In summary, this meta-analysis of clinical trial data indicates
that aspirin reduces the risk of recurrence of colorectal adenomas.
This effect emerged rather quickly after the initiation of aspirin
use, seemed more marked for advanced lesions than for adenomas
overall, and was seen in essentially all subgroups examined. Our
fi ndings suggest that aspirin interferes with colorectal carcinogenesis
relatively early in the progression from normal mucosa to
adenoma or advanced lesion