Analysis of enhancement pattern of flat gallbladder wall thickening on MDCT to differentiate gallbladder cancer from cholecystitis. AJR Am J Roentgenol. 2008;191:765-771. [PMID: 18716107 DOI: 10.2214/ajr.07.3331]

Contrast Enhanced CT Versus MRI for Accurate Diagnosis of Wall-thickening Type Gallbladder Cancer

Introduction

Diagnosis of wall-thickening type gallbladder cancer (GBC) is challenging. Computed tomography (CT) and magnetic resonance imaging (MRI) are commonly utilized to evaluate gallbladder wall thickening. However, there is a lack of data comparing the performance of CT and MRI for the detection of wall-thickening type GBC.

Aim

We aim to compare the diagnostic accuracy of CT and MRI in diagnosis of wall-thickening type GBC.

Materials and methods

This prospective study comprised consecutive patients suspected of wall-thickening type GBC who underwent preoperative contrast-enhanced CT and MRI. The final diagnosis was based on the histopathology of the resected gallbladder lesion. Two radiologists independently reviewed the characteristics of gallbladder wall thickening at CT and MRI. The association of CT and MRI findings with histological diagnosis and the interobserver agreement of CT and MRI findings were assessed.

Results

Thirty-three patients (malignancy, 13 and benign, 20) were included. None of the CT findings were significantly associated with GBC. However, at MRI, heterogeneous enhancement, indistinct interface with the liver, and diffusion restriction were significantly associated with malignancy (P = 0.006, <0.001, and 0.005, respectively), and intramural cysts were significantly associated with benign lesions (P = 0.012). For all MRI findings, the interobserver agreement was substantial to perfect (kappa = 0.697-1.000). At CT, the interobserver agreement was substantial to perfect (k = 0.631-1.000).

Conclusion

These findings suggest that MRI may be preferred over CT in patients with suspected wall thickening type GBC. However, larger multicenter studies must confirm our findings.

Should we suspect gallbladder cancer if which CT finding is observed in patients with localized gallbladder wall thickening?

PURPOSE

To identify high-risk computed tomography (CT) features for predicting gallbladder (GB) cancer in patients presenting with localized GB wall thickening.

METHODS

This retrospective analysis included 120 patients (mean age: 63.9 ± 10.0 years; 51 men) exhibiting localized GB wall thickening on CT scans obtained between January 2008 and May 2017. Two radiologists independently evaluated CT imaging features for predicting GB cancer. The diagnostic performance of significant imaging features and their combinations was evaluated. High-risk CT features ranked by accuracy were delineated for predicting GB cancer.

RESULTS

This study included 55 patients with GB cancer and 65 with benign GB conditions. The top-four most accurate CT imaging features for predicting GB cancer were identified: heterogeneously enhancing single layer or strongly enhancing thick inner layer; GB wall thickness > 6.5 mm; hyperenhancement on arterial phase; and absence of intramural small cystic lesions (accuracies of 90.0 %, 88.3 %, 85.0 %, and 85.0 %, respectively). The combination of any three high-risk features exhibited the highest accuracy (94.2 %). The presence of any high-risk feature yielded a sensitivity of 100 %, whereas that of all high-risk features indicated a specificity of 100 %.

CONCLUSION

CT imaging features, whether alone or in combination, could effectively and accurately predict GB cancer among patients with localized GB wall thickening. This finding holds significance in guiding decisions regarding further diagnostic tests and treatment planning.

Diagnostic performance of the gallbladder reporting and data system combined with color doppler flow imaging for gallbladder cancer in the Asian population

Purpose

Evaluating the performance of the Gallbladder Reporting and Data System (GB-RADS) combined with Color Doppler Flow Imaging (CDFI) for the diagnosis of gallbladder wall thickening disease in an Asian population.

Methods

In this study, the lesions were classified and the actual incidence rate of malignant tumors was calculated for each GB-RADS category, following the guidelines provided by GB-RADS. To evaluate the diagnostic performance of GB-RADS and GB-RADS combined with CDFI, we plotted Receiver Operator Characteristic (ROC) curves. The sensitivity (SE), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), and accuracy (AC) were also calculated. Inter-observer agreement (IRA) between the two observers was assessed using Kappa values.

Results

The incidence of malignancy risk for GB-RADS 2, 3, 4, and 5 was 9%, 12.5%, 72.2%, and 100%. The AUC for GB-RADS was 0.855 (95% CI: 0.800-0.900), with a sensitivity of 82.5%, a specificity of 84.6%, and an accuracy of 83.8%. The AUC of GB-RADS combined with CDFI was 0.965 (95% CI: 0.930-0.985), with a sensitivity of 96.2%, a specificity of 94.6%, and an accuracy of 95.2%. The AUC, sensitivity, specificity, and accuracy of GB-RADS combined with CDFI for diagnosing gallbladder malignancy were higher than those of GB-RADS alone, and the differences were statistically significant (all P < 0.05). The IRA was excellent between the two observers (Kappa = 0.870).

Conclusions

GB-RADS combined with CDFI demonstrated excellent diagnostic accuracy when it comes to distinguishing various diseases that caused gallbladder wall thickening in the Asian population, which has good clinical value and can improve the detection rate of malignant tumors in patients with gallbladder wall thickening.

Xanthogranulomatous cholecystitis in a patient with ulcerative colitis and primary sclerosing cholangitis: A case report

Chronic gallbladder disease due to xanthogranulomatous cholecystitis is uncommon, and its symptoms are generally vague. While there is no firm evidence to link xanthogranulomatous cholecystitis to primary sclerosing cholangitis or ulcerative colitis. The patient is a 41-year-old male with a history of ulcerative colitis, primary sclerosing cholangitis, and biliary stenting who complained of symptoms of anorexia, jaundice, and pruritus. In the initial ultrasound exam, there was evidence of intrahepatic and extra-hepatic bile duct dilation along with a significant and mass-like circumferential thickening of the gallbladder wall. Magnetic resonance cholangiopancreatography was performed for further evaluation, which indicated increased gallbladder wall thickness, containing multiple T2 hyper-signal nodules while the mucosal layer was intact. There was also a filling defect in the common bile duct's distal portion. These findings matched a xanthogranulomatous cholecystitis diagnosis and a possibly malignant lesion in the distal of the common bile duct. The patient ultimately had a cholecystectomy, and pathology findings confirmed the diagnosis of xanthogranulomatous cholecystitis. Biopsy specimens obtained from the distal of the common bile duct lesion were microscopically identified as intramucosal adenocarcinoma. In patients with a history of primary sclerosing cholangitis who present with nonspecific symptoms suggesting chronic gallbladder disease and radiologic evidence of circumferential gallbladder wall thickening containing intramural nodules and intact mucosa, xanthogranulomatous cholecystitis should be kept in mind.

Multiparametric MR imaging with diffusion-weighted, intravoxel incoherent motion, diffusion tensor, and dynamic contrast-enhanced perfusion sequences to assess gallbladder wall thickening: a prospective study based on surgical histopathology

OBJECTIVE

To investigate the diagnostic performance of a multiparametric magnetic resonance imaging (MRI) protocol comprising quantitative MRI (diffusion-weighted imaging (DWI), intravoxel incoherent motion (IVIM), diffusion tensor imaging (DTI), and dynamic contrast-enhanced (DCE) perfusion MRI) and conventional MRI in the characterization of gallbladder wall thickening (GWT).

METHODS

This prospective study comprised consecutive adults with GWT who underwent multiparametric MRI between July 2020 and April 2022. Two radiologists evaluated the MRI independently. The final diagnosis was based on surgical histopathology. The association of MRI parameters with malignant GWT was evaluated. The area under the curve (AUC) for the quantitative MRI parameters and diagnostic performance of conventional, and multiparametric MRI were compared. The interobserver agreement between two radiologists was calculated.

RESULTS

Thirty-five patients (mean age, 56 years, 23 females) with GWT (25 benign and ten malignant) were evaluated. The quantitative MRI parameters significantly associated with malignant GWT were apparent diffusion coefficient on DWI (p = 0.007) and mean diffusivity (MD) on DTI (p = 0.013), perfusion fraction (f) on IVIM (p = 0.033), time to peak enhancement (TTP, p = 0.008), and wash in rate (p = 0.049) on DCE-MRI. TTP had the highest AUC of 0.790, followed by MD (0.782) and f (0.742) (p = 0.213) for predicting malignant GWT. Multiparametric MRI had significantly higher sensitivity (90% vs. 80%, p = 0.045) than conventional MRI for diagnosing malignant GWT. The two radiologists' reading had substantial to near-perfect agreement (kappa = 0.639-1) and moderate to strong correlation (interclass correlation coefficient = 0.5-0.88).

CONCLUSION

Multiparametric protocol incorporating advanced sequences improved the diagnostic performance of MRI for differentiating benign and malignant GWT.

KEY POINTS

• Multiparametric MRI had 90% sensitivity and 88% specificity for diagnosing malignant GWT, compared to 80% sensitivity and 88% specificity for conventional CE-MRI. • Among the quantitative MRI parameters, TTP (perfusion-MRI) had the highest AUC of 0.790, followed by MD (0.782) and IVIM-f (0.742). • For most quantitative MRI parameters, there was moderate to strong agreement (ICC = 0.5-0.88).

Contrast-Enhanced CT and Ultrasonography Features of Intracholecystic Papillary Neoplasm with or without associated Invasive Carcinoma

OBJECTIVE

To assess the contrast-enhanced CT and ultrasonography (US) findings of intracholecystic papillary neoplasm (ICPN) and determine the imaging features predicting ICPN associated with invasive carcinoma (ICPN-IC).

MATERIALS AND METHODS

In this retrospective study, we enrolled 119 consecutive patients, including 60 male and 59 female, with a mean age ± standard deviation of 63.3 ± 12.1 years, who had pathologically confirmed ICPN (low-grade dysplasia [DP] = 34, high-grade DP = 35, IC = 50) and underwent preoperative CT or US. Two radiologists independently assessed the CT and US findings, focusing on wall and polypoid lesion characteristics. The likelihood of ICPN-IC was graded on a 5-point scale. Univariable and multivariable logistic regression analyses were performed to identify significant predictors of ICPN-IC separately for wall and polypoid lesion findings. The performances of CT and US in distinguishing ICPN-IC from ICPN with DP (ICPN-DP) was evaluated using the area under the receiver operating characteristic curve (AUC).

RESULTS

For wall characteristics, the maximum wall thickness (adjusted odds ratio [aOR] = 1.4; 95% confidence interval [CI]: 1.1-1.9) and mucosal discontinuity (aOR = 5.6; 95% CI: 1.3-23.4) on CT were independently associated with ICPN-IC. Among 119 ICPNs, 110 (92.4%) showed polypoid lesions. Regarding polypoid lesion findings, multiplicity (aOR = 4.0; 95% CI: 1.6-10.4), lesion base wall thickening (aOR = 6.0; 95% CI: 2.3-15.8) on CT, and polyp size (aOR = 1.1; 95% CI: 1.0-1.2) on US were independently associated with ICPN-IC. CT showed a higher diagnostic performance than US in predicting ICPN-IC (AUC = 0.793 vs. 0.676; p = 0.002).

CONCLUSION

ICPN showed polypoid lesions and/or wall thickening on CT or US. A thick wall, multiplicity, presence of wall thickening in the polypoid lesion base, and large polyp size are imaging findings independently associated with invasive cancer and may be useful for differentiating ICPN-IC from ICPN-DP.

A Case of Early-Stage Gallbladder Cancer, Positive for ALDH1A1, Which Arose from Adenomyomatosis of the Gallbladder

Adenomyomatosis (ADM) of the gallbladder is a condition characterized by the proliferation of Rokitansky–Aschoff sinus (RAS), in which the epithelium of the gallbladder extends into the muscular layer, causing a thickening of the gallbladder wall. Although ADM is generally considered not to be a precancerous lesion of gallbladder cancer, there are some reports of cases of gallbladder cancer from ADM. Therefore, the relationship between ADM and gallbladder cancer remains controversial. We herein report a case of early-stage gallbladder cancer, BilIN3 (high grade), arising from ADM that was positive for ALDH1A1, an important marker of stem cells and cancer stem cells.

Differentiating benign from malignant gallbladder wall thickening in non-contrast MRI imaging: Preliminary study of a combined diagnostic indicator

To synthetically evaluate the diagnostic accuracy of image features for differentiating benign from malignant gallbladder wall thickening disease with non-contrast MRI and establish the optimal diagnostic indicator. A total of 23 patients with wall thickening type gallbladder carcinoma and 61 patients with benign wall thickening disease were included. The diagnostic performance of six image features including the layered pattern on T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) images, T2WI signal intensity, papillary growth, the apparent diffusion coefficient (ADC) value, and the lesion to liver parenchyma ratio (LLR) of gallbladder were evaluated and compared. The receiver operating characteristic (ROC) curve and binary logistic regression analysis were used to construct the optimally combined indicator. All six indicators showed high diagnostic accuracy. The layered pattern on DWI and LLR had the highest area under the curve (AUC) value (0.904), followed by the layered pattern on T2WI (0.883), T2WI signal intensity (0.859), ADC value (0.836), and papillary growth (0.796). There was no statistically significant difference in the AUC among indicators for pairwise comparisons. A combination of layered patterns on DWI and papillary growth was shown to be the optimal indicator by binary logistic regression analysis. The AUC value of the combination (0.972) was higher than the layered pattern on DWI (0.904) and papillary growth (0.796) (P < .001). Non-contrast MRI provides several reliable indicators for differentiating benign from malignant gallbladder thickening disease. The combination of layered patterns on DWI and papillary growth is the optimal indicator.

Computed diffusion-weighted magnetic resonance imaging with high b-values in the diagnosis of gallbladder lesions

PURPOSE

The diagnosis of gallbladder lesions remains challenging. The efficacy of computed diffusion-weighted imaging (DWI) with high b-values and apparent diffusion coefficient (ADC) for the diagnosis of gallbladder cancer remains unknown. We aimed to investigate the usefulness of computed DWI with high b-values and the combination of computed DWI and ADC in differentiating malignant and benign gallbladder lesions.

METHODS

Sixty patients (comprising 30 malignant and 30 benign lesions) who underwent magnetic resonance imaging for gallbladder lesions were included in this retrospective study. Qualitative evaluations were performed using conventional DWI with b1000, computed DWI with b1500, b1000 DWI/ADC, and computed b1500 DWI/ADC, and their diagnostic performances were compared.

RESULTS

The sensitivity, specificity, and accuracy of computed b1500 DWI/ADC were 90% (27/30), 80% (24/30), and 85% (51/60), respectively. The accuracy of computed b1500 DWI/ADC was higher than that of conventional b1000 DWI (52%, 31/60, p < 0.001), computed b1500 DWI (72%, 43/60, p = 0.008), and b1000 DWI/ADC (78%, 47/60, p = 0.125). The specificity of computed b1500 DWI/ADC was also higher than that of conventional b1000 DWI (7%, 2/30, p < 0.001), computed b1500 DWI (47%, 14/30, p = 0.002), and b1000 DWI/ADC (67%, 20/30, p = 0.125). No significant difference was observed in the sensitivity between the groups.

CONCLUSION

This study shows that computed DWI with high b-values combined with ADC can improve diagnostic performance when differentiating malignant and benign gallbladder lesions. Computed diffusion-weighted magnetic resonance imaging with high b-values in the diagnosis of gallbladder lesions. *Computed DWI with b1500 combined with ADC can improve diagnostic performance when differentiating gallbladder lesions compared with conventional methods (b1000 DWI).

Multimodality Imaging of Cholecystectomy Complications

Cholecystectomy is one of the most common surgeries performed in the United States. Although complications are uncommon, the high incidence of this surgery means that a radiologist will likely encounter these complications in practice. Complications may arise in the immediate postoperative period or can be delayed for weeks, months, or years after surgery. Vague and nonspecific symptoms make clinical diagnosis challenging. As a result, multimodality imaging is important in postoperative evaluation. US and multidetector CT are the usual first-line imaging modalities. Hepatobiliary scintigraphy, SPECT/CT, and MRI with conventional or gadoxetate hepatobiliary contrast material are important and complementary modalities that are used for workup. The authors begin with a brief discussion of surgical technique and expected postoperative findings and then describe complications organized into four groups: (a) biliary complications, (b) stone-related complications, (c) iatrogenic complications, and (d) gallbladder complications. Biliary complications include bile leaks and bilomas, acute biliary obstruction, and biliary stricture. Stone-related complications include retained and recurrent stones and spillage of stones into the peritoneum. Iatrogenic complications include hemorrhage, vasculobiliary injury, arterial pseudoaneurysms, duodenal injury, and migration of clips. Gallbladder complications include recurrent cholecystitis after subtotal reconstituting cholecystectomy and unexpected gallbladder cancer. An invited commentary by Mullens and Ibrahim is available online. Online supplemental material is available for this article. ^©RSNA, 2022.

Role of dual energy computed tomography in evaluation of suspected wall thickening type of gallbladder cancer

Introduction

Accurate characterization of gallbladder wall thickening is of paramount importance. This study evaluated the role of dual-energy computed tomography (DECT) in the evaluation of gallbladder wall thickening.

Material and methods

Seven consecutive patients (mean age 52.3 years, 5 males) with suspected wall thickening type of gallbladder cancer (GBC) who underwent DECT between August 2020 and March 2021 were included. Independent radiologists blinded to the final diagnosis reviewed the iodine maps, 80 keV, and 140 keV images separately. The final diagnosis was based on histopathology or cytology.

Results

Two patients had xanthogranulomatous cholecystitis and 5 had GBC. Asymmetrical mural thickening was identified in six patients on iodine maps and five patients at 80 keV. Non-layered mural thickening was seen in all patients on iodine maps, 80 keV, and 140 keV. Iodine maps identified heterogeneous enhancement in all patients.

Conclusions

These preliminary results suggest that DECT has the potential to characterize gallbladder wall thickening.

Contrast enhanced ultrasound versus multiphasic contrast enhanced computed tomography in evaluation of gallbladder lesions

AIM

To compare the diagnostic performance of contrast enhanced ultrasound (CEUS) and multiphasic contrast enhanced computed tomography (CECT) in differentiating benign and malignant gallbladder (GB) lesions.

METHODS

This prospective ethical review board approved study comprised consecutive patients with GB lesions who underwent CEUS and multiphasic CECT at a tertiary care referral center. The enhancement patterns at CEUS and CT were compared. The quantitative CEUS parameters including arrival time (AT), AT in liver, time to peak enhancement, and washout time (WT) were assessed. The diagnostic performance of CEUS and CT features was calculated using receiver operating characteristic analysis. A subgroup analysis was performed for patients with GB wall thickening. Multivariate analysis was performed to identify features significantly associated with malignancy.

RESULTS

Over the study period, 30 patients (mean age, 52.8 ± 12.2 years, 17 females) with GB lesions were evaluated. Benign and malignant diseases were present in 13 and 17 patients, respectively. There was excellent agreement between CEUS and CT findings. Among the quantitative CEUS features, only WT was significantly associated with malignancy in the overall group (p < 0.001) and wall thickening subgroup (p = 0.007). WT within 53.5 s and 51.5 s had sensitivity of 88.2% and 81.8% and specificity of 84.5% and 100% in diagnosing malignant lesions in the overall group (AUC 0.900) and the wall thickening subgroup (area under curve, AUC 0.927), respectively. At multivariate analysis, features that were significantly associated with malignant lesions in the overall group were disruption of GB wall (CEUS), intralesional non-enhancing areas (CEUS), liver involvement (CEUS or CT), and arterial phase hyperenhancement (CT) in the overall group and disruption of GB wall (CEUS), WT (CEUS), and liver involvement (CEUS or CT) in the wall thickening subgroup.

CONCLUSION

CEUS is a useful adjunct to CT in evaluation of GB lesions. Its utilization in patients with GB wall thickening may improve detection of malignancy.

Association of Microbial Dysbiosis with Gallbladder Diseases Identified by Bile Microbiome Profiling

BACKGROUND

Cholecystitis is an important risk factor for gallbladder cancer, but the bile microbiome and its association with gallbladder disease has not been investigated fully. We aimed to analyze the bile microbiome in normal conditions, chronic cholecystitis, and gallbladder cancer, and to identify candidate bacteria that play an important role in gallbladder carcinogenesis.

METHODS

We performed metagenome sequencing on bile samples of 10 healthy individuals, 10 patients with chronic cholecystitis, and 5 patients with gallbladder cancer, and compared the clinical, radiological, and pathological characteristics of the participants.

RESULTS

No significant bacterial signal was identified in the normal bile. The predominant dysbiotic bacteria in both chronic cholecystitis and gallbladder cancer were those belonging to the Enterobacteriaceae family. Klebsiella increased significantly in the order of normal, chronic cholecystitis, and gallbladder cancer. Patients with chronic cholecystitis and dysbiotic microbiome patterns had larger gallstones and showed marked epithelial atypia, which are considered as precancerous conditions.

CONCLUSION

We investigated the bile microbiome in normal, chronic cholecystitis, and gallbladder cancer. We suggest possible roles of Enterobacteriaceae, including Klebsiella, in gallbladder carcinogenesis. Our findings reveal a possible link between a dysbiotic bile microbiome and the development of chronic calculous cholecystitis and gallbladder cancer.

Current update on gallbladder carcinoma

Gallbladder (GB) carcinoma is a relatively rare malignancy and is associated with poor prognosis. Numerous risk factors have been associated with the development of GB carcinoma. GB carcinomas may present as mass lesions replacing the GB, focal or diffuse thickening of the GB wall, and intraluminal mass in the GB. Various benign conditions can mimic GB carcinoma. This article reviews the epidemiology, pathology, clinical findings, imaging features, and management of GB carcinomas.

Diagnostic performance of preoperative CT in differentiating between benign and malignant origin of suspicious gallbladder lesions

PURPOSE

To determine diagnostic performance of preoperative CT in differentiating between benign and malignant suspicious gallbladder lesions and to develop a preoperative risk score.

METHOD

All patients referred between January 2007 and September 2018 for suspicion of gallbladder cancer (GBC) or incidentally found GBC were retrospectively analyzed. Patients were excluded when preoperative CT or histopathologic examination was lacking. Two radiologists, blinded to histopathology results, independently reviewed CT images to differentiate benign disease from GBC. Multivariable analysis and internal validation were used to develop a risk score for GBC. Model discrimination, calibration, and diagnostic performance were assessed.

RESULTS

In total, 118 patients with 39 malignant (33 %) and 79 benign (67 %) lesions were included. Sensitivity of CT for diagnosing GBC was 90 % (95 % confidence interval [CI]: 76-97). Specificity rates were 61 % (95 % CI: 49-72) and 59 % (95 % CI: 48-70). Three predictors of GBC (irregular lesion aspect, absence of fat stranding, and locoregional lymphadenopathy) were included in the risk score ranging from -1 to 4. Adequate performance was found (AUC: 0.79, calibration slope: 0.89). In patients allocated >0 points, the model showed higher performance in excluding GBC than the radiologists (sensitivity 92 % [95 % CI: 79-98]). Moreover, when allocated >3 points, the risk score was superior in diagnosing GBC (specificity 99 % [95 % CI: 93-100]).

CONCLUSIONS

Sensitivity rates of CT for differentiation between benign and malignant gallbladder lesions are high, however specificity rates are relatively low. The proposed risk score may facilitate differentiation between benign and malignant suspicious gallbladder lesions.

Imaging-based algorithmic approach to gallbladder wall thickening

Gallbladder (GB) wall thickening is a frequent finding caused by a spectrum of conditions. It is observed in many extracholecystic as well as intrinsic GB conditions. GB wall thickening can either be diffuse or focal. Diffuse wall thickening is a secondary occurrence in both extrinsic and intrinsic pathologies of GB, whereas, focal wall thickening is mostly associated with intrinsic GB pathologies. In the absence of specific clinical features, accurate etiological diagnosis can be challenging. The survival rate in GB carcinoma (GBC) can be improved if it is diagnosed at an early stage, especially when the tumor is confined to the wall. The pattern of wall thickening in GBC is often confused with benign diseases, especially chronic cholecystitis, xanthogranulomatous cholecystitis, and adenomyomatosis. Early recognition and differentiation of these conditions can improve the prognosis. In this minireview, the authors describe the patterns of abnormalities on various imaging modalities (conventional as well as advanced) for the diagnosis of GB wall thickening. This paper also illustrates an algorithmic approach for the etiological diagnosis of GB wall thickening and suggests a formatted reporting for GB wall abnormalities.

Examination of Prognostic Factors Affecting Long-Term Survival of Patients with Stage 3/4 Gallbladder Cancer without Distant Metastasis

In advanced gallbladder cancer (GBC) radical resection, if multiple prognostic factors are present, the outcome may be poor; however, the details remain unclear. To investigate the poor prognostic factors affecting long-term surgical outcome, we examined 157 cases of resected stage 3/4 GBC without distant metastasis between 1985 and 2017. Poor prognostic factors for overall survival and treatment outcomes of a number of predictable preoperative poor prognostic factors were evaluated. The surgical mortality was 4.5%. In multivariate analysis, blood loss, poor histology, liver invasion, and ≥4 regional lymph node metastases (LNMs) were independent prognostic factors for poor surgical outcomes; invasion of the left margin or the entire area of the hepatoduodenal ligament and a Clavien–Dindo classification ≥3 were marginal factors. The analysis identified outcomes of patients with factors that could be predicted preoperatively, such as liver invasion ≥5 mm, invasion of the left margin or the entire area of the hepatoduodenal ligament, and ≥4 regional LNMs. Thus, the five-year overall survival was 54% for zero factors, 34% for one factor, and 4% for two factors (p < 0.05). A poor surgical outcome was likely when two or more factors were predicted preoperatively; therefore, new treatment strategies are required for such patients.

Incidentally detected focal fundal gallbladder wall thickening: Differentiation contrast enhanced ultrasound features with high-resolution linear transducers

AIM

To investigate the value of contrast enhanced ultrasound with high resolution linear transducers (HF-CEUS) for differential diagnosis of focal fundal gallbladder (GB) wall thickening.

METHODS

A total of 32 patients with incidentally detected focal fundal GB wall thickening were included. After conventional B mode ultrasound (BMUS) examinations, HF-CEUS were performed with a 7.5-12 MHz 9L4 linear transducer (S2000 HELX OXANA unit, Siemens). Two radiologists independently reviewed the HF-CEUS enhancement patterns to determine the differential features between malignancy and benignity with a five-point confidence scale. The diagnostic accuracy of BMUS and HF-CEUS for GB wall thickening was compared. The final gold standard was surgery with histological examination.

RESULTS

Final diagnoses included GB adenocarcinoma (n = 16), adenomyomatosis (n = 12), Xanthogranulomatous (n = 2) and cholecystitis (n = 2). HF-CEUS features associated with GB adenocarcinoma including arterial phase inhomogeneous hyperenhancement, venous phase hypoenhancement and disruption of GB wall layer structure (P < 0.05). Two small (5 mm) liver metastasis were confirmed by HF-CEUS during the late phase liver sweep as hypoenhanced lesions. Nonenhanced Rokitansky-Aschoff sinuses were clearly observed in 83.3% focal adenomyomatosis. Overall sensitivity, specificity and accuracy for differentiation between malignant and benign focal fundal GB wall thickening of HF-CEUS and BMUS were 84.3% vs 53.1%, 90.6% vs 59.3% and 87.5% vs 56.2% (P < 0.005).

CONCLUSIONS

CEUS performed with high frequency linear transducers could be a useful alternative in the differential diagnosis of focal fundal GB wall thickening on conventional ultrasound.

Chronic gallbladder wall thickening: Is it always malignancy?

Gallbladder wall thickening, associated with features like perforation, fistula formation and invasion of adjacent organs, is often assumed to be malignant. Xanthogranulomatous cholecystitis (XGC) causes gallbladder wall thickening with similar aggressive features and closely mimics gallbladder carcinoma clinically, radiologically and surgically. Differentiating between these two is crucial for management as misdiagnosis of gallbladder cancer can lead to unnecessary radical surgery. We report a case of chronic gallbladder wall thickening, initially suspected to be malignant, but subsequently diagnosed as XGC.

Benign gallbladder diseases: Imaging techniques and tips for differentiating with malignant gallbladder diseases

Benign gallbladder diseases usually present with intraluminal lesions and localized or diffuse wall thickening. Intraluminal lesions of the gallbladder include gallstones, cholesterol polyps, adenomas, or sludge and polypoid type of gallbladder cancer must subsequently be excluded. Polyp size, stalk width, and enhancement intensity on contrast-enhanced ultrasound and degree of diffusion restriction may help differentiate cholesterol polyps and adenomas from gallbladder cancer. Localized gallbladder wall thickening is largely due to segmental or focal gallbladder adenomyomatosis, although infiltrative cancer may present similarly. Identification of Rokitansky-Aschoff sinuses is pivotal in diagnosing adenomyomatosis. The layered pattern, degree of enhancement, and integrity of the wall are imaging clues that help discriminate innocuous thickening from gallbladder cancer. High-resolution ultrasound is especially useful for analyzing the layering of gallbladder wall. A diffusely thickened wall is frequently seen in inflammatory processes of the gallbladder. Nevertheless, it is important to check for coexistent cancer in instances of acute cholecystitis. Ultrasound used alone is limited in evaluating complicated cholecystitis and often requires complementary computed tomography. In chronic cholecystitis, preservation of a two-layered wall and weak wall enhancement are diagnostic clues for excluding malignancy. Magnetic resonance imaging in conjunction with diffusion-weighted imaging helps to differentiate xathogranulomatous cholecystitis from gallbladder cancer by identifying the presence of fat and degree of diffusion restriction. Such distinctions require a familiarity with typical imaging features of various gallbladder diseases and an understanding of the roles that assorted imaging modalities play in gallbladder evaluations.

Evaluation of gallbladder wall thickening: a multimodality imaging approach

INTRODUCTION

Gallbladder (GB) wall thickening is a relatively common finding on imaging. While there are clear recommendations for the management of gallstones, GB wall thickening presents a significant challenge. Despite advances in radiological as well as endoscopic techniques, the ability to characterize GB wall thickening is still limited.

AREAS COVERED

This review summarizes the currently available literature on various imaging investigations to characterize GB wall thickening. This review also summarizes the differences between benign and malignant GB wall thickening based on available imaging modalities. Transabdominal ultrasonography is the first-line investigation for evaluation of GB wall thickening. However, further characterization requires additional imaging tests. Magnetic resonance imaging (MRI) with the use of gadolinium and diffusion-weighted sequence is the preferred modality for GB wall characterization.

EXPERT OPINION

The accurate characterization of GB wall thickening is a challenging task. The available imaging criteria allow differentiation of benign and malignant GB wall thickening with moderate accuracy. The advanced imaging techniques, including contrast enhanced ultrasound, contrast-enhanced endoscopic ultrasound, and shear wave elastography, continue to evolve. There is a need for a well-designed reporting system for GB wall thickening to ensure uniformity of reporting of imaging tests, especially in regions with a high prevalence of GB cancer.

Gallbladder Cancer: Imaging Appearance and Pitfalls in Diagnosis [Formula: see text]

Gallbladder cancer is an uncommon malignancy with an overall poor prognosis. The clinical and imaging presentation of gallbladder cancer often overlaps with benign disease, making diagnosis difficult. Gallbladder cancer is most easily diagnosed on imaging when it presents as a mass replacing the gallbladder. At this stage, the prognosis is usually poor. Recognizing the features of gallbladder cancer early in the disease can enable complete resection and improve prognosis. Recognition of the patterns of wall enhancement on computed tomography can help differentiate gallbladder cancer from benign disease. Gallbladder wall thickening without pericholecystic fluid presenting in an older patient with raised alkaline phosphatase should raise concern regarding gallbladder cancer. Gallbladder polyps in high-risk individuals need close surveillance or surgery as per guidelines. Small gallbladder cancers in the neck can present as biliary dilatation or cholecystitis, and careful examination of this area is needed to assess for lesion. The imaging appearance of gallbladder cancer is reviewed and supported by local institutional data. Features that differentiate it from its common mimics enabling earlier diagnosis are described.

Radio-pathological Correlation of 18F-FDG PET in Characterizing Gallbladder Wall Thickening

AIM

Thick-walled gallbladder is difficult to characterize on conventional imaging. 18F-FDG PET was used to differentiate benign and malignant wall thickness and compared with histopathology.

METHODS

Thirty patients with gallbladder (GB) wall thickening (focal > 4 mm and diffuse > 7 mm), underwents uspected on  ultrasound, or CT scan, and underwent 18F-FDG PET. Histopathology of the specimen was compared with imaging findings.

RESULTS

The mean age was 48.22 ± 31.33 years with a M:F 1:4 ratio. Twenty patients had diffuse and 10 had focal thickening. On 18F-FDG PET, lesion was benign in 12, malignant in 13, and indeterminate in 5. Histopathology was malignancy in 12; benign in 18-chronic cholecystitis in 11, xanthogranulomatous in 4, IgG4 related in 2, and polyp in 1. The mean GB wall thickness was 7.79 ± 3.59 mm (10.34 malignant and 6.10 in benign, p = 0.001). At a cutoff of 8.5 mm, the sensitivity and specificity of detecting malignancy was 94% and 67%. The mean SUV uptake was 7.46 (benign 4.51, malignant 14.26, p = 0.0102). At a cutoff of 5.95, the sensitivity and specificity of detecting malignancy was 92% and 79%. For 18F-FDG PET, overall sensitivity was 91%, specificity 79%, PPV 77%, NPV 92%, and diagnostic accuracy was 84%.

CONCLUSION

18F-FDG PET is a reliable method of differentiation between benign and malignant thickening of the gallbladder particularly when wall thickness and SUV value is taken into account.

Chronic inflammation-related radiological findings of gallbladder adenomyomatosis

PURPOSE

This study aimed to assess radiological findings of adenomyomatosis advancing to chronic inflammation to differentiate between adenomyomatosis with and without chronic inflammation.

MATERIALS AND METHODS

We retrospectively identified 79 patients with pathologically proven adenomyomatosis without (n = 10) or with chronic inflammation (n = 69), who underwent computed tomography (CT) and magnetic resonance imaging (MRI) followed by surgery. MRI analysis included evaluation of GB wall-thickening type, presence and location of intramural cysts, and presence of stones. CT analysis included GB wall-thickening type only. Multivariate logistic regression analysis was used to identify the image-based findings of adenomyomatosis associated with chronic inflammation.

RESULTS

On univariate analysis, MRI-based GB wall-thickening type and presence of stones, and CT-based GB wall-thickening type were significantly different between adenomyomatosis with and without chronic inflammation. On multivariate analysis, only the absence of stones was identified as a significant predictor of adenomyomatosis without chronic inflammation (odds ratio 5.58; 95% confidence interval 1.20-26.01; p = 0.029). There was no significant difference in other MRI- and CT-based findings between adenomyomatosis with and without chronic inflammation.

CONCLUSION

In patients with adenomyomatosis, the presence of stones was independently associated with chronic inflammation.

Utility of Contrast-Enhanced Ultrasound in Differentiation between Benign Mural Lesions and Adenocarcinoma of Gallbladder

Background

Mural lesions of gallbladder on ultrasound (US) are often difficult to characterize as benign or malignant.

Purpose

The aim of the study was to evaluate the role of contrast-enhanced US (CEUS) in characterization of gallbladder (GB) wall lesions and making distinction between benign wall thickening and GB adenocarcinoma, utilizing both quantitative and qualitative parameters.

Methods

A total of 26 patients with GB wall lesions detected on sonography underwent CEUS. Lesions were evaluated on the basis of morphological imaging features, enhancement pattern, dynamic real-time contrast uptake, and intralesional vascularity.

Results

Overall, 19 patients had final diagnosis of GB adenocarcinoma, whereas seven patients had benign etiology. CEUS has enabled the differentiation of nonenhancing tumefactive sludge from enhancing mural lesions, thus improving the accuracy of morphological assessment of lesions. The intactness of outer wall was better assessed on CEUS. The dynamic postcontrast assessment showed that carcinoma showed early washout of contrast compared to benign thickening (P = 0.002). Nonlayered mural enhancement or thick enhancing inner layer with nonenhancing thin outer layer was associated with adenocarcinoma. The classification of intralesional vascularity on CEUS was not helpful in distinguishing benign lesions and adenocarcinoma.

Conclusion

CEUS can increase the diagnostic confidence in differentiation between benign mural lesions and adenocarcinoma of GB.

Development and Validation of a Nomogram for Early Detection of Malignant Gallbladder Lesions

OBJECTIVES

Preoperative decision-making for differentiating malignant from benign lesions in the gallbladder remains challenging. We aimed to create a diagnostic nomogram to identify gallbladder cancer (GBC), especially for incidental GBC (IGBC), before surgical resection.

METHODS

A total of 587 consecutive patients with pathologically confirmed gallbladder lesions from a hospital were randomly assigned to a training cohort (70%) and an internal validation cohort (30%), with 287 patients from other centers as an external validation cohort. Radiological features were developed by the least absolute shrinkage and selection operator logistic regression model. Significant radiological features and independent clinical factors, identified by multivariate analyses, were used to construct a nomogram.

RESULTS

A diagnostic nomogram was established by age, CA19.9, and 6 radiological features. The values of area under the curve in the internal and external validation cohorts were up to 0.91 and 0.89, respectively. The calibration curves for probability of GBC showed optimal agreement between nomogram prediction and actual observation. Compared with previous methods, it demonstrated superior sensitivity (91.5%) and accuracy (85.1%) in the diagnosis of GBC. The accuracy using the nomogram was significantly higher in GBC groups compared with that by radiologists in the training cohort (P < 0.001) and similarly in each cohort. Notably, most of the IGBC, which were misdiagnosed as benign lesions, were successfully identified using this nomogram.

DISCUSSION

A novel nomogram provides a powerful tool for detecting the presence of cancer in gallbladder masses, with an increase in accuracy and sensitivity. It demonstrates an unprecedented potential for IGBC identification.

Incidentally Detected Focal Fundal Gallbladder Wall Thickening at Contrast-Enhanced Computed Tomography: Prevalence and Computed Tomography Features of Malignancy

OBJECTIVE

The aim of this study was to determine the prevalence and computed tomography (CT) features of malignancy in incidental focal fundal gallbladder wall thickening.

METHODS

Patients with incidental focal fundal gallbladder wall thickening on CT were included if they had an ultrasound or magnetic resonance imaging diagnostic of the etiology (n = 19), stability on CT for 1 year (n = 84), or pathological correlation (n = 13). Morphologies were classified as type 1 (nodular/pinched intramural low attenuation), type 2 (intramural low attenuation), type 3 (homogeneous enhancement), type 4 (nodular/pinched homogeneous enhancement), type 5 (intramural cystic spaces), or type 6 (hyperenhancing/heterogeneous enhancement).

RESULTS

One hundred sixteen patients had the following morphologies: type 1 (n = 57), type 2 (n = 10), type 3 (n = 6), type 4 (n = 19), type 5 (n = 14), and type 6 (n = 10). Four cases (3.4%; 95% confidence interval, 0.9%-8.6%) of malignancy were identified (type 6 in 3 and type 3 in 1).

CONCLUSIONS

Incidental focal fundal gallbladder wall thickening is usually benign. Computed tomography features help distinguish benign from malignant etiologies.

Cross-sectional Imaging of Gallbladder Carcinoma: An Update

Gallbladder Carcinoma (GBCA) is the most common biliary tract malignancy. As the disease is often diagnosed clinically in an advanced stage, the survival rates are dismal. Imaging studies allow for an early diagnosis of malignancy, though the findings may be indistinguishable from non-malignant disease processes affecting the gallbladder. Attempts have been made to make a specific diagnosis of GBCA at an early stage on imaging studies. Ultrasonography (US) is the most commonly employed technique for gallbladder evaluation. Gallbladder wall thickening is the most common finding of early GBCA and in this context, US is non-specific. Recently, contrast enhanced ultrasound has been shown to be effective in differentiating benign from malignant disease. Multidetector computed tomography represents the most robust imaging technique in evaluation of GBCA. It provides relatively sensitive evaluation of mural thickening, though it is not entirely specific and issues in differentiating GBCA from xanthogranulomatous cholecystitis do arise. Due to its superior soft tissue resolution, Magnetic Resonance Imaging (MRI) provides excellent delineation of gallbladder and biliary tree involvement. When coupled with functional MRI techniques, such as diffusion-weighted and perfusion imaging, it provides a useful problem solving tool for interrogating the malignant potential of nonspecific gallbladder lesions and detection of metastases. Positron emission tomography has a role in detection of distant metastases and following patients following treatment for malignancy. We review the current role of various imaging modalities in evaluating patients with GBCA.

Usefulness of noncontrast MRI in differentiation between gallbladder carcinoma and benign conditions manifesting as focal mild wall thickening

BACKGROUND

Magnetic resonance imaging (MRI) is a reliable imaging tool for evaluating gallbladder carcinoma, but it is costly and time-consuming.

PURPOSE

To compare noncontrast MRI with multidetector row CT (MDCT) and gadoxetic acid-enhanced whole MRI in distinguishing gallbladder carcinoma from benign disease.

MATERIALS AND METHODS

101 patients (36 with gallbladder carcinoma and 65 with benign disease) with mild focal gallbladder wall thickening were included. Two radiologists reviewed the MDCT and MRI to determine the differential features between malignancy and benignity. Then, the diagnostic performance of MDCT and MRI (T1-, T2- and diffusion-weighted images) with and without gadoxetic acid enhancement in the diagnosis of gallbladder carcinoma was evaluated.

RESULTS

The benign group more often showed T2 necklace sign or T2 hyperintensity within the thickened wall (P < 0.0001) and T1 hyperintensity within the wall or gallbladder lumen (P = 0.0002). Meanwhile, malignancy more frequently showed T2 moderate hyperintensity of the thickened wall, papillary appearance, and diffusion restriction (all P < 0.0001). There were significant differences in sensitivity (79.2% vs 98.6% for observer 1; 84.7% vs 100% for observer 2) and specificity (80.7% vs 96.9%; 79.2% vs 95.4%) between the MDCT and noncontrast MRI (P < 0.05). We found similar diagnostic values between the noncontrast MRI and whole MRI (P = 0.479-1.000) for both observers.

CONCLUSION

Noncontrast MRI could be a useful alternative to gadoxetic acid-enhanced MRI in the diagnosis of gallbladder carcinoma that presents as mild gallbladder wall thickening on MDCT.

Comet tail artifact on ultrasonography: is it a reliable finding of benign gallbladder diseases?

Purpose

The aim of this study was to evaluate whether the comet tail artifact on ultrasonography can be used to reliably diagnose benign gallbladder diseases.

Methods

This retrospective study reviewed the clinical findings, imaging findings, preoperative ultrasonographic diagnoses, and pathological diagnoses of 150 patients with comet tail artifacts who underwent laparoscopic cholecystectomy with pathologic confirmation. The extent of the involved lesion was classified as localized or diffuse, depending on the degree of involvement and the anatomical section of the gallbladder that was involved. This study evaluated the differences in clinical and imaging findings among pathologic diagnoses.

Results

All gallbladder lesions exhibiting the comet tail artifact on ultrasound examination were confirmed as benign gallbladder diseases after cholecystectomy, including 71 cases of adenomyomatosis (47.3%), 74 cases of chronic cholecystitis (49.3%), two cases of xanthogranulomatous cholecystitis (1.3%), and three cases of cholesterolosis (2.0%); there were two cases of coexistent chronic cholecystitis and low-grade dysplasia. There were no statistically significant differences in any of the clinical and ultrasonographic findings, with the exception of gallstones (P=0.007), among the four diseases. There were no significant differences in the average length, thickness, or number of comet tail artifacts among the four diagnoses. No malignancies were detected in any of the 150 thickened gallbladder lesions.

Conclusion

The ultrasonographic finding of the comet tail artifact in patients with thickened gallbladder lesions is associated with the presence of benign gallbladder diseases, and can be considered a reliable sign of benign gallbladder disease.

Indication and Usefulness of Bile Juice Cytology for Diagnosis of Gallbladder Cancer

Aim

We examined the effectiveness of bile juice cytology for distinguishing between benign and malignant gallbladder lesions of the protruding type with various sampling points, sampling methods, and macroscopic forms in order to discuss the effectiveness of the endoscopic transpapillary gallbladder drainage (ETGD) cytology.

Methods

We studied 162 cases of patients with a lesion localized within the gallbladder. At first, we examined the effectiveness for diagnosis of ETBD cytology using ERC and then that of the first ETGD cytology after placing the ETGD. Next, we examined the diagnostic effectiveness of the washed ETGD cytology by using the ETGD. Finally, we examined complications.

Results

In the final diagnoses, we identified 33 cases of adenocarcinoma, 10 cases of adenoma, 63 cases of ADM, 35 cases of nonneoplastic polyp, and 21 cases of chronic cholecystitis. It was found that the sensitivity of ETBD cytology was 3.6% and that of ETGD cytology was 59.1%. In the comparison of diagnostic effectiveness of cytologic diagnosis using samples of bile juice from the gallbladder collected by different methods, the sensitivities were 38.9% and 73.3% for the first and washed ETGD cytologies, respectively. In the comparison of the diagnostic effectiveness of gallbladder bile juice cytology using samples collected for different forms of lesion and by different methods, the sensitivities were 38.9% and 73.3%, respectively, for the first and washed ETGD cytologies for flat gallbladder wall thickening, while it was impossible to diagnose for lesions of GB polyp.

Conclusion

For diagnosis of gallbladder cancer, we consider that the ETGD cytology should be taken into consideration for lesions of flat gallbladder wall thickening, for which it is difficult to distinguish between benign and malignant lesions.

Diagnostic accuracy of MDCT in differentiating gallbladder cancer from acute and xanthogranulomatous cholecystitis

OBJECTIVE

To determine the diagnostic accuracy of multi-detector CT (MDCT) for differentiating gallbladder cancer from acute and xanthogranulomatous cholecystitis using previously described imaging features.

METHODS

In this IRB approved HIPAA-compliant retrospective cohort study, contrast-enhanced MDCT of histologically confirmed acute cholecystitis (n = 17), xanthogranulomatous cholecystitis (n = 25), and gallbladder cancer (n = 18) were reviewed independently by three abdominal radiologists blinded to outcome. The primary outcome was the diagnostic accuracy of MDCT for the differentiation of gallbladder cancer from cholecystitis (acute and xanthogranulomatous) using various imaging parameters. Kappa (κ) statistics and two-way mixed-model single-measure intra-class correlation statistics (ICC) were calculated for each imaging feature and the final radiologic diagnosis.

RESULTS

Inter-rater agreement was moderate to substantial (κ = 0.43-0.70), sensitivity 0.67-0.78, specificity 0.22-0.33 and the positive likelihood ratio was 4.28-8.56 for the differentiation of gallbladder cancer from benign gallbladder pathology. Only three imaging findings: disrupted gallbladder mucosa (κ = 0.68), intraluminal gallstones (κ = 0.66), and gallbladder wall thickness (ICC = 0.63) had substantial inter-rater agreement. The following had slight or no agreement: intramural hypoattenuating nodules (κ = 0.17), transient hepatic attenuation differences (κ = 0.14), gallbladder wall calcification (κ = -0.01), gallbladder wall enhancement (κ = 0.18), and omental or mesenteric invasion (κ = 0.08). In the final multivariate model, the following were significant predictors useful in making or excluding diagnosis of gallbladder cancer: focal gallbladder wall thickening (p = 0.003, OR: 13.09 [95% CI: 2.40-71.48]), pericholecystic "fat stranding" (p = 0.018, OR: 0.10 [95% CI: 0.01-0.66]), and maximum short axis lymph node diameter (p = 0.043, OR: 1.18 [95% CI: 1.00-1.38]).

CONCLUSION

MDCT has moderate sensitivity, poor specificity, and moderate-to-substantial inter-rater repeatability for the differentiation of gallbladder cancer from acute and xanthogranulomatous cholecystitis.

CT diagnosis of gallbladder adenomyomatosis: importance of enhancing mucosal epithelium, the "cotton ball sign"

OBJECTIVES

To determine the diagnostic value of the cotton ball sign and other CT features in patients with gallbladder (GB) wall thickenings (WTs).

METHODS

Three blinded readers reviewed the preoperative CT and MR images of 101 patients with pathologically confirmed GB adenomyomatosis (GA) (n = 34) and other benign (n = 29), malignant (n = 41), and premalignant (n = 2) GBWTs. Three readers analysed the morphological features of GBWT and presence of the "cotton ball sign", defined as fuzzy grey dots in GBWT or a dotted outer border of the inner enhancing layer on contrast-enhanced (CE) CT. In addition, the "pearl necklace sign" on MR was analysed.

RESULTS

In the GA group (n = 34), prevalence of the cotton ball sign and pearl necklace sign was 74% (25/34) and 44% (15/34), respectively. Presence of the cotton ball sign, smooth contour of the mucosa, double-layering enhancement, and enhancement degree weaker than the renal cortex on CT images were significant predictors of benign GBWT (p < 0.01). When differentiating GA from GB malignancy or premalignancy, accuracy of the cotton ball sign and pearl necklace sign was 81% (62/77) and 74% (57/77), respectively.

CONCLUSION

The cotton ball sign on CE-CT showed higher sensitivity and comparable specificity to those of the pearl necklace sign in differentiating GA from malignancy.

KEY POINTS

• Prevalence of the cotton ball sign on CT was 74% in gallbladder adenomyomatosis. • The cotton ball sign was useful in differentiating gallbladder adenomyomatosis from gallbladder cancer. • The cotton ball sign was more sensitive than the pearl necklace sign for adenomyomatosis diagnosis.

Diagnostic nomogram for gallbladder wall thickening mimicking malignancy: using contrast-enhanced ultrasonography or multi-detector computed tomography?

OBJECTIVES

To establish a diagnostic nomogram using contrast-enhanced ultrasonography (CEUS) in gallbladder wall thickening mimicking malignancy and compare with multi-detector computed tomography (MDCT).

METHODS

Seventy-two patients with gallbladder wall thickening on B-mode ultrasonography (BUS) were examined by CEUS to develop independent predictors for diagnosing gallbladder carcinoma. Among the 72 cases, 48 patients underwent both CEUS and MDCT. The diagnostic performances of different sets of CEUS criteria and MDCT were compared. A prediction model of malignancy using CEUS was developed. The performance of the nomogram was assessed with respect to its calibration, discrimination, and clinical usefulness.

RESULTS

Multivariate logistic regression indicated that inhomogeneous enhancement in the arterial phase was the strongest independent predictor of malignancy (odds ratio, OR 51.162), followed by interrupted inner layer (OR 19.788), washout time ≤40 s (OR 16.686), and wall thickness >1.6 cm (OR 3.019), which were all selected into the nomogram. Combined with the above significant features, the diagnostic performance of CEUS (AUC = 0.917) was higher than that of MDCT (AUC = 0.788, P = 0.070). The predictive model using CEUS showed good discrimination, with a concordance index of 0.974 (0.950 through internal validation), and good calibration. Decision curve analysis demonstrated that the nomogram was clinically useful.

CONCLUSIONS

CEUS could accurately differentiate between malignant and benign gallbladder wall thickening with equivalent efficacy compared to MDCT. The proposed nomogram could be conveniently used to facilitate the preoperative individualized prediction of malignancy in patients with gallbladder wall thickening.

Differentiation between gallbladder cancer with acute cholecystitis: Considerations for surgeons during emergency cholecystectomy, a cohort study

PURPOSE

Gallbladder cancer (GBCA) is an uncommon malignancy with vague and non-specific symptoms. GBCA is sometimes diagnosed after emergency cholecystectomy for acute cholecystitis. We investigated the differential diagnosis between GBCA with acute cholecystitis.

MATERIALS AND METHODS

Thirteen patients were diagnosed with GBCA after emergency cholecystectomy carried out for acute cholecystitis. A radiologist who was blinded to the final diagnoses retrospectively reviewed the computed tomography (CT) scans of the patients with GBCA and 25 patients with acute cholecystitis. We retrospectively reviewed the medical records of these patients and compared the clinical characteristics and CT findings between patients with GBCA and those with acute cholecystitis. We also investigated the prognostic factors in patients with GBCA who underwent emergency cholecystectomy.

RESULTS

Gallbladder (GB) stones were found more often in patients with acute cholecystitis (n = 17, 68%) than in patients with GBCA (n = 7, 53.8%) (p = 0.486). Patients with GBCA showed typical GB masses or focal enhanced wall thickening when compared to diffuse wall thickening in patients with acute cholecystitis. Some GBCA patients showed irregular mural thickening and GB enhancement. Differentiating carcinoma from acute cholecystitis might sometimes not possible, but the latter group of patients had significantly lower C-reactive protein (CRP) levels (p = 0.033) and less regional fat stranding (p = 0.047). Survival was significantly affected by aggressive tumor characteristics (lymphatic invasion [p = 0.025], depth of tumor invasion [p = 0.004]) or R0 resection (p = 0.013) rather than bile spillage (p = 0.112).

CONCLUSIONS

Surgeons deciding on emergency cholecystectomy for elderly patients with acute cholecystitis must suspect GBCA in patients with a low CRP level, irregular mural thickening or enhancement of GB without regional fat stranding.

Imaging Evaluation of Enhancement Patterns of Flat Gall Bladder Wall Thickening and Its Correlation with Clinical and Histopathological Findings

INTRODUCTION

Gall bladder Wall Thickening (GWT) is caused by wide spectrum of diseases. Initially Ultrasound (USG) was used as imaging modality for screening of acute abdomen because of its high sensitivity and real time character. Now, Computed Tomography (CT) is used because of its high temporal and spatial resolution.

AIM

Evaluation of GWT and its enhancement patterns on contrast enhanced CT scan in a bid to differentiate benign from malignant causes and to correlate the imaging features with clinical and histopathological findings.

MATERIALS AND METHODS

It was a hospital based prospective study in which USG was done as an initial modality for screening and Multi Detector Computed Tomography (MDCT) scan was done later on for detailed evaluation of enhancement patterns of GWT. The study cases were then divided into five CT patterns according to enhancement patterns. The diagnostic performance of MDCT was compared with histopathological and serological findings. Relevant history, clinical examination and routine investigations were done.

RESULTS

The one layered pattern with a heterogeneously enhancing thick layered pattern (Type 1) was significantly associated with gall bladder cancer (p<0.001). The sensitivity and specificity of Type 1 enhancement pattern on CT for predicting the Gall Bladder (GB) malignancy were 90.476% and 97.43% respectively. The positive and negative predictive values were 95% and 95%, respectively. Focal wall thickening, irregular margin character and hepatic infiltration by GWT and lymphadenopathy were other findings that predict malignancy (p-value<0.05).

CONCLUSION

MDCT enhancement patterns of a thickened GB wall and associated findings were helpful in differentiating malignant GWT from benign GWT.

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.

Gallbladder Tuberculosis Mimicking Gallbladder Carcinoma: A Case Report and Literature Review

Gallbladder tuberculosis (GT) is extremely rare, and it is difficult to differentiate from other gallbladder diseases, such as gallbladder carcinoma and Xanthogranulomatous Cholecystitis. A correct preoperative diagnosis of GT is difficult. The final diagnosis is usually made postoperatively according to surgical biopsy. Here, we report a case of a patient who underwent surgery with the preoperative diagnosis of gallbladder carcinoma. We reviewed the literature and present the process of differential diagnosis between two or more conditions that share similar signs or symptoms.

A literature review of radiological findings to guide the diagnosis of gallbladder adenomyomatosis

BACKGROUND

Gallbladder adenomyomatosis (GA) is a benign gallbladder entity discovered as an asymptomatic gallbladder mass. Since gallbladder cancer is in the differential diagnosis for gallbladder masses, the ability to differentiate benign disease avoids a more extensive oncologic resection. This study sought to review imaging modalities used to diagnose GA.

METHODS

PubMed and SciVerse Scopus were systematically searched using the terms: "gallbladder adenomyomatosis" and "gallbladder imaging" for articles published between January 2000 and January 2015.

RESULTS

A total of 14 articles were reviewed in this analysis. Contemporary series report the use of ultrasound (US), computed tomography (CT) or magnetic resonance imaging (MRI) in GA imaging. Ultrasound detection of Rokitansky-Aschoff sinuses, visualized as small cystic spaces with associated "comet-tail" or "twinkling" artifact, is pathognomonic for GA. A "Pearl-Necklace" sign of small connected sinuses on MRI or "Rosary" sign on CT are additional characteristics that may assist in establishing a diagnosis.

CONCLUSION

Ultrasound is the most commonly used tool to investigate GA. If not diagnostic, CT or MRI are effective in attempting to differentiate a benign or malignant cholecystic mass. Characteristic signs should lead the surgeon to perform a laparoscopic cholecystectomy in symptomatic patients or manage non-operatively in asymptomatic patients.

Polypoid lesions of the gallbladder: disease spectrum with pathologic correlation

Gallbladder polyps are seen on as many as 7% of gallbladder ultrasonographic images. The differential diagnosis for a polypoid gallbladder mass is wide and includes pseudotumors, as well as benign and malignant tumors. Tumefactive sludge may be mistaken for a gallbladder polyp. Pseudotumors include cholesterol polyps, adenomyomatosis, and inflammatory polyps, and they occur in that order of frequency. The most common benign and malignant tumors are adenomas and primary adenocarcinoma, respectively. Polyp size, shape, and other ancillary imaging findings, such as a wide base, wall thickening, and coexistent gallstones, are pertinent items to report when gallbladder polyps are discovered. These findings, as well as patient age and risk factors for gallbladder cancer, guide clinical decision making. Symptomatic polyps without other cause for symptoms, an age over 50 years, and the presence of gallstones are generally considered indications for cholecystectomy. Incidentally noted pedunculated polyps smaller than 5 mm generally do not require follow-up. Polyps that are 6-10 mm require follow-up, although neither the frequency nor the length of follow-up has been established. Polyps that are larger than 10 mm are typically excised, although lower size thresholds for cholecystectomy may be considered for patients with increased risk for gallbladder carcinoma, such as patients with primary sclerosing cholangitis.

Gallbladder carcinoma: causes of misdiagnosis at CT

Gallbladder carcinomas can present with varied imaging features on computed tomography. The three major imaging features include (1) focal or diffuse wall thickening with or without irregularity of the gallbladder; (2) polypoidal intraluminal mass; and (3) large mass obscuring and replacing the gallbladder, often extending to the liver. Patterns of wall thickening or polypoid growth are often confused with various benign gallbladder diseases due to overlap of imaging findings. Moreover, gallbladder carcinomas that coexist with benign gallbladder diseases make accurate preoperative diagnosis more difficult. Recently, high-resolution ultrasound (HRUS) has been regarded as a problem-solving tool for gallbladder diseases. In this article, we will illustrate various imaging presentations of gallbladder cancer, along with imaging pitfalls and recently updated HRUS findings.

Clinical characteristics of incidental or unsuspected gallbladder cancers diagnosed during or after cholecystectomy: A systematic review and meta-analysis

AIM: To perform a systematic review of incidental or unsuspected gallbladder (GB) cancer diagnosed during or after cholecystectomy.

METHODS: Data in PubMed, EMBASE, and Cochrane Library were reviewed and 26 publications were included in the meta-analysis. The inclusion criterion for incidental GB cancer was GB cancer diagnosed during or after cholecystectomy that was not suspected at a preoperative stage. Pooled proportions of the incidence, distribution of T stage, and revisional surgery of incidental GB cancer were analyzed.

RESULTS: The final pooled population comprised 2145 patients with incidental GB cancers. Incidental GB cancers were found in 0.7% of cholecystectomies performed for benign gallbladder diseases on preoperative diagnosis (95%CI: 0.004-0.012). Nearly 50% of the incidental GB cancers were stage T2 with a pooled proportion of 47.0% (95%CI: 0.421-0.519). T1 and T3 GB cancers were found at a similar frequency, with pooled proportions of 23.0% (95%CI: 0.178-0.291) and 25.1% (95%CI: 0.195-0.317), respectively. The pooled proportion that completed revisional surgery for curative intent was 40.9% (95%CI: 0.329-0.494). The proportion of patients with unresectable disease upon revisional surgery was 23.0% (95%CI: 0.177-0.294).

CONCLUSION: A large proportion of incidental GB cancers were T2 and T3 lesions. Revisional surgery for radical cholecystectomy is warranted in T2 and more advanced cancers.

A porcelain gallbladder and a rapid tumor dissemination

Introduction

Porcelain gallbladder is a very rare entity that consists of a calcification of the gallbladder wall, and is associated with carcinoma in 12.5–62% of patients, although recent studies suggest weaker association.

Case report

We describe an 80-year-old woman who presented with colicky abdominal pain in the right upper quadrant, radiating to the back and associated with vomiting. Physical examination revealed jaundice, murphy's sign was negative.

Hepatic-biliary tract ultrasound revealed porcelain gallbladder, she was referred to the surgical team for a scheduled cholecystectomy. A month later, she presented diffuse abdominal pain. Imaging studies showed a disseminated process affecting liver's segments, capsule, and hilum; and lungs. An aggressive surgical treatment was dismissed, and was referred to the oncology department.

Discussion

There is controversy in the harboring risk of malignancy of the porcelain gallbladder. While it seems that the current data points towards a lower risk of degeneration, it is also demonstrated that patients with gallbladder wall calcifications are indeed statistically at risk of gallbladder cancer. Laparoscopic cholecystectomy has become a safe and efficient approach recommended for patients with gallbladder symptoms directly related or unrelated to gallbladder wall calcifications. In this case, a pathological gallbladder, very quickly evolved into an inoperable tumor with a poor prognosis.

Conclusion

This report heightens that with US evidence of porcelain gallbladder, an urgent CT scan should be carried out to assess an underlying malignancy, and a simple cholecystectomy should be done urgently rather than on a routine elective list to prevent possible malignant change if possible.

•

We report a patient with advanced gallbladder porcelain.

•

Porcelain gallbladder is a very rare entity found in <1% of cholecystectomies.

•

It consists of calcification of the gallbladder wall.

•

The rapid progression of cancer in a porcelain gallbladder is more unusual.

Contrast-enhanced harmonic endoscopic ultrasonography in the differential diagnosis of gallbladder wall thickening

BACKGROUND AND AIMS

Differentiation of gallbladder (GB) carcinoma from benign GB wall thickening is challenging. The recent introduction of second-generation ultrasonic contrast agents has made contrast harmonic imaging with EUS possible. The aim of our study was to evaluate the utility of contrast-enhanced harmonic EUS (CH-EUS) for the differential diagnosis of GB wall thickening.

METHODS

Thirty-six consecutive patients with GB wall thickening imaged by CH-EUS and then underwent surgery were enrolled in this study. After the lesions were observed with conventional harmonic EUS (H-EUS), CH-EUS was performed with intravenous injection of 0.015 ml/kg of Sonazoid. Three reviewers with various levels of experience of EUS (Reviewer A: experienced endosonographer, B: EUS trainee, C: experienced gastroenterologist with expertise in transabdominal ultrasound but no EUS experience) were blinded to findings of recorded video of H-EUS and CH-EUS. The diagnostic accuracy of H-EUS and CH-EUS for malignant GB wall thickening was compared.

RESULTS

Final diagnoses based on surgical histology were GB carcinoma in 16, cholecystitis in 11, adenomyomatosis in 6 and cholesterolosis in 3. Overall sensitivity, specificity and accuracy for diagnosing malignant GB wall thickening of H-EUS and CH-EUS were 83.3 versus 89.6, 65 versus 98% (p < 0.001) and 73.1 versus 94.4% (p < 0.001). The inter-observer agreement for H-EUS was moderate (κ = 0.51), whereas that for CH-EUS was substantial (κ = 0.77). The inhomogeneous enhanced pattern on CH-EUS was a strong predictive factor of malignant GB wall thickening.

CONCLUSION

CH-EUS has the potential to improve the preoperative diagnostic accuracy and inter-observer agreement in the differential diagnosis of GB wall thickening.

Gallbladder cancer in Chile: Pathologic characteristics of survival and prognostic factors: analysis of 1,366 cases

OBJECTIVES

To explore gallbladder cancer (GBC), the second leading cause of cancer-related death in women in Chile.

METHODS

Analysis of macroscopic and microscopic variables, morphometry, and survival in 1,366 patients with GBC.

RESULTS

Patients comprised 1,138 women and 228 men; diagnoses included 213 (15.6%) cases of mucosal carcinoma, 132 (9.7%) cases of muscular carcinoma, 316 (23.1%) cases of subserosal carcinoma, 382 (28.0%) cases of serosal carcinoma, and 323 (23.6%) cases beyond the serosa. Women older than 55 years with a gallbladder length greater than 9.5 cm had a five-times-greater relative risk of cancer. Those with a gallbladder wall thickness less than 7 mm had a better 5-year survival rate than those with a gallbladder wall thickness greater than 10 mm (P = .0001). Patients who had cholesterolosis of the gallbladder had 9.2 times less probability of having cancer. The infiltration level of the gallbladder wall was the most important independent prognostic factor (P < .001), followed by differentiation and lymphatic involvement (P < .001 and P = .05, respectively). Vascular infiltration had a mortality rate of 100%.

CONCLUSIONS

Morphologic features are strongly associated with the prognosis of GBC and must be taken into consideration when supplementary treatment is recommended.