PRECISE MICRODISSECTION OF HUMAN PROSTATE CANCERS REVEALS GENOTYPIC HETEROGENEITY

To determine the incidence of genetic heterogeneity in primary prostat e cancer, we have microdissected 125 tumor and mesenchymal foci from I S patient biopsies and analyzed the DNA for loss of heterozygosity usi ng PCR microsatellite markers, In 100% of patients with genetic lesion s on chromosome 8p, there was evidence for intra-tumoral genetic heter ogeneity. There was also a low but significant incidence of loss of he terozygosity in mesenchymal tissue, Our results show that phenotypical ly similar tumor foci can have different genotypes and provide evidenc e for the multifocality of tumor development in the prostate.