CT and MRI findings of intraductal tubulopapillary neoplasm of the pancreas

To investigate the computed tomography (CT) and magnetic resonance imaging (MRI) characteristics of intraductal tubulopapillary neoplasms (ITPNs) of the pancreas and to correlate these features with clinicopathologic findings for improved preoperative recognition. Eight patients were retrospectively analyzed with surgically confirmed ITPNs treated between October 2015 and June 2024 (median age, 68 years; range, 47–76). All patients underwent preoperative CT, and six underwent MRI. Imaging features, including location, size, morphology, margins, imaging composition, and pancreatic duct dilatation, were assessed. Characteristic signs, such as the “two-tone duct sign” and “cork-of-wine-bottle sign,” were evaluated. Quantitative analysis included unenhanced and peak-enhanced CT attenuation, enhancement amplitude, and apparent diffusion coefficient (ADC) values, compared with adjacent normal pancreatic parenchyma. Lesions predominantly involved the pancreatic head (75%) and were irregular or lobulated in 75% of cases. Ill-defined margins were observed in 75%, and solid–cystic lesion in 25%. Main pancreatic duct dilatation was present in 75% of patients. The “two-tone duct sign” and “cork-of-wine-bottle sign” were detected in 25% and 12.5% of cases, respectively. Quantitative analysis revealed significantly lower enhancement amplitude in ITPNs compared with normal pancreas (35.00 ± 10.58 HU vs. 53.50 ± 11.64 HU, P = 0.03) and a trend toward lower ADC values (1.143 ± 0.312 × 10⁻³ mm²/s vs. 1.372 ± 0.287 × 10⁻³ mm²/s, P = 0.15). ITPNs typically appear as intraductal, poorly enhancing lesions with irregular morphology and frequent pancreatic duct dilatation. Characteristic signs and quantitative imaging parameters can facilitate preoperative recognition, improve diagnostic accuracy, and guide surgical planning.