From the archives of the AFIP. Benign tumors and tumorlike lesions of the gallbladder and extrahepatic bile ducts: radiologic-pathologic correlation. Armed Forces Institute of Pathology

Magnetic resonance imaging features of bile duct adenoma

Objectives

To evaluate the magnetic resonance imaging (MRI) features of bile duct adenoma.

Methods

The data of 28 patients [with 32 pathologically confirmed bile duct adenomas, including 15 with malignant change (malignant group) and 17 without malignant change (benign adenoma group)] were retrospectively reviewed. Abdominal MRI was performed for all patients; in addition, dynamic enhanced MRI was performed for 18 lesions. The MRI features, including lesion location, maximum size, morphology, signal characteristics, enhancement type, and appearance of the bile duct, were assessed by two abdominal radiologists. Apparent diffusion coefficient (ADC) values were measured and compared.

Results

Of the 32 bile duct adenomas, 22 (68.75%) involved the common bile duct (CBD). While 14/32 (43.75%) lesions presented as focal eccentric-type masses, 9/32 (28.13%) presented as plaque-like masses, 4/32 (12.50%) as bile duct casting masses, and 5/32 (15.62%) as infiltrative masses. A frond-like superficial appearance was seen in 8/32 (25%) lesions. Infiltrative masses were significantly more common in the malignant group than in the benign adenoma group (P = 0.015). While 23/32 (71.88%) lesions were isointense on T1-weighted imaging (T1WI), 24/32 (75%) were hyperintense on T2-weighted imaging (T2WI). Bile duct dilatation was present upstream of the lesion in all cases. Bile duct dilatation at the lesion was seen in 24/32 (75%) cases and downstream of the lesion in 6/32 (18.75%) cases. Of the 18 lesions that underwent dynamic enhanced MRI, 14 (77.78%) showed moderate enhancement and 13 (72.22%) showed persistent enhancement. On diffusion-weighted imaging (DWI), 27/32 (84.37%) lesions showed hyperintensity. Mean ADC value was comparable between the malignant group and the benign adenoma group (P = 0.156).

Conclusions

Bile duct adenoma primarily presents as intraductal growth in the CBD, usually with bile duct dilatation at the lesion site or upstream to it. Most lesions are isointense on T1WI, are hyperintense on T2WI and DWI, and show moderate enhancement. A superficial frond-like appearance of the lesion and bile duct dilatation at the lesion or downstream to it might be characteristics of bile duct adenoma. An infiltrative appearance might indicate malignant transformation.

Imaging mimickers of cholangiocarcinoma: a pictorial review

Cholangiocarcinoma (CCA) is the second most common primary hepatobiliary malignancy and presents as three separate morphological subtypes; namely mass-forming, periductal-infiltrating, and intraductal-growing patterns. Each of these subtypes have distinct imaging characteristics, as well as a variety of benign and malignant mimics, making accurate diagnosis of CCA on imaging challenging. Whilst histopathological examination is required to arrive at a definitive diagnosis, it is still important for radiologists to be cognizant of these entities and provide reasonable differential diagnoses, as these potentially have a large impact on patient management. This pictorial essay illustrates the three morphological subtypes of CCA, as well as some important mimics for each subtype, that are encountered in clinical practice.

Morphological and immunophenotypical analysis of the spindle cell component in adenomyomatous hyperplasia of the gallbladder

Background

Adenomyomatous hyperplasia (AMH) of the gallbladder, reported in 1-8.7% of cholecystectomies, consists of cystically dilated sinuses/glands with a surrounding spindle cell proliferation which is thought to be composed of smooth muscle cells. Myofibroblasts are contractile cells that secrete a variety of biochemical modulators causing a “field-effect”. Myofibroblasts can be immunohistochemically distinguished from smooth muscle cells by their desmin negativity.

Methods

Eighteen cases of AMH and five cases each of chronic follicular cholecystitis, chronic cholecystitis, gallbladder carcinoma and 10 colonic diverticular disease were stained with actin and desmin. The percentage of myofibroblasts was estimated by the difference between actin and desmin staining in the same field. Statistical anlysis was performed using SPSS 22.0.

Results

The percentage of actin staining was significantly higher in AMH and gallbladder carcinoma compared to chronic follicular and chronic cholecystitis (p = 0.04). The percentage of desmin staining did not show any significant difference between the four groups. The estimated myofibroblastic population was significantly higher in AMH when compared to chronic follicular and chronic cholecystitis (p = 0.005).

Conclusion

The spindle cell proliferation around cystically dilated glands in AMH is composed predominantly of myofibroblasts and of smooth muscle cells as previously described. This finding suggest a derangement in epithelial-stromal interactions as the underlying pathophysiology in AMH.

Xanthogranulomatous cholecystitis mimicking advanced gallbladder carcinoma - Analysis of 8 cases

Background/Aim

Xanthogranulomatous cholecystitis (XGC) is a rare destructive inflammatory disease of the gallbladder. It is frequently misdiagnosed as gallbladder carcinoma (GBC) as it mimics latter with regard to clinical manifestations, imaging and intraoperative findings, often leading to extended surgical resection in these patients. The aim of this study was to evaluate the diagnostic dilemma of XGC cases clinico-radiologically diagnosed with GBC.

Materials and Methods

From January 2017 to June 2019, a total of eight cases histopathologically diagnosed as XGC, were misdiagnosed with GBC based on preoperative and intra-operative findings. The clinical characteristics, imaging, intra-operative findings, and surgical data of these patients were collected and analyzed.

Results

A total of 2154 cholecystectomy specimens were received in the histopathology section during the study period. Sixty-nine cases (3.2%) were histologically diagnosed as XGC, of which 8 cases (11.6%) were preoperatively diagnosed with GBC. These cases were predominantly seen in males in the age range of 24-62 years. The most common clinical presentation was chronic cholecystitis. Gallstones were present in all the 8 cases. Six cases presented with heterogeneous enhancement within thickened gallbladder walls on imaging. Intraoperatively, adhesions to adjacent organs were observed in seven cases. All these eight cases misdiagnosed with GBC underwent aggressive surgical treatment following which histopathology ultimately revealed XGC.

Conclusion

Neither clinical manifestations nor laboratory tests/radiological methods can provide an effective means of differentiating between XGC and GBC. Preoperative diagnosis is difficult, and histopathology remains the gold standard to differentiate the two entities.

Pyloric adenomatous carcinoma of the gallbladder following laparoscopic cholecystectomy: A case report

INTRODUCTION

Adenoma and intra-adenoma carcinoma of the gallbladder are relatively rare diseases, and the World Health Organization classification reports a frequency of 0.3% for gallbladder adenomas. Precise preoperative diagnosis of gallbladder cancer, especially in the early stages, is challenging. Herein, we report a case of pyloric adenomatous carcinoma of the gallbladder, diagnosed by laparoscopic cholecystectomy and pathology, along with a literature review. This case was reported in accordance with the SCARE 2020 Guideline (Ref).

PRESENTATION OF CASE

A 62-year-old woman was diagnosed with a 4-mm polypoid lesion in the gallbladder during a medical examination. The patient was followed-up by ultrasonography (US) once a year and was referred to our department because of an increase in size. Carcinoembryonic antigen and carbohydrate antigen 19-9 levels were within normal limits. Abdominal ultrasonography revealed a pedunculated polypoid lesion in the body of the gallbladder measuring 8 mm. Computed tomography demonstrated that the whole tumor was enhanced in the early phase without significant lymph node enlargement. Magnetic resonance cholangiopancreatography demonstrated a type Ip polypoid lesion located in the body of the gallbladder without pancreaticobiliary junctional abnormalities. Endoscopic ultrasound detected a superficial nodular-type Ip polypoid lesion in the gallbladder body with a parenchyma-like internal echogenic pattern.

DISCUSSION

Based on these findings, the patient was diagnosed with gallbladder adenoma, and laparoscopic cholecystectomy was performed. Histopathological examination revealed the tumor was a papillary growth of atypical high columnar epithelial cells. The final diagnosis was pyloric adenoma with high-grade dysplasia and intra-adenoma carcinoma. The patient is currently undergoing outpatient follow-up without recurrence for 1 year.

CONCLUSION

Early gallbladder carcinoma with adenoma should be considered in patients with small gallbladder polypoid lesions. Considering the surgical stress of cholecystectomy and the malignant potential of gallbladder cancer, preceding surgery would be acceptable.

Gallbladder adenomyomatosis: Diagnosis and management

INTRODUCTION

Gallbladder adenomyomatosis is a benign acquired gallbladder disease. It can mimic cancer on radiological findings, leading to a diagnostic dilemma. The management and prognosis of these two gallbladder anomalies are entirely different. Therefore, it is essential to recognize the pathognomonic features of gallbladder adenomyomatosis is in order to accurately diagnose this pathology. This paper presents two encountered cases of gallbladder adenomyomatosis is, their diagnostic modalities as well as the algorithmic approach of their management. These two-case reports have been reported in line with the SCARE Criteria 2020 [1].

PRESENTATION OF CASE

Patient-1 was symptomatic. He was explored by an abdominal ultrasound picturing gallbladder wall thickening while the biopsy showed pleomorphic proliferation of inflammatory cells. An examination of the liver with MRI was indicated, showing diffuse parietal thickening with multiple cystic pockets. He underwent laparoscopic cholecystectomy with simple operative follow-up. Patient 2 was asymptomatic, a staging CT scan of acute pancreatitis revealed focal mural thinking of the gallbladder wall. A liver MRI showed an intramural cystic formation in the vesicular fundus. Given the inconclusive imaging results, laparoscopic cholecystectomy was performed. Histological examination confirmed the diagnosis of GA.

DISCUSSION

Adenomyomatosis is usually asymptomatic. Imaging can confirm the diagnosis of gallbladder adenomyomatosis without the need for invasive procedures such as vesicular biopsy. Histologic examination can also confirm the diagnosis when cholecystectomy is done. High resolution ultra-sound is the most efficient radiological examination. Laparoscopic cholecystectomy is the gold standard for symptomatic GA or radiological suspicion of a gallbladder cancer.

CONCLUSION

The practitioner should always consider gallbladder carcinoma before confirming the GA, as they share the same features but with a far worse prognosis. The likelihood of malignancy depends on radiological characteristics. In the case of inconclusive findings, cholecystectomy is justified.

Complications of cholecystitis: a comprehensive contemporary imaging review

Acute cholecystitis is a common cause of right upper quadrant pain in patients presenting to the emergency department. Ultrasound, computed tomography, HIDA scans, and magnetic resonance imaging are increasingly utilized to evaluate suspected cases. The prognosis of acute cholecystitis is usually excellent with timely diagnosis and management. However, complications associated with cholecystitis pose a considerable challenge to the clinician and radiologist. Complications of acute cholecystitis may result from secondary bacterial infection or mural ischemia secondary to increased intramural pressure. The recognized subtypes of complicated cholecystitis are hemorrhagic, gangrenous, and emphysematous cholecystitis, as well as gallbladder perforation. Acute acalculous cholecystitis is a form of cholecystitis that occurs as a complication of severe illness in the absence of gallstones or without gallstone-related inflammation. Complicated cholecystitis may cause significant morbidity and mortality, and early diagnosis and recognition play a pivotal role in the management and early surgical planning. As appropriate utilization of imaging resources plays an essential role in diagnosis and management, the emergency radiologist should be aware of the spectrum of complications related to cholecystitis and the characteristic imaging features. This article aims to offer a comprehensive contemporary review of clinical and cross-sectional imaging findings of complications associated with cholecystitis. In conclusion, cross-sectional imaging is pivotal in identifying the complications related to cholecystitis. Preoperative detection of this complicated cholecystitis can help the care providers and operating surgeon to be prepared for a potentially more complicated procedure and course of recovery.

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.

Selective or Routine Histology of Cholecystectomy Specimens for Diagnosing Incidental Carcinoma of Gallbladder and Correlation with Careful Intraoperative Macroscopic Examination? A Systematic Review

BACKGROUND

Selective or Routine histology of cholecystectomy specimens for benign gallbladder disease has always been a matter of debate because of the low prevalence and bad prognosis associated with gall bladder carcinoma. The objective of this study is to ascertain whether selective histology can be preferred over Routine histology without any harm.

METHODS

This systematic review is conducted according to PRISMA's checklist; relevant articles were searched in the database until September 1 2020 in PubMed, Scopus, Science Direct, and Web of Science databases, manually, with search queries and without date restrictions. Studies included in this systematic review involved patients who underwent cholecystectomy for benign gallbladder disease and were diagnosed with gallbladder carcinoma incidentally either after selective or routine histology of the gallbladder.

RESULTS

A total of 24 routine or selective histology recommending studies were selected for the systematic review after following the inclusion and exclusion criteria. These studies comprised 77,213 numbers of patients and 486 numbers of Malignancies. These studies correlate the number of IGBC diagnosed histologically with the number of IGBC's that were suspected by the surgeons intraoperative by macroscopy. Routine recommending studies show a significant number of IGBC diagnosed histologically as missed by surgeons whereas the selective recommending studies show most of the histologically diagnosed IGBC already suspected by the surgeons intraoperative. When comparing the macroscopic details of the IGBC's between routine and selective studies, we found that there was significant overlap. Most of the findings missed by the surgeons as suspicious in routine studies were suspected by the surgeons involved in selective histology recommending studies. Thereby, favouring selective histology and emphasizing the need for careful intraoperative macroscopy for suspecting IGBC.

CONCLUSION

Selective Histological examination of cholecystectomy specimens can be preferred if a careful intraoperative macroscopic examination is done and patient risk factors are taken into consideration.

Gallbladder polyps ultrasound: what the sonographer needs to know

Gallbladder polyps are protuberances of the gallbladder wall projecting into the lumen. They are usually incidentally found during abdominal sonography or diagnosed on histopathology of a surgery specimen, with an estimated prevalence of up to 9.5% of patients. Gallbladder polyps are not mobile and do not demonstrate posterior acoustic shadowing; they may be sessile or pedunculated. Gallbladder polyps may be divided into pseudopolyps and true polyps. Pseudopolyps are benign and include cholesterolosis, cholesterinic polyps, inflammatory polyps, and localised adenomyomatosis. True gallbladder polyps can be benign or malignant. Benign polyps are most commonly adenomas, while malignant polyps are adenocarcinomas and metastases. There are also rare types of benign and malignant true gallbladder polyps, including mesenchymal tumours and lymphomas. Ultrasound is the first-choice imaging method for the diagnosis of gallbladder polyps, representing an indispensable tool for ensuring appropriate management. It enables limitation of secondary level investigations and avoidance of unnecessary cholecystectomies.

Successful preoperative diagnosis and minimally invasive surgery of bile duct schwannoma

Bile duct schwannomas are rare benign tumors that frequently mimic more life-threatening tumors. Till date, only a few of these tumors have been diagnosed preoperatively. Herein, we report the case of a 68-year-old man who presented with a 1-day history of epigastralgia. The patient was preoperatively diagnosed with bile duct schwannoma using transpapillary biliary forceps biopsy and underwent local resection without major complications. The findings of our study indicate that endoscopic tumor biopsy may be helpful in diagnosing bile duct schwannoma before surgery; thus, enabling surgeons to plan an appropriate surgery while avoiding overtreatment.

Ultrasonographic Measurements of the Liver, Gallbladder Wall Thickness, Inferior Vena Cava, Portal Vein and Pancreas in an Urban Region, Malaysia

Background:

Ultrasonographic (USG) measurements of the liver length, gallbladder wall thickness (GBWT), diameters of the inferior vena cava (IVC), portal vein (PV), and pancreas are valuable and reliable in diagnosis hepatobiliary and pancreas conditions. This study is aimed to determine the normal values of liver length, GBWT, AP diameters of the IVC and PV, AP diameter of the head and body of the pancreas.

Methods:

A prospective cross–sectional study was carried out in this study. A total of the 408 participants were randomly recruited using a systematic method. According to the USG reports, the subjects who had normal USG report for liver, biliary system, and pancreas were described as normals, whereas the subjects who had hepatobiliary diseases such as fatty liver, liver cysts, hemangioma, cirrhosis, gallbladder wall thickening, acute cholecystitis, gallstones, and polyps were recorded as abnormal subjects.

Results:

Of the 408 participants with a mean of 52.6 ± 8.4 years old. Of those, 294 (72.1%) participants were normal and 114 (27.9%) subjects were reported as abnormal. More than half of the study population was males, 52.9% versus 47.1% of females. There was a significant difference of liver length, head, and body of the pancreas between genders (P = 0.004, 0.002, and P < 0.001, respectively). Moreover, the pancreatic body only was significantly correlated with age (P = 0.026). There also was a significant difference of the liver length, head, and body of the pancreas between normal and abnormal subjects (P < 0.001, P = 0.007, and P < 0.001).

Conclusion:

Liver length, diameter of the head, and body of the pancreas were significantly associated with gender and hepatobiliary diseases. In addition, only the diameter of the body of the pancreas was significantly correlated with age.

Diffuse Neuromatosis of Intrahepatic and Extrahepatic Bile Ducts as a Rare Cause of Jaundice

Background

Neuroma of the biliary tree is extremely rare with no more than 100 cases reported so far. They mostly present with obstructive jaundice and have been commonly described after surgery or abdominal trauma. Although involvement of the extrahepatic bile duct is far more common, occurrence in the intrahepatic ducts has not so far been reported.

Case Report

We describe 3 cases of diffuse biliary tree neuroma affecting 3 females aged 53-68 years. None had a history of neurofibromatosis type1. All presented with progressive obstructive jaundice with no evidence of gallstones. A history of previous surgery was noted in 2 patients. Initial impression on clinical and imaging examination was highly suspicious for bile duct carcinoma in 2 patients. Histology showed diffuse neuromatous proliferation replacing and thickening the bile duct walls. The third patient had concurrent neuroma and recurrent cholangiocarcinoma causing great clinical confusion as initial biopsy showed only benign neuroma, but CA 19-9 was steadily increasing, necessitating a second biopsy which then confirmed recurrent carcinoma.

Conclusion

This uncommon cause of long-distance bile duct stenosis and progressive jaundice should be included in the differential diagnosis of bile duct neoplasms, in particular when there is a previous surgical history in this abdominal region.

Xanthogranulomatous cholecystitis: a rare gallbladder pathology from a single-center perspective

Purpose

The aim of this study was to review patients with xanthogranulomatous cholecystitis (XGC).

Methods

A total of 79 patients diagnosed with XGC were included in the study. The criteria for XGC in the pathology specimens were the presence of histiocytes, cholesterol deposits, lipids, and focal or widespread wall enlargement.

Results

Patients were diagnosed with XGC, of which 52 (65.8%) were male and 27 (34.2%) were female, creating a male-to-female ratio of 2:1. The mean age was 65.8 ± 14.3 years (range, 36–97 years). The most common presenting symptom was abdominal pain (63.3%), and the least common presenting symptom was jaundice (8.9%). Of the total, 25 patients were found to have pathological conditions with the potential to obstruct the bile duct or to slow bile flow. A frozen section examination was performed on 20 patients due to suspicion of a tumor by intraoperative macroscopic examination. However, no malignancy was detected in the cases who underwent a frozen section examination. An increase in wall thickness of the gallbladder was observed in 81.6% (n = 31) of the patients on computed tomography scans and in 81.8% (n = 18) of the patients on magnetic resonance imaging scans in which possible tumor lesions were reported, but no tumor was detected.

Conclusion

It is difficult to diagnose XGC either preoperatively or intraoperatively, and further imaging methods are needed in the preoperative period other than ultrasonography. However, a definitive diagnosis depends exclusively on pathologic examination.

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.

Recommendations for the Management of Incidental Hepatobiliary Findings in Adults: Endorsement and Adaptation of the 2017 and 2013 ACR Incidental Findings Committee White Papers by the Canadian Association of Radiologists Incidental Findings Working Group

The Canadian Association of Radiologists Incidental Findings Working Group consists of both academic subspecialty and general radiologists and is tasked with adapting and expanding upon the American College of Radiology incidental findings white papers to more closely apply to Canadian practice patterns, particularly more comprehensively dealing with the role of ultrasound and pursuing more cost-effective approaches to the workup of incidental findings without compromising patient care. Presented here are the 2020 Canadian guidelines for the management of hepatobiliary incidental findings. Topics covered include initial assessment of hepatic steatosis and cirrhosis, the workup of incidental liver masses identified on ultrasound and computed tomography (with algorithms presented), incidental gallbladder findings (wall thickening, calcification, and polyps), and management of incidental biliary dilatation.

Incidental Carcinoma after Cholecystectomy for Benign Disease of the Gallbladder: A Meta-Analysis

This study aimed to determine the incidence and the prognosis of incidental carcinoma of the gallbladder (IGBC) after cholecystectomy through a meta-analysis. This meta-analysis included 51 studies and 436,636 patients with cholecystectomy. The incidence rate of IGBC after cholecystectomy was 0.6% (95% confidence interval (CI) 0.5%-0.8%). The incidence rate of recent studies was not significantly different from those of past studies. The mean age and female ratio of the IGBC subgroup were not significantly different from those of the overall patient group. The estimated rates of IGBC were 13.0%, 34.1%, 39.7%, 22.7%, and 12.5% in the pTis, pT1, pT2, pT3, and pT4 stages, respectively. Patients with IGBC had a favorable overall survival rate compared to patients with non-IGBC (hazard ratio (HR) 0.574, 95% CI 0.445-0.739). However, there was no significant difference of disease-free survival between the IGBC and non-IGBC subgroups (HR 0.931, 95% CI 0.618-1.402). IGBC was found in 0.6% of patients with cholecystectomy. The prognosis of patients with IGBC was favorable compared to those with non-IGBC. In the pathologic examination after cholecystectomy for benign diseases, a sufficient examination for histology should be guaranteed to detect IGBC.

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.

Endoscopic mucosal resection of a bile duct polyp: A case report

BACKGROUND

Bile duct polyps are difficult to diagnose and are usually excised by open abdominal surgery or snare polypectomy using choledochoscopy via the T-tube sinus tract. However, these two resection methods require the surgeon to open the abdomen and cut the bile duct to place the “T” tube. Moreover, simple snare polypectomy, without submucosal injection, can only remove pedunculated polyps and not flat polyps. Therefore, a new method is required for the excision of bile duct polyps, including flat polyps.

CASE SUMMARY

A 63-year-old woman was hospitalized following epigastric pain lasting a month. She had a 30-year history of cholelithiasis and had undergone cholecystectomy because of cholecystolithiasis, and had undergone cholangiolithotomy twice due to choledocholithiasis. Computed tomography (CT) and magnetic resonance imaging showed a communication between the bile duct and duodenal bulb. Inside the communication, CT showed a high-density shadow which was a hypointense lesion in T2 weighted image. The lesion showed no enhancement in T1 weighted image contrast enhanced. Gastroscopy revealed an incarcerated bile duct stone in the anterior wall of the duodenal bulb, which was removed with a basket under gastroscopy. Thereafter, a choledochoduodenal fistula was revealed. Finally, a flat polyp was detected in the lower part of the common bile duct and was removed by endoscopic mucosal resection (EMR) through the fistula. To our knowledge, this is the first reported case of the removal of a bile duct polyp using EMR.

CONCLUSION

EMR is a safe, effective, and low-cost method for the resection of all bile duct polyps.

[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.

Magnetic resonance imaging (MRI) of perianal granular cell tumor: A case report and literature review

Granular cell tumor (GCT) is a rare soft tissue neoplasm. At present, there is limited information available on the incidence, diagnosis, and treatment of GCTs. Therefore, we perform magnetic resonance imaging (MRI) of a perianal GCT case and review the literature of other reported cases to obtain a more comprehensive understanding of the disease. Here, we describe a rare case of perianal GCT in a 53-year-old female who presented with recurrent abdominal pain. Contrast-enhanced MRI demonstrated a well-defined perianal GCT mass, and the diagnosis was confirmed by immunostaining after mass excision. During a 10-month follow-up, there had been no evidence of recurrence. In addition, we discussed the findings of other perianal GCT cases, with regard to their age, gender, MRI analysis results, pathologic features, and treatment outcomes.

Biliary Mucinous Cystic Neoplasm: a Classic Presentation of a Rare Neoplasm

Biliary mucinous cystic neoplasms are rare parenchymal neoplasms with a considerable malignant potential. Due to a lack of diagnostic imaging criteria, histopathologic evaluation remains the definitive method of diagnosis. Resection is the treatment of choice. Here, the authors present a case of biliary mucinous neoplasm in a 39-year-old female with the associated radiographic and histopathologic findings.

Gallbladder polyps - a follow-up study after 11 years

Background

The aim of our study was to investigate the prevalence and natural long-term progression of gallbladder polyps in a random sample of the general population.

Methods

Four hundred and thirteen subjects (190 women, 223 men; aged 29–75 years) were studied first in 2002 and again eleven years later in 2013. All subjects were interviewed using a standardised questionnaire, anthropometric data were recorded, and an abdominal ultrasound scan was carried out.

Results

The prevalence of gallbladder polyps was 6.1% (115/1880) in the 2002 study and 12.1% (50/413) in the 2013 follow-up study. After eleven years, 36 subjects (8.7%, 36/413) had developed new polyps, thirteen subjects (48.1%, 13/27) no longer had gallbladder polyps, and 14 subjects (51.9%, 14/27) still had polyps. The number of polyps had increased in six of these subjects (43%, 6/14), decreased in a further six (43%, 6/14), and remained unchanged in two (14%, 2/14). The mean polyp size was 4.7 mm (± 2.2 mm, range 2–20 mm) in 2002 and 4.0 mm (± 1.9 mm, range 0.5–11 mm) at follow-up. A decrease in polyp size was noted in seven (50%) of the 14 subjects, an increase in size in five subjects (35.7%), and no change in two subjects (14.3%). The shape of the polyps had changed from pedunculated to sessile in two subjects (14.3%, 2/14) and from sessile to pedunculated in one subject (7.1%, 1/14).

Conclusions

In long-term follow-up, the prevalence of gallbladder polyps increased, with new lesions developing in 8.7% of the population. Polyps persisted in 51.9% of the subjects who had them in the original study and disappeared in the other 48.1%.

Uncommon Intraluminal Tumors of the Gallbladder and Biliary Tract: Spectrum of Imaging Appearances

Intraluminal pathologic conditions of the bile ducts and gallbladder are common, most frequently consisting of calculi and adenocarcinoma. In recent years, intraductal papillary neoplasm of the bile ducts (IPN-B), which is analogous to intraductal papillary mucinous neoplasm of the pancreas, has been recognized as a distinct pathologic entity and a precursor lesion to adenocarcinoma of the bile ducts. Intraductal tubulopapillary neoplasm (ITPN) of the bile duct was subsequently described as a distinct pathologic entity. With increased awareness and advances in imaging techniques, these lesions are diagnosed with increased frequency at preoperative imaging. A similar neoplasm in the gallbladder is referred to as intracholecystic papillary neoplasm. These lesions are often diagnosed at a preinvasive stage and have a better prognosis than invasive cholangiocarcinoma when treated with curative resection, underscoring the importance of an accurate imaging diagnosis. The most common causes of polypoid lesions of the gallbladder are cholesterol polyps and adenomyomatosis. These lesions need to be differentiated from the less common but clinically important adenocarcinoma of the gallbladder. Imaging is crucial to identify polyps that are at high risk for malignancy so that the appropriate management choice between imaging follow-up and cholecystectomy can be made by the treating physicians. Other less common gallbladder tumors, such as gallbladder adenomas, lymphoma, and metastases to the gallbladder, can manifest as intraluminal tumors; and awareness of these lesions is also important. In this article, the recent literature is reviewed; and the imaging appearances, histopathologic findings, and management of uncommon intraluminal tumors of the bile ducts and gallbladder and their mimics are discussed. ^©RSNA, 2019.

Imaging and clinical features of xanthogranulomatous pancreatitis: an analysis of 10 cases at a single institution

PURPOSE

The purpose of the study was to investigate the imaging and clinical features of xanthogranulomatous pancreatitis (XGP).

METHODS

This retrospective series study included 10 patients with pathology-proven XGP. Two radiologists reviewed the computed tomography (CT) and magnetic resonance imaging (MRI) in consensus to determine the morphological features of XGP. The lesion enhancement pattern on dynamic contrast-enhanced scans and the MR signal intensity were also evaluated. Clinical data including symptoms, underlying pancreatic disease, and laboratory findings were reviewed.

RESULTS

Two XGP cases were of a solid type; six were of cystic type, and two were mixed type. XGP usually showed a lobulated contour (90%) and heterogeneous enhancement (100%), with lesion size varying from 2 to 11 cm. Perilesional infiltration was common (90%), but pancreatic duct dilatation was less frequent (30%). Cystic type XGP mostly had an irregular thick wall (83%). On dynamic contrast-enhanced CT/MRI, XGP enhanced progressively from arterial to portal or delayed phases. Lesions appeared hypointense on T1-weighted images (89%) and hyperintense on T2-weighted images (100%). All lesions appeared hyperintense on diffusion-weighted images, with the majority (78%) showing diffusion restriction on apparent diffusion coefficient maps. The patients often had abdominal pain (80%) and underlying pancreatic disease (80%), but mostly had normal or clinically insignificant laboratory findings.

CONCLUSIONS

XGP typically manifests as a clinically silent lobulated heterogeneous mass, with a progressive enhancement pattern and/or irregular thick wall, and diffusion restriction on CT/MRI. Awareness of the imaging and clinical features of XGP may help differentiate it from pancreatic neoplasms, thereby reducing unnecessary surgery.

Factors Associated with Premalignant Epithelial Changes in Chronic Calculous Cholecystitis: A Case-Control Study

INTRODUCTION

Gallstones are known to be associated with premalignant changes in the gallbladder epithelium that range from atypical hyperplasia, metaplasia, dysplasia to carcinoma. Recognition of factors associated with these changes in patients with gallstones can potentially be helpful in identifying patients to whom prophylactic cholecystectomy can be offered to reduce the chances of developing carcinoma.

OBJECTIVE

To identify factors associated with premalignant epithelial changes including atypical hyperplasia, metaplasia, and dysplasia in gallbladder mucosa in patients with chronic calculus cholecystitis.

MATERIALS AND METHODS

This was retrospective case-control study conducted over a period of 10 years from 2004 to 2014. Cases were patients with reported histopathological premalignant epithelial changes along with chronic calculus cholecystitis, and controls were patients without premalignant epithelial changes but chronic calculus cholecystitis. Controls were twice the number of the cases.

RESULTS

Over study period, 92 patients were reported to have premalignant epithelial changes on gall bladder histopathology for whom 184 controls were selected. Of cases, 61 (66%) patients had atypical hyperplasia, while metaplasia and dysplasia were present in 26 (28%) and 5 (5%) cases, respectively. Mean age was 47.5 ± 14.5 years, and 74% of the study population were female. Wall thickness of more than 3 mm (OR = 4.14, p value < 0.001) turned out to be statistically significant independent variables associated with premalignant lesions in gallbladder mucosa.

CONCLUSION

Odds of premalignant epithelial change in gall bladder mucosa in patients with gall bladder wall thickness of more than 3 mm is four times the odds of patients with wall thickness less than 3 mm, and the effect is statistically significant. Prophylactic cholecystectomy should be considered for this group of patients.

Adenomyomatous hyperplasia of distal common bile duct: a case report and review of the literature

Adenomyomatous hyperplasia (AH) is commonly found in the gallbladder and is considered a tumor-like inflammatory lesion arising from Rokitansky-Aschoff sinus. It is extremely rare in the extrahepatic bile duct and only 15 cases have been reported to date. We describe a 63-year-old male patient who presented with cholangitis, underwent an extensive diagnostic workup, and ultimately had a Whipple procedure. Final pathology showed a 2.0 × 1.5 × 0.5 cm³ granular lesion in the distal common bile duct. There was prominent biliary epithelial proliferation with tubular–papillary architecture and minimal nuclear atypia in association with chronic inflammation, stroma reaction and smooth muscle proliferation. AH of the extrahepatic bile duct is a benign process but often requires a major operation to definitively diagnose.

Contrast-enhanced ultrasound examination of the gallbladder and bile ducts: A pictorial essay

The gallbladder and bile ducts are usually assessed initially with conventional gray-scale ultrasound (US). Contrast enhanced US (CEUS) is used when a diagnosis cannot be reached with conventional US. CEUS is easy to learn and perform. US contrast agents can be safely administered in patients with renal function impairment. In this pictorial essay the physics, examination technique and indications of CEUS for examining the gallbladder and bile ducts are reviewed. Gallbladder indications include elucidating normal variants, differentiating sludge from neoplastic lesions, benign and malignant pathology, infection, wall rupture and hemobilia. In the biliary tree CEUS is used for studying benign and malignant tumors, including metastases and cholangiocarcinoma, as well as intrabiliary injection.

Heterotopic Pancreas: Histopathologic Features, Imaging Findings, and Complications

Heterotopic pancreas is a congenital anomaly in which pancreatic tissue is anatomically separate from the main gland. The most common locations of this displacement include the upper gastrointestinal tract-specifically, the stomach, duodenum, and proximal jejunum. Less common sites are the esophagus, ileum, Meckel diverticulum, biliary tree, mesentery, and spleen. Uncomplicated heterotopic pancreas is typically asymptomatic, with the lesion being discovered incidentally during an unrelated surgery, during an imaging examination, or at autopsy. The most common computed tomographic appearance of heterotopic pancreas is that of a small oval intramural mass with microlobulated margins and an endoluminal growth pattern. The attenuation and enhancement characteristics of these lesions parallel their histologic composition. Acinus-dominant lesions demonstrate avid homogeneous enhancement after intravenous contrast material administration, whereas duct-dominant lesions are hypovascular and heterogeneous. At magnetic resonance imaging, the heterotopic pancreas is isointense to the orthotopic pancreas, with characteristic T1 hyperintensity and early avid enhancement after intravenous gadolinium-based contrast material administration. Heterotopic pancreatic tissue has a rudimentary ductal system in which an orifice is sometimes visible at imaging as a central umbilication of the lesion. Complications of heterotopic pancreas include pancreatitis, pseudocyst formation, malignant degeneration, gastrointestinal bleeding, bowel obstruction, and intussusception. Certain complications may be erroneously diagnosed as malignancy. Paraduodenal pancreatitis is thought to be due to cystic degeneration of heterotopic pancreatic tissue in the medial wall of the duodenum. Recognizing the characteristic imaging features of heterotopic pancreas aids in differentiating it from cancer and thus in avoiding unnecessary surgery. ^© RSNA, 2017.

The management of a cystic hepatic lesion ruptured in the bile ducts: a case report

Background

Hepatic cystadenoma is a rare benign cystic tumor; it tends to recur after incomplete surgical resection and has malignant potential. We report the case of a patient with a ruptured biliary cystadenoma in the common bile duct that caused diagnostic and therapeutic problems.

Case presentation

A 34-year-old North African woman, admitted for angiocholitis, was operated 2 months before for a hepatic cystic lesion taken for a hydatid cyst compressing her common bile duct. The clinical and the complementary examinations converged toward recurrence of the hydatid cyst for which a surgical resection was decided. Intraoperative findings as well as the histological study of the “membranes” extracted from her common bile duct indicated a hepatic cystadenoma.

Conclusions

The rarity of hepatic cystadenoma and the non-specificity of clinical and imaging signs make diagnosis of hepatic cystadenoma difficult, especially when it is complicated by rupture in the bile ducts; this contributes to a delay in diagnosis and an inadequate therapeutic approach.

Unexpected Presentation of Perianal Granular Cell Tumor in a Young Woman

Granular cell tumors originate from Schwann cells of the soft tissues and are rarely observed in the perianal region. Often, correct diagnosis can be challenging owing to nonspecific clinical symptoms and imaging characteristics, as well as its ability to mimic other malignant lesions histologically. We describe the case of a previously healthy 36-year-old woman who presents with a slow growing, painless lump in her perianal region who underwent surgical excision and was found to have a granular cell tumor on microscopic evaluation. This case highlights the importance for radiologists, pathologists, surgeons, and other health care providers to be aware of this rare neoplasm and consider it in the differential diagnosis when encountering perianal masses.

Spectrum of Xanthogranulomatous Processes in the Abdomen and Pelvis: A Pictorial Review of Infectious, Inflammatory, and Proliferative Responses

OBJECTIVE

Xanthogranulomatous (XG) processes are rare inflammatory conditions with the characteristic pathologic feature of lipid-laden macrophages or histiocyte cells. Imaging findings are nonspecific and can simulate aggressive neoplastic processes. XG processes can be caused by infection, inflammation, histolytic process, or an inherited lysosomal disorder. XG infectious processes are mainly seen in cholecystitis and pyelonephritis, but several other organs can also be involved. Histiocytic processes can be divided into Langerhans and non-Langerhans cell histiocytosis. The non-Langerhans cell histiocytosis entities include Erdheim-Chester disease, Rosai-Dorfman disease, juvenile xanthogranuloma, and hemophagocytic lymphohistiocytosis. The inherited lysosomal disorders resulting in XG processes include Nieman-Pick, Gaucher, and other lysosomal storage disorders.

CONCLUSION

Radiologists need to be able to recognize features of xanthogranulomatous processes to help facilitate patient management.

Cholesterol polyps in the distal common bile duct: a case report

RATIONALE

Cholesterol polyps are rare in the common bile duct and difficult to diagnose.

PATIENT CONCERNS

The small polypoid lesions often go undetected when using routine imaging methods, such as ultrasonography.

DIAGNOSES

We treated a patient with cholesterol polyps in the common bile duct. After failing to detect choleliths using ultrasonography, magnetic resonance cholangiopancreatography revealed mild dilation of the common bile duct. Choledochoscopy was performed during laparoscopic cholecystectomy, which revealed yellowish-white polyps circumferentially distributed across the luminal surface of the distal common bile duct. Histological examination of biopsy specimens indicated cholesterol polyps with characteristic foamy cells.

INTERVENTIONS

The patient was treated with ursodeoxycholic acid, and the number of polyps was found to have been reduced at the 6-week follow-up based on T-tube choledochoscopic examination.

OUTCOMES

Recovery was unremarkable, and the ursodeoxycholic acid treatment was discontinued at the 6-month follow-up.

LESSONS SUBSECTIONS

Our findings suggest that this rare condition can be treated pharmacologically to avoid potential postsurgical complications following resection of the distal common bile duct.

Abdominal manifestations of histiocytic disorders in adults: imaging perspective

Histiocytic disorders (HDs) are a diverse group of diseases characterized by pathologic infiltration of normal tissues by cells of the mononuclear phagocyte system. The spectrum of these diseases ranges from treatable infectious diseases to rapidly progressive, life-threatening conditions. Although they are rare and difficult diagnoses, HDs can be diagnosed with the help of clinical and laboratory analyses, imaging features and tissue biopsy. The clinicopathology and imaging spectrum of select entities belonging to this disorder are presented in this review.

Multimodality Imaging of Liver Infections: Differential Diagnosis and Potential Pitfalls

Imaging plays an important role in the diagnosis, characterization, and management of infectious liver disease. In clinical practice, the main contributions of imaging are in detecting early disease, excluding other entities with a similar presentation, establishing a definitive diagnosis when classic findings are present, and guiding appropriate antimicrobial, interventional, or surgical treatment. The most common imaging features of bacterial, viral, parasitic, and fungal hepatic infections are described, and key imaging and clinical manifestations are reviewed that may be useful to narrow the differential diagnosis and avoid pitfalls in image interpretation. Ultrasonography (US), computed tomography (CT), and magnetic resonance imaging allow accurate detection of most hepatic infections and, in some circumstances, may provide specific signs to identify the underlying pathogen and exclude other entities with similar imaging features. In bacterial and parasitic infections, specific imaging features may be enough to exclude a neoplasm and, occasionally, to identify the underlying infectious agent. US and CT are important means to guide percutaneous aspiration or drainage when needed. In viral infections, imaging is critical to exclude entities that may manifest with similar clinical and laboratory findings. Disseminated fungal infections require early detection at imaging because they can be fatal if not promptly treated. Familiarity with the epidemiology, pathogenesis, clinical manifestations, imaging features, and treatment of hepatic infections can aid in radiologic diagnosis and guide appropriate patient care. (©)RSNA, 2016.

Xanthogranulomatous pancreatitis mimicking a malignant solid tumour

Xanthogranulomatous inflammation, which is known to occur in several viscera, is rarely found to affect the pancreas. We report a case of xanthogranulomatous pancreatitis (XGP) occurring in a 60-year-old man who presented with epigastric pain and vomiting. Physical examination did not reveal any abnormality. Contrast-enhanced CT of the abdomen revealed an ill-defined, heterogeneous mass lesion in the uncinate process of the pancreas, suggestive of malignancy. Whipple's pancreaticoduodenectomy was performed and the final pathological diagnosis was XGP. The patient's postoperative course was uneventful. When a pancreatic mass does not show clinicoradiological features typical of common pancreatic neoplasms, XGP should be considered for a differential diagnosis and duodenum preserving surgery can be considered.

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.

Biliary papillomatosis with malignant transformation: A case report and review of the literature

Biliary papillomatosis is a rare benign tumor that possesses a high potential for malignant transformation, and is frequently misdiagnosed. In the present report, a case of biliary papillomatosis with malignant transformation in a 63-year-old female, with a 19-year history of cholelithiasis, is presented. The patient presented with right epigastric pain and magnetic resonance imaging revealed a diffuse mass in the right liver lobe, which extended through the common bile duct. Definitive preoperative diagnosis was unable to be established; however, following surgical resection of the tumor, a diagnosis of biliary papillomatosis with malignant transformation was confirmed by pathological examination. The patient was followed up seven months later and no recurrence was detected. A supplementary review of previously published literature is additionally presented.

Biliary cystadenoma: an unusual cause of acute pancreatitis and indication for mesohepatectomy

The classic presentation of cystic hepatobiliary lesions is usually nonspecific and often identified incidentally. Here we describe the case of a patient presenting with acute pancreatitis resulting from a large centrally located biliary cystadenoma compressing the pancreas. Determination of the origin of the cystic lesion was difficult on imaging studies. Due to the difficult location of the lesion, a complete surgical resection was achieved with mesohepatectomy and the suspected diagnosis confirmed by pathology. The patient continues to do well 2 years post-op with no signs of recurrence.

Gallbladder splenosis: a hereto unreported mimicker of a gallbladder neoplasm

Splenosis is a completely benign entity that can mimic a primary mass or metastasis. Herein we report the first known case of gallbladder splenosis in a 49-year-old woman with an extensive surgical and medical history. Cross-sectional computed tomography and MRI demonstrated a single mass arising from the gallbladder fundus. Revelation of splenectomy, confirmed to be traumatic from medical records, raised the suspicion for splenosis. The diagnosis was confirmed with a Technecium-99m-labeled heat-damaged blood cell scan, considered the gold-standard for detection of ectopic splenic tissue.