Abstract： Objective To explore the the prognostic significance of MMP-9,uPA and uPAR protein expression and its relationship with clinical-pathologic factors in esophageal squamous cell carcinoma treated by radiotherapy.Methods MMP-9,uPA and uPAR protein expression was measured in 59 esophageal car cinomas and 41 peri-carcinoma tissues with immunohistochemistry.The relationship between the protein expression and the clinical-pathological parameters was analyzed,and the prognostic factors in esophageal squamous cell carcinoma treated by radiotherapy alone was evaluated.Results The rates of positive expression of MMP-9.uPA and uPAR were 85%,76%and 78%in esophageal carcinoma and 39%,49%and 44%in peri-carcinoma tissues(x2=22.54,8.04 and 12.18;P=0.000,0.005 and 0.000).The rates of positive expression of MMP-9 was 79%and 100%when the depth of tumor invasion was≤2 am and＞2 cm(P=0.048),respectively.The expression of uPA was significantly correlated with the status of fat interspace between the esophageal lesion and the vertebra in CT seaning image.When the fat interspace existed and disappeared,the rates of strong positive expression was 44%and 70%,respectively(χ2=4.21,P=0.040).The positive expression rate of uPA was significantly correlated with distant metastasis.which was 100%in patients with distant metastasis and 68.89%in those without distant metastasis(χ2=4.12,P=0.042).r11}lepositive expression rate of MMP-9.uPA and uPAR did not affect the prognosis and the short-term result of esoph.ageal carcinoma treated by radiotherapy alone.Conclusions The protein expression of MMP-9,uPA and uPAR may correlate with local infiltration and distant metastasis in esophageal squamous cell carcinoma.Protein expression may not influence the prognosis of esophageal carcinoma treated by radio therapy,though long time followed-up is stil needed.