Furthermore, analysis of PTEN protein expression by IHC has the added advantage of detecting PTEN loss that is not caused by a genomic alteration (such as miRNA and epigenetic silencing) and which is often missed by FISH analysis, especially in the context of PTEN loss of heterozygosity (LOH), which is present in 15–49% and up to 50% of localized and metastatic prostate cancers, respectively [23,63]. The gene discussed is PTEN; the disease is metastatic prostate carcinoma.