How strong is the association between smoking and colorectal cancer?

摘要

Earlier this year the International Agency for Research on Cancer published an extensive re-examination of human carcinogens including tobacco [1]. For the first time the International Agency for Research on Cancer listed the colorectum among the cancer sites for which there is sufficient evidence of a causal association with tobacco. This evaluation was mainly based on the publication of four meta-analyses, which consistently showed a significant association between cigarette smoking and colorectal cancer (CRC) [2-5].