Immunoglobulin G4-related cholecystitis mimicking a locally advanced gallbladder cancer-a case report and review of literature

Xanthogranulomatous cholecystitis with histologic features suggestive of IgG4 related cholecystitis - A morphologic overlap with IgG4 related disease

AIMS

Both xanthogranulomatous cholecystitis (XGC) and IgG4-related cholecystitis (IgG4-CC) are rare chronic fibroinflammatory tumefactive diseases of the gallbladder, which cause a strong confusion with resectable malignancy in view of their mass forming tendency with extension into the liver. We aim to study the histopathologic features of xanthogranulomatous cholecystitis with regard to IgG4-related cholecystitis in extended cholecystectomy specimens.

METHODS AND RESULTS

Sixty cases of extended cholecystectomy with liver wedge resection, diagnosed as XGC on histopathology from January 2018 to December 2021 were retrieved from the archives. Representative sections were reviewed by two pathologists independently. Immunohistochemistry was performed for IgG4 and IgG4/IgG was derived. The cases were dichotomized in two groups on the basis of IgG4 positive plasma cells. Six cases with >50 IgG4 positive plasma cells had storiform fibrosis, IgG4/IgG ratio >0.40 and extra-cholecystic extension. Of these, 50 % had obliterative phlebitis and 66.7 % had perineural plasma cell wrapping.

CONCLUSIONS

A small subset of XGC cases (~10 %) had morphologic overlap with IgG4-CC, but should not be overcalled as the diagnosis of IgG4-RD requires an integrative approach based on clinical, serologic and imaging criteria and not solely on histopathology.

Misdiagnosis of carcinoma gall bladder in endemic regions

Background

Incidental carcinoma gall bladder and benign disease in radical cholecystectomy specimen is the cause of concern. We attempted to find out the incidence and reasons thereof in the present study.

Methods

Present study is a retrospective analysis of a prospectively maintained database between July 2002 and July 2019. All patients with a diagnosis of carcinoma gall bladder admitted for surgery were included.

Results

Out of 148 patients, 110 patients had carcinoma gall bladder (CAGB), while 38 patients (25.7%) had incidental carcinoma (under-diagnosis). Radical resection was done in 61/110 (55.4%) patients with clinical CAGB, where 15 (24.6%) patients had benign pathology (“over-diagnosis”). Overdiagnosis was due to xanthogranulomatous cholecystitis (n = 9), chronic cholecystitis (n = 2), tuberculosis (n = 2) and IgG4 related cholecystitis (n = 2). Among 61 patients, a history of weight loss and anorexia were significantly associated with malignancy. Asymmetrical wall thickness was significantly more common in benign mimickers.

Among patients with incidental carcinoma, preoperative ultrasonography reported normal wall thickness of gall bladder in 28 (73.7%), thickened gall bladder wall in 6, and polyp in 3 patients. The resectability rate among incidental carcinoma was 27/38 (71.05%).

Conclusion

Over-diagnosis of the carcinoma gall bladder was present in 24.6%. On the other hand, incidental carcinoma comprised 25.7% of all admissions for carcinoma gall bladder with resectability of 71%.

Isolated IgG4-related cholecystitis with localized gallbladder wall thickening mimicking gallbladder cancer: a case report and literature review

BACKGROUND

IgG4-related cholecystitis, which is a manifestation of IgG4-related disease in the gallbladder, is associated with autoimmune pancreatitis or IgG4-related sclerosing cholangitis in most cases; isolated gallbladder lesions without systemic manifestations are very rare. Gallbladder wall thickening is often diffuse, but sometimes localized, in which case, differentiation from gallbladder cancer becomes difficult. The characteristic features of IgG4-related cholecystitis on imaging that would enable differentiation from gallbladder cancer remain poorly described.

CASE PRESENTATION

We present a rare case of isolated IgG4-related cholecystitis with localized gallbladder wall thickening that was clinically difficult to distinguish from malignancy before resection. An 82-year-old man was referred to our hospital because of gallbladder wall thickening on abdominal ultrasonography without any symptoms. Dynamic computed tomography of the abdomen showed localized wall thickening from the body to the fundus of the gallbladder that was enhanced from an early stage with a prolonged contrast effect. There were no other findings, such as pancreatic enlargement and bile duct dilatation. Magnetic resonance cholangiopancreatography revealed neither dilatation nor stenosis of the bile duct and pancreatic duct. Endoscopic ultrasonography (EUS) showed a smooth layered thickening of the gallbladder wall with a maximum thickness of 6 mm and a well-preserved outermost hyperechoic layer in the same area. Laparoscopic cholecystectomy was performed because malignancy could not be completely ruled out. Pathological examination of a resected specimen revealed IgG4-positive plasma cell infiltration, fibrosis, and phlebitis. Although the serum IgG4 level measured after resection was normal, the condition was ultimately diagnosed as probable IgG4-related cholecystitis according to the 2020 revised comprehensive diagnostic criteria for IgG4-related disease. The EUS images reflected the pathological findings, in which lymphocytic infiltration was distributed in a laminar fashion in the gallbladder wall.

CONCLUSIONS

Although rare, isolated IgG4-related cholecystitis with localized wall thickening mimicking gallbladder cancer remains a clinical problem. A smooth laminar thickening of the gallbladder wall on EUS imaging could be one of the most informative characteristics for differentiating IgG4-related cholecystitis from gallbladder cancer.

Clinical and Image Characteristics of IgG4-Related Sclerosing Cholecystitis

Since autoimmune pancreatitis (AIP) was established as a new disease entity, sclerosing change with abundant immunoglobulin-4 (IgG4)-positive plasma cells, storiform fibrosis, and obliterative phlebitis are main pathological features in IgG4-related diseases. Regarding IgG4-related sclerosing cholecystitis (IgG4-CC), which is occasionally associated with AIP cases and is rarely isolated, there are no diagnostic criteria and insufficient perceptions of the image findings. Although there have been some reports on IgG4-CC, differentiation between IgG4-CC and gallbladder cancer is very difficult in some cases with a localized lesion. In this review, we especially focused on image findings of IgG4-CC and summarized its image features for diagnostic assistance. The ultrasonography and CT findings of IgG4-CC could be classified into diffuse and localized types. Based on these findings, the presence of wall thickening with an intact or smooth mucosal layer, followed by a homogenously thickened outer layer, would be a helpful morphological finding to distinguish IgG4-CC from gallbladder cancer.