Frequency and significance of calcification in IPMN

The frequency and significance of calcification in intraductal papillary mucinous neoplasms (IPMN) are unknown. We examined calcifications by computed tomography (CT) in a large cohort of IPMNs and correlated them with clinicopathologic characteristics.

Preoperative contrast-enhanced CT imaging studies of 164 patients with surgically resected IPMN were retrospectively reviewed. Morphologic characteristics of IPMN, presence and type of calcifications, their location, the degree of dysplasia and the epithelial subtype were recorded. Symptoms at the time of diagnosis, history of smoking, and alcohol consumption were obtained from medical records.

Of the 164 IPMNs, 68 were branch duct type (Br-IPMN) and 96 main duct (MD-IPMN) or combined type (CT-IPMN); 78 (48%) had a malignant component (CIS and Invasive). Calcifications were present in 33 cases (20%). By type, 16 calcifications were punctate, 11 coarse and 9 eggshell, and by location, 15 were mural, 3 septal, 2 ductal, 1 in the solid component, and 13 in multiple locations. Calcifications were seen more frequently in larger lesions (44 mm vs 32 mm p = 0.002), and when MPD dilation was noted (70% vs 45%, p = 0.023). There was no association between presence of calcification and malignancy, epithelial subtype, or other clinical data. However, malignancy was present in 9/11 IPMN with coarse calcification (p = 0.04), suggesting this may be a worrisome feature.

Calcification is found in 20% of IPMNs, and is more common in larger lesions. Although its overall presence has no correlation with malignancy, coarse calcification, when combined with other morphologic features, may be a radiologic sign of malignancy.