PIK3CA and pachyonychia congenita: In this study, we focus on five core pathways—TGF-Beta, RTK/RAS, WNT, PI3K, and TP53—selected based on their well-established biological relevance to PC pathogenesis and their high frequency of alteration reported in large-scale datasets, including The Cancer Genome Atlas (TCGA) [13] and other published genomic studies [14,15].