Several hundreds of thousand of patients with various inflammatory types of arthritis have not taken one or more of the anti-TNF drugs (humira, enbrel, remicade). We feel fairly certain based on all of these data that these drugs do not increase the risk of most tumors like breast, colon, prostate, stomach, kidney. However, there is a lingering concern that they could increase the risk for lymph node cancers (lymphomas) but this is debatable because at least one type of inflammatory arthritis (rheumatoid arthritis) itself causes increased risk of lymphoma. So, it might be the disease not the drug. There have also been reports that these agents could possibly increase risk for skin cancers, but this isn’t definitive yet either. Each patient has to weigh the potential destructiveness of the arthritis against the relatively small chance that the drug might increase risk of a cancer.