Inflammatory pseudotumor of the liver: MRI with mangafodipir trisodium

Immunoglobulin G4-Negative Inflammatory Pseudotumors of the Pancreas

Inflammatory pseudotumor (IPT) can occur in any organ, but rarely shows pancreatic involvement. While surgical excision has been recommended as the primary treatment for IPT of the pancreas in the past, some authors suggest observation while medical management often results in regression. Corticosteroids, nonsteroidal anti-inflammatory drugs and immunosuppressive therapy have been used to treat IPTs. Spontaneous regression has also been reported in IPT managed without surgical intervention. A 62-year-old female was evaluated for worsening abdominal pain and a mass in the neck of the pancreas that was identified on ultrasound. Further imaging with magnetic resonance imaging revealed a pancreatic mass with dilated pancreatic duct and an atrophic parenchyma of the pancreatic neck. Her serum tumor markers were not elevated. As this lesion appeared to be resectable pancreatic cancer based on cross-sectional imaging, no biopsy was performed prior to surgical resection. Distal pancreatectomy and splenectomy was recommended and the patient desired to proceed. Her recovery was uneventful with no postoperative complications, including pancreatic fistula. Final pathology revealed a lesion consistent with the diagnosis of immunoglobulin G4 (IgG4)-negative IPT without neoplasm. IPT of the pancreas is a difficult entity to diagnose and treat due to clinical and imaging characteristics closely resembling pancreatic adenocarcinoma. Biopsy with immunohistochemical analysis can be useful in diagnosing IPT; however, symptomatic lesions and concerning findings on cross-sectional imaging may warrant more definitive surgical intervention.

A Case of Renal Inflammatory Pseudotumor Leading to Nephrectomy

Inflammatory pseudotumor (IPT) of the kidney is a rare benign disorder with unknown etiology. In IPT patients, some nonspecific symptoms might present, such as fever, hematuria, and back pain. As it can appear on computed tomography and magnetic resonance imaging as a hypovascular mass with surrounding fat stranding, IPT can be misdiagnosed as a primary tumor. Since the clinical symptoms, radiographic features, and preoperative findings can be inconsistent, it is imperative to confirm IPT based on histopathological assessment. In the present study, we describe a case of renal IPT in a 13-year-old girl. The patient was treated with nephrectomy of the right kidney since the preoperative diagnosis was renal carcinoma. Pathological examination revealed an IPT. This article emphasizes the importance of preoperative definitive diagnosis in avoiding unnecessary nephrectomy.

Overlooked and Challenging Encounters–Inflammatory Pseudotumors in the Abdomen and Pelvis: A Pictorial Essay

Inflammatory pseudotumors (IPTs) are uncommon, mass-forming lesions, predominantly involving the lung and orbit. Although the incidence of IPTs is rare in the abdomen and pelvis, they can be encountered as enhancing, soft-tissue lesions, mimicking malignancy or fibrosclerosing disease. Generally, they exhibit a wide range of nonspecific imaging features in various organs. Preoperative imaging diagnosis of IPTs in appropriate clinical settings may help determine proper patient management. In this article, we review radiologic findings of IPTs in the abdominopelvic cavity, including the liver, spleen, kidney, gastrointestinal tract, mesentery, pelvis, and retroperitoneum.

Hepatic inflammatory pseudotumor presenting in an 8-year-old boy: A case report and review of literature

Hepatic inflammatory pseudotumors are uncommon benign lesions. Accurately diagnosing hepatic inflammatory pseudotumor can be very challenging because the clinical presentation and radiological appearances are nonspecific and cannot be certainly distinguished from malignant neoplastic processes. Herein, we present a case of hepatic IPT in an 8-year-old boy who presented to clinic with a 3-mo history of a tender hepatic mass, fever of unknown origin, and 9-kg weight loss. The physical examination was notable for tender hepatomegaly. Laboratory investigations were notable for a normal hepatic profile and elevated erythrocyte sedimentation rate and C-reactive protein. A T2-attenuated magnetic resonance imaging scan of the abdomen showed a 4.7 cm × 4.7 cm × 6.6 cm, contrast-enhancing, hyper-intense, well-defined lesion involving the right hepatic lobe. In view of the unremitting symptoms, tender hepatomegaly, thrombosed right hepatic vein, nonspecific radiological findings, and high suspicion of a deep-seated underlying infection or malignancy, a right hepatic lobectomy was recommended. Microscopically, the hepatic lesion exhibited a mixture of inflammatory cells (histiocytes, plasma cells, mature lymphocytes, and occasional multinucleated giant cells) in a background of dense fibrous tissue. Immunohistochemically, the cells stained negative for SMA, ALK-1, CD-21 and CD-23, diffusely positive for CD-68, and focally positive for IgG4. The final histopathological diagnosis was consistent with hepatic IPT. At the postoperative 4-mo follow-up, the patient was asymptomatic without radiological evidence of recurrence.

Inflammatory pseudotumor of the liver: a rare case of recurrence following surgical resection

Inflammatory pseudotumor (IPT) of the liver is a rare, benign lesion that may be mistaken for malignancy. IPTs are difficult to diagnose due to non-specific clinical, laboratory and imaging features. We report the case of a 38-year old Asian male who presented with fatigue, weight loss and hepatomegaly. He was found to have a large hepatic IPT and underwent surgical resection; approximately two and a half years later, he developed acute cholangitis secondary to IPT recurrence. We present the imaging features of hepatic IPT using ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI). We also review the literature on the diagnosis and management of this disease. The unique features of this case include the IPT's recurrence following surgical resection, large size and multiple modalities presented.

Adrenal inflammatory myofibroblastic tumour

A rare case of large adrenal mass which was non-functioning is presented. It is difficult to make preoperative diagnosis in these cases as the imaging findings are non-specific. Radical excision is mandatory as preoperative malignancy cannot be ruled out.

Inflammatory pseudotumor of the liver associated with Crohn's disease

Inflammatory liver pseudotumor is a rare entity. Associations with several inflammatory conditions were reported but association with inflammatory bowel disease is unusual. We report the case of liver inflammatory pseudotumor occurring in the course of Crohn's disease in a 23-year-old woman and treated conservatively.

Inflammatory pseudotumors of the liver: experience of a specialist surgical unit

BACKGROUND AND AIM

To present the experience in management of inflammatory liver pseudotumors from a specialist surgical unit and to review the medical literature on this rare manifestation.

METHODS

Between 1995 and 2008, four patients were identified with this type of tumor from a total of 108 resected benign liver lesions at the Royal Infirmary of Edinburgh, Scotland UK. Two patients presented with liver abscesses, one with liver cystadenoma, and one with hilar cholangiocarcinoma. All four underwent some type of hepatectomy. We report these cases and review the literature.

RESULTS

All four patients survived the operation with some morbidity.

CONCLUSIONS

Inflammatory liver pseudotumors are a difficult entity to identify. Resection should be considered because it may be impossible to rule out malignancy by other means.

Inflammatory pseudotumours of the liver: a spectrum of presentation and management options

PURPOSE

To review the current management options in inflammatory pseudotumours via analysis of ten cases from this unit the largest experience of this pathology in a Western series. To assess the medical and operative options available for this condition and the varying outcomes and the lessons learned in this unit over the time period.

RESULTS

Data from the ten cases were analysed and a comprehensive review of the published literature to date has detailed 128 case reports with 215 cases of inflammatory pseudotumour of the liver. Data analysed included patient demographics, diagnostic modalities, details of treatment and eventual outcome. The data was tabulated using an Excel spreadsheet (Microsoft Excel 2004 for Mac 2004.Version 11.0). Categorical variables were compared using Pearson's chi(2) test and p values <0.05 were defined as statistically significant. Statistical analysis was performed using SPSS for Windows (Version 9.0, SPSS Inc., Chicago, IL).

CONCLUSION

Emphasis is placed on a preferred medical management initially for this tumour with a good prognosis coupled with regular follow up. There may be a need for surgical resection cases where diagnosis is unclear or the patient is not responding to medical treatment with progression of disease or symptoms.

Inflammatory pseudotumor (myoblastic tumor) of the genitourinary tract

OBJECTIVE

The purpose of this article is to describe imaging features of the following genitourinary tract locations that can involve inflammatory pseudotumor: kidney, adrenal gland, retroperitoneum or pelvis, bladder, and other rare locations.

CONCLUSION

Although definite radiologic differentiation from malignancy is not clearly possible, we suggest that familiarity with the manifestations of inflammatory pseudotumor can help avoid unnecessary radical surgery before histopathologic proof of malignancy is obtained.

Unusual benign focal liver lesions: findings on real-time contrast-enhanced sonography

OBJECTIVE

This presentation aims to provide an overview of the manifestations of some unusual benign focal liver lesions (FLLs) on low-acoustic power contrast-enhanced sonography (CES) with a sulfur hexafluoride contrast agent.

METHODS

The patients were selected retrospectively from 2209 cases with FLLs who had undergone CES examinations for characterization during the past 3 years. The pathologic examinations proved that they were intrahepatic biliary cystadenoma (n = 1), angiomyolipoma (AML; n = 4), lipoma (n = 1), biliary epithelial dysplasia (n = 1), a fungal inflammatory mass (n = 1), tuberculoma (n = 2), an inflammatory pseudotumor (n = 7), sarcoidosis (n = 1), solitary necrotic nodules (n = 2), peliosis hepatis (n = 2), and focal fibrosis after surgery (n = 4).

RESULTS

Contrast-enhanced sonography was beneficial in leading to a diagnosis of benignity for some lesions showing hyperenhancement during the arterial phase and sustained enhancement during the portal or late phase, such as liver AML and lipoma. The benign nature of other lesions showing no enhancement during all phases, such as solitary necrotic nodules and focal fibrosis, was also suggestible. On the other hand, for those lesions showing hyperenhancement, isoenhancement, or hypoenhancement during the arterial phase and hypoenhancement during the late phase, including intrahepatic biliary cystadenoma, biliary epithelial dysplasia, infected liver diseases, the inflammatory pseudotumor, sarcoidosis, and peliosis hepatis, the differential diagnosis between benignity and malignancy was difficult, and pathologic tests were mandatory.

CONCLUSIONS

The CES features of unusual benign FLLs may enrich knowledge when performing CES examinations for characterization and may provide clues for a specific diagnosis of an individual lesion such as liver AML.

Inflammatory myofibroblastic tumors in the liver: MRI of two immunohistochemically-verified cases

In immunohistochemically-proven hepatic inflammatory myofibroblastic tumors, MRI revealed layered patterns of contrast enhancement during dynamic imaging, consisting of outer hypovascular rind and inner hypervascular stroma and mimicking the imaging features of pyogenic organized abscess with deficient central necrosis in four lesions in two patients. For the outer hypovascular rind, T2-weighted images showed hyperintensity, suggesting immature fibrosis corresponding to the area of arterial hypovascularity and delayed contrast enhancement. The patients' favorable clinical course and imaging findings reflected the benign nature of these lesions, from an infectious origin, despite the phenotypic expression of myofibroblastic proliferation in the hypervascular stroma containing chronic inflammatory cells.

Imagerie des pseudo-tumeurs inflammatoires hépatiques

PURPOSE

To describe the imaging features of inflammatory pseudotumors of the liver.

INTRODUCTION

Inflammatory pseudotumors of the liver are rare benign lesions that may simulate malignancy on imaging studies. Diagnosis is most frequently confirmed after surgical resection of the lesion.

MATERIALS AND METHODS

Retrospective study from 1998 to 2006 of histologically proven cases of inflammatory pseudotumors of the liver. A combination of the following imaging modalities were utilized: US, contrast enhanced US, helical CT and MRI.

RESULTS

A total of seven lesions (mean diameter of 61.4 mm) were detected in 6 patients (mean age of 66 years). Clinical and laboratory results were non-specific. The following imaging studies were available: US in 5 cases, including one with contrast material, CT in 5 cases and MRI in 3 cases. All tumors were hypoechoic on US, with no enhancement after injection of Levovist. The tumors were generally hypodense on noncontrast CT and enhancement, when present, was delayed and moderate. On MRI, the tumors were iso- or slightly hyperintense on T2W images and iso- or slightly hypointense on T1W images with subtle peripheral enhancement on delayed imaging.

CONCLUSION

The differential diagnosis of inflammatory pseudotumor of the liver should be known to radiologists and could be suggested in a clinical context of chronic inflammatory process in patients with non-specific liver mass showing imaging features of partial fibrosis with delayed enhancement.

Spontaneous regression of inflammatory pseudotumor of the liver: report of three cases

Inflammatory pseudotumor (IPT) of the liver is a rare benign hepatic lesion that sometimes mimics malignant tumors. An accurate diagnosis of IPT is important to avoid unnecessary surgery. We herein report three cases of IPT of the liver that spontaneously regressed and were successfully diagnosed without a surgical resection. Malignant tumors were initially suspected based on the initial imaging findings, including ultrasonography, computed tomography (CT), and magnetic resonance imaging. In particular, a delayed enhancement in the periphery of the masses was observed on dynamic CT scans, similar to the imaging results for metastatic tumors or intrahepatic cholangiocarcinomas. The serum levels of C-reactive protein were elevated in all three patients (6.6, 3.4, and 1.5 mg/dl), while the serum levels of tumor markers were almost within the normal ranges (carcinoembryonic antigen, <5 ng/ml; carbohydrate antigen 19-9, 201, 3, and 14 U/ml). Serial repeated imaging studies over the course of a month showed the spontaneous regression of the hepatic tumors, thus enabling us to make a diagnosis of IPT without a surgical resection. A percutaneous biopsy confirmed the histology in one case. The regression of tumors on repeated images should play a key role in making an accurate diagnosis of IPT.

Inflammatory myofibroblastic tumor of the hepatobiliary system: report of MR imaging appearance in four patients

The purpose of this report is to describe the magnetic resonance (MR) imaging features of hepatic inflammatory myofibroblastic tumor (IMT). Two observers retrospectively analyzed images from six MR imaging examinations in four consecutive patients. Tumor location, size, extent, morphology, and number; signal intensity on nonenhanced images; enhancement pattern on serial gadolinium-enhanced images; duct wall thickness; and presence of biliary dilatation, vascular invasion, and lymphadenopathy were assessed. MR imaging findings were compared with histologic findings. On MR images, hepatic IMT manifested as a mass-like lesion in two patients and an area of periportal soft-tissue infiltration in three; one patient had both patterns. Because periportal infiltration is a common feature in both IMT and other malignant tumors of the porta hepatis, histologic examination should be considered before diagnosis and treatment.

Efficacy and safety of mangafodipir trisodium (MnDPDP) injection for hepatic MRI in adults: results of the U.S. Multicenter phase III clinical trials. Efficacy of early imaging

The efficacy of contrast-enhanced magnetic resonance imaging (MRI) for detecting and characterizing, or excluding, hepatic masses was assessed in 404 patients, following the intravenous administration of mangafodipir trisodium (MnDPDP) injection, a hepatic MRI contrast agent. An initial contrast-enhanced computed tomography (CT) examination was followed by unenhanced MRI, injection of MnDPDP (5 micromol/kg IV), and enhanced MRI at 15 minutes post injection. Agreement of the radiologic diagnoses with the patients' final diagnoses was higher for enhanced MRI and for the combined unenhanced and enhanced MRI evaluations than for unenhanced MRI alone or enhanced CT using the clinical diagnosis as the gold standard. Mangafodipir-enhanced MRI uniquely provided additional diagnostic information in 48% of the patients, and patient management was consequently altered in 6% of the patients. MnDPDP-enhanced MRI was comparable or superior to unenhanced MRI and enhanced CT for the detection, classification, and diagnosis of focal liver lesions in patients with known or suspected focal liver disease.

Sequential use of gadolinium chelate and mangafodipir trisodium for the assessment of focal liver lesions: initial observations

The purpose of this study was to assess the feasibility of sequential administration of 2 different MR imaging contrast agents using a single visit protocol to image focal liver abnormalities. Twenty-one patients with known or suspected liver lesions were included in the study. All patients received a bolus intravenous injection of gadolinium chelate (Gd) and dynamically enhanced imaging performed. The patients then received an injection of mangafodipir trisodium (Mn) contrast and a second scan performed with an average delay of 62 min after the Gd bolus injection. The images were evaluated to determine the appearance of liver lesions after administration of each contrast agent, and for evidence of prior Gd administration adversely affecting evaluation of images acquired after Mn administration. Focal liver lesions were present in 19 patients, including 8 with liver metastases, 1 with liver lymphoma, 6 with hemangiomas, 3 with focal nodular hyperplasia (FNH), and 1 with hepatic abscess. In 2 other patients no liver lesions were identified in either the post-Gd or post-Gd-post-Mn scans. All malignant lesions identified on the post-Gd scan were also identified on post-Gd-post-Mn scans. Although the potential benefit for increasing detection sensitivity for hepatic metastases was not demonstrated, this is a preliminary series. This study does demonstrate the practicality for use a single visit sequential Gd-Mn protocol described here, with possible application of this technique for further assessment of the utility of combining Gd and Mn for detection of liver metastases.

Radiologic findings of renal inflammatory pseudotumor: a case report

Renal inflammatory pseudotumor is a very rare benign condition of unknown etiology characterized by proliferative myofibroblasts, fibroblasts, histiocytes, and plasma cells. In the case we report, the lesion appeared on contrast-enhanced power Doppler US images as a well-defined hypoechoic mass with intratumoral vascularity, and on CT as a low-attenuated mass. Differentiation from malignant renal neoplasms was not possible.