ABSTRACT
Objective To investigate the clinicopathological features of undifferentiated pancreatic carcinoma with osteoclast-like giant cells (UOC).Methods Clinical and pathological data of 6 patients with UOC admitted in Navy Medical University affiliated Changhai Hospital from April 2011 to December 2017 were retrospectively analyzed.The expressions of Cam5.2,EMA,CD68,vimentin,lysozyme,E-cad,C-erbB-2,p53,MUC1,MLH1,MSH2,MSH6,Osteoponin and Ki-67 were detected by immunohistochemistry,and Kras gene mutations was measured by fluorescence quantitative PCR method.Results There were two main types of UOC cells.One type was oval or spindle mononuclear tumor cells,and the other was osteoclast-like giant cells scattered among mononuclear cells.Immunohistochemical staining results showed that the epithelial markers like CAM5.2,EMA,E-cad,MLH1,MSH2,MSH6 and Ki-67 of the components of ductal adenocarcinoma in 6 UOC patients were all positively expressed,and the mesenchymal markers like vimentin,CD68,lysozyme and tumor-related markers like Her-2,p53 and MUC1 were all negatively expressed.Vimentin,CD68,lysozyme and Osteoponin were positively expressed in osteoclast-like giant cells,but epithelial markers like Cam5.2,EMA,E-cad,MLH1,MSH2 and MSH6 were negatively expressed.6 UOC patients all had K-ras codon 12 mutation,and the mutant type was GGT ＞ TGT,GGT ＞ GTT,GGT ＞ GCT,and no codon 13 mutation was observed.Conclusions Osteoclast-like giant cells may be reactive multinucleated giant cells rather than neoplastic components.