Clinical strategies for differentiating IgG4-related cholecystitis from gallbladder carcinoma to avoid unnecessary...

Immunoglobulin G4 (IgG4)-related cholecystitis (IgG4-C) is often difficult to distinguish from gallbladder carcinoma (GBC). This study aimed to determine a practical strategy for differentiating between IgG4-C and GBC to avoid unnecessary surgical resection. The expression of IgG4 in the gallbladder was detected by immunohistochemistry. The clinicopathological and radiological characteristics of IgG4-C patients and GBC patients were analyzed retrospectively. Immunohistochemistry revealed that IgG4 was upregulated in the plasma cells of IgG4-C tissues. The median serum total bilirubin levels were significantly higher in the patients with IgG4-C than in those with GBC (45.8 µmol L^-1 vs. 29.9 µmol L^-1). The serum γ-GGT levels were higher in IgG4-C patients than in GBC patients, whereas the serum levels of CA125 were significantly higher in GBC patients than in IgG4-C patients. The imaging scans were helpful for differentiating IgG4-C from GBC based on the presence of a layered pattern and Rokitansky-Aschoff sinuses in the gallbladder wall. There were no statistically significant differences in age, presence of abdominal pain, level of emaciation between the two groups. Our study demonstrated that the combination of imaging with serum total bilirubin, γ-GGT and CA125 levels can offer added preoperative diagnostic value and reduce the rate of IgG4-C misdiagnosis.