Abstract 3453: Medical history, lifestyle, and family history exposures and chronic lymphocytic leukemia outcome

Background: Associations of medical history, lifestyle, and family history of hematological disorders with risk of chronic lymphocytic leukemia (CLL) have been previously established (1), but these exposures have not been well-studied as contributing factors to CLL prognosis. Here we investigate the association of these exposures with time to first treatment (TTFT) in 730 CLL patients. Methods: Newly diagnosed CLL patients seen at the Mayo Clinic between 2002 and 2012 were enrolled. CLL was defined according to the 1996 NCI-Working Group criteria (2). Risk factor data (including body mass index, smoking, alcohol use, sun exposure, having lived on a farm, any allergy, asthma, eczema, blood transfusion, diabetes, rheumatoid arthritis, and family history of hematological malignancy) were collected from self-administered questionnaires. Clinical and prognostic characteristics for CLL were extracted from medical records. Analyses were performed using Cox regression with first treatment as the event. Hazard ratios (HR) and 95% confidence intervals were estimated. We used Bonferroni correction for multiple testing with statistical significance at 0.004. Results: The median age at CLL diagnosis was 63 years (range 36 - 89); 65% were male, and 95% had a Rai stage< III. The median follow up time was 6.3 years, and 40% received treatment. In unadjusted analyses, patients with any history of allergies had significantly longer TTFT (HR = 0.66, 95% CI: 0.51-0.85, P = 0.001). We also observed borderline significance with history of asthma (HR = 0.53, 95% CI: 0.34-0.85, P = 0.008). These associations held after adjusting for important prognostic factors including age, sex, Rai stage, and IGVH mutational status. The other risk factors had non-significant associations (P>0.1). Conclusions: We observed an improved CLL prognosis in patients with a history of any allergies or asthma. These results were independent of other prognostic markers and suggest that an overactive IgE level from environmental exposures may provide insight into the progression of CLL. Literature Cited 1. Slager SL, Benavente Y, Blair A, Vermeulen R, Cerhan JR, Costantini AS, et al. Medical history, lifestyle, family history, and occupational risk factors for chronic lymphocytic leukemia/small lymphocytic lymphoma: the InterLymph Non-Hodgkin Lymphoma Subtypes Project. J Natl Cancer Inst Monogr. 2014 Aug;2014(48):41-51. 2. Cheson BD, Bennett JM, Grever M, Kay N, Keating MJ, O’Brien S, et al. National Canc