SMAD4 and neoplasm: Nevertheless, we confirmed the presence of mutations commonly detected in T1−T3, i.e., PIK3CA (E545K), KRAS (G12D), and SMAD4 (R361C and R361H), by Sanger sequencing of tumor samples from the first recurrence, indicating that this tumor also recurred from T1 and shares the trunk mutational characteristics with T2 and T3 (Supplementary Figure 3).