“…Compared with the hypothesis-driven candidate gene approach, which has been the preferred method ology in previous pharmacogenetic analy-ses [9][10][11][12]16], the agnostic genome-wide association study strategy would be tremendously helpful for elucidating the complete pharmaco genetic reper toire of capecitabine-related toxicities. A prospective genomewide association study of breast cancer patients treated with single-agent capecitabine from Singapore will soon be reported [20] and will reveal the extent to which common and rare variation modulates the risk of hand-foot syndrome, a common disfiguring dermato logic toxic reaction to capecitabine. Another area for consideration in future and ongoing studies is to prioritize patients who received capecitabine monotherapy (as opposed to capecitabine-containing combination regimens or who received other fluoropyrimidine drugs), as this would allow more accurate delineation of the pharmaco genetic associations with capecitabine toxicity.…”