PIK3CA and neoplasm: High PDC grade (P = 0.0112), the presence of tumor budding (P = 0.0334), LVI (P < 0.0001), KRAS mutations (P = 0.0228), PIK3CA mutations (P = 0.0214), multiple genetic mutations in KRAS and PIK3CA genes (P = 0.039), and nodal micrometastases (P < 0.0001) were significant prognostic variables for CSS.