ABSTRACT
Objective To investigate the relationship between the expression of Pin1 and Ki67 and the clinicopathologic features of gastrointestinal stromal tumors (GIST).Methods 40 paraffin-embeded specimens of surgical resected GIST from Jan.2013 to May.2015 in Pathology Department of Yuhuangding Hospital Affiliated to Qingdao University were retrieved and expressions of Pin1 and Ki67 were detected by immunohistochemical methods.Results The positivity rate of Pin1 and Ki67 in GIST was 80％ and 32.5％ respectively.The expression of Pin1 was associated with malignancy of GIST,tumor location,tumor size and mitotic counts.The expression of Ki67 is associated with malignancy of GIST,tumor location,tumor size,mitotic counts and tumour necrosis.Pin1 expression was positively related with Ki67 expression.Conclusion Pin1 and Ki67 is closely related with malignancy of GIST,which may be potential factors in predicting prognosis of GIST.