Inflammatory pseudotumor of the liver: radiologic-pathologic correlation

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.

Inflammatory Pseudotumor-Like Follicular Dendritic Cell Sarcoma of the Spleen: Computed Tomography Imaging Characteristics in 5 Patients

OBJECTIVES

The purpose of this study was to retrospectively review the computed tomography (CT) and clinicopathological characteristics of inflammatory pseudotumor (IPT)-like follicular dendritic cell sarcoma (FDCS) of the spleen in 5 patients.

METHODS

Clinical, pathologic, and CT imaging findings of 5 patients with IPT-like FDCS of the spleen were reviewed and analyzed. Computed tomography imaging and pathologic features were compared.

RESULTS

Abdominal unenhanced CT revealed a well-defined hypodense mass in the spleen with complex internal architecture with focal necrosis and/or speckle-strip calcification. On postcontrast CT, slightly delayed enhancement was observed in 5 cases. Four patients had a normalized spleen. The fourth patient had lung metastasis. The fifth patient had 2 relatively small lesions as well as metastases to the spine.

CONCLUSIONS

Computed tomography imaging features of IPT-like FDCS of the spleen are distinctly different from other hypovascular splenic neoplasm; however, the definitive diagnosis requires further confirmation with needle biopsy or surgery. Inflammatory pseudotumor-like FDCS of the spleen should be suggested by using the CT imaging features of the splenic mass with evidence of metastatic disease.

MRI characteristics for the differential diagnosis of benign and malignant small solitary hypovascular hepatic nodules

PURPOSE

To compare the MRI findings of benign and malignant solitary hypovascular hepatic nodules and identify the differentiating features.

MATERIALS AND METHODS

A total of 135 patients with solitary hypovascular hepatic lesions up to 3 cm (mass forming intrahepatic cholangiocarcinoma, n=29; metastases, n=26; inflammatory pseudotumors and solitary necrotic nodule, n=48; and hemangioma, n=32) were assessed. MRI findings were analyzed, and lesions were scored for peripheral and intratumoral appearance and enhancement patterns.

RESULTS

Univariate and multivariate analyses showed that the most common findings for benign lesions were subcapsular, sharp margin, homogeneous, marked high signal on T2WI, mild hyperintensity on T2WI, increasing intensity of peripheral globular enhancement, and persistent central septum-like linear enhancement on delayed phase (P<0.05). An area under the curve of 0.955 was obtained for differentiating malignant from benign nodules using the combined imaging features of ill-defined margins, heterogeneity, decreasing intensity of peripheral rim-like enhancement, and central increasing intensity of patchy enhancement. Interobserver agreement was good, ranging from 0.72 to 1.00.

CONCLUSION

MRI may be a useful noninvasive method for determining whether hypovascular hepatic nodules are malignant or benign.

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.

Capsular retraction: an uncommon imaging finding in hepatic inflammatory pseudotumour

Capsular retraction is an infrequent but characteristic feature of malignant liver lesions such as hepatic metastases and intrahepatic cholangiocarcinoma. Rarely, this finding may be observed in association with benign lesions, such as atypical haemangiomas. Capsular retraction has not previously been reported in association with hepatic inflammatory pseudotumour (IPT). Hepatic IPT is an uncommon benign hepatic lesion with a good clinical prognosis. In this report, we discuss the case of a 48-year-old woman with capsular retraction secondary to multifocal hepatic inflammatory IPTs.

Imaging findings of head and neck inflammatory pseudotumor

OBJECTIVE

The purpose of this article is to describe imaging features of head and neck inflammatory pseudotumor in the brain, orbit, sinonasal cavity, temporal bone or skull base, and other rare locations.

CONCLUSION

Although the 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.

[Diagnosis and differential diagnosis of benign liver tumors and tumor-like lesions]

Benign liver tumors and tumor-like lesions cover a broad spectrum of differential diagnoses, varying from dysontogenetic cysts to pseudolesions. Focal nodular hyperplasia, adenoma and regenerating nodules play a major role in clinical practice. Based on imaging findings, these lesions can be classified as cystic or solid, solitary or multiple, and hyper- or hypovascular. Haemangioma, FNH, steroid-associated adenoma, cystadenoma and echinococcus cysts can be reliably diagnosed using imaging techniques. The same is true for pseudolesions, which are found in particular on dynamic computed tomography. Other entities such as adenoma in cirrhotic livers, angiomyolipoma, regenerating nodules or Echinococcus alveolaris cannot be safely diagnosed by imaging and require biopsy. Morphological and functional characteristics of the most common lesions in the different imaging modalities will be discussed. Where possible, a diagnostic strategy will be presented.

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.

Imaging of focal hepatic lesions: self-assessment module

Focal hepatic lesions are one of the diagnostic challenges in daily practice. This article focuses on the imaging features of focal hepatic lesions on different imaging modalities, including sonography, CT, and MRI.

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.

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.

[Hepatic tuberculosis: case report of pseudotumoral form]

Inflammatory pseudo-tumors of the liver are rare and difficult to diagnose, mimicking malignant tumors. We report a patient, 42 year old with hepatic pseudo-tumor who was suspected to have pseudotumoral hepatic tuberculosis without immunodepression and treated by major hepatic surgery because no sure diagnosis. Therapeutic approach of hepatic inflammatory pseudotumors is often medical and surgical and may need major hepatic surgery in case of sure etiologic diagnosis.

CT and MRI appearances of inflammatory pseudotumour of the cervical lymph nodes

Inflammatory pseudotumour (IPT), also known as plasma cell granuloma and inflammatory myofibroblastic tumour, is a rare cause of benign cervical lymphadenopathy which mimics malignant causes of cervical lymphadenopathy. The imaging features of IPT affecting the cervical lymph nodes have not previously been described. We present cross sectional imaging in a case of IPT occurring in a 42-year-old African-Caribbean man, from his initial presentation to a subsequent spontaneous reduction in the extent of lymphadenopathy.

Inflammatory pseudotumor of the liver in a patient with early gastric cancer: CT-histopathological correlation

A case of inflammatory pseudotumor (IPT) of the liver associated with early gastric cancer is reported. Intravenous contrast-enhanced computed tomography (CT) showed a large, irregularly shaped mass lesion in the left lobe of the liver. The lesion was characterized by peripheral rim-like or septal enhancement and an internal low density area in the delayed phase. The gastric cancer was a papillary adenocarcinoma limited to the mucosa. The resected liver tumor measured 5.5 x 5.0 x 4.0 cm, and its cut surface revealed a well-circumscribed mass divided into lobules by fibrous tissue. Histologically the mass was composed of fibrous areas and cellular areas, and the cellular areas consisted of fascicles of plump spindle cells intermingled with varying numbers of plasma cells, lymphocytes and histiocytes. Thus, the higher attenuation on the enhanced CT scan corresponded to the areas of intense fibrosis, and the areas of lower attenuation corresponded to the predominantly cellular areas. The CT findings of delayed peripheral rim-like or septal enhancement of the hepatic tumor may be a specific finding 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.

Inflammatory pseudotumor of the liver: demographics, diagnosis, and the case for nonoperative management

BACKGROUND

Inflammatory pseudotumor of the liver (IPL) is an unusual tumor-like condition that is becoming recognized as an important differential diagnosis in the patient presenting with liver masses. This report describes six cases of IPL.

STUDY DESIGN

Clinical, diagnostic, pathologic, and followup data were collected prospectively on six patients presenting to a specialist hepatobiliary unit.

RESULTS

Six patients with IPL presented over a 2-year period. Median age was 35 years (range 2 to 79 years) and five patients were men. Three patients were Polynesian (Tongan and Samoan) and one was New Zealand Maori. Five patients presented with nonspecific symptoms (fever, arthralgia, myalgia) and IPL was an incidental finding in one patient. At presentation, four patients had elevated white cell counts, and five patients had abnormal liver function tests with elevations in alkaline phosphotase and gamma-glutamyl transferase the most commonly seen. Carcinogenic embryonic antigen and alpha fetoprotein were normal in all patients, although one was a known hepatitis B carrier. In all cases of IPL, diagnosis was made on core biopsy of the liver lesions and all patients were managed nonoperatively with complete resolution of the tumors. Two patients had marked reduction in systemic symptoms (fever and pain) from a short course of oral steroids.

CONCLUSIONS

IPL appears to be a relatively common problem in Maori and Polynesians. Recognition and differentiation of this condition from malignant liver lesions are important to avoid unnecessary surgery.

[Inflammatory pseudotumors of the liver]

Inflammatory pseudotumours are very rare with hardly over hundred cases reported in literature. The disease is rare in children. The tumour is usually solitary, rarely multifocal. We report on two women old 48 and 49 years. One had a solitary tumour, and the other had four multifocal inflammatory pseudotumours which were surgically removed. Preoperatively both patients had pain, loss in weight, the one had attacks of low grade temperature and the other nausea and general malaise. One patient had leucocytosis. After surgery both patients stayed symptom free with normal laboratory and ultrasonographic findings 6 and 50 months respectively.

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.

Inflammatory pseudotumor of the liver in patients with recurrent pyogenic cholangitis: CT-histopathologic correlation

PURPOSE

To correlate computed tomographic (CT) features of inflammatory pseudotumors of the liver with histopathologic results in patients with recurrent pyogenic cholangitis.

MATERIALS AND METHODS

CT features of 13 cases of inflammatory hepatic pseudotumor in 10 patients with recurrent pyogenic cholangitis were reviewed. Diagnosis was made by means of surgical resection in all patients. CT scans were analyzed for the appearance of masses and ancillary findings in correlation with the histopathologic findings in each resected specimen.

RESULTS

The masses were 2.0-7.0 cm (mean, 3.5 cm). At nonenhanced CT, the masses appeared as ill-defined, hypoattenuating lesions. At contrast material-enhanced CT, the masses exhibited central hypoattenuating areas with an iso- or hyperattenuating thickened periphery in four cases and a multiseptate appearance with hyperattenuating internal septa and periphery in nine cases. CT-histopathologic correlation showed that the central hypoattenuating area indicated the presence of chronic inflammatory infiltrates with foamy histiocytes, plasmacytes, and lymphocytes, while iso- or hyperattenuating areas in the periphery and internal septa of the mass represented fibroblastic proliferation. All patients had CT features of recurrent pyogenic cholangitis, such as hepatolithiasis, intrahepatic duct stricture and dilatation, common bile duct calculi, pneumobilia, or parenchymal atrophy.

CONCLUSION

Although CT features are not specific, inflammatory pseudotumor should be included in the differential diagnosis in patients with recurrent pyogenic cholangitis and a hepatic mass detected at CT.

Imaging of follicular dendritic cell tumours of the liver

Follicular dendritic cell tumour of the liver is a recently recognized entity. To date, only two cases have been described, both in the pathology literature. Histologically, it resembles an inflammatory pseudotumour and immunohistochemical and ultrastructural studies are required for its diagnosis. The ultrasound, computed tomography and angiographic features of two cases of follicular dendritic cell tumour of the liver are described in detail. One of the patients had multiple recurrences of this tumour. The imaging features are very similar to those of hepatocellular carcinoma. As follicular dendritic cell tumour is considered to be of low-grade malignant potential, in contrast to the dismal prognosis for hepatocellular carcinoma, it is important to be able to accurately distinguish between the two types of tumour prior to initiating definitive therapy.

Inflammatory pseudotumor of the liver: MRI with mangafodipir trisodium

Inflammatory pseudotumor of the liver is a rare benign mass that is often misdiagnosed as hepatocellular carcinoma at preoperative imaging. We report a case of inflammatory pseudotumor of the liver with special emphasis on the appearance at MRI after administration of mangafodipir trisodium. On T1-weighted images the lesion was slightly hypointense relative to the liver, and on T2-weighted images it was isointense with a hyperintense capsule. No tumor enhancement was seen on T1-weighted images after administration of mangafodipir trisodium. MRI with mangafodipir trisodium might help to distinguish inflammatory pseudotumor of the liver from hepatocellular carcinoma.