Interobserver Agreement for Detection of Malignant Features of Intraductal Papillary Mucinous Neoplasms of the Pancreas on MDCT

Abstract

OBJECTIVE The purpose of this retrospective study was to measure interobserver agreement in the assessment of malignant imaging features of intraductal papillary mucinous neoplasms (IPMNs) on MDCT. MATERIALS AND METHODS Pancreatic protocol CT studies were reviewed for 84 patients with resected IPMNs. Maximal diameter of the dominant cyst, presence of a mural nodule, presence of a solid component, and diameters of the main pancreatic duct (MPD) and common bile duct (CBD) were measured by four radiologists independently. In each patient, the IPMN was classified into one of three types: main duct, branch duct, or mixed IPMN. Interobserver agreement of lesion features was examined using the intraclass correlation coefficient (ICC) for continuous features and Fleiss kappa for categorical features. RESULTS The final dataset included 55 branch duct IPMNs, nine main duct IPMNs, and 20 mixed IPMNs. Moderate agreement (κ = 0.458; 95% CI, 0.345–0.564) was observed in assigning branch duct, main duct, or mixed IPMN subtypes. Measurement agreement was substantial to excellent for dominant cyst (ICC = 0.852; 95% CI, 0.777–0.907), MPD (0.753, 0.655–0.837), and CBD (0.608, 0.463–0.724) but only fair to moderate for the detection of the presence of mural nodule (κ = 0.284, 0.125–0.432) or solid component (κ = 0.405, 0211–0.577). CONCLUSION Substantial to excellent interobserver agreement in the measurement of cyst diameter, MPD, and CBD support their use for characterizing malignant features of IPMN on MDCT. However, the subjective interpretation of the presence of solid components and mural nodules by individual radiologists was more variable.

Management of branch-duct intraductal papillary mucinous neoplasms: a large single-center study to assess predictors of malignancy and long-term outcomes

“…A possible explanation may be the limitation of CT/MRI in identifying features associated with malignancy in BD-IPMNs, particularly mural nodules. 21 Interestingly, we observed that 28% of mural nodules detected by EUS were missed by CT/MRI in the malignant group; with cyst size ranging between 2.1-3.5 cm. Among the malignant mural nodules missed by CT/MRI (n=4), 2 did not have any WF.…”

Main-duct Intraductal Papillary Mucinous Neoplasm

“…28 This fact underlines the strength of MPD diameter in the diagnostic evaluation. Beyond MPD diameter, mural nodules and symptoms are identified as predictors of malignancy in IPMNs with main pancreatic duct involvement in the current literature.…”

Impact of next-generation sequencing on the clinical diagnosis of pancreatic cysts

“…These findings support the value of NGS, given that the preoperative diagnosis of pancreatic cysts can be quite challenging, especially in centers without significant experience. 18,[43][44][45][46] Biochemical and cytologic analysis are valuable ancillary tests of pancreatic cyst fluid; however, appropriate specimen handling (eg, maintaining the cyst fluid fresh without dilution) and routine triage of cyst fluid for biochemical analysis is not always performed. In addition, CEA levels are not always elevated in mucinous cysts as shown in a significant number of the mucinous cysts in this study, and various cut points in CEA level supportive of a mucinous cyst affect accuracy.…”