Risk of chemotherapy-induced pulmonary fibrosis is associated with polymorphic tumour necrosis factor-a2 gene

In some patients, chemotherapy (CHT) of cancer can result in pulmonary inflammation and fibrosis, eventually leading to respiratory insufficiency. As animal studies have underlined the importance of major histocompatibility complex (MHC) genes in the susceptibility to bleomycin (BLM)-induced pulmonary fibrosis, the authors typed human leukocyte antigen-DR (HLA-DR) and tumor necrosis factor (TNF) genes in patients treated for Hodgkin's disease by a therapy including bleomycin. Patients were divided into pulmonary responders (PR) (n=21) or nonresponders (PNR) (n=20) on the basis of pulmonary alterations detected on chest radiography and the cumulated amount of BLM injected. The incidence of TNFa2, a microsatellite allele in the promoter region of the TNFB gene reported to be associated with increased TNF-a production, was significantly higher in PR than PNR (65% versus 19%). HLA-DRB1*15 showed a weak but nonsignificant association with the PR phenotype (50% versus 14%), as well as HLA-DRB1*03 (30% versus 19%) and TNFA-308*2 (30% versus 14%). TNFa2 and DR15 were independent risk factors and the occurrence of either genetic marker was 85% versus 29% in the PR and PNR groups respectively. Thus, the polymorphic TNFa2 microsatellite is associated with a risk of chemotherapy-induced pulmonary fibrosis.