Prediction of Malignancy With Endoscopic Ultrasonography in Patients With Branch Duct–Type Intraductal Papillary Mucinous Neoplasm

Abstract

Objective: We evaluated the accuracy of a new endoscopic ultrasonography (EUS) scoring system to predict malignancy in branch duct-type intraductal papillary mucinous neoplasms (BD-IPMNs).Methods: We performed a retrospective multicenter study of patients who underwent EUS within 3 months before surgery and were diagnosed as having BD-IPMNs by postoperative pathologies at 8 hospitals in Korea from August 2002 to December 2011. To predict the malignancy, we applied the EUS scoring system consisting of pancreatic cyst size, height of mural nodules, main duct dilatation, septal thickening, and patulous orifice. We evaluated the diagnostic accuracy of the new EUS scoring system and compared it with previous individual risk factors.Results: Eighty-four patients (male-to-female ratio, 55:29; mean [SD] age, 64.7 [7.1] years) had 68 benign BD-IPMNs and 16 malignant intraductal papillary mucinous neoplasms. The EUS scoring system showed 75.0% sensitivity and 94.1% specificity at 7 points. This system (area under the curve, 0.939; 95% confidence interval, 0.884-0.994) resulted in a more accurate prediction than the previous known other factors including Sendai criteria, dilatation of ducts, size of the cyst, and presence of septal thickening and mural nodules.Conclusions: The EUS scoring system predicted BD-IPMN malignancy more accurately than the Sendai criteria and individual risk factors.Key Words: endoscopic ultrasonography, branch duct-type intraductal papillary mucinous neoplasm, malignancy, diagnostic accuracy (Pancreas 2014;43: 1306-1311 I ntraductal papillary mucinous neoplasms (IPMNs) of the pancreas are grossly detectable, mucin-producing, and potentially malignant pancreatic cystic neoplasms. Intraductal papillary mucinous neoplasms are pathologically graded according to the most atypical area in the lesion such as low-grade adenoma, moderate dysplasia, carcinoma in situ, and invasive carcinoma. The prognosis of low-grade adenoma and moderate dysplasia is good but that of carcinoma is similar to pancreatic cancers.If the IPMN involves the main pancreatic duct, the risk for malignancy is 57% to 92%. However, in the case of branch duct-type IPMN (BD-IPMN), the risk for malignancy varies. Several factors have been suggested to discriminate a malignancy from benign BD-IPMN. 1 Abdominal pain, jaundice, pancreatitis, and abrupt onset diabetes mellitus are clinically related with malignancy. In radiological findings, the risk for malignancy is high if a large cyst (>30 mm) is present, the main pancreatic duct is dilated, and solid components such as mural nodules, infiltrative mass, or a thickened septum exist.Several criteria for surgically managing a pancreatic cystic neoplasm have been suggested, but predicting the malignancy of BD-IPMN before surgery is still challenging. The Sendai criteria are the most widely accepted to determine whether a surgical resection of BD-IPMN is indicated, but the frequency of malignancy is 28% when they are applied to resected cases. 2 Endoscopic ultrasonography (EUS) is the best ...

Plectin-1 as a Biomarker of Malignant Progression in Intraductal Papillary Mucinous Neoplasms

“…Present clinical and imaging criteria for assessing malignant risk in IPMN are not wholly accurate 5–7 and could be improved through the further use of robust molecular or protein-based biomarkers. Our findings here and those of prior studies indicate that increased expression of Plectin-1 is a molecular harbinger of malignant progression that might be suitably leveraged for the clinical assessment of IPMN either prior to and after surgery.…”

“…Given the potential risks associated with surgery 3,4 , significant efforts have been made to define robust clinical and imaging criteria that accurately differentiate malignant/high risk IPMNs requiring surgical resection from benign/low risk IPMNs that can be managed conservatively. While established guidelines are useful in stratifying risk, they still do not accurately identify all patients who do or do not require surgery 5–7 , highlighting the need for additional criteria such as biomarkers to improve diagnostic accuracy 8–11 . One such promising biomarker is Plectin-1, previously shown to be expressed at later stages of pancreatic neoplastic progression, including high grade pancreatic intraepithelial neoplasia and most invasive PDAs 12,13 , as well as in malignant IPMNs 14 .…”

Endosonography in the diagnosis and management of pancreatic cysts

“…More studies are needed using the newer MRI machines. A recent multicenter study from Korea examined 84 resected BD-IPMNs in order to evaluate EUS predictors of malignancy in BD-IPMNs [28] . An EUS scoring system (0-10) was developed in which points were assigned based on cyst size, mural nodules, pancreatic duct dilation, thick septa and the characteristic "patulous" papilla [28] .…”

“…A recent multicenter study from Korea examined 84 resected BD-IPMNs in order to evaluate EUS predictors of malignancy in BD-IPMNs [28] . An EUS scoring system (0-10) was developed in which points were assigned based on cyst size, mural nodules, pancreatic duct dilation, thick septa and the characteristic "patulous" papilla [28] . This scoring system was found to have an overall area under the curve of 0.944 with 75% sensitivity and 94% specificity for malignant BD-IPMN using an EUS score cutoff of ≥ 7.…”

Value of apparent diffusion coefficient for predicting malignancy of intraductal papillary mucinous neoplasms of the pancreas

“…However, a study showed that not all imaging features of the cysts should be weighted equally for assessing the malignancy of IPMN (8). The International Consensus Guidelines suggest that pancreatic cysts with "worrisome features" and cysts larger than 3 cm without "worrisome features" should be further evaluated by endoscopic ultrasonography (EUS) (2), which improves the accuracy of differentiating benign from malignant IPMNs (9). However, EUS is known to present difficulties because of its operator dependence and its low negative predictive value for fine-needle aspiration cytology (10).…”