【Abstract】Objective To investigate the expression of extracellular matrix metalloproteinase inducer(EMMPRIN),matrix metalloproteinase-1(MMP1),MMP9,tissue inhibitors of metalloproteinase-1(TIMP1) and the mast cell count (MCC) and to detect their clinicopathologic significance and relationship in pancreatic cancer tissues. Methods Immunohistochemical method of avidin-biotin complex was used for those 5 targets on the routinely paraffinembedded sections of surgical resected specimen of 51 cases with pancreatic carcinoma. Results The positive rates of EMMPRIN,MMP1,MMP9 and TIMP1 were 56.9%,54.9%,60.8% and 49.0% and its scoring were 2.5±1.5,2.3±1.9,2.4±1.6 and 1.9±1.6 respectively. The mean of MCC was (16.1±6.8)/HP in total cases. The positive rates or scorings of EMMPRIN,MMP1,MMP9 and MCC were significantly lower in high differentiated or without-metastatic cases than in low differentiated or with-metastatic ones(P<0.05 or P<0.01), and those targets (except MCC and scoring of MMP9) of middle differentiated ones were lower than those of low differentiated while that of TIMP1 was opposite(P<0.01). The MCC showed significantly higher in the positive cases of EMMPRIN, MMP1 and MMP9 or negative cases of TIMP1 than in the negative ones of EMMPRIN, MMP1 and MMP9 or positive ones of TIMP1. The closely positive correlations were found among the MCC and the scoring of EMMPRIN, MMP1 and MMP9. The closely negative correlations existed among the scoring of TIMP1 and the other four targets.Conclusion The MCC and the expressions of EMMPRIN, MMP1, MMP9 and TIMP1 might be important biological markers for reflecting the progression and the prognosis of pancreatic carcinoma. They might have co-regulated effects on the potentials of invasion and metastasis of pancreatic carcinoma or other malignant lesions.