Plain Computed Tomography for Differentiating Neoplastic and Non-neoplastic Pedunculated Gallbladder Polyps.

Area of Science:

• Radiology
• Gastroenterology
• Surgical Pathology

Background:

• Large pedunculated gallbladder polyps (PGPs) ≥10 mm often warrant surgical resection due to potential neoplastic changes.
• Histopathological examination post-resection frequently reveals non-neoplastic polyps (non-NPs), despite pre-operative suspicion of neoplastic polyps (NPs).
• Accurate pre-operative differentiation between NPs and non-NPs is crucial for appropriate patient management and surgical planning.

Purpose of the Study:

• To evaluate the diagnostic utility of plain computed tomography (CT) in differentiating neoplastic polyps (NPs) from non-neoplastic polyps (non-NPs) in patients with large PGPs.
• To assess the polyp detection rate (PDR) and CT value differences between NPs and non-NPs using plain CT imaging.

Main Methods:

• Retrospective analysis of 46 patients with PGPs ≥10 mm who underwent both plain and contrast-enhanced CT (CE-CT) prior to cholecystectomy.
• Assessment of polyp detection rate (PDR) on plain CT and calculation of CT value differences between PGPs and surrounding bile.
• Comparison of imaging findings with final histopathological diagnoses.

Main Results:

• Neoplastic polyps (NPs) were detected in 21 patients, while 25 had non-NPs.
• The PDR for NPs on plain CT was significantly higher (38%) compared to non-NPs (0%) (p <0.01).
• A significantly larger difference in CT values between NPs and surrounding bile was observed compared to non-NPs (14.12 ± 11.38 HU vs. 5.04 ± 6.15 HU, p <0.01).

Conclusions:

• Plain CT demonstrates a high probability of detecting neoplastic polyps (NPs) in large pedunculated gallbladder polyps (PGPs).
• Plain CT is a valuable tool for differentiating between neoplastic and non-neoplastic polyps pre-operatively.
• The findings support the use of plain CT in guiding surgical decisions for large PGPs.