TP53 and mucinous adenocarcinoma: The 7 lesions of non‐appendiceal origin generally showed a similar mutational landscape to the appendiceal lesions, with GNAS and KRAS variants the most frequent, although one patient had no mutation in either gene but did harbour multihit mutation of TP53; this lesion was a mucinous adenocarcinoma of the urachus (Figure 1A).