Intraductal papillary mucinous neoplasm of pancreas: analysis of the clinicopathologic features and prognosis / 中华病理学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To study the clinicopathologic and immunohistochemical features, and the prognosis of intraductal papillary mucinous neoplasms (IPMN) of the pancreas.</p><p><b>METHODS</b>The clinical findings, morphologic features, immunophenotype and prognosis were investigated in 61 cases of IPMN.</p><p><b>RESULTS</b>Of these 61 cases, 33 were in the pancreatic head and 14 were in the body and tail, and 14 in the entire pancreas. The average patients' age was 61.8 years. The initial symptom was abdominal pain in 37 cases, and the tumors were detected at routine checkup in 14 cases. The imaging examination showed dilated ducts and/or cystic and solid masses. Grossly, 32 cases were multi-loculated cystic masses containing mucin and papillary areas; 13 cases were solid. Microscopically, the IPMN showed four patterns, including gastric-type (16 cases), intestinal-type (21 cases), pancreatobiliary-type (21 cases) and eosinophilic-type (3 cases). The IPMN cohort included 13, 13 and 6 IPMN with low, intermediate and high-grade dysplasia respectively, and 29 IPMN associated with invasive carcinoma. The IPMN associated carcinomas were mainly ductal adenocarcinoma (23/29, 79.3%), followed by colloid carcinoma (4/29, 13.8%) and undifferentiated carcinoma (2/29, 6.9%). Immunohistochemically, IPMN expressed MUC5AC (51/57, 89.4%), MUC2 (21/57, 36.8%), and MUC1 (13/46, 28.3%). The mean postoperative follow-up period was 32 months (range 12-112 months). Six of 61 patients were lost to follow-up. Overall 5-year survival rate was 76%. The 5-year survival rate of IPMN with low, intermediate or high-grade dysplasia was 100%, and recurrence was local in 3 patients. The 3-year survival rate of IPMN associated with invasive carcinoma was 55%. 12 of 13 patients died within 2 years after operation.</p><p><b>CONCLUSIONS</b>IPMN is a common cystic neoplasm of the pancreas located in the ducts. The pathologic types and classifications are clearly defined. MUC stains are helpful for the diagnosis and papillary typing. IPMN with invasive carcinoma was associated with significantly worse survival than IPMN with dysplasia.</p>