[Intraductal papillary mucinous neoplasm of pancreas: a clinicopathologic and immunohistochemical study of 19 cases].
OBJECTIVE
To study the clinicopathologic features and diagnosis of intraductal papillary mucinous neoplasm (IPMN) of the pancreas.


METHODS
Nineteen cases of IPMN encountered during the period from 1999 to 2007 were studied by light microscopy and immunohistochemistry.


RESULTS
IPMN occurred more often in males (68%). It affected patients in older age group (mean age = 59) and was located mainly in the head of pancreas (60%). The mean tumor size was 4.2 cm (range = 1 to 8 cm). The clinical presentation was epigastric pain (53%), weight loss (32%), diabetes (21%), pancreatitis (21%) and jaundice (10%). Pancreatectomy was performed in 18 cases. The remaining patient received bypass surgery only. Features of in-situ or invasive malignancy were present in 15 of the 19 cases (78%). Histologically, the tumor consisted of papillary proliferations protruding into and expanding the pancreatic ducts. Invasion into the surrounding pancreatic parenchyma was noted in 12 cases and chronic pancreatitis was present in 16 cases. Follow-up data (4 to 48 months) were available in 13 patients. Apart from 1 patient who died of other disease, all were still alive. Immunohistochemical study showed that p53 was positive in 6 cases, p16 in 5 cases and fascin in 8 cases. The expression of c-erbB-2 was all negative. Ki-67 index ranged from 1% to 80% (mean = 38%).


CONCLUSIONS
Malignant changes are not uncommon in IPMN. The prognosis after surgical resection however is better than that of conventional pancreatic adenocarcinoma. The overexpression of p53, p16 and fascin may be related to tumor progression. The possibility of malignant transformation needs to be considered if the Ki-67 index is over 15%. Early recognition by radiologic examination (including ERCP) and pancreatic cytology would be helpful in early diagnosis. Surgical resection represents the mainstay of treatment and long-term post-operative follow up is needed.
Huo
Zhen
Z
Department of Pathology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing 100730, China.
Yang
Di
D
Chang
Xiao-Yan
XY
Wan
Jian-Wei
JW
Chen
Jie
J
D048868:Adaptor Proteins, Signal Transducing / Q000032:analysis; D002288:Adenocarcinoma, Mucinous / Q000175:diagnosis / Q000378:metabolism; D000328:Adult; D000368:Aged; D021441:Carcinoma, Pancreatic Ductal / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology*; D002291:Carcinoma, Papillary / Q000473:pathology*; D018797:Cell Cycle Proteins / Q000032:analysis; D002760:Cholangiopancreatography, Endoscopic Retrograde; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000639:trends*; D019394:Ki-67 Antigen / Q000032:analysis; D008297:Male; D008875:Middle Aged; D010179:Pancreas / Q000378:metabolism / Q000473:pathology; D010180:Pancreatectomy; D010183:Pancreatic Ducts / Q000378:metabolism / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology*; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis; D016896:Treatment Outcome
D048868:Adaptor Proteins, Signal Transducing; D018797:Cell Cycle Proteins; D019394:Ki-67 Antigen; D018719:Erb-b2 Receptor Tyrosine Kinases; C500695:CDCA5 protein, human