Blood transfusion history and risk of non-Hodgkin lymphoma: an InterLymph pooled analysis.

PURPOSE: To conduct a pooled analysis assessing the association of blood transfusion with risk of non-Hodgkin lymphoma (NHL). METHODS: We used harmonized data from 13 case-control studies (10,805 cases, 14,026 controls) in the InterLymph Consortium. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression, adjusted for study design variables. RESULTS: Among non-Hispanic whites (NHW), history of any transfusion was inversely associated with NHL risk for men (OR 0.74; 95% CI 0.65-0.83) but not women (OR 0.92; 95% CI 0.83-1.03), pheterogeneity = 0.014. Transfusion history was not associated with risk in other racial/ethnic groups. There was no trend with the number of transfusions, time since first transfusion, age at first transfusion, or decade of first transfusion, and further adjustment for socioeconomic status, body mass index, smoking, alcohol use, and HCV seropositivity did not alter the results. Associations for NHW men were stronger in hospital-based (OR 0.56; 95% CI 0.45-0.70) but still apparent in population-based (OR 0.84; 95% CI 0.72-0.98) studies. CONCLUSIONS: In the setting of a literature reporting mainly null and some positive associations, and the lack of a clear methodologic explanation for our inverse association restricted to NHW men, the current body of evidence suggests that there is no association of blood transfusion with risk of NHL.

Loss of MHC class II gene and protein expression in diffuse large B-cell lymphoma is related to decreased tumor immunosurveillance and poor patient survival regardless of other prognostic factors: a follow-up study from the Leukemia and Lymphoma Molecular Profiling Project.

The Leukemia and Lymphoma Molecular Profiling Project recently published results from DNA microarray analyses of 240 diffuse large B-cell lymphomas (DLBCLs). Four gene expression "signatures" were identified as correlated with patient outcome, including the major histocompatibility complex (MHC) class II genes (eg, HLA-DRA) which correlated with better survival. We further analyzed the effects of HLA-DRA on survival and correlated gene expression with protein status and tumor-infiltrating lymphocytes. The 5-year overall survival was 24% in the lowest 10% of HLA-DRA expression, 37% in the 10% to 25% group, 50% in the 25% to 50% group, and 55% for patients in the highest 50%. Further analysis demonstrated that the hazard ratio of death was a nonlinear function of HLA-DRA expression. Adjustment for the International Prognostic Index did not alter the impact of HLA-DRA on survival. Other MHC class II genes were found to predict survival similarly. Microarray HLA-DRA expression correlated with the presence or absence of human leukocyte antigen-DR (HLA-DR) protein in 20 of 22 cases assessed. Fewer tumor-infiltrating CD8(+) T cells were detected in MHC class II-negative cases compared with positive cases (2.8% versus 11.0%; P =.001), supporting the hypothesis that loss of tumor immunosurveillance has a devastating effect on patient outcome in DLBCL.