Diagnostic and Therapeutic Challenges Related to HER2 Heterogeneity in Gastric Cancer: Bridging Molecular Pathology and Clinical Decision-Making. - Rosanu, Nelia Marina; Gervaso, Lorenzo; Lobrano, Renato; Vanoli, Alessandro; Cella, Chiara Alessandra; Fusco, Nicola; Fazio, Nicola (International Journal of Molecular Sciences, 2026)