pancreatic acinar cystic transformation

Definition : Acinar cell cystadenoma (ACA) of the pancreas was initially described as a non-neoplastic cyst of the pancreas and, at that time, referred to as "acinar cystic transformation." In subsequent studies, these lesions were given the designation of "-oma," despite the relative lack of evidence supporting a neoplastic process.

Early lesions are marked by acinar dilatation that expands into and incorporates smaller ductules and later larger ducts. As the cysts increase in size, they fuse forming larger cysts. Later lesions demonstrate a unilocular cyst lined by predominantly acinar epithelium with scattered ductal cells.

The term cystadenoma, with its neoplastic connotation, does not seem to accurately reflect the histologic, immunohistochemical, or molecular features of these lesions.

It has been suggested to readopt the term "acinar cystic transformation" until the non-neoplastic versus neoplastic origin of these lesions can be resolved. (24076773)

Reference

 Acinar cell cystadenoma of the pancreas: a benign neoplasm or non-neoplastic ballooning of acinar and ductal epithelium? Singhi AD, Norwood S, Liu TC, Sharma R, Wolfgang CL, Schulick RD, Zeh HJ, Hruban RH. Am J Surg Pathol. 2013 Sep;37(9):1329-35. doi : 10.1097/PAS.0b013e3182a1ad72 PMID: 24076773