SMAD4 and metastatic malignant neoplasm in the lymph nodes: Variables with P <0.05 in the univariate analysis were further incorporated into multivariable Cox analysis including the following factors: rad-score (high vs low), tumor differentiation (low vs moderate-high), lymph node metastasis (positive vs negative), ΔCA19-9 (<80% decrease vs ≥80% decrease), LVI (positive vs negative), SMAD4 expression (negative vs positive) and duration of adjuvant therapy (<two vs two to four vs four to six cycles).