients were followed in a similar way per the clinical trial protocol. We used Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CI). Results: SPORE patients were primarily treated with immunochemotherapy (83%); all N0489 patients were treated with epratuzumab + R-CHOP21. The median age at diagnosis was 62 years (range, 19-93) for SPORE patients and 61 years (range, 21-82) for N0489 patients. Median follow-up for SPORE patients was 36 months (range, 1-77) with 95 deaths and 131 events; median follow-up for N0489 patients was 24 months (range, 7-39) with 13 deaths and 18 events. Vitamin D deficiency was identified in 188 SPORE patients (50%) and 15 N0489 patients (24%). There were no differences in the prevalence of vitamin D deficiency by age, IPI, or whether serum was obtained prior to starting treatment (all p > 0.28). Vitamin D deficiency was associated with inferior overall (HR=2.33, 95% CI 1.53-3.57, logrank p = 0.0001) and event-free survival (HR=1.71, 95% CI 1.20-2.44, logrank p = 0.003) in the SPORE cohort. These associations remained significant after adjusting for IPI and treatment: OS HR=1.97, 95% CI 1.27-3.07; EFS HR=1.47, 95% CI 1.02-2.21. These results were similar for the subset of SPORE patients who were treated with R-CHOP. The HRs for vitamin D deficiency and event-free survival were consistent in the N0489 patients (HR=1.63, 95% CI 0.61-4.35, IPI adjusted HR=1.43, 95% CI 0.53-3.85), although these results lacked precision due to a smaller sample size. We were unable to evaluate OS in N0489 due to the small number of deaths. Conclusions: Approximately 50% of all DLBCL patients in this northern US latitude population are vitamin D deficient at the time of diagnosis and treatment. Vitamin D deficient patients have an inferior event-free and overall survival compared to patients with vitamin D levels within the normal range. Vitamin D supplementation during treatment of DLBCL patients with vitamin D deficiency should be evaluated in a clinical trial setting. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 137 Background: FDG-PET/CT after 2–4 cycles of chemotherapy has been shown to be predictive of outcome in patients with aggressive lymphoma. This multicenter NCCTG phase II study was carried out to assess efficacy of ER-CHOP in newly diagnosed DLBCL; functional response as measured by FDG-PET/CT was done after 2 cycles and after 6 cycles of therapy. Methods: Patients received immunochemotherapy on the following schedule: epratuzumab 360 mg/m2, rituximab 375 mg/m2, and standard dose CHOP every 3 weeks for 6 cycles. FDG-PET/CT was done after 2 cycles and again after 6 cycles of therapy. All PET scans were centrally reviewed by an expert in nuclear medicine who was blinded to the outcome of the patients. Results: 107 patients were accrued from Feb 2006 to Aug 2007. 27 patients were ineligible resulting in 80 eligible patients. Baseline patient characteristics for the eligible patients included median age 60 (range 21–82); 56% were male. 80% had advanced stage; 73% had an elevated LDH. Performance score was 0–1 in 71 pts and 2–3 in 9 pts. IPI was 0–1 in 18 pts (23%), 2 in 22 pts (28%), 3 in 29 pts (36%) and 4–5 in 11 pts (14%). PET scans were available on 76 patients (95%); 3 patients completed treatment but scans were unavailable and 1 died prior to cycle 2 PET. The PET CR rate after 2 cycles was 79%. The PET CR rate after 6 cycles was 90%. Using an intent to treat (ITT) analysis, 67 patients (87%) achieved PET CR of which 61 (79%) also completed all 6 cycles of treatment. Based on interim PET after 2 cycles, the EFS at 24 months (EFS24) was 73% for the PET negative patients vs 60% for the PET positive patients (p=0.25); OS at 24 months (OS24) was 83% vs 73% for the PET negative and positive pts, respectively (p=0.17). In comparison, EFS24 for patients with a negative PET after 6 cycles was 80% vs 57% for those with a positive PET (p=0.11); OS24 was 92% vs 57%, respectively (p=0.01). In intent to treat (ITT) analysis, patients that achieved a functional CR had improved overall survival (OS24 = 84%) and event free survival (EFS24 = 74%) compared to patients that failed to achieve a functional CR (OS24 = 50%, EFS24 = 40%, p=0.01 and p=0.006 respectively). Conclusions: ER-CHOP every 21 days × 6 cycles results in a functional CR rate of 87%. Early PET scan during therapy does not significantly predict outcome. Achievement of PET negativity by completion of therapy is associated with a good outcome Disclosures: No relevant conflicts of interest to declare.

Abstract Waldenstrom’s macroglobulinemia is a serious and frequently fatal illness, however many of the mechanisms leading to this disease are not yet known. It is clear, however, that there is dysregulation of the balance between cell proliferation and programmed cell death. BLyS (B-lymphocyte stimulator) is a newly identified TNF family member expressed by monocytes, macrophages, and dendritic cells. BLyS has been shown to be critical for maintenance of normal B cell development and homeostasis, and has been found to stimulate lymphocyte growth. BLyS is overexpressed in a variety of B-cell malignancies and has been shown to inhibit apoptosis in malignant B-cells. Studies of the effects of BLyS on B cell physiology have shown that it also regulates immunoglobulin secretion. To determine the relevance of the BLyS receptor-ligand system in Waldenstrom’s macroglobulinemia, we examined malignant B cells from 5 patients with Waldenstrom’s macroglobulinemia for their ability to bind soluble BLyS and for the expression of the known BLyS receptors, TACI, BAFF-R, or BCMA. The malignant B cells were found to bind BLyS and express BAFF-R and TACI. BCMA expression was undetectable. We then determined the expression of BLyS in bone marrow specimens from 5 patients with Waldenstrom’s macroglobulinemia by immunohistochemistry and compared it to the expression in 5 normal bone marrow specimens. The lymphoplasmacytic cell infiltrate in the bone marrow of patients with Waldenstrom’s macroglobulinemia showed significantly increased BLyS expression. We further determined the serum BLyS levels by ELISA in stored serum specimens from patients with Waldenstrom’s macroglobulinemia (n=20), and compared them to serum BLyS levels in other patients with lymphoplasmacytic lymphoma without elevated immunoglobulin levels (n=10) and to serum levels in normal controls (n=50). Serum BLyS levels in Waldenstrom’s patients (mean: 49.6ng/ml) as well as those in patients with lymphoplasmacytic lymphoma (mean; 46.7ng/ml) were significantly higher than normal controls (mean 12.6ng/ml). In conclusion, we have demonstrated that malignant B cells from patients with Waldenstrom’s macroglobulinemia express the receptors for BLyS and can bind soluble BLyS. Furthermore, we have found that serum BLyS levels are significantly elevated in patients with Waldenstrom’s macroglobulinemia when compared to controls. Strategies to inhibit BLyS may potentially have significant therapeutic efficacy in Waldenstrom’s macroglobulinemia.

Abstract Introduction Relapse in the central nervous system is an uncommon complication of diffuse large B cell lymphoma (DLBCL) associated with a poor prognosis. The addition of rituximab to chemotherapy has improved outcomes in patients with DLBCL but its effect on the outcome of patients with CNS relapse is not well characterized. Here we present the natural history of patients with CNS relapse in a large cohort of patients with DLBCL who were treated in the immunochemotherapy (IC) era. Methods Newly diagnosed patients with DLBCL or primary mediastinal B-cell lymphoma (PMBCL) and treated with primary anthracycline based IC were prospectively enrolled on the University of Iowa/Mayo Clinic SPORE Molecular Epidemiology Resource (MER) within 9 months of diagnosis and followed for relapse, retreatment, and death. Clinical management at diagnosis and subsequent therapies were per treating physician. Patients with documented CNS involvement at diagnosis, primary CNS lymphoma, or post-transplant lymphoproliferative disorder at diagnosis were excluded. All CNS relapse and retreatment details were verified by medical record review. Results 1017 patients with newly diagnosed DLBCL or PMBCL, no documented CNS disease at diagnosis, and treated with IC were enrolled in the MER between 2002 and 2012. At a median follow-up of 59 months (range 1-148), 36 patients had CNS relapse. The cumulative incidence of CNS relapse was 3.1% (95% CI: 2.2%-4.4%) at 2 years and 3.7% (95% CI: 2.7%-5.0%) at 5 years after diagnosis. CNS involvement was identified after first line IC in 25 patients, and after salvage therapy in 11 patients. 22 patients had an isolated CNS relapse, while 14 had both systemic and CNS disease at relapse. The incidence of isolated CNS relapse at two years from diagnosis was 1.9% (95% CI: 1.2%-3.0%, figure 1). CNS involvement was parenchymal in 22 patients, leptomeningeal in 11, and parenchymal and leptomeningeal in 3 patients. At diagnosis, this subset of 36 patients had a median age of 61 years (range 20-86); 25 (69%) were male. IPI was 0-1 in 6 patients, 2 in 13 patients, 3 in 11 patients and 4-5 in 6 patients. Cell of origin per Hans algorithm was available in 17 patients, 8 were GCB and 9 were non-GCB. Extranodal sites of disease at diagnosis included testicular (2), renal (5), bone (10) and bone marrow (6). 7 patients had no sites of extranodal disease. LDH was elevated in 71%. The German High-Grade Non-Hodgkin Lymphoma Study Group CNS risk score was low risk in 6 patients, intermediate risk in 22 patients, and high risk in 8 patients. 6 patients received CNS prophylaxis with their initial immunochemotherapy, including 3 of the 21 patients who subsequently developed isolated CNS disease. First line therapy after CNS relapse included high dose methotrexate based chemotherapy in 22 patients and other systemic regimens in 6, with intrathecal (IT) chemotherapy in 5. Overall survival in patients after CNS relapse was poor with a median survival of 6.3 months (95% CI: 2.9-15.5) and 12-month survival rate of 29% (95% CI: 17%-49%). Patients who had CNS relapse following initial IC had better subsequent survival (median OS = 7.6 months) compared to patients with first presentation of CNS relapse following salvage therapy (OS = 2.1 months, p=0.005, see figure 2). 10 patients (28%) proceeded to SCT after CNS relapse, of which 6 remain alive at a median follow-up of 39 months. There were no differences in post-CNS relapse survival by age, sex, CNS risk score, cell of origin, extranodal site involvement at diagnosis, or site of CNS relapse (all p>0.10), though power was limited due to small numbers. Conclusions The incidence of CNS relapse in DLBCL is approximately 4% in the immunochemotherapy era. The vast majority of CNS relapses occur within 2 years of diagnosis. Isolated relapse in patients without CNS involvement at diagnosis is a relatively rare event with an incidence of approximately 2% at 2 years of diagnosis. Outcomes remain poor, and standard clinical variables do not predict survival after CNS relapse. Novel therapeutic approaches are needed in this population, with consideration to autologous SCT, which produces durable remission in a subset of patients. Disclosures Maurer: Kite Pharma: Research Funding. Farooq:Kite Pharma: Research Funding. Thompson:Kite Pharma: Research Funding. Ansell:Bristol-Myers Squibb: Research Funding; Celldex: Research Funding. Cerhan:Kite Pharma: Research Funding. Link:Genentech: Consultancy, Research Funding; Kite Pharma: Research Funding.

Abstract Abstract 2862 Follicular lymphoma (FL) is a B-cell malignancy that exhibits significant intratumoral infiltration by non-malignant T lymphocytes. The pathophysiological significance of infiltrating T cells is poorly understood but recent studies have suggested that CD4+CD25+ regulatory T (Treg) cells are highly represented in lymph nodes involved by FL. These Treg cells display the ability to suppress the proliferation and cytokine production of other tumor-infiltrating T cells and migrate to areas of B-cell lymphoma in response to chemotactic signals provided by the malignant B-cells. Denileukin diftitox, a chimeric immunotoxin composed of the modified cytotoxic domain of diphtheria toxin and human interleukin-2 (IL-2) protein, targets cells expressing CD25 and has proven efficacy in patients with relapsed B-cell lymphoma. In this study, we combined denileukin diftitox with rituximab in a cohort of previously untreated, advanced-stage follicular lymphoma patients. Our hypothesis was that denileukin diftitox would deplete the Treg cells, thereby removing the inhibition of the immune response, and rituximab would deplete the B-cells thereby preventing further recruitment of Treg cells to the areas of lymphoma. Between August 2008 and March 2010, twenty-four patients with stage III and IV follicular grade 1 or 2 non-Hodgkin lymphoma were accrued to the study. One patient died before treatment was given and is not included in the analysis. The median age was 60 years (range: 27 – 79), 12 (52%) of the patients were male, 19 (83%) had a PS of 0 and 4 (17%) had a PS of 1. Based on the Follicular Lymphoma International Prognostic Index (FLIPI), 3 (13%) were low risk, 14 (61%) were intermediate risk and 6 (26%) were high risk. Patients received rituximab 375 mg/m2 on days 1, 8, 15 and 22 and denileukin diftitox 18 mcg/kg/day on days 1–5 every 3 weeks for 4 cycles. A median of 4 cycles of therapy was given (range: 1 – 4). Thirteen patients completed treatment per protocol (57%), however 5 patients discontinued treatment due to adverse events (22%), 2 refused further treatment (9%) and 1 discontinued due to disease progression (4%). Nine of the 23 patients (39%; 95% CI: 21–61%) responded to treatment, 3 (13%) had a complete response and 6 (26%) had a partial response. Twenty-one patients (91%) are alive with a median follow-up of 8.7 months (range: 3.4–19.5). Seven (30%) patients have progressed and two (8.7%) has died. The median time to progression is 13.4 months (95% CI: 10.4 – NA). The combination, however, was associated with significant toxicity. Thirteen patients (57%) experienced grade 3 or greater adverse events. Six patients (26%) had symptoms of capillary leak syndrome, 1 of whom died. In correlative studies performed on the peripheral blood, the number of CD25+ T-cells decreased after treatment when compared to pretreatment numbers (median 24%; range: 8–44%). We conclude that while the addition of denileukin diftitox to rituximab decreased the numbers of CD25+ T-cells, denileukin diftitox contributed significantly to the toxicity of the combination. Furthermore, the overall response rate and time to progression in this study were no better than what would be expected in follicular lymphoma patients treated with rituximab alone. Disclosures: No relevant conflicts of interest to declare.