Three Novel Rare TP53 Fusion Mutations in a Patient with Multiple Primary Cancers: a Case Report

As survival rates improve and detection technologies advance, the occurrence of multiple primary cancers (MPCs) has been increasing. Approximately 16％of cancer survivors develop a subsequent malignancy, with lung cancer often developing after esophageal cancer due to potential"field cancerization"effects. Despite this observation, the genetic heterogeneity underlying MPCs remains understudied. However, the recent emergence of genetic testing has expanded the scope of investigations into MPCs to investigate signatures underlying cancer predisposition. This report reveals 3 unprecedented TP53 fusion mutations in a Chinese patient afflicted by MPCs, namely, AP1M2-TP53 (A1;T11) fusion, TP53-ILF3 (T10;I13) fusion, and SLC44A2-TP53 (S5;T11) fusion. This patient exhibited an extended period of survival after diagnosis of extensive-stage small cell lung cancer, which occurred 6 years after the diagnosis of esophageal squamous cell cancer. This unique report may provide supplementary data that enhance our understanding of the genetic landscape of MPCs.