Fig. 1.

Examples of FISH findings using the PTEN deletion probe. a Normal PTEN copy numbers as indicated by two orange PTEN signals and two green centromere 10 signals. b Heterozygous deletion as indicated by the lack of one orange PTEN signal and two green centromere 10 signals. c Homozygous deletion as indicated by the complete absence of orange PTEN signals and the presents of two centromere 10 signals in all tumor cells