Citations

Abstract Abstract 2463 The treatment of relapsed/refractory B-Chronic Lymphocytic Leukemia (CLL) is difficult in terms of both inducing meaningful responses and being able to predict clinical outcome. In an attempt to address the latter aspect, we analyzed a battery of prognostic parameters obtained from a cohort of relapsed/refractory CLL patients entered onto ECOG trial E2903. This protocol included 2 steps: an induction phase (step 1) with pentostatin (4 mg/m2), cyclophosphamide (600 mg/m2), and rituximab (375 mg/m2) given every 3 weeks for 6 cycles and a consolidation phase (step 2) where complete responders (CR) were given 4 weeks of subcutaneous (sc) alemtuzumab (30 mg/m2, 3 times a week) or patients attaining partial response (PR), stable or progressive disease were given 18 weeks of sc alemtuzumab. Sixty-five eligible patients were enrolled; median age was 63 yr; male to female ratio of 4:1; median (range) number of prior therapies was 3 (1–7); and there were 16, 7, and 40 patients in Rai 0–1, Rai 2; and Rai 3–4 stages respectively. The median serum β-2 microglobulin was 4 (1–28). The overall response rate for step 1 in this cohort was 46% with 1 complete and 29 partial responses and 38.5% judged as having stable disease. Strict CR criteria, including CT imaging were utilized, demonstrating the infrequency of total response using CT scans. For traditional prognostic parameters, we found that age over 70 yr and high Rai risk stage (3–4) did not preclude a clinical response, but there was a significant difference between responders and non-responders in serum β-2 microglobulin levels (p=0.03). For molecular prognostic parameters, we found that the immunoglobulin variable heavy chain region (IGVH) mutational status did not preclude a lack of clinical response. However, for patients who were ZAP70 negative (−) or CD38 negative (−) these factors were positively associated with clinical response (p=0.046, 0.0005, respectively). The sensitivity in predicting a clinical response was 82% in ZAP70- and 73% in CD38-. In multivariable logistic regression analysis, only CD38 was significantly associated with response (Odds Ratio: 41, p=0.002). When patients were segregated into low (13q- or normal), intermediate (Trisomy 12) and high risk FISH (17p-,) there was no association with clinical outcome. In addition, if patients' CLL cells were unmutated and high risk FISH, there was no reduced clinical response. Of 65 patients included in this analysis, the 2-year overall survival (OS) was 55% (±7%) and the 2-year progression-free survival (PFS) is 25% (± 6.6%). The median follow-up time amongst survivors was 23 (range 6–60) months. The univariable analysis for PFS revealed that the IGVH mutated (2-yr PFS 53% for mutated vs. 18% for unmutated, p=0.037, Figure) and low risk FISH (2-yr PFS 42% for low risk vs. 23% for high risk, p=0.04) were significant. However, only IGVH mutated was significant (HR 0.33, p=0.027) for PFS in multivariable Cox model. In univariable analysis for OS, the combination of age <70 yr and β-2 microglobulin<2 upper limits [UL] was significant (2-yr OS: 68% vs. 39%, p=0.048), whereas only β-2 microglobulin was significant (HR 3.45 for >=2UL vs. <2UL, p=0.02) in multivariable Cox model. A total of 24 patients entered onto step 2 of the consolidation phase, receiving alemtuzumab; 17 patients who were responders from step 1 entered onto the 4 weeks of step 2; and 7 of the non-responders went onto the 18 weeks of step 2. The 2-year OS of these 24 patients was 62% from the date of consolidation phase: 61% for 17 responding patients to PCR and 60% for non responders to PCR (p=0.87). Current conclusions of this study are: (1) heavily pretreated high risk CLL patients may still have a respectable survival with the PCR combination; (2) β-2 microglobulin, ZAP70, and CD38 were important factors associated with response to PCR; (3) both IGVH mutated and FISH were prognostic markers associated with PFS; (4) addition of alemtuzumab may confer comparable survival rates for PCR non responders to the responders; (5) β-2 microglobulin was the only prognostic factor significant for OS. In total this study shows that both traditional and molecular markers can be used to predict clinical outcome for high risk relapsed/ refractory CLL patients treated with chemoimmunotherapy. We anticipate further valuable prognostic information to come from this still accruing study. Progression Free Survival post PCR for IGVH patients as separated by Unmutated (UM) or Mutated cohorts Progression Free Survival post PCR for IGVH patients as separated by Unmutated (UM) or Mutated cohorts Disclosures: Rosen: Genentech: Speakers Bureau.

Abstract Background: Over the last decade, increasing numbers of families with at least 2 cases of CLL or other B-cell lymphoproliferative disorders have been described. Methods: Families seen at Mayo Clinic with at least one individual diagnosed with CLL and one or more first or second degree relative diagnosed with CLL or a B-cell lymphoproliferative disorder(LPD) were identified. Clinical characteristics and risk stratification test results (cytogenetic abnormalities by FISH, level of CD38 expression, and IgVH gene mutation status) were extracted and reviewed. Serum, intracellular and CLL B cell secreted levels of pro- and anti-angiogenic cytokines (VEGF, BFGF, and TSP) were also compared between cases of familial and sporadic CLL. Results: Seventy-one families seen at Mayo Clinic were identified meeting criteria for familial CLL. Of the 71 index CLL families, 78.9% (n=56) had at least one other first or second-degree relative with CLL or a B cell LPD, 15.5% (n=11) had 2 other affected members, and 5.6% (n=4) had 3 or more affected members. Of affected family members with B-cell LPDs other than CLL, 64% (n=25) had non-Hodgkin lymphoma, 21% (n=8) had Hodgkin disease, 10% (n=4) had multiple myeloma or Waldenstrom macroglobulinemia, and 5% (n=2) had another lymphoid leukemia (1 ALL, 1 hairy cell leukemia). The median age was 62, with 63% males and 37% females. The majority of individuals had an early Rai stage at diagnosis (stage 0–66%, stage I-19%). Results of cytogenetic testing by FISH, CD38 status, IgVH gene mutation status appear similar in familial and sporadic CLL cases seen at Mayo clinic during the same time interval. No clear pattern of IgVH gene mutation status, IgVH gene family usage, level of CD38 expression, or cytogenetic abnormalities by FISH was seen among multiple affected members from the same family. There were also no significant differences noted in serum, intracellular, and CLL B cell secreted levels of VEGF, BFGF or TSP in the familial samples when compared to a cohort of non-familial samples. Conclusions: Expression of cytogenetics by FISH, immunophenotype, IgVH mutation status and levels of serum, intracellular and cytoplasmic pro- and anti-angiogenic factors(VEGF, BFGF, and TSP) were similar in individuals with familial and sporadic CLL.

Abstract Abstract 2406 The outcome for a given CLL patient is difficult to predict. While there are promising models, they require collation of multiple clinical and laboratory parameters, and it remains to be seen whether they will apply to typical CLL patients in the community. To further dissect out explanations for this dramatic clinical heterogeneity, we sought to understand genomic complexity of clonal B-cells as a possible explanation of clinical variability with specific application to genomic complexity as a predictor of therapeutic response and clinical outcome in CLL. Thus we wished to identified global gains and losses of genetic material in order to define copy-number abnormalities (CNA) in 48 clinically progressive CLL patients who were about to be treated on a chemoimmunotherapy protocol. This protocol was previously reported by us (Blood. 109:2007) and had an induction phase with pentostatin (2 mg/m2), cyclophosphamide (600 mg/m2) and rituximab (375 mg/m2) given every 3 weeks for 6 cycles and then responding patients were followed ever three months until relapse. In order to estimate CNA, we employed array-based comparative genomic hybridization (aCGH) using a one-million oligonucleotide probe array format on the leukemic B-cells from the 48 patients entering this trial. In those same patients, the aCGH data were compared to a) FISH detecxtable data using a panel for the common recurring genetic defects seen in CLL and b) to their clinical outcome on this trial. With aCGH we found that 288 CNA were identified (median of 4 per patient; range 0–32) of which 215 were deletions and 73 were gains. The aCGH method identified most of the FISH detected abnormalities with a complete concordance for 17p13.1- deletion (17p-) between aCGH and FISH. We also identified chromosomal gain or loss in ≥6% of the patients on chromosomes 3, 8, 9, 10, 11, 12, 13, 14 and 17. We found that CLL patients with ≥15 CNA had a significantly worse progression free survival (PFS) than patients with <15 CNA (p=0.004)(figure). Patients with ≥15 CNA also had a shorter duration of response than those with <15 CNA (p=0.0726). Of interest, more complex genomic features were found both in patients with a 17p13.1 deletion and in more favorable genetic subtypes such as 13q14.1. Thus, for 5 patients with >15 CNAs the following FISH patterns were seen: +12/13q14.1-x1/13q14.1 -x2, 13q14.1 ×1 (n=2), and 17p13.1 (n=2). In addition, a 17p- by FISH was positively associated with the number of CNA and total deletion size. The odds of having an overall response decreased by 28% (95% CI: 5–55%; p=0.015) with each additional CNA for the 17p13.1- patients. In addition to defining genomic complexity as the total number of CNA for each patient, we also defined complexity as the sum of the lengths of all interstitial chromosomal gains and losses. When defined as the total size of chromosomal gains or losses, genomic complexity was significantly associated with 17p13.1 and worse overall clinical response. In summary, this analysis utilized the global assessment of copy number abnormalities using a high-resolution aCGH platform for clinically progressive CLL patients prior to initiation of their treatment. One outcome was that we found higher genomic complexity was associated with shorter progression-free survival, reduced duration of response and predicted a poor response to treatment. In addition since we did find genomic complexity in more traditionally favorable FISH categories, such as 13q14.1 type defects, this may explain why some of the latter patients do not fare as well as might be expected even with aggressive chemoimmunotherapy approaches. This study adds information on the association between inferior trial response and increasing genetic complexity as CLL progresses. Disclosures: Off Label Use: Pentostatin. Kipps: GlaxoSmithKline: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Genentech: Research Funding; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Research Funding; Genzyme: Research Funding; Memgen: Research Funding; Igenica: Consultancy, Membership on an entity's Board of Directors or advisory committees; Sanofi Aventis: Research Funding; Abbott Laboratories: Research Funding.

Abstract Malignant B-cells characteristically home to the bone marrow and lymph nodes. However, the mechanisms by which cells are recruited into and mobilized from the bone marrow/lymph nodes into the peripheral blood are not well understood. Chemokines such as SDF-1 and it receptor CXCR4 play a central role for lymphocyte trafficking and homing. Downstream activation of the PI3K pathway by chemokines has been implicated in the migration of many cell types. We recently demonstrated that CXCR4 expression correlates significantly with disease progression in CLL. Patients with Rai stage 4 had a higher expression of CXCR4 when compared to patients with Rai stage 0. The expression of CXCR4 was not found on CLL B cells resident within the lymph nodes implying that there may have been downregulation of CXCR4. In this study, we explore the molecular mechanisms involved in homing and migration of B-CLL cells in response to CXCR4 and investigated the role of the PI3K pathway in migration of CLL cells in response to SDF-1. Boyden chamber in vitro migration assays were used with primary CLL peripheral blood cells and the MEK1 CLL cell line. In addition, we expressed fluorescent YFP-CXCR4 in the cells and used confocal microscopy to visualize changes in the subcellular location of the fluorescent CXCR4 before and after SDF-1 stimulation. Inhibitors of the PI3K pathway such as the PI3K inhibitor LY294002 (10uM, one hour pretreatment) and the mTOR inhibitor, rapamycin (200nM overnight) were used. SDF-1 induced a dose dependent migration of primary CLL cells and MEK1 cells, indicating functional CXCR4 receptors. MEK 1 cells transfected with YFP-CXCR4 demonstrated surface localization on the cells. 3-Dimensional and continuous live imaging after SDF-1 stimulation for 30 minutes demonstrated alterations in the CXCR4-YFP leading to its capping and internalization subcellularly. Pretreatment of the cells with PI3K pathway inhibitors led to inhibition of migration with LY294002 but not with rapamycin. Confocal microscopy demonstrated abrogation of subcellular localization in the presence of LY294002 but not with rapamycin with the addition of SDF-1. These results demonstrate that CLL cells express functional CXCR4 receptora and that the PI3K pathway is essential for SDF-1 dependent CLL migration. In addition, we demonstrate that the CXCR4 receptor is internalized in response to SDF-1 stimulation indicating that CLL cells downregulate the CXCR4 receptor once they home to the bone marrow or lymph nodes where there is abundant SDF-1 in the microenvironment. This leads to the confinement of the cells in the microenvironment preventing further migration of the cells outside of the bone marrow/lymph nodes. Supported in part by CA97274

Abstract Abstract 2409 Background: Serum free light chain (FLC) quantitation has prognostic value in MGUS, multiple myeloma (MM), solitary plasmacytoma, and amyloid light chain (AL) amyloidosis, and it has been incorporated in response criteria for both MM and AL amyloidosis. Two recent studies have shown FLC abnormalities are present in 39–54% of CLL patients and are associated with shorter time to treatment (TTT) and inferior overall survival (OS) in CLL. Here we report the largest study to date of FLC abnormalities in a prospective cohort of CLL patients and explore the effects of both monoclonal and polyclonal FLC elevations. Methods: Newly diagnosed CLL patients were prospectively enrolled in the University of Iowa/Mayo Clinic SPORE Molecular Epidemiology Resource (MER). Serum FLC was quantitated from stored research serum samples using the Freelite FLC assay (The Binding Site, Ltd., Birmingham, UK). Elevated FLC was defined as either kappa or lambda above the reference range (k>19.4 mg/L, l>26.3 mg/L). Monoclonal FLC elevation was defined as elevated FLC with an abnormal FLC ratio. Polyclonal FLC elevation was defined as elevated FLC with a normal FLC ratio (0.26–1.65). Patients with normal FLC but abnormal FLC ratio were evaluated as a distinct group (Abnormal FLC Ratio). Clinical data was abstracted using a standard protocol for the MER and patients were followed systematically for TTT and OS. Cox proportional hazards models were used to assess the association of FLC with TTT and OS. Results: 385 CLL patients diagnosed between September 2002 and February 2008 with available serum were assayed. At a median follow-up of 47 months (range 1–94), 135 patients (35%) have been treated and 43 patients have died (11%). Abnormalities in FLC were present in nearly half of the CLL patients (48.8%). Although 32.4% had an elevated kappa or lambda, only 14.0% had a monoclonal FLC elevation while the remaining 18.4% had a polyclonal FLC elevation. An additional 16.4% had an abnormal ratio without elevated FLC. Monoclonal FLC elevation was associated with high risk features of CD38+, CD49D+, ZAP70+, IGHV unmutated and having high risk FISH (del 17p13; del 11q22). Monoclonal FLC elevation was highly associated with shorter TTT (HR=3.24, p=0.0007) and poor overall survival (HR=4.14, p=0.0006). These associations remained statistically significant after adjusting for stage and prognostic factors. Abnormal FLC ratio without elevated FLC was also associated with shorter TTT (HR=1.74, p=0.03), though this association did not hold after adjustment for stage and prognostic factors. Polyclonal FLC elevations were associated high risk FISH and poor overall survival (HR=6.41, p<0.0001, adjusted HR = 4.82, p=0.0002) but not with TTT. Conclusions: In the largest series of newly diagnosed CLL patients reported to date, nearly half of CLL patients have abnormal FLC concentrations. Monoclonal FLC elevation is an independent predictor of shorter TTT and inferior overall survival in CLL, is associated with high risk markers, and may be a marker of an aggressive tumor. Polyclonal FLC elevation without abnormal FLC ratio is independently associated with poor overall survival but not TTT suggesting it may be a non-specific marker of host frailty/comorbidity rather than disease specific outcomes. Regardless of cause, CLL patients with elevated FLC have poor outcome and FLC may have utility as a biomarker in CLL. Disclosures: Zent: Genzyme: Research Funding; Genentech: Research Funding; Novartis: Research Funding; G.S.K.: Research Funding.

Abstract Abstract 2443 Background: There is strong and consistent evidence that a genetic component contributes to the etiology of chronic lymphocytic leukemia (CLL). A recent genome-wide association (GWA) study of CLL identified genetic variants located on chromosomes 2q13, 2q37.1, 6p25, 11q24, 15q23, and 19q13 that increased the risk of CLL within a European population. We replicated 5 of these 6 loci in an independent sample of CLL cases and controls from the United States. We now investigate whether these loci also influences MBL, a reported precursor condition of CLL. In addition, a follow-up analysis of the initial GWA study identified four more CLL-susceptibility loci on 2q37.3, 8q24.21, 15q21.3, and 16q24.1. Herein, we also evaluate the association of these four loci with risk of CLL. Methods: Peripheral blood samples were obtained from three ongoing studies: the Genetic Epidemiology CLL (GEC) Consortium, the Mayo Clinic non-Hodgkin lymphoma (NHL)/ CLL study, and the Mayo Clinic Biobank. We implemented rigorous genotyping quality-control measures, and successfully genotyped a total of 407 CLL patients, 965 controls, and 60 MBLs from these studies. Within each locus, the previously reported single nucleotide variants (SNPs) or variants in high linkage disequilibrium (LD) with the previously reported SNPs were evaluated with risk of MBL or CLL. Tests for association was done using the Cochran-Armitage trend test, and unconditional logistic regression was used to estimate odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for CLL or MBL risk Results: In our evaluation of the six initially reported CLL-susceptibility loci (2q13, 2q37.1, 6p25, 11q24, 15q23, and 19q13) with MBL risk, we found three of the six had suggestive associations (p-value < 0.20) with ORs comparable to and in the same direction as those observed from CLL risk. Our strongest finding was with rs13397985 at locus 2q37.1 (OR= 1.56; 95% CI: 1.05, 2.31; p-trend = 0.041), followed by rs17483466 at locus 2q13 (OR= 1.49; 95% CI: 0.99, 2.24; p-trend = 0.074). As expected given our previously reported findings with CLL risk, the association between rs11083846 on chromosome 19q13 and MBL risk was not significant (p-trend = 0.70). Of the four recently reported CLL-susceptibility loci SNPs located on 2q37.3, 8q24.21, 15q21.3, and 16q24.1, we found all to be associated with CLL risk but one. Specifically, the strongest association was seen for locus 8q24.21 (best tagged SNP rs1021955; OR = 1.37; 95% CI: 1.10, 1.70; p-trend = 0.005), followed by locus 16q24.1 (best tagged SNP rs305065; OR= 0.77; 95% CI: 0.61, 0.97; p-trend = 0.024). However, we found no associations for locus 15q21.3 for the previously reported SNP nor for any SNPs in LD with the previously reported SNP. Conclusions: Our MBL results provide additional robust genetic evidence that MBL is a precursor to CLL and that it shares similar underlying genetic predisposition. Also our results confirm three of the four recently reported CLL-susceptibility loci and further support the role of a genetic basis in the etiology of CLL. More research is needed to elucidate the potential manner in which these genetic loci function in CLL or MBL. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 2414 Background: Mesenchymal stromal cells (MSC) derived from normal subjects are known to have immunosuppressive capacity by virtue of inhibiting T- and B-cell activation. A novel subset of T cells, Th17, plays an important role in inflammation and autoimmunity. A recent report demonstrated that normal MSC ameliorates experimental autoimmune encephalomyelitis by inhibiting CD4+ Th17 cells in a chemokine ligand 2-dependent manner (J Immunol. 2009, 182: 5994). It remains unknown if MSC derived from leukemic or cancer patients play a role in Th17 cell differentiation. In particular this would be of interest to study in B-Chronic Lymphocytic Leukemia (CLL) where immunosuppression is evident even in early stage disease. Methods: MSC derived from bone marrow of CLL patients or normal subjects were expanded in vitro as previously described by us (Br J Haematol. 2009, 147:471). CD4+ cells positively selected from normal peripheral blood mononuclear cells were co-cultured with either CLL MSC or normal MSC at a ratio of 50:1 for 3 days with stimulation via CD3/CD28 beads, as well as interleukin-1β (IL-1β; 50 ng/ml). Then phorbol 12-myristate 13-acetate (50 ng/ml) and ionomycin (500 ng/ml) were introduced into the co-culture for 5 hrs in the presence of brefeldin A. Subsequently, cells were stained with CD4-phycoerythrin (PE) and IL-17-Alexa647 using intracellular flow to analyze the percent expression of IL-17 in CD4 + cells. Cytokine production from both CLL MSC and normal MSC as secreted into culture medium (CM) were tested using a commercial multiplex cytokine array (Invitrogen, CA). This array measures the level of 30 different cytokines. Results: Positively selected CD4+ cells from peripheral blood of normal donors contain minimal percentages of Th17 cells (range: 0.48–0.71%). IL-1β stimulation induced increased IL-17 expression (range: 1.05–1.12%). Co-culture of CLL MSC with CD4+ cells induced significantly increased IL-17 expression in the CD4+ T cells (range: 1.16–1.32%). The promoting effect of CLL MSC on these Th17 cells appeared to be mediated by direct contact since the CM of CLL MSC was not able to induce increased IL-17 expression (mean = 0.66%) to a similar level as direct co-culture. When IL-1b was used to stimulate Th17 cell differentiation from CD4+ cells, CLL MSC were able to further promote the level of Th17 cell differentiation (range: 2.01–2.63%), indicating synergistic function for CLL MSC with IL-1β. This latter finding again appeared to be more pronounced for CLL MSC as normal MSC with IL-1β was not able to promote Th17 cell differentiation to a similar degree. To further investigate the mechanism of CLL MSC on Th17 cell differentiation, we assessed the cytokine production for resting CLL MSC and normal MSC compared to cytokine production of CLL and normal MSC stimulated with IL-17. The data from multiplex cytokine arrays revealed that the cytokine profiles were not different between resting CLL and normal MSC; however, when MSC were stimulated with IL-17, there were significant differences between CLL and normal MSC in terms of IL-6 and MCP-1 production (IL-6, CLL vs. normal, 957.9 ± 98 vs. 554.2 ± 92.3 pg/ml, p = 0.01; MCP-1, CLL vs. normal, 787.7 ± 166.9 vs. 330.2 ± 116.5 pg/ml, p = 0.04, n = 7). Since both IL-6 and MCP-1 have been demonstrated to play important roles in Th17 differentiation, we are conducting further studies to dissect the mechanism of CLL MSC in the promotion of Th17 cell differentiation. Conclusions: These results indicate that MSC derived from CLL patients promotes Th17 cell differentiation in vitro, which is in contrast to the previous published suppressive role of normal MSC on Th17 cell differentiation. Recent findings have indeed demonstrated that CLL patients do have high percentage of Th17 cells (Cancer Res. 2009. 69: 5922) when compared to other lymphoproliferative diseases. Given this data we believe that CLL MSC are intrinsically different from normal MSC in terms of immune regulation and cytokine production. This may occur as a result of the bi-directional activation that we found to be present between MSC and CLL leukemic cells (Br. J Haematol. 2009. 147:471). In total, our findings demonstrated that the dynamic interactions between the CLL leukemic cells and MSC appear to influence the Th 17 cell levels. This is of biological and clinical interest in that Th17 cells have the potential to regulate the immune environment to favor tumor proliferation and progression. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 4610 Introduction Infections are a major cause of morbidity and mortality in patients with chronic lymphocytic leukemia (CLL). Up to 50% of CLL patients develop infectious complications, and 30–50% of all deaths in CLL patients are attributed to infections. Despite these data, the available research on infectious complications in CLL is primarily limited to patients participating in clinical trials of chemotherapy, obscuring the distinction between the risk of infection due to the disease’s natural history relative to the risk associated with therapy related immune suppression. METHODS: The Mayo Clinic Rochester (MCR), a tertiary referral center in rural southeastern Minnesota, is also the primary hematology center for southeastern Minnesota, northern Iowa, and western Wisconsin. There are no metropolitan areas or hematology specialty centers within a ∼50 mile radius. To explore the natural history of infection in a community-based cohort of CLL patients, we used the Mayo Clinic CLL database to identify all patients with newly diagnosed CLL who resided within 50 miles of MCR and diagnosed between January, 1999 and December, 2009. The comparison cohort consisted of 689 adult patients who also resided within 50 miles of MCR who were seen for a general medical examination between September, 2002 and December, 2009 and who were enrolled as controls in a case-control study of non-Hodgkin lymphoma. All hospitalizations at MCR among both cohorts were audited to document hospitalization with infection and cross-referenced with the Mayo Clinic infection database, which includes all culture results obtained from hospitalized MCR patients. Serologies and viral assays were also reviewed. Patients whose cultures were negative but who were given a clinical diagnosis of infection (e.g. pneumonia) and who were treated with a full course of antibiotic therapy were considered to have a culture negative infection. RESULTS: In May 2010, there were 2022 CLL patients in the Mayo Clinic CLL Database diagnosed between 1999 and 2009. Of these, 174 (9%) were local CLL patients residing within 50 miles of MCR. Median age at diagnosis for these non-referred CLL patients was 69 years (range 27–97). Most had early stage disease (60% stage 0; 32% stage I-II). On prognostic evaluation, 121 (75%) patients were CD38 negative, 66 (61%) ZAP-70 negative, 47 (50%) IGHV mutated, and 56 (62%) had either no abnormality or 13q14- as a sole abnormality on FISH analysis. 64 (37%) patients progressed to require treatment for CLL during follow-up. After median follow-up of 4.0 years (range 0–11), 32 (18.4%) CLL patients were hospitalized with infection at least once as compared to 20/689 (2.9%) individuals in the control cohort (odds ratio=7.5; p<0.0001) Figure 1A. Even prior to receiving treatment for CLL, the rate of hospitalization for infection remained higher than the control cohort (p=0.002; Figure 1B). The 32 CLL patients hospitalized with infection were admitted with infection a total of 89 times (median 1 hospitalization for infection per patient). A specific infectious organism was identified by cultures or serologies in 60 (63%) of the 89 infections in CLL cases and 10/27 (37%) infections among controls. Hospitalization for an opportunistic infection (e.g. cytomegalovirus, cryptococcus, filamentous fungi, mycobacteria, Pneumocystis) occurred in 5/174 (3%) CLL patients during follow-up compared to 0/689 controls (p<0.001). Finally, we performed a pooled multivariable analysis of all patients (n=863) to identify factors (age, sex, CLL diagnosis, CLL treatment) associated with infection risk. Most factors were independently associated with hospitalization for infection [Age (per year, OR=1.03, p=0.02), sex (male, OR=4.0, p<0.001), diagnosis of CLL (OR=2.1, p=0.09), and treatment for CLL (OR=5.9, p<0.001)]. In univariate analysis of CLL patients [sex (OR=4.2, p=0.01), higher Rai stage (p=0.046), unfavorable (del 17p13; del 11q23) FISH [OR=4.6, p=0.02] and unmutated IGHV [OR=2.8, p=0.07]) were associated with risk of infection. CONCLUSIONS: In this cohort study, patients with newly diagnosed CLL had a 7.5-fold risk of hospitalization for infection relative to the control cohort. After 4 year follow-up, ∼1 in 5 CLL patients required hospitalization for infection. Although CLL treatment was a substantial risk factor for infection, the risk of infection among untreated patients remained higher than controls. Disclosures: Kay: Biothera: Research Funding; Clegene: Research Funding; Cephalon: Research Funding; Genentech: Research Funding; Glaxo Smith Kline: Research Funding; Hospira: Research Funding; Novartis: Research Funding; Supergen: Research Funding; Calistoga: Membership on an entity’s Board of Directors or advisory committees; Celgene: Membership on an entity’s Board of Directors or advisory committees; Emergent Biosolutions (Formerly Trubion): Membership on an entity’s Board of Directors or advisory committees. Zent:GlaxoSmithKline: Research Funding; Genentech: Research Funding; Genzyme: Research Funding.

Abstract BACKGROUND: CD49d (a.k.a. alpha 4 integrin) plays a critical role in leukocyte trafficking, activation, survival, and facilitates interactions between leukocytes and stromal cells via VCAM-1 and fibronectin. We and others have previously reported that CD49d gene expression in CLL B-cells correlates with CD38 expression (Durig Blood101:2748; Pittner Leukemia19:2264). We have also confirmed CD49d protein expression correlates with CD38 protein expression on CLL B cells (Pittner Leukemia 19:2264). Notably, one small study reported that CD49d expression may relate to overall survival among CLL patients independent of CD38 status (Zucchetto, Leukemia 20:523), although the relationship to other prognostic markers, such as ZAP-70 and cytogenetic abnormalities, was not evaluated. METHODS: We measured CD49d expression by flow cytometry in 130 patients with CLL (NCI 1996 criteria), accrued to observational studies at Mayo Clinic, between 1994 – 2006. CD49d expression was measured by 2 color flow cytometry using antibodies specific for CD19 (BD Biosciences) and CD49d (BD Pharmingen). CD49d expression was compared to level of CD38 expression, ZAP-70 expression, and degree of IgVH gene mutation (all treated as continuous variables). We also evaluated the relationship between CD49d expression and time to treatment (TTT) and other prognostic parameters, using the previously published 30% threshold to classify CD49d expression (Zucchetto, Leukemia 20:523). Finally, we evaluated the relationship between CD49d expression and in vitro sensitivity to fludarabine (1 um x 24 hrs) and chlorambucil (1um x 24 hrs) in a subset of 70 patients. RESULTS: The percent of B-cells expressing CD49d varied from 0.3 to 99.4% among the 130 patients tested (median expression= 6.1). The level of CD49d strongly correlated with the expression of ZAP-70 (r=0.34; p<0.0001) and CD38 (r=0.65; p<0.0001), as well as the degree of IgVH gene mutation (r=−0.29; p=0.006). The relationship between CD49d expression and other prognostic parameters using the previously published 30% threshold to classify CD49d expression is shown in Table 1. The median time to treatment for patients with low CD49d expression was 14.9 years compared to 5.4 years for those with high CD49d expression (p=0.008) High CD49d expression was correlated with in vitro resistance to chlorambucil (r=0.27, p=0.03) but not fludarabine (r=0.20, p=0.09). CONCLUSION: CD49d expression varies on CLL B-cells and relates to other prognostic parameters and TTT as well as in vitro sensitivity to chlorambucil. Since CD49d facilitates interactions between CLL B-cells and stromal cells, the association of this marker with poor prognostic features and in vitro drug resistance may relate to enhanced stromal nuturing of leukemic cells with higher CD49d expression. Additional studies are needed to determine whether CD49d expression may be clinically useful as a prognostic test or to predict response to treatment in patients with CLL. CD49D low CD49D high P value % ZAP70+ 33.0 75.0 <0.0001 % IgVH unmutated 24.3 55.6 0.02 %CD38+ 12.8 63.9 <0.0001 FISH <0.0001 %with 17p- or 11q- or 6q− 9.2 25.0 % with +12 5.8 43.8 %with normal or 13q− 85.1 31.3 Current Stage 0.17 0 30.9 16.7 I-II 67.0 77.8 III-IV 2.1 5.6

Abstract Background Although its prevalence is not well defined, transformation to Hodgkin lymphoma (HL) is a rare but well recognized complication in patients with CLL. Prior studies have reported a median survival of 0.8-1.7 years in these patients. Prior therapy of CLL, especially with purine analogs, has been shown to have adverse impact on survival after development of HL. We used the Mayo Clinic CLL database to describe outcomes of CLL patients seen at our institution who developed HL. Methods The Mayo Clinic CLL database includes all consenting patients with a pathologic diagnosis of CLL. Patients who developed biopsy-proven HL were included in this analysis. For patients referred from an outside institution, pathology review at Mayo Clinic was mandatory to be included. Clinical characteristics, therapy and overall survival (OS) were analyzed for all HL patients. Results Among 3124 CLL patients seen at Mayo Clinic from 1/1995 to 7/2011, 26 developed HL. In a nested cohort of 1644 patients who were seen within 12 months of CLL diagnosis and followed prospectively, the prevalence of HL was 0.05%/year (10 year risk=0.5%). All 26 patients had classical HL. The median duration between CLL diagnosis and development of HL was 6.2 years (range, 0-24.5 years). The median age at diagnosis of HL was 68 years (range, 45-88 years) and 21 (81%) were male. At the time of HL diagnosis, the median WBC count was 7.8 x 109/L (range, 1.3-87.3), median hemoglobin was 11 gm/dL (range, 7.2-13), median platelet count was 220x109/L (range, 53-627), median serum lactate dehydrogenase was 249 U/L (range, 133-658), and median serum albumin was 3.4 gm/dL (range, 2.6-4.2). According to the Ann Arbor staging system for HL, 10 (38%) were Stage II, 2 (8%) were Stage III, 11 (42%) were Stage IV, and undetermined in 3 (12%) patients. Sixteen patients (61%) received HL therapy with doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD), seven (27%) received other chemotherapy, and treatment was unknown in 3 (12%) patients. No patient underwent stem cell transplantation as therapy for HL. After a median follow-up of 8.7 years from CLL diagnosis date, 16 (61%) patients have died. The median OS from date of HL diagnosis was 3.9 years (95% CI, 1.0 – 5.0 years). The International Prognostic score (IPS) for HL, originally proposed by Hasenclever in 1998, identified seven prognostic factors: serum albumin <4 gm/dL, hemoglobin <10.5 gm/dL, male sex, age >45 years, stage IV disease, WBC≥15 x 109/L, and lymphocytopenia in patients with newly diagnosed HL. When we applied these prognostic parameters (available in 22/26 patients, 85% in our cohort), the IPS score predicted median survival as follows: score of ≤2 (18% of the patients), median survival not reached; score of 3 (23% of the patients), 6.2 years; score of 4 (36% of the patients), 2.4 years; and score ≥5 (23% of the patients), 0.3 years (p-value=0.005, Figure 1). In contrast, the Richter syndrome prognostic score developed for CLL patients who transform to diffuse large B-cell lymphoma failed to predict survival in these patients (Tsimberidou, JCO, 2006). Of the 26 patients with HL, 16 (61%) had received therapy for their CLL prior to developing HL, including 12 (46%) who had received more than one line of therapy. Purine analogs had been administered for treatment of CLL prior to development of HL in 13/26 (50%) patients. The median survival of HL patients who had previously received CLL therapy was significantly worse compared to those who were untreated for CLL (2.8 years vs. 7.6 years, p-value=0.02). There was a trend toward shorter survival for HL patients who had received previous purine analog therapy for CLL compared to those who received alternate therapies (1.8 years vs. 5 years, p-value: p-value=0.07). Of the 9 HL biopsy samples in which Epstein Barr virus (EBV) in-situ hybridization studies were performed, EBV was detected in 6 (67%) patients. No association was observed between prior purine analog therapy and EBV status (p-value=1.0). There was no difference in survival according to the EBV status of HL (p-value=0.33). Conclusion The 10 year incidence of transformation to Hodgkin transformation among patients with newly diagnosed CLL is 0.5% (∼1/200 CLL patients). In this single-institution analysis, median survival of CLL patients who developed Hodgkin transformation of CLL was approximately 4 years after HL diagnosis. The IPS accurately predicted survival in our cohort of HL patients. Disclosures: Zent: Novartis: Research Funding; GlaxSmithKline: Research Funding; Biothera: Research Funding; Genzyme: Research Funding; Genentech : Research Funding. Shanafelt:Glaxo-Smith-Kline: Research Funding; Cephalon: Research Funding; Hospira: Research Funding; Celgene: Research Funding; Polyphenon E International: Research Funding; Genentech: Research Funding.