A Case of Lung Squamous Cell Carcinoma Harboring TP53 Mutation and PLPP5‐FGFR1 Fusion Gene

Lung squamous cell carcinoma (LUSC) is one of the most common subtype of lung cancer and is associated with the poor prognoses. The fibroblast growth factor receptor (FGFR) family is known to be activated through fusions with various partners across multiple cancer types, including nonsmall cell lung cancer (NSCLC). FGFR inhibitors are currently undergoing clinical evaluation for the treatment of tumors harboring these fusions. While FGFR1 amplification has been well-documented in numerous NSCLC datasets, the characterization of specific FGFR fusion variants remains limited. In this study, we identified a novel PLPP5-FGFR1 fusion in a 65-year-old male patient with lung squamous cell carcinoma through targeted RNA sequencing. The fusion junction was located between exon 1 of PLPP5 and exon 5 of FGFR1, and the result was validated by Sanger sequencing. To our knowledge, this is the first reported case of a PLPP5-FGFR1 fusion coexisting with a TP53 mutation in LUSC. These findings broaden the spectrum of potential translocation partners in FGFR1 fusions, and the clinical implications of this novel fusion on treatment outcomes and prognosis warrant further investigation and long-term follow-up.