PTEN and neoplasm: For example, BRCA1 mutation carriers appear to predispose to serous ovarian cancers (Pal et al, 2005); mutations in the PTEN tumour suppressor gene are more associated with endometrioid ovarian cancers (Obata et al, 1998); and K-ras mutations are more common in mucinous tumours than in either serous of endometrioid subtypes (Gemignani et al, 2003).