Abstract 1823: The association between cigarette smoking and lymphoid neoplasms in a large US cohort study

Abstract

Abstract Few modifiable risk factors for lymphoid neoplasms have been identified. Cigarette smoking has been hypothesized to influence risk through direct carcinogenic effects, immunosuppression, and increased leukocyte production. However, prior studies of cigarette smoking and lymphoid neoplasms have been notably inconsistent. Often, this is attributed to the heterogeneous nature of the disease. Among the few studies that examined this association across lymphoma subtypes, some showed positive associations with follicular lymphoma and with Hodgkin disease. To further clarify these relationships, we examined cigarette smoking status, intensity, and duration in relation to the risk of non-Hodgkin lymphomas (NHL), subtypes of NHL (diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), and chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), multiple myeloma (MM), and T-cell lymphomas), and Hodgkin disease in the American Cancer Society Cancer Prevention Study II (CPS-II) Nutrition Cohort, a prospective study of cancer incidence and mortality in US men and women. From 1992-2007, 2,034 incident NHL cases and 57 Hodgkin cases were identified among 152,989 men and women who were cancer-free at enrollment. Cox proportional hazards modeling was used to compute hazard rate ratios (RR) while adjusting for potential confounders. When compared with never smokers there was an association with NHL among former smokers (RR=1.13, 95% CI (1.03-1.24)), but not current smokers (RR=1.03, 95% CI (0.86-1.23)), and not with smoking intensity or duration. Among NHL sub-types, ever smoking was significantly associated with CLL/SLL (RR=1.37) and T-cell lymphomas (RR=1.55). No association was seen with other sub-types of NHL, or Hodgkin disease. When associations with NHL were examined by gender there were significant differences in men and women by current smoking status (interaction p=0.015). A strong dose response relationship with the number of years smoked was noted in current female smokers (p-trend=0.005) resulting in a 2-fold higher risk of NHL among women smoking for 50 years or more compared with never smokers (RR=2.27, 95% CI 1.32-3.89). Associations also differed by gender for some subgroups of NHL. Specifically, current smoking was significantly associated with CLL/SLL and FL in women, but associations were null or inverse in men. However, T-cell lymphomas were associated with similarly increased risk in both men and women. In conclusion, this study supports an association of cigarette smoking with T-cell lymphomas, and associations with smoking among women especially for the CLL/SLL and follicular sub-types. It also provides further evidence that the etiology of lymphoid neoplasms may vary by lymphoma sub-type and gender, and that studies of these neoplasms should carefully consider this disease heterogeneity. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1823.