A scoring system based on computed tomography for the correct diagnosis of xanthogranulomatous cholecystitis

BACKGROUND: Xanthogranulomatous cholecystitis (XGC) is an uncommon variant of chronic cholecystitis. The differential diagnoses of XGC include gallbladder cancer (GBC), adenomyomatosis, and actinomycosis of the gallbladder. PURPOSE: To assess the usefulness of computed tomography (CT) findings in the diagnosis of XGC and differentiation from GBC. MATERIAL AND METHODS: We retrospectively assessed the pathological and radiological records of 13 patients with pathologically proven XGC and 33 patients with GBC. RESULTS: Significant differences were observed for the following five CT findings: diffuse wall thickening (XGC = 85%, GBC = 15%, P < 0.01); absence of polypoid lesions (XGC = 100%, GBC = 48%, P < 0.01); intramural nodules or bands (XGC = 54%, GBC = 9%, P < 0.01); pericholecystic infiltration (XGC = 69%, GBC = 9%, P < 0.01); and pericholecystic abscess (XGC = 23%, GBC = 0%, P = 0.018). We defined the scoring system based on how many of the five CT findings were observed. Our scoring system, which included these findings, revealed that patients with three or more findings had sensitivity of 77% (95% confidence interval [CI] = 57–87) and specificity of 94% (95% CI = 86–98). CONCLUSION: Our scoring system can assist in the differentiation of XGC from GBC.