Diagnostic Accuracy of Preoperative Imaging for Differentiation of Branch Duct Versus Mixed Duct Intraductal Papillary Mucinous Neoplasms.

OBJECTIVE: The aim of this study is to determine the diagnostic accuracy of preoperative evaluation to detect main pancreatic duct involvement in pancreatic cystic lesions thus differentiating mixed intraductal papillary mucinous neoplasm (IPMN) from branch duct (BD)-IPMN. METHODS: The pathology database of pancreatic resections from 2000 to 2014 was reviewed. Main pancreatic duct-IPMNs and IPMNs with intracystic mass/nodules were excluded. The preoperative test characteristics were analyzed using surgical histopathology as the "gold standard." RESULTS: Sixty BD-IPMNs and 23 mixed-IPMNs were identified. Mixed-IPMNs were larger (mean [standard deviation], 4.14 [2.9] vs 2.74 [1.9] mm; P = 0.03) and demonstrated frequent high-grade dysplasia/adenocarcinoma (43% vs 12%, P = 0.004) than BD-IPMNs. Endoscopic ultrasound (EUS) (sensitivity, 80%; specificity, 78%; accuracy, 79%) had the best diagnostic accuracy, whereas magnetic resonance imaging (MRI) (sensitivity, 83%; specificity, 63%; accuracy, 68%) had the highest sensitivity for the diagnosis of mixed-IPMN. A combination of EUS and MRI reached maximum sensitivity but with decreased accuracy (sensitivity, 100%; specificity, 64%; accuracy, 67%). The area under the curve for receiver operation curve was 0.71 whereas the optimal cyst size to detect main duct involvement was 3 cm. CONCLUSIONS: For preoperative evaluation of pancreatic cystic lesions without evidence of intracystic nodules, a combination of MRI and EUS should be considered for improved detection of main duct involvement.

High-grade pancreatic intraepithelial lesions: prevalence and implications in pancreatic neoplasia.

BACKGROUND: High-grade pancreatic intraepithelial neoplasia (PanIN-3), a precursor of pancreatic ductal adenocarcinoma (PDAC), is not universally detected in resected pancreatic neoplasms. We sought to determine the prevalence and prognostic relevance of PanIN-3 lesions in primary surgical resections of PDACs and intraductal papillary mucinous neoplasms (IPMNs). METHODS: A retrospective review of a tertiary care center pathology database (1/2000-6/2014) was performed. Demographics, imaging, pathology, disease-recurrence, and survival data were reviewed. RESULTS: A total of 458 patients who underwent primary pancreatic resection were included. "PanIN-3" lesions were found in 74 (16.2%) patients who either had PDAC (n=67) or main duct (MD)-IPMN (n=7). Among IPMN-MDs, PanIN-3 lesions were exclusively found in those with pathological evidence of chronic pancreatitis. For PDACs, the median overall survival (OS) for pancreata with PanIN-3 lesions was significantly better than those without (OS 1.12 years, inter-quartile range [IQR] 0.72, 2.05 years vs OS 0.86 years, IQR 0.64, 1.60 years respectively; P=0.04). Multivariate Cox regression analysis demonstrated that the presence of PanIN-3 lesions was associated with a reduced risk of death (HR=0.43; 95% CI: 0.23-0.82; P=0.01). CONCLUSIONS: Following primary resection of pancreatic adenocarcinoma, the lower survival observed in patients without PanIN-3 lesions might suggest a state of complete or accelerated transformation. Further investigations are necessary to validate these findings that might impact disease prognosis and management.

Groove Pancreatitis, a Masquerading Yet Distinct Clinicopathological Entity: Analysis of Risk Factors and Differentiation.

OBJECTIVES: Our objective was to delineate predictive factors differentiating groove pancreatitis (GP) from other lesions involving the head of the pancreas (HOP). METHODS: A case-control study of patients older than 10 years was performed comparing patients with GP to those with other surgically resected HOP lesions. RESULTS: Thirteen patients with GP (mean ± SD age, 51.9 ± 10.5 years; 11 males [84.6%]), all with a history of smoking (mean, 37.54 ± 17.8 pack-years), were identified. Twelve patients (92.3%) had a history of heavy alcohol drinking (heavy alcohol [EtOH]). The mean lesion size was 2.6 ± 1.1 cm, and the CA 19-9 was elevated (>37 IU/mL) in 5 patients (45.5%). The most common histopathologic condition was duodenal wall cyst with myofibroblastic proliferation and changes of chronic pancreatitis in the HOP.Univariate analysis revealed decreasing age, male sex, weight loss, nausea/vomiting, heavy EtOH, smoking, and a history of chronic pancreatitis were predictive of GP. A multivariate analysis among smokers demonstrated that weight loss (P = 0.006; odds ratio, 11.96; 95% confidence interval, 2.1-70.2), and heavy EtOH (P < 0.001; odds ratio, 82.2; 95% confidence interval, 9.16-738.1) were most predictive of GP. Compared to pancreatic adenocarcinoma (n = 183), weight loss and heavy EtOH remained predictive of GP. CONCLUSION: Groove pancreatitis in the HOP is associated with a history of heavy EtOH and weight loss. In the absence of these symptoms, it is essential to rule out a malignant lesion.