Button, Anna M.

8563 Background: Optimal initial treatment of follicular lymphoma (FL) is unknown. Rituximab as monotherapy (R) or as a component of immunochemotherapy (R+Chemo) is established as effective and it is now reasonable to re-examine the role of chemotherapy dosing. We explored clinical features, systemic treatment and chemotherapy delivery with comparative effectiveness of delivered dose intensity (DDI) on outcomes. Methods: We reviewed the University of Iowa/Mayo Clinic SPORE Molecular Epidemiology Resource database along with medical records on newly diagnosed grade I-IIIa FL who received systemic therapy from 2002 to 2009. Presenting clinicopathologic factors, outcomes and systemic therapy details including doses of chemotherapy were collected. The event-free (EFS) and overall survival (OS) effects of systemic therapy and chemotherapy DDI were analyzed with multivariate Cox regression. Confounding effects of FLIPI, grade, stage, and age were considered in the analysis. Results: From 2002 to 2009, 631 newly diagnosed FL were enrolled. Median follow up duration was 52.7 months. We identified 322 grade I-IIIa FL treated with systemic therapy including 93 R and 229 R+Chemo. Age and stage were similarly distributed between the R and R+Chemo groups; however, patients in the R group had lower grade (p<0.01) and FLIPI (p=0.03). Multivariate analysis showed no significant differences in EFS (HR=1.24, p=0.28) or OS (HR=0.55, p=0.13) for R compared to R+Chemo. Among R-CVP or R-CHOP treated FL, DDI data were collected for 73 doxorubicin (dox) and 137 cyclophosphamide (cyc) patients. Eighty-five percent of patients received 90% or more pre-planned DDI. After controlling for confounding factors, higher cycDDI was associated with improved EFS (HR 0.55, P=0.04) and OS (HR 0.74, P=0.03). No significant OS or EFS effects of doxDDI were observed. Conclusions: Addition of chemotherapy to rituximab was not associated with a detectable difference in survival outcomes in grade I-IIIa FL at a median follow-up of 52.7 months. Among R+Chemo treated FL, chemotherapy was delivered completely in most patients and more completed delivery of cyclophosphamide was associated with improved EFS and OS.

8061 Background: RCHOP is the standard first line therapy for DLBCL but elderly patients often receive suboptimal doses. Relative dose intensity (RDI) less than 70-90% has previously been associated with inferior survival in CHOP treated patients. We now investigate the clinical determinants of immunochemotherapy dose delivery and comparative effectiveness of dose intensity on lymphoma-specific outcomes in persons over the age of 60. Methods: SPORE MER (Molecular Epidemiology Resource) is a prospectively accrued observational study in which University of Iowa and Mayo Clinic patients with a diagnosis of Non Hodgkins lymphoma have been enrolled since 2003. We reviewed data from the Iowa patients along with medical records from DLBCL patients over the age of 60 treated with anthracycline based chemo immunotherapy consecutively enrolled up through to December 2009. Statistical tests of associations between RDI and clinicopathologic factors, as well as survival outcomes, were performed. Results: We identified 92 patients over the age of 60. The median age was 70. 47 subjects experienced at least 1 dose reduction, 26 subjects had dose delays, and 20 subjects were unable to complete therapy. RDI ranged from 0.30-1.70 (median 0.92) for doxorubicin and from 0.29-1.70 (median 0.97) for cyclophosphamide. 24 and 19% of subjects received < 80% of RDI for dox and cy respectively. Age (p< 0.001 for both dox and cy) and performance status (p=0.04 for dox) but not number of medications, ACE27 co-morbidity score, body surface area, nor need for acute care visits were associated with decreased RDI. Adjusted for IPI, RDI did NOT have a significant effect on event-free or lymphoma-specific survival. Conclusions: Among clinical variables, age is the dominant variable associated with delivery dose intensity for chemotherapy in elderly patients treated for DLBCL; and among elderly patients receiving chemo immunotherapy, we did not find an association between dose intensity and lymphoma-specific outcomes. [Table: see text]

Abstract The anti-CD20 monoclonal antibody rituximab (R) is widely used to treat B-cell malignancies including follicular lymphoma (FL). A better understanding of activity and resistance mechanisms is necessary for improving treatment outcomes. We previously reported that genetic variants in the complement pathway are associated with event-free survival of FL patients following R therapy. This correlation was particularly high for SNP rs3766404, located in intron 6 of Complement Factor H (CFH). Subjects with the minor allele of this SNP experienced inferior event-free survival. Five CFH related proteins (CFHR1-5) share a similar and sometimes overlapping function with CFH, including suppression of complement activation. Genetic variations within the CFH family locus are linked to a variety of complement-mediated disorders such as age-related macular degeneration (AMD) and atypical hemolytic uremic syndrome. Interestingly, AMD patients with the minor allele of rs3766404 frequently have deletion of CFHR3 and CFHR1, suggesting that loss of these proteins functionally impacts complement regulation. The current studies were designed to better understand the relationship between R therapy of FL and CFH family proteins. CFH and CFHR1 protein levels were quantified in serum samples from both normal subjects (n=59) and FL (n=108) subjects from the Iowa/Mayo Lymphoma SPORE Molecular Epidemiology Resource. No correlation was observed between the quantity of CFH in serum and SNP genotype in either cohort. However, in both cohorts, individuals homozygous for the minor allele in SNP rs3766404 lacked detectable expression of CFHR1. Homozygotes for the major allele expressed the highest levels of CFHR1, and heterozygotes expressed intermediate levels. Among FL subjects treated with R as a component of initial therapy, increased levels of CFHR1 were associated with improved event-free survival (hazard ratio 0.48, 95% confidence interval 0.28-0.82, p=0.0051). In contrast, CFHR1 levels had no impact on outcome among the FL subjects who did not receive R as a component of initial therapy. This subset of FL subjects included those observed off therapy. The effect of CFHR1 levels on outcome for those subjects treated with R versus those not treated with R was statistically different (p=0.0023 based on a Cox proportional hazard model). There was no correlation between CFH levels and outcome in any population. CFHR1 binds the complement component C3b, inhibiting downstream complement activation. We previously demonstrated that complement can inhibit R activity in vitro. Specifically, C3b deposition can have a negative impact on antibody–mediated tumor cell killing by interfering with R-induced NK cell activation and antibody dependent cellular cytotoxicity. Our current finding that higher CFHR1 correlates with improved outcome following R therapy provides further evidence that the effect of complement on therapeutic monoclonal antibodies is complex. These findings may have implications for predicting response to, and optimization of, anti-CD20 and other antibody therapies. Ongoing studies are exploring this possibility in additional patient cohorts, the potential role of other CFH family members, and the underlying biology associated with these observations. Disclosures: Link: Genentech: Consultancy; Millenium: Consultancy; Pharmacyclics: Consultancy; Spectrum: Consultancy; Genentech: Research Funding; Millenium: Research Funding; Pharacyclics: Research Funding.