Clinicopathological features of intraductal papillary mucinous neoplasm derived from ectopic pancreas: A systematic review

BACKGROUND: Clinicopathological characteristics of intraductal papillary mucinous neoplasm derived from the ectopic pancreas have not been elucidated owing to its rarity. METHODS: MEDLINE databases from 1985 to 2021 were searched. Data regarding patient characteristics, diagnostic modalities, treatment, and prognosis were extracted from the identified articles. RESULTS: Comprehensive data on 13 patients (10 men and 3 women) with intraductal papillary mucinous neoplasm derived from ectopic pancreas were extracted. The median age was 69 years (range, 42–80 years). The tumors were located in the stomach in 6 patients, the duodenum in 1 patient, jejunum in 3 patients, ileum in 1 patient, and Meckel diverticulum in 2 patients. Histopathological examination revealed intraductal papillary mucinous neoplasm in 10 patients and intraductal papillary mucinous carcinoma in 3 patients. The median size of the tumor was not significantly different between the intraductal papillary mucinous carcinoma group and the intraductal papillary mucinous neoplasm group (P = .611). CONCLUSION: Accurate preoperative diagnosis and differential diagnosis between intraductal papillary mucinous neoplasm and intraductal papillary mucinous carcinoma remain difficult despite recent advances in imaging modalities.