PTEN and neoplasm: Mice bearing the triple-deleted Trp53−/−;Brca2−/−;Pten−/− tumours survived 99 days, which was significantly more than Trp53−/− (p < 0.0001; Table 2) but less than Trp53−/−;Brca2−/−, although this latter comparison did not reach statistical significance (p = 0.078).