SMAD4 and neoplasm: However, no significant relationship was found between Smad4 staining and clinical parameters in pancreatic cancer, including tumor differentiation (OR = 0.90, 95%CI: 0.48–1.68; Pheterogeneity = 0.597), lymph node metastasis (OR = 0.40, 95%CI: 0.09–1.81; Pheterogeneity<0.001) or tumor size (OR = 1.21, 95%CI: 0.83–1.78; Pheterogeneity = 0.458).