TP53 and neoplasm: The prevalence of p53 mutation increased from 4.6% for the noninvasive low-grade tumours to 19.4% for the noninvasive high-grade tumours (POR=4.4; 95% CI=1.5–12.5) and to 15.4% for invasive tumours (POR=3.4; 95% CI=1.4–8.0).