Objective: To systematically determine the imaging findings for distinguishing malignant and benign branch-duct type intraductal papillary mucinous neoplasms (BD-IPMNs), including mixed type, and their diagnostic value through meta-analysis of published studies.
Background: Management of BD-IPMNs, including mixed type, largely relies on imaging findings. The current knowledge on imaging findings to distinguish malignant and benign BD-IPMNs has weak evidence and is mostly from scattered individual retrospective studies.
Methods: Thorough literature search in Ovid-MEDLINE and EMBASE databases was conducted to identify studies where findings of computed tomography, magnetic resonance imaging, and endoscopic ultrasonography of BD-IPMNs with or without main pancreatic duct (MPD) dilatation were correlated with surgical/pathological findings. Review of 1128 article candidates, including full-text review of 102 articles, identified 23 eligible articles with a total of 1373 patients for meta-analysis. Dichotomous data regarding distinction between malignant and benign BD-IPMNs were pooled using random effects model to obtain the diagnostic odds ratios (DORs) and their 95% confidence intervals (CIs) of various individual imaging findings for diagnosing malignant BD-IPMN.
Results: Presence of mural nodules revealed the highest pooled DOR (95% CI) of 6.0 (4.1–8.8) followed by MPD dilatation [3.4 (2.3–5.2)], thick septum/wall [unadjusted, 3.3 (1.5–6.9); publication bias-adjusted, 2.3 (0.9–5.5)], and cyst size greater than 3 cm [2.3 (1.5–3.5)]. Multilocularity and multiplicity of the cystic lesions did not reveal statistically significant association with malignancy.
Conclusions: Presence of mural nodules should be regarded highly suspicious for malignancy warranting a surgical excision whereas cyst size greater than 3 cm, MPD dilatation (5–9 mm), or thick septum/wall may better be managed by careful observation and/or further evaluation.
We aim to determine the imaging findings for differentiating malignant and benign BD-IPMNs (branch-duct type intraductal papillary mucinous neoplasms) and their diagnostic value through meta-analysis. Pooled diagnostic odds ratio with which to suggest malignant BD-IPMN was the highest for the presence of mural nodule, followed by main pancreatic duct dilatation, defined as diameter 5 to 7 mm, thick septum/wall, and cyst size greater than 3 cm.
*Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
†Department of Imaging, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
‡The Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, MA; and
§Department of Radiology, Seoul National University Hospital, Seoul, Korea.
Reprints: Seong Ho Park, MD, PhD, Department of Radiology, University of Ulsan College of Medicine, Asan Medical Center, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 138-736, Korea. E-mail: firstname.lastname@example.org.
Disclosure: S.H.P. has received research grants from GE Healthcare and Dongkook Pharmaceutical, which are unrelated to the submitted work. There is nothing to disclose for the other authors, and the authors declare no conflicts of interest.