s with other cancers, the pro- cess of the transformation
of normal melanocytes into ma- lignant melanoma requires the acquisition of genomic abnormal-
ities. Although progress in the search for the targets of genetic aberration in cancer has been
stunning in many respects, the clinical effect of this work has been limited. But it is clear that
tracking down the genetic chang- es in cancer is no mere academic exercise; rather, it has proved
to be a powerful approach to the selection of therapeutic targets. Progress in the treatment of
chronic myelogenous leukemia, gastrointestinal stromal tumor, and some lung cancers can be di-
rectly linked to the development of therapies that target specific pathways activated by acquired
somatic mutations. The pursuit of genetic abnormalities in can-