SMAD4 and metastatic malignant neoplasm in the lymph nodes: Integrating preoperative 18F-PET/CT radiomic features, changes in a sensitive biomarker (ΔCA19-9), pathological characteristics (tumor differentiation, lymph node metastasis, LVI, and SMAD4 expression), and the duration of adjuvant chemotherapy associated with early recurrence, the patients were scored ranging from 0 to 40.