Classification and pathology features of pancreatic cystic neoplasmas        LU Zhao-hui,CHEN Jie. Department of Pathology, Peking Union Medical College Hospital , Peking Union Medical College, Chinese Academy of Medical Science,Beijing100730,China
Corresponding author: CHEN Jie,E-mail:xhblk@163.com
Abstract    Serous cystadenoma consists of oligocyst, multiple microcysts or solid acinars lined by a glycogen-rich cuboidal epithelium. Based on the low risk of malignancy of SCA, surgical resection should only be considered when the cysts are causing symptoms or when differentiation from a mucinous cystic neoplasm with concerning features is not possible. Mucinous cystic neoplasm and Intraductal papillary mucinous neoplasm can all be classified into 4 catograies: low-grade dysplasia, moderate dysplasia, high-grade dysplasia and with invasive carcinoma, while the major difference between them is whether the cysts are communicated to the duct of pancreas and most MCNs develop ovarian-like stroma. Solid-pseudopapillary tumor of pancreas is a neoplasm with distinctive morphology and immunophenotype, most of them are benign although labeled with low malignancies. Most acinar cell cystadenomas are benign, just like the serous cystadenoma, only very rare cases reported to be malignant. Other miscellaneous cystic tumors consist mature teratoma, lymphoepithelial cyst, cystic lymphangioma and Multicystic adenomatoid pancreatic hamartoma, all follow a benign course. Attentions should be paid to some primary solid pancreatic tumors with cystic transformation, which might be confused with some primary cystic neoplasms.