Enhancement Patterns of Malignant Gallbladder Masses at Multiphasic Contrast-enhanced CT: Associations With Clinicoradiopathological Features

Purpose

To assess the enhancement patterns of malignant gallbladder masses at multiphasic contrast-enhanced computed tomography (CECT) and their association with the clinicoradiopathological features.

Material and methods

In this retrospective study, consecutive patients with mass-forming gallbladder cancer (GBC) who underwent biphasic [hepatic arterial phase (HAP) and portal venous phase (PVP)] CECT between January 2019 and January 2023 were included. The enhancement patterns at CT scans were assessed independently by two radiologists blinded to the clinicopathological data. The masses were categorized into the typical group (hypoattenuation relative to normal liver in HAP) and the atypical group (isoenhancement or hyperenhancement in HAP). Enhancement patterns in PVP were also evaluated. The association between enhancement characteristics and the pathological grade and type, radiological aggressiveness (biliary/vascular involvement, lymph node, liver, and omental metastases), resectability, and overall survival was assessed.

Results

Sixty-five patients (41 females, mean age was 52.5 ± 17.6 years) were included in the study. On HAP images, eight lesions (12.3%) were hyperattenuating, nine (13.8%) were isoattenuating, and 48 (73.8%) were hypoattenuating. Of the 17 masses in the atypical group, 8 (47.1%) lesions showed washout, and 9 showed persistent enhancement (52.9%) in the PVP. Heterogeneous peripheral and central enhancement in HAP were significantly associated with lymph node metastases (P = 0.019). Enhancement pattern was not significantly associated with pathological grade/type, other radiological features, resectability, and overall survival.

Conclusion

Mass-forming GBC has variable enhancement. Heterogeneous HAP enhancement is associated with lymph node metastases.