Recent Update in Pathologic Diagnosis for Pancreatic Cystic Neoplasm

Jang, Kee Taek

Abstract

Pancreas cystic neoplasm is a relatively common disease. However, its' pathologic diagnosis is not easy. The most frequent problem is low cellularity when compared to another organ cytology or biopsy material. Considering the procedure and anatomic difficulty, it is not uncommon to observe a low cellular smear or scanty volume of cells in the biopsy specimen. In this case, the molecular pathology test, including next-generation sequencing, may be helpful. If pathologist can identify some mutation in cells or cystic fluid, differential diagnosis of cystic neoplasm may be possible. These are KRAS and GNAS, VHL, and CTNNB1 mutation in mucinous cystic neoplasm, intraductal papillary-mucinous neoplasm, serous cystic neoplasm, and solid pseudopapillary neoplasm, respectively. The next-generation sequencing is an emerging molecular test that can detect multiple biomarkers for diagnosis, including pancreas cystic neoplasm. It has been reported that next-generation sequencing test can be applied for differential diagnosis of pancreas cystic neoplasm. However, these molecular pathology tests were not all-around; it needs to be properly managed with pathologist's quality control. It should be remembered that even if it goes through quality control, it may show a failure rate of around 30%. Despite the advances in molecular methods of high techniques, it should be remembered that the most important thing in pathologic diagnosis of pancreas cystic neoplasm is an endoscopist's skill and pathologist's expertise those provide adequate specimen and accurate diagnosis.