Xanthogranulomatous cholecystitis: sonographic and CT features and differentiation from gallbladder carcinoma: a pictorial essay

Imaging update on gallbladder adenomyomatosis and its mimics

Radiologists across many imaging modalities commonly encounter gallbladder adenomyomatosis. The classic imaging appearances of gallbladder adenomyomatosis are well described and confirm benignity. However, in clinical practice, adenomyomatosis can be challenging to differentiate from other gallbladder pathologies that require cholecystectomy. In this article, we describe the common and uncommon appearances of gallbladder adenomyomatosis on multimodality imaging, helping differentiate adenomyomatosis from non-benign gallbladder abnormalities. Accurately differentiating adenomyomatosis from its mimics provides the surgical team with important clinical and surgical management information, improving patient outcomes.

Usefulness of MRI Scoring System for Differential Diagnosis between Xanthogranulomatous Cholecystitis and Wall-Thickening Type Gallbladder Cancer

Purpose

To define an MRI scoring system for differentiating xanthogranulomatous cholecystitis (XGC) from wall-thickening type gallbladder cancer (GBC) and compare the diagnostic performance of the scoring system with the visual assessment of radiologists.

Materials and Methods

We retrospectively analyzed 23 and 35 patients who underwent abdominal MRI and were pathologically diagnosed with XGC and wall-thickening-type GBC after surgery, respectively. Three radiologists reviewed all MRI findings. We defined a scoring system using these MRI findings for differentiating XGC from wall-thickening type GBC and compared the area under the curve (AUC) of the scoring system with the visual assessment of radiologists.

Results

Nine MRI findings showed significant differences in differentiating the two diseases: diffuse gallbladder wall thickening (p < 0.001), mucosal uniformity (p = 0.002), intramural T2-high signal intensity (p < 0.001), mucosal retraction (p = 0.016), gallbladder stones (p < 0.001), T1-intermediate to high-signal intensity (p = 0.033), diffusion restriction (p = 0.005), enhancement pattern (p < 0.001), and phase of peak enhancement (p = 0.008). The MRI scoring system showed excellent diagnostic performance with an AUC of 0.972, which was significantly higher than the visual assessment of the reviewers.

Conclusion

The MRI scoring system showed better diagnostic performance than the visual assessment of radiologists to differentiate XGC from wall-thickening-type GBC.

Preoperative differential diagnosis of xanthogranulomatous cholecystitis and gallbladder carcinoma

BACKGROUND

Because the clinical and imaging features of xanthogranu-lomatous cholecystitis (XGC) and gallbladder carcinoma (GBC) are very similar, it is often difficult to distinguish them clinically. Based on abdominal ultrasound and contrast-enhanced CT, this study analyzed the differences in demographic characteristics, laboratory indicators, tumor markers, and imaging features between patients with XGC and those with GBC. Then a diagnostic model was constructed to assist clinicians in the diagnosis and treatment of the two conditions.

AIM

To analyze the differences in clinical and imaging features between XGC and GBC patients, and to establish a diagnostic model for the two conditions.

METHODS

From January 2011 to September 2022, 67 patients with XGC and 139 patients with GBC who underwent abdominal ultrasonography and abdominal contrast-enhanced CT and had definite postoperative pathological diagnosis at Zhejiang Provincial People's Hospital were retrospectively analyzed. The differences in clinical manifestations and laboratory and imaging findings between the two groups were analyzed.

RESULTS

Gender, γ-glutamyl transpeptadase (GGT), carcinoembryonic antigen (CEA), mean gallbladder wall thickness, gallbladder wall thickening pattern (gallbladder wall involvement < 50%), gallstones, and retroperitoneal lymphadenopathy were independent risk factors for differentiating XGC from GBC. The cut-off values for GGT and CEA were 28 U/L and 3.2 ug/L, respectively.

CONCLUSION

There are significant differences in some clinical and imaging features between XGC and GBC, which can provide reference value for their preoperative differential diagnosis.

Xanthogranulomatous Cholecystitis Mimicking Carcinoma Gallbladder

Xanthogranulomatous cholecystitis (XGC) is a rare benign chronic inflammatory disease of the gallbladder that often presents as cholecystitis and can mimic gallbladder carcinoma. Distinguishing XGC from gallbladder cancer preoperatively is challenging. We present a case of a 62-year-old male who presented with features of carcinoma gallbladder in the CECT abdomen and MRCP. Intraoperatively, there was a mass in the gallbladder and extension into the adjacent structures with involvement of the hepatic artery, 1^st part of the duodenum, portal vein, and hepatic flexure of the colon, and thus a palliative cholecystectomy was done. The histopathological report came out as XCG. The case aims to outline the clinical presentation of XGC and differentiate it from carcinoma gallbladder.

Intracystic papillary neoplasm of the gallbladder concomitant with xanthogranulomatous cholecystitis: a case report

BACKGROUND

The intracystic papillary neoplasm (ICPN) is a newly established disease concept. It has been regarded as a preinvasive neoplastic lesion, similar to intraductal papillary mucinous neoplasm of the pancreas. Limited information is available on the clinical and imaging features of ICPN.

CASE PRESENTATION

A 65-year-old woman was referred to our hospital for assessment of a gallbladder tumor. Contrast-enhanced computed tomography showed a papillary tumor in the fundus of the gallbladder with irregular thickening of the gallbladder wall that spread into the cystic duct. The boundary between the tumor and liver was unclear. The patient was diagnosed with gallbladder cancer with liver invasion. We performed extended cholecystectomy with liver bed resection after confirming the absence of cancer cells in the resection margin of the cystic duct. After pathological examination, the tumor was diagnosed as an ICPN with xanthogranulomatous cholecystitis. The patient was discharged on postoperative day 8 with no complications.

CONCLUSIONS

We have described a rare case of ICPN concomitant with xanthogranulomatous cholecystitis. Clinicians should include ICPN as a differential diagnosis in patients with a papillary or polypoid tumor in the gallbladder.

Diagnostic accuracy of imaging modalities in differentiating xanthogranulomatous cholecystitis from gallbladder cancer

BACKGROUND

The aim of this study was to assess the diagnostic performance of radiological imaging in differentiating xanthogranulomatous cholecystitis (XGC) from gallbladder cancer (GBC).

METHODS

A retrospective analysis of the radiological imaging performed in patients who had pathologically confirmed XGC or GBC between December 2004 to April 2016 was performed. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of each imaging modality, and combined imaging modalities were calculated.

RESULTS

A total of 218 patients (XGC =109, GBC =109) were identified; 19 patients received all of abdominal ultrasound (US), contrast-enhanced ultrasound (CEUS), computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET/CT); 21 received four of these imaging examination types; 45 received three examinations; 58 received two examinations; and 75 received only one examination. The sensitivity and specificity of CEUS was 90% and 93%, respectively, higher than abdominal US (80%, 86%), CT (71%, 92%), MRI (75%, 90%), and PET/CT (55%, 90%) (all values respective). The sensitivity, specificity, NPV, and PPV of the US combined with CEUS were 91%, 90%, 94%, and 85%, respectively. Although the specificity of CEUS + CT and CEUS + MRI were 100% and 92%, respectively, the sensitivity of CEUS + CT and CEUS + MRI were both only 67%.

CONCLUSIONS

The Abdominal US is not sufficiently accurate to confidently guide clinical practice, and CEUS showed better diagnostic performance than the other imaging modalities in differentiating XGC from GBC. The combination of abdominal CEUS and CT is helpful for differential diagnosis, as it indicates GBC with better specificity and PPV.

[Differential diagnosis of gallbladder abnormalities : Ultrasound, computed tomography, and magnetic resonance imaging]

CLINICAL ISSUE

Due to the high prevalence of clinically suspected cholecystitis or cholecystolithiasis the gallbladder is one of the organs examined the most by imaging.

STANDARD RADIOLOGICAL METHODS

In most clinical settings ultrasound is the primary imaging method because of its wide availability, speed and superior spatial resolution. In cases of ambiguous findings or potential complications computed tomography (CT) and magnetic resonance imaging (MRI) are used.

METHODICAL INNOVATIONS

When specific problems arise these imaging modalities may be enhanced by special techniques, e. g. contrast-enhanced ultrasound or dual-energy CT, and specific MRI sequences.

PERFORMANCE

Special variants of cholecystitis, such as xanthogranulomatous cholecystitis and adenomyomatosis, may pose a particularly difficult diagnostic problem as they may resemble other diseases. Sequelae of cholecystolithiasis, such as the Mirizzi syndrome and acute bowel obstruction, may complicate the imaging algorithm as the location and the symptoms shift. Cases of neoplastic diseases of gallbladder cancer and other malignancies require a broad spectrum of imaging modalities.

ACHIEVEMENTS

Although the gallbladder can easily be examined with ultrasound, some cases require a more thorough ultrasound examination. In some cases only a combination of multiple imaging modalities yield the diagnosis. Further developments regarding technical issues and the diagnostic algorithm can be expected.

PRACTICAL RECOMMENDATIONS

Ultrasound is the best first imaging modality. In cases of ambiguous findings or clinical complications CT or MRI are recommended.

[Value of ultrasonography in diagnosis of xanthogranulomatous cholecystitis]

OBJECTIVE

To assess the value of ultrasonography in differential diagnosis of xanthogranulomatous cholecystitis (XGC) and wall-thickening type of gallbladder cancer (GBC).

METHODS

The clinical features and sonographic finding of 31 patients with XGC and 36 patients with wall-thickening type of GBC were retrospectively reviewed. The diagnosis of all cases was confirmed by pathological examination, and the ultrasonographic manifestations of the thickening of the gallbladder wall, intramural hypoechoic nodules, gallbladder mucosa line, gallbladder stones, biliary dilatation and gallbladder-liver boundary were compared between two groups.

RESULTS

There were significant differences in the intramural hypoechoic nodules, the continuous gallbladder wall mucosal line and dilatation of bile duct between XGC and GBC groups (all P<0.05), while no statistically significant differences in the other sonographic features(all P>0.05). In the six positive sonographic features of the XGC patients, the intramural hypoechoic nodules and the continuous mucosa line of the gallbladder wall had highest accuracy in the diagnosis of XGC(64.2% and 65.7%).

CONCLUSIONS

Intramural hypoechoic nodule and the continuous mucosal line are characteristic sonographic features of XGC, which can be used for the diagnosis of XGC.

Xanthogranulomatous cholecystitis: diagnostic performance of US, CT, and MRI for differentiation from gallbladder carcinoma

OBJECTIVES

The purpose of this study is to evaluate the diagnostic performance of HRUS, CT, and MRI for differentiating xanthogranulomatous cholecystitis (XGC) from gallbladder (GB) cancer.

MATERIALS AND METHODS

Patients with surgically proven XGC (n = 40) and GB cancer (n = 44), who had undergone at least one HRUS (n = 43), CT (n = 82), or MRI (n = 34) examination between 2000 and 2012, were included. Two radiologists retrospectively graded the likelihood of XGC or GB cancer using a 5-point confidence scale; they also assessed the imaging features. Statistical analyses were performed using ROC, ANOVA, and Fisher's exact test.

RESULTS

Diagnostic performance of MRI was better than HRUS for differentiating XGC from GB cancer (AUCs = 0.867 and 0.911 vs. AUCs = 0.818 and 0.86). However, HRUS showed a better performance than CT (AUCs = 0.818 and 0.86 vs. AUCs = 0.806 and 0.84) with moderate to excellent agreement (κ = 0.48-0.83). Statistically common findings for XGC included non-focal thickening, smooth GB wall, presence of intramural nodules, type I enhancement of wall, transient hepatic attenuation difference, and continuity of mucosa (p < 0.05). Co-existence of gallstones (OR = 16.5), non-focal thickening (OR = 14.7), and collapsed lumen (OR = 13.0) on HRUS, and type I enhancement on CT (OR = 3.52) were independently associated with XGC (p < 0.05).

CONCLUSION

Although MRI showed a better performance than both HRUS and CT, HRUS showed a better performance than CT. The co-existence of gallstones, non-focal thickening, and collapsed lumen on HRUS was independently associated with XGC.

Xanthogranulomatous cholecystitis: What every radiologist should know

Xanthogranulomatous cholecystitis (XGC) is an uncommon variant of chronic cholecystitis characterized by xanthogranulomatous inflammation of the gallbladder. Intramural accumulation of lipid-laden macrophages and acute and chronic inflammatory cells is the hallmark of the disease. The xanthogranulomatous inflammation of the gallbladder can be very severe and can spill over to the neighbouring structures like liver, bowel and stomach resulting in dense adhesions, perforation, abscess formation, fistulous communication with adjacent bowel. Striking gallbladder wall thickening and dense local adhesions can be easily mistaken for carcinoma of the gallbladder, both intraoperatively as well as on preoperative imaging. Besides, cases of concomitant gallbladder carcinoma complicating XGC have also been reported in literature. So, we have done a review of the imaging features of XGC in order to better understand the entity as well as to increase the diagnostic yield of the disease summarizing the characteristic imaging findings and associations of XGC. Among other findings, presence of intramural hypodense nodules is considered diagnostic of this entity. However, in some cases, an imaging diagnosis of XGC is virtually impossible. Fine needle aspiration cytology might be handy in such patients. A preoperative counselling should include possibility of differential diagnosis of gallbladder cancer in not so characteristic cases.

Xanthogranulomatous cholecystitis mimicking gallbladder carcinoma: An analysis of 42 cases

AIM: To review and evaluate the diagnostic dilemma of xanthogranulomatous cholecystitis (XGC) clinically.

METHODS: From July 2008 to June 2014, a total of 142 cases of pathologically diagnosed XGC were reviewed at our hospital, among which 42 were misdiagnosed as gallbladder carcinoma (GBC) based on preoperative radiographs and/or intra-operative findings. The clinical characteristics, preoperative imaging, intra-operative findings, frozen section (FS) analysis and surgical procedure data of these patients were collected and analyzed.

RESULTS: The most common clinical syndrome in these 42 patients was chronic cholecystitis, followed by acute cholecystitis. Seven (17%) cases presented with mild jaundice without choledocholithiasis. Thirty-five (83%) cases presented with heterogeneous enhancement within thickened gallbladder walls on imaging, and 29 (69%) cases presented with abnormal enhancement in hepatic parenchyma neighboring the gallbladder, which indicated hepatic infiltration. Intra-operatively, adhesions to adjacent organs were observed in 40 (95.2%) cases, including the duodenum, colon and stomach. Thirty cases underwent FS analysis and the remainder did not. The accuracy rate of FS was 93%, and that of surgeon’s macroscopic diagnosis was 50%. Six cases were misidentified as GBC by surgeon’s macroscopic examination and underwent aggressive surgical treatment. No statistical difference was encountered in the incidence of postoperative complications between total cholecystectomy and subtotal cholecystectomy groups (21% vs 20%, P > 0.05).

CONCLUSION: Neither clinical manifestations and laboratory tests nor radiological methods provide a practical and effective standard in the differential diagnosis between XGC and GBC.

Xanthogranulomatous cholecystitis mimicking gallbladder cancer

Xanthogranulomatous cholecystitis (XGC) is a benign, uncommon variant of chronic cholecystitis characterised by focal or diffuse destructive inflammatory process of the gallbladder (GB). Macroscopically, it appears like yellowish tumour-like masses in the wall of the GB. This article reports on a 74-year-old woman with XGC mimicking GB cancer.

Differentiating xanthogranulomatous cholecystitis from wall-thickening type of gallbladder cancer: added value of diffusion-weighted MRI

AIM

To evaluate the benefit of diffusion-weighted imaging (DWI) in differentiating xanthogranulomatous cholecystitis from the wall-thickening type of gallbladder cancer.

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board. Fourteen patients with xanthogranulomatous cholecystitis and 19 patients with the wall-thickening type of gallbladder cancer were included. Qualitative (visual diffusion restriction compared to liver parenchyma) and quantitative [apparent diffusion coefficient (ADC)] analyses were performed. Conventional MRI findings including dynamic enhancement pattern between the two groups were also analysed. Two observers independently reviewed conventional magnetic resonance imaging (MRI) images and subsequently reviewed combined conventional MRI and DWI images. Pairwise comparison of the receiver operating characteristic (ROC) curves was used to compare diagnostic performances.

RESULTS

In conventional MRI findings, xanthogranulomatous cholecystitis showed significant continuity of enhancing mucosal line [79% (11/14) versus 26% (5/19), p = 0.003] and intramural T2-high signal intensity [64% (9/14) versus 21% (4/19), p = 0.012] compared to the wall-thickening type of gallbladder cancer. The enhancement pattern of gallbladder cancer compared to liver parenchyma showed earlier onset than that of xanthogranulomatous cholecystitis (p = 0.001). Diffusion restriction was more frequently seen in the wall-thickening type of gallbladder cancer (68%, 13/19) than in xanthogranulomatous cholecystitis (7%, 1/14; p < 0.001). The mean ADC value of xanthogranulomatous cholecystitis was higher than that of the wall-thickening type of gallbladder cancer with statistical significance (1.637 × 10(-3) mm(2)/s versus 1.076 × 10(-3) mm(2)/s, p = 0.005). Diagnostic performance [area under ROC curve (Az)] of both observers improved significantly after additional review of DWI; Az improved from 0.737 to 0.930 (p = 0.027) for observer 1 and from 0.675 to 0.938 (p = 0.008) for observer 2.

CONCLUSION

Addition of DWI to conventional MRI improves discrimination between xanthogranulomatous cholecystitis and the wall-thickening type of gallbladder cancer.

CT and MR features of xanthogranulomatous cholecystitis: an analysis of consecutive 49 cases

OBJECTIVE

To study the CT and MR features of xanthogranulomatous cholecystitis (XGC).

MATERIALS AND METHODS

49 patients had pathologically confirmed XGC. All patients underwent contrast enhanced CT, and 10 patients had additional plain MRI. The CT and MRI results were retrospectively analyzed.

RESULTS

On CT, all patients had thickening of gallbladder wall, with 87.8% cases showed diffuse thickening. 85.7% cases had intramural hypo-attenuated nodules in the thickened wall. Continuous mucosal line and luminal surface enhancement were noted in 79.6% and 85.7% cases, respectively. Gallbladder stones were seen in 69.4% patients. The coexistence of the above 5 CT features was seen in 40% cases, and 80% cases had the coexistence of ≥ 4 features. Diffused gallbladder wall thickening in XGC is more likely to have disrupted mucosal line, and XGC with disrupted mucosal line is more likely to be associated with liver infiltration. In 60% patients the inflammatory process extended beyond gallbladder, with the interface between gallbladder and liver and/or the surrounding fat blurred. 40% cases had an early enhancement of liver parenchyma. Infiltration to other surrounding tissues included bowel (n=3), stomach (n=2), and abdominal wall (n=1). On MR images, 7 of 9 intramural nodules in 7 subjects with T1-weighted dual echo MR images showed higher signal intensity on in-phase images than out-of-phase images.

CONCLUSION

Coexisting of diffuse gallbladder wall thickening, hypo-attenuated intramural nodules, continuous mucosal line, luminal surface enhancement, and gallbladder stone highly suggest XGC. XGC frequently infiltrate liver and surrounding fat. Chemical-shift MRI helps classifying intramural nodules in the gallbladder wall.