TP53 and neoplasm: In a retrospective study involving 159 patients, positive TP53 mutation status (but not P53 overexpression) was the lone risk factor with respect to MT (P < .03).50 In a further study with 36 patients, TP53 was strongly and statistically associated with MT (P = .0344), specifically, 9 of 14 tumors (75%) harbouring TP53 mutations showed MT within 12 ± 75 months (median 37 months), compared to 9/22 tumors (41%) wild type TP53 tumours.51 Only 1p/19q co-deletion had a positive prognostic effect on MT.18,20,54