FGFR4 and neoplasm: The primary tumor was sequenced using the TSO500 panel on FFPE tissue, capturing a moderately altered molecular landscape, characterized by canonical CRC drivers such as TP53 (p.E286K) and additional mutations of uncertain or emerging relevance, including in BRCA2, FGFR4, MSH6, and RAD50. This initial profile, with a TMB of 7.1 mutations per megabase and confirmed MSS, suggested a genomically stable phenotype consistent with conventional colorectal adenocarcinoma (Hecht et al., 2023; San-Román-Gil et al., 2023).