NTRK1 and neoplasm: Targeted NGS sequencing revealed shared frameshift mutations in TP53 c.[835delG] and three other pathogenic missense mutations, JAK1 c.[383G>A], MAPK8IP1 c.[1484C>A] and NTRK1 c.[1925C>T], in both P1-S1 and P1-S2, indicating that the tumor sample from the second surgery (recurrent tumor) was derived from the residual tissue from the first tumor.