Cox-2 and cancer chemoprevention: picking up the pieces.

Inhibitors of prostaglandin synthesis show great promise as cancer chemopreventive agents, with efficacy demonstrated in randomized clinical trials. Unfortunately, these agents also cause toxicity in susceptible individuals. The recent reports of cardiovascular adverse events in patients treated with selective Cox-2 inhibitors for colorectal adenoma prevention remind us that all therapies carry risks as well as benefits. This article will discuss the biologic rationale for using selective Cox-2 inhibitors in cancer chemoprevention, and outline new avenues of research necessary to allow their successful use in patients at risk for colorectal cancer.