Sulindac is a non-steroidal anti-inflammatory drug (NSAID) that has shown to be effective in preventing intestinal tumors in familial adenomatosis polyposis patients that inherit a mutant allele of the adenomatosis polyposis coli (APC) gene [1,2], in inhibiting tumor formation in mouse genetic models (ApcMin and Apc1638N+) in which an allele of the homologous mouse Apc gene is inactivated by a mutation [3-5], and in inhibiting carcinogen-induced colon tumor formation in rats [6]. This evidence concerns the gene APC and intestinal neoplasm.