Department of Pathology, Vanderbilt University Medical Center, Nashville, TN 37232 USA.
Hum Pathol. 2012 Jan;43(1):1-16. doi: 10.1016/j.humpath.2011.04.003. Epub 2011 Jul 20.
Intraductal papillary mucinous neoplasm (IPMN) is a grossly visible (≥1 cm), mucin-producing neoplasm that arises in the main pancreatic duct and/or its branches. Patients with intraductal papillary mucinous neoplasm can present with symptoms caused by obstruction of the pancreatic duct system, or they can be asymptomatic. There are 3 clinical subtypes of intraductal papillary mucinous neoplasm: main duct, branch duct, and mixed. Five histologic types of intraductal papillary mucinous neoplasm are recognized: gastric foveolar type, intestinal type, pancreatobiliary type, intraductal oncocytic papillary neoplasm, and intraductal tubulopapillary neoplasm. Noninvasive intraductal papillary mucinous neoplasms are classified into 3 grades based on the degree of cytoarchitectural atypia: low-, intermediate-, and high-grade dysplasia. The most important prognosticator, however, is the presence or absence of an associated invasive carcinoma. Some main duct-intraductal papillary mucinous neoplasms progress into invasive carcinoma, mainly tubular adenocarcinoma (conventional pancreatic ductal adenocarcinoma) and colloid carcinoma. Branch duct-intraductal papillary mucinous neoplasms have a low risk for malignant transformation. Preoperative prediction of the malignant potential of an intraductal papillary mucinous neoplasm is of growing importance because pancreatic surgery has its complications, and many small intraductal papillary mucinous neoplasms, especially branch duct-intraductal papillary mucinous neoplasms, have an extremely low risk of progressing to an invasive cancer. Although most clinical decision making relies on imaging, a better understanding of the molecular genetics of intraductal papillary mucinous neoplasm could help identify molecular markers of high-risk lesions. When surgery is performed, intraoperative frozen section assessment of the pancreatic resection margin can guide the extent of resection. Intraductal papillary mucinous neoplasms are often multifocal, and surgically resected patients should be followed for metachronous disease.
导管内乳头状黏液性肿瘤（IPMN）是一种在主胰管及其分支中发生的肉眼可见（≥1cm）、产生黏液的肿瘤。IPMN 患者可出现胰管系统阻塞引起的症状，也可无症状。IPMN 有 3 种临床亚型：主胰管型、分支胰管型和混合型。IPMN 有 5 种组织学类型：胃小凹型、肠型、胰胆管型、导管内嗜酸细胞性乳头状肿瘤和导管内管状乳头状肿瘤。非浸润性导管内乳头状黏液性肿瘤根据细胞结构异型程度分为 3 级：低级别、中级别和高级别异型增生。然而，最重要的预后因素是是否存在伴发的浸润性癌。一些主胰管导管内乳头状黏液性肿瘤进展为浸润性癌，主要为管状腺癌（常规胰导管腺癌）和胶样癌。分支胰管导管内乳头状黏液性肿瘤恶性转化的风险较低。术前预测导管内乳头状黏液性肿瘤的恶性潜能越来越重要，因为胰腺手术有其并发症，许多小的导管内乳头状黏液性肿瘤，尤其是分支胰管导管内乳头状黏液性肿瘤，进展为浸润性癌的风险极低。尽管大多数临床决策依赖于影像学，但对导管内乳头状黏液性肿瘤分子遗传学的更好理解可能有助于识别高危病变的分子标志物。当进行手术时，对胰腺切除边缘的术中冷冻切片评估可以指导切除范围。导管内乳头状黏液性肿瘤通常是多灶性的，接受手术切除的患者应随访是否有同时性疾病。
