Previous evidence of PTEN loss in early pre-cancer lesions in the fallopian tubes,25 its role in the mouse models of HGSOC12–14 and high focal prevalence of PTEN loss compared to other neighbouring genes (Gistic p value for the likelihood of PTEN loss being a driver: 7.3e−17)11,32 in HGSOC are supportive of the role of PTEN loss in driving progression in HGSOC. This evidence concerns the gene PTEN and cancer.