Mo1302 THE ACCURACY AND AGREEMENT OF CT/MRI AND EUS IN IDENTIFICATION OF WORRISOME FEATURES WHEN COMPARED TO SURGICAL PATHOLOGY IN MUCINOUS PANCREAS CYSTS

Abstract

The ideal management of patients with mucinous pancreas cysts is controversial. Non-invasive imaging modalities including CT/MRI and EUS have been utilized to select patients appropriate for surgical resection via identification of worrisome features (WF). It remains unclear, however, if WF on CT/MRI or EUS is accurate. Using a prospectively maintained surgical database, we identified consecutive patients with established intraductal papillary mucinous neoplasm (IPMN) and mucinous cystic neoplasm (MCN) of the pancreas at our tertiary care referral center between 2012 and 2017 who underwent surgical resection. All identified patients underwent pre-operative contrast-enhanced CT and/or gadolinium enhanced MRI and EUS. High risk stigmata (HRS) was defined as obstructive jaundice, enhanced solid component, or main pancreatic duct (MPD) >10mm. WF was defined as cyst size >3cm, thickened enhanced cyst walls, non-enhanced mural nodules, or MPD dilation >5mm. Surgical pathology from pancreatic resections was reviewed for WF and final pathology. The main outcome measure was agreement of WF on CT/MRI and EUS with surgical pathology. Additionally, the association between WF in CT/MR and EUS with malignancy was determined. We identified 106 patients with pancreas cysts whom underwent surgical resection. Sixty-two patients were identified with mucinous cysts. There were 22 male and 40 female patients (65%) in the study group. The median age was 68. The mean cyst size was 3.09 cm. Twenty-eight patients (45%) had any WF on CT/MRI vs. 39 patients (63%) on EUS. Twenty-four patients (39%) had any WF on both CT/MRI and EUS. HRS was present in 4 patients (6%) (Table 1). Size agreement (intraclass correlation) between CT/MRI and pathology was 69% (95% CI, 54% – 80%) whereas EUS to pathology was 77% (95% CI, 63% - 85%). The agreement between WF variables and surgical pathology appeared best for cyst size >3cm on EUS: absolute agreement 0.79 (kappa coefficient 0.57). Each variable was evaluated alone for relationship with malignancy. MPD dilation on CT/MRI had a 5.23 increased risk of malignancy (OR=5.23, 95%CI 1.44,19.0). Twenty-four patients (39%) had malignant cysts (17 with HGD, 7 invasive carcinoma). Using final pathology as reference, performance characteristics were calculated for WF on CT/MRI vs. EUS (Table 2). EUS appears to be more accurate than CT/MRI for cyst size. This is clinically relevant as size is a frequent measure used to determine surgical management. Unfortunately, the overall sensitivity of CT/MRI and EUS in identifying malignant cysts via WF appears to be low; though some features have high specificity. Other modalities in the pre-operative evaluation of mucinous cysts are likely needed.Table 2: Performance Characteristics of Worrisome Features for MalignancyView Large Image Figure ViewerDownload Hi-res image Download (PPT)