Diagnosis of inflammatory pseudotumor of the liver: value of CT

Clinicopathological features and post-resection outcomes of inflammatory pseudotumor of the liver

Backgrounds/Aims

Hepatic inflammatory pseudotumor (HIPT) is a rare disease characterized by chronic infiltration of inflammatory cells and area of fibrosis. The objective of this retrospective observational study was to investigate clinicopathological features and outcomes of patients who underwent hepatic resection (HR) for HIPT.

Methods

From 2009 to 2018, seven patients with HIPT underwent HR, accounting for 0.06% of 11,979 adults who underwent HR at our center.

Results

These seven patients included five men and two women. Their mean age was 62.3±11.6 years. In four patients with hepatitis B virus (HBV)-associated liver cirrhosis or chronic hepatitis, liver masses were suspected of hepatocellular carcinoma (HCC) or combined HCC-cholangiocarcinoma based on imaging studies. In three patients without HBV infection, two patients were suspected of HCC, for whom liver biopsy was not performed. One patient was suspected of liver abscess or HIPT, for whom percutaneous liver biopsy was performed and the mass was diagnosed with HIPT. However, this patient underwent HR owing to abdominal pain. No patient presented with abnormally elevated levels of alpha-fetoprotein, protein induced by vitamin K absence or antagonist-II, or CA19-9. During a mean follow-up period of 76.4±34.8 months, no patient experienced recurrence of HIPT.

Conclusions

HIPT, a rare form of liver disease, is often misdiagnosed as malignant liver tumor. Active histological diagnosis is warranted for patients with suspected HIPT to avoid unnecessary operation. HR can be indicated in case of diagnostic ambiguity of HIPT or under a clinical diagnosis of malignant liver tumor.

Inflammatory Myofibroblastic Tumor of the Liver Mimicking Metastasis on 18F-FDG PET/CT

A 62-year-old woman with history of stage III endometrial cancer was found to have a small enhancing liver lesion on follow-up abdominal CT and MRI, suspicious for metastasis. Subsequent F-FDG PET/CT was performed, demonstrating intense uptake within the liver lesion, consistent with metastasis. Subsequently, laparoscopic wedge liver lesion resection was performed. Histopathologic examination confirmed the diagnosis of inflammatory myofibroblastic tumor (IMT) with predominant inflammatory cells. Although solitary liver IMTs are rare occurrences with imaging features overlapping with malignancy, IMT should be considered in the differential diagnosis of suspicious liver lesions, especially when the pattern of spread is unusual.

Inflammatory pseudotumors of the liver: Importance of a multimodal approach with the insistance of needle biopsy

CONTEXT:

Inflammatory pseudotumor (IPT) of the liver is a rare, tumor-like lesion that is considered to be biologically benign but often mimics malignancy.

AIMS:

The aim of the study was construe clinicopathological features, imaging findings, differential diagnosis, management, and follow-up of IPT involving the liver.

SETTINGS AND DESIGN:

It is a retrospective study.

SUBJECTS AND METHODS:

Cases included were of IPT, diagnosed on histopathology, at our center from June 2009 to December 2016. Details studied were clinical presentation, imaging studies, laboratory investigations, pathological features, treatment, and follow-up of the cases and compared with reports in the literature.

RESULTS:

A total of cases of IPT included were 17. The age of the patients ranged from 21 to 62 years. Common presenting features were intermittent fever, upper abdominal pain, and weight loss. Radiological diagnosis varied from neoplastic (13) to infectious etiologies (4), with hepatocellular carcinoma being the most common differential (7/17). Laboratory investigations revealed leukocytosis, hyperbilirubinemia, raised transaminases, and raised serum alkaline phosphatase. Core biopsy of a tumor conceded increased fibrosis along with mixed inflammatory cell infiltrates. Eleven cases were managed conservatively and showed regression or complete recovery. Six patients underwent surgical resection. None of these had any recurrence in median follow-up of 22 months.

CONCLUSIONS:

IPT of the liver can masquerade as a fatality, either primary or metastatic. It will be well managed with conservative modalities and can avoid redundant hepatectomy, reserved for complicated cases. For this intent, accurate preoperative diagnosis is the requisite, and needle biopsy with or without fine-needle aspiration cytology plays as a significant rescuer in this field.

An Enigmatic Liver Mass in a Child

Hepatic space occupying lesions in childhood are a diagnostic challenge, as they are caused by a variety of malignant and nonmalignant disorders with a different prognosis and, of course, treatment. They are often misdiagnosed or diagnosed only after surgical resection. A 14-year-old boy presented with abdominal pain, evening-rise fever with loss of appetite and weight. The patient also developed jaundice after 2 months of above symptoms. Ultrasound of the abdomen showed an irregular infiltrative mass in segment IV of the liver. Gadobenate disodium magnetic resonance imaging done showed T1 hypointense and T2 hyperintense lesions in segment VIII of the liver with extension into porta with delayed enhancement suggestive of fibrous tumor. Liver biopsy showed extensive liver parenchymal fibrosis with a mixed inflammatory infiltrate with eosinophils. Bacterial, tubercular, and fungal culture of liver biopsy were negative. Although serum IgG4 levels were 7.88 g/L (N =1.9 g/L), IgG4 staining of liver biopsy was negative. The patient was started on prednisolone 1 mg/kg considering the diagnosis of inflammatory pseudotumor (IPT). Twenty days after starting the steroid, mass lesions were converted into multicystic abscess requiring antibiotics and pigtail drainage. On follow-up, patient had improved symptoms with mass lesions turned into small-sized abscess cavity. Hepatic IPTs are difficult to differentiate from malignant tumors, as they are rare and can have variable imaging findings. To avoid inadvertent surgery, histological confirmation of the hepatic mass is essential. Steroids should be used with caution with close follow-up to prevent iatrogenic complications, such as a chronic liver abscess.

Hepatic Inflammatory Pseudotumor Protruding from the Liver Surface and Directly Penetrating the Colon

A 69-year-old man was diagnosed with a liver abscess and received antibiotics at a local hospital. He was referred to our hospital due to a persistent fever. He had hepatic masses protruding from the liver surface toward the transverse colon. We reached a diagnosis of inflammatory pseudotumor (IPT) by a percutaneous liver biopsy. Colonoscopy showed direct invasion of IPT to the colon. His condition improved by the intravenous administration of antibiotics. Hepatic IPT is often misdiagnosed as a malignant tumor. We should consider IPT when we encounter hepatic tumors, and a percutaneous liver biopsy is useful for avoiding unnecessary excessive treatments.

Spectrum of Pitfalls, Pseudolesions, and Misdiagnoses in Noncirrhotic Liver

OBJECTIVE

The purpose of this article is to illustrate the various pitfalls, mimics, and atypical features that can lead to inaccurate diagnosis of focal lesions in a noncirrhotic liver. The content includes relevant pathogenesis and background as well as specific clues that can be used to reach an accurate diagnosis.

CONCLUSION

When assessing focal hepatic lesions, it is important to avoid pitfalls and misdiagnoses that can alter the management plan. Helpful strategies for avoiding pitfalls include paying close attention to the clinical history of the patient, carefully evaluating all of the available imaging studies, and being aware of the various radiologic mimics.

Successful Stem Cell Transplantation in a Patient with Pretransplant Hepatic Inflammatory Pseudotumour

Inflammatory pseudotumours (IPT) are rare benign neoplasms of unknown aetiology. We present a case of hepatic IPT which was incidentally discovered in a patient with relapsed B-acute lymphoblastic leukaemia (B-ALL) undergoing pretransplant workup. After investigation to exclude an infective cause she underwent a reduced intensity conditioning stem cell transplant (SCT) successfully and currently remains well and in remission. On repeat liver MRI after SCT, the IPT was seen to be resolving. To the best of our knowledge this is the first report of an adult patient with hepatic IPT successfully undergoing SCT. The reduction in size of the IPT after SCT also suggests an inflammatory rather than an infective aetiology for IPT.

Immunoglobulin G4-related hepatic inflammatory pseudotumor invading the abdominal wall

A 50-year-old woman presented with epigastralgia. Computed tomography (CT) of the abdomen revealed a 6-cm well-enhanced mass extending from the left lobe of the liver to the abdominal wall, suggestive of cholangiocarcinoma. Liver and skin mass biopsies did not provide evidence of hepatic malignancy but were rich in plasma cells and sclerotic lesions. Subsequent detection of elevated serum immunoglobulin G4 (IgG4) led to a diagnosis IgG4-related inflammatory pseudotumor (IPT) of the liver. Treatment with systemic corticosteroids resulted in rapid clinical improvement. This case is the first report of an IgG4-related hepatic IPT invading the abdominal wall.

Necrotizing granulomatous inflammation of the liver

A 73-year-old patient with necrotizing granulomatous inflammation of the liver is presented. The computed tomography demonstrated 2 hypodense tumors with progressive enhancement in the liver. They became nearly isodense to the normal hepatic parenchyma on the delayed phase.

Primary mesenchymal liver tumors: radiological spectrum, differential diagnosis, and pathologic correlation

With the exception of hemangioma, benign or malignant primary mesenchymal tumors of the liver are seldom encountered. The aim of this review was to discuss the clinical, histopathological, and imaging features of liver hemangiomas (cavernous, capillary, and sclerosed types), liver lipoma, angiomyolipoma, mesenchymal hamartoma, neurofibroma, infantile hemangioendothelioma, epithelioid hemangioendothelioma, myofibroblastoma, angiosarcoma, malignant fibrous histiocytoma, undifferentiated embryonal sarcoma, and nested stromal tumor. In most of these rare liver tumors, radiological findings obtained by cross-sectional imaging may reflect the characteristic pathologic features required for differential diagnosis; however, definitive diagnosis should be confirmed using histopathological examination.

Inflammatory pseudotumor of the liver occurring during the course of hepatitis C virus-related hepatocellular carcinoma treatment: A case report

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Occurrence of IPT of the liver during the course of HCC treatment is rare.

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IPT of the liver may resemble moderately differentiated HCC on dynamic enhanced CT.

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Hepatic IPT may be associated with latent inflammatory reactions to HCV activity despite negative HCV-RNA.

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Hepatectomy should be considered for a hepatic lesion suspected as HCC but may be IPT.

Introduction

Inflammatory pseudotumor (IPT) of the liver is a rare and benign disease that has a good prognosis. It is often difficult to distinguish IPT from hepatic malignancies, such as hepatocellular carcinoma (HCC), because specific clinical symptoms are absent and the diseases’ radiological findings can be similar. IPT is particularly difficult to distinguish from HCC in livers with hepatitis C virus (HCV)-related cirrhosis. We report a case of IPT of the liver that mimicked HCV-related HCC recurrence.

Presentation of case

A 78-year-old asymptomatic Japanese man who had undergone hepatectomy for HCV-related HCCs (moderately differentiated type) in segments 7 and 5 four and a half years previously was referred to our hospital for treatment of a 30-mm enhanced tumor in segment 5 (a typical HCC pattern). The tumor was identified via abdominal dynamic computed tomography (CT) and CT with hepatic arteriography and arterial portography. Thereafter, liver segmentectomy 5 was performed, and the histopathological diagnosis was a 10-mm IPT of the liver. After 1.5 years, magnetic resonance imaging revealed two new enhanced lesions in segment 8, which showed the typical pattern of HCC. Because these lesions grew in size for 3 months, liver segmentectomy 8 was performed for HCC recurrence. Histopathological examination showed that both lesions were HCCs.

Conclusion

HCV-related HCC has a high rate of multicentric recurrence. Our experience suggests that, when a hepatic lesion is suspected to be HCC, surgical resection should be considered for curative treatment and to rule out malignancy, even if the lesion may be an IPT.

Shedding light on inflammatory pseudotumor in children: spotlight on inflammatory myofibroblastic tumor

Inflammatory pseudotumor is a generic term used to designate a heterogeneous group of inflammatory mass-forming lesions histologically characterized by myofibroblastic proliferation with chronic inflammatory infiltrate. Inflammatory pseudotumor is multifactorial in etiology and generally benign, but it is often mistaken for malignancy given its aggressive appearance. It can occur throughout the body and is seen in all age groups. Inflammatory pseudotumor has been described in the literature by many organ-specific names, resulting in confusion. Recently within this generic category of inflammatory pseudotumor, inflammatory myofibroblastic tumor has emerged as a distinct entity and is now recognized as a fibroblastic/myofibroblastic neoplasm with intermediate biological potential and occurring mostly in children. We present interesting pediatric cases of inflammatory myofibroblastic tumors given this entity's tendency to occur in children. Familiarity and knowledge of the imaging features of inflammatory pseudotumor can help in making an accurate diagnosis, thereby avoiding unnecessary radical surgery.

[Inflammatory pseudotumour of the liver. Importance of intra-operative histopathology]

BACKGROUND

Inflammatory pseudotumour is a rare entity, considered benign, and characterised by inflammatory cell mesenchymal proliferation.

CLINICAL CASE

The case is presented 70 year-old man with fever of unknown origin syndrome. He was diagnosed with liver abscesses (one segment IV, adjacent to gallbladder fundus and segment VI), who progressed slowly after antibiotic treatment. In the absence of a diagnosis, although fine needle puncture-aspiration and different imaging tests were performed, elective surgery was decided. The intra-operative histopathology reported the existence of an inflammatory pseudotumour.

CONCLUSIONS

Inflammatory pseudotumours are clinically classified into different types according to their aetiology, varying therapeutic management based on the same. It is very difficult to diagnose because of the absence of symptoms, blood disorders, or specific radiological findings. Definitive diagnosis often requires histopathological confirmation, in most cases by percutaneous liver puncture, but sometimes exploratory laparotomy or even performing a hepatectomy for confirmation is necessary. The natural history of inflammatory pseudotumour is its regression; thus conservative management may be used through regular checks until resolution, or can be treated with antibiotics, anti-inflammatories and even corticosteroids. Surgical resection is indicated for persistent unresolved systemic symptoms despite medical treatment, in those situations where growth is evident, with or without symptoms, when involving the hepatic hilum, and finally, in case where the possibility of malignancy cannot be ruled out.

Uncommon hepatic tumors: iconographic essay - Part 2

In cases where typical aspects are shown, the diagnosis of most frequent hepatic lesions can be made with some safety by means of several imaging methods; on the other hand, uncommon lesions generally represent a diagnostic challenge for the radiologist. In the present second part of the study, the authors describe four rare hepatic lesions, as follows: primary hepatic lymphoma, myofibroblastic tumor, primary hepatic neuroendocrine tumor and desmoplastic small round cell tumor, approaching their main characteristics and imaging findings with emphasis on computed tomography and magnetic resonance imaging.

Inflammatory pseudotumor of the colon causing intussusception: A case report and literature review

Inflammatory pseudotumor (IPT) is a rare space-occupying lesion of unknown etiology that can mimic malignancy on clinic-radiological and pathological examination. We describe a rare case of ileocecal intussusception from clinically suspected malignancy of the right colon where the patient underwent right hemicolectomy. Histopathology of the resected specimen confirmed IPT of the colon. This patient was observed to have abnormally elevated total leukocyte count and platelets before and after surgery. In an adult with intussusception associated with an abdominal mass, the possibility of IPT of the colon should be considered. Considering the abnormally high total leukocyte and platelet counts and colonic IPT, it is necessary to prevent postoperative adverse effects due to these changes. Although IPT of the colon is usually a benign process, controversy regarding its management still exists. We consider hemicolectomy as a safe treatment approach for colonic IPT and review the existing literature.

Hepatic inflammatory pseudotumor associated with xanthogranulomatous cholangitis mimicking cholangiocarcinoma

Inflammatory pseudotumor (IPT) is a rare benign condition often misdiagnosed as malignancy. An 80-year-old man was referred to our clinic for an asymptomatic hepatic mass detected on plain abdominal CT. Abdominal ultrasonography identified the lesion as a poorly defined hypoechoic mass. Although a liver biopsy did not provide any evidence of malignancy, imaging modalities suggested a diagnosis of cholangiocarcinoma. The patient underwent left lobectomy, and the pathological findings were consistent with the features of xanthogranulomatous cholangitis. This case is the first report of hepatic IPT originating from xanthogranulomatous cholangitis without symptoms and illustrates the importance of obtaining a preoperative diagnosis in order to avoid a misdiagnosis of malignant tumor.

Inflammatory myofibroblastic tumor of the liver mimicking an infiltrative malignancy in computed tomography and magnetic resonance imaging with Gd-EOB

Inflammatory myofibroblastic tumors (IMT) are a benign tumor entity, which rarely develop in the liver. Surgery is the most common treatment for these lesions as it is difficult to distinguish them from malignant liver tumors and local recurrent growth may occur. IMT is a diagnostic challenge for imaging. Only a limited number of reports of single cases or small number of patients described the imaging features on computed tomography. Reports on IMT appearance on magnetic resonance imaging are scarce. We present a case of IMT of the liver with infiltration of the abdominal wall treated with surgery and describe the imaging features with the use of the hepatobiliary contrast agent, gadoxetic acid (Gd-EOB).

Spectrum of multilocular cystic hepatic lesions: CT and MR imaging findings with pathologic correlation

A multilocular cystic hepatic lesion detected at computed tomography (CT) and magnetic resonance (MR) imaging is a common but nonspecific radiologic finding that can cause potential challenges for differential diagnosis. This imaging pattern may be observed in a wide spectrum of common and uncommon neoplastic or nonneoplastic entities. Neoplastic lesions include cystadenoma, cystadenocarcinoma, hepatocellular carcinoma (HCC), metastases, mesenchymal hamartoma, and inflammatory myofibroblastic tumor. Nonneoplastic lesions include hepatic abscess, echinococcal cyst, intrahepatic hematoma, and biloma. The multiple coalescent cysts seen in polycystic liver disease may exhibit an imaging pattern similar to that of a multilocular cystic lesion. Mural nodularity, irregular thickness of the septa, ragged inner surface, and typical enhancement pattern in the solid portion of the lesion are often indicative of malignancy, although multilocular primary or secondary malignant tumors are uncommon. Recognition of the more common necrosis or cystic change of HCC and metastases induced by locoregional or systemic treatment also is important. The nonenhanced cystic component may be composed of different types of fluids (eg, serous, mucinous, proteinaceous, hemorrhagic, bilious, or mixed) or spontaneous or treatment-related necrosis, whereas the septa may be formed by a wide range of tissues depending on the lesion type. An understanding of the CT and MR imaging findings of these lesions and their respective pathologic correlation aids in accurate diagnosis.

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.

Two rare manifestations of Q fever: splenic and hepatic abscesses and cerebral venous thrombosis, with literature review ma non troppo

Q fever is a zoonosis caused by Coxiella burnetii. It often manifests as a flu-like syndrome; other common manifestations are pneumonia, hepatitis and endocarditis. Its course may be acute or chronic. The authors present two clinical cases of Q fever with rare manifestations. Case 1: A 55-year-old man admitted due to abdominal pain, diarrhoea and fever. Blood tests showed elevated transaminases, low platelets and elevated C reactive protein, with normal white cell counts; abdominal ultrasound showed splenic and hepatic abscesses. Serologies to C burnetii were positive (1:640), leading to the diagnosis of Q fever with splenic and hepatic abscesses. Case 2: A 47-year-old man admitted due to headache after sneezing, with unstable gait and vertigo. A brain tomography showed cerebral venous thrombosis. After an exhaustive investigation, antibodies to C burnetii were found and were undoubtedly positive (1:5120), leading to the diagnosis of Q fever. Both patients were treated with oral doxycycline.

Clinical features, image findings, and prognosis of inflammatory pseudotumor of the liver: a multicenter experience of 45 cases

Background/Aims

Inflammatory pseudotumor (IPT) of the liver is a rare disease characterized by chronic infiltration of inflammatory cells. However, the clinical characteristics and outcomes of IPT remain uncertain.

Methods

Clinical features, image findings, and outcomes of 55 patients with histologically proven IPT were evaluated.

Results

They consisted of 26 men and 19 women with median age of 65 years. Serum carcinoembryonal antigen and carbohydrate antigen 19-9 levels were normal in 42 patients (93.3%). Enhanced CT scans indicated poorly defined peripheral enhancement (82.5%) at the arterial phase and poorly defined hyperattenuating lesions with internal hypoattenuating areas at the equilibrium phase (77.0%). Gadolinium-enhancement MRI revealed poorly defined peripheral rim-like enhancement (77.8%). Ten patients underwent surgical resection and 35 were treated conservatively with or without antibiotics. No recurrence was noted after surgical resection during follow-up (1 to 48 months). In all patients who received conservative treatment, complete resolution or size reduction was noted during follow-up (1 to 192 months).

Conclusions

CT and MRI provide clues to the diagnosis of IPT in patients with liver masses and normal tumor markers. However, due to the lack of pathognomonic findings, the clinician's suspicion and histological diagnosis are necessary to make an accurate diagnosis of IPT.

Inflammatory myofibroblastic tumor mimicking hepatocellular carcinoma with dense lipiodol uptake

Inflammatory myofibroblastic tumor (IMT) of the liver is a very rare lesion that has radiologic similarity with malignant liver tumor. Differential diagnosis of IMT from a malignant lesion of the liver is very important because surgical resection is not mandatory for IMT. Lipiodol computed tomography is a very sensitive and specific diagnostic tool for hepatocellular carcinomas (HCC). Herein, we describe a case of IMT that had dense lipiodol uptake in the tumor and mimicked HCC. To our knowledge, previously, only one case of IMT with dense lipiodol retention has been reported.

Inflammatory pseudotumors mimicking intrahepatic cholangiocarcinoma of the liver; IgG4-positivity and its clinical significance

BACKGROUND

Inflammatory pseudotumor (IPT) of the liver is a benign condition with a good prognosis. However, it is difficult to distinguish clinical and radiological findings of IPT from those of malignancies. The aims of this study are to determine the clinical, radiological, and pathological characteristics, particularly relating to the role of the autoimmune mechanism in the development of inflammatory pseudotumours (IPTs) of the liver, and to suggest appropriate diagnostic and therapeutic strategy.

STUDY DESIGN

The clinical, diagnostic, and pathological characteristics including IgG4 immunohistochemical stain and follow-up data of 22 IPT patients were retrospectively analyzed.

RESULTS

The patients were 16 men and 6 women with a mean age of 59 years. Fifteen patients (68.2%) had associated biliary diseases. Of the 16 patients treated conservatively, the masses completely resolved in 10 patients, and reduced in size in 5 patients within the first 6 months. The remaining 6 patients were treated by surgical resection. IgG4 staining of 17 tissue samples from 22 patients were negative, most of the infiltrate being of fibrohistiocytic type, whereas 4 of 5 lymphoplasmacytic cells of dominant tumors show positive staining of IgG4. Although IgG4-related sclerosing cholangitis was mostly of lymphoplasmacytic type, other histological and clinical characteristics were similar in both types of IPTs.

CONCLUSIONS

IPTs of the liver can be diagnosed based on radiological and pathological findings by needle biopsy. Although the lymphoplasmacytic type of IPTs seems to correspond to IgG4-related disease, as assessed by IgG4 immunohistochemical stain, its clinical significance is unknown. Although most IPTs can be resolved with conservative therapy, surgical resection should be considered in cases of uncertain biopsy result, presumed malignant lesion, combination with other pathology, or lack of response to conservative management.

Inflammatory pseudotumor of the liver and spleen diagnosed by percutaneous needle biopsy

An inflammatory pseudotumor (IPT) is a relatively rare lesion characterized by chronic infiltration of inflammatory cells and areas of fibrosis. IPTs are difficult to diagnose because of the absence of specific symptoms or of characteristic hematological or radiological findings. In this study, a case of a woman aged over 70 years was reported, who presented with a general malaise lasting more than two months. A computed tomography scan demonstrated a diffusely spread lesion of the liver with a portal vein occlusion and a splenic lesion surrounded by a soft density layer. Since the percutaneous liver biopsy showed findings that suggested an IPT, although the radiological findings did not exclude the possibility of a malignancy, we performed a percutaneous spleen biopsy to enable a more definitive diagnosis. The microscopic findings from the spleen specimen lead us to a diagnosis of IPT involving the liver and spleen. Subsequent steroid pulse therapy was effective, and rapid resolution of the disease was observed.

Inflammatory pseudotumor of the liver: a case report and review of the literature

Introduction

Inflammatory pseudotumor of the liver represents a fairly uncommon pathology. Although it is a benign tumor, the correct diagnosis can be missed.

Case presentation

We report the case of a 55-year-old Caucasian man, who presented with a one-month history of abdominal pain and weight loss. He was diagnosed with a primary liver tumor by computed tomography and magnetic resonance imaging. Alpha-fetoprotein levels ranged within normal limits. A right posterior sectorectomy was performed. Histopathology revealed an inflammatory pseudotumor of the liver. Our patient remains in good condition one year later.

Conclusion

Although inflammatory pseudotumor of the liver is usually a benign process, controversy regarding its management still exists. With this case report we review the existing literature and consider hepatectomy as a safe treatment approach.

Inflammatory pseudo-tumor of the liver: a rare pathological entity

Inflammatory pseudo-tumor (IPT) of the liver is a rare benign neoplasm and is often mistaken as a malignant entity. Few cases have been reported in the literature and the precise etiology of inflammatory pseudotumor remains unknown. Patients usually present with fever, abdominal pain and jaundice. The proliferation of spindled myofibroblast cells mixed with variable amounts of reactive inflammatory cells is characteristics of IPT. We reviewed the literature regarding possible etiology for IPT with a possible suggested etiology.

MRI findings of uncommon non-hepatocyte origin primary liver tumours with pathological correlation

The objective of this article was to illustrate the MRI findings of uncommon non-hepatocyte origin primary liver tumours, correlate them with the pathological features and discuss differential diagnoses. In conclusion, the MRI findings of uncommon benign and malignant non-hepatocyte-origin primary liver tumours vary. Awareness of characteristic MRI features can aid differential diagnosis and prevent unnecessary surgery.

An inflammatory myofibroblastic tumor of the ampulla of vater successfully managed with endoscopic papillectomy: report of a case

Inflammatory myofibroblastic tumors (IMTs) are solid neoplastic mesenchymal proliferations composed of myofibroblastic spindle cells admixed with inflammatory infiltrates. The documented sites in the gastrointestinal tract include the esophagus, small intestine, colon, appendix, rectum, pancreas, spleen, liver, and Meckel's diverticulum. Biliary IMTs are rare, and IMTs arising from the ampulla of Vater have not been reported previously. Herein we report the case of a 65-year-old woman with an extrahepatic biliary obstruction due to IMT of the ampulla of Vater, and a successful therapeutic approach using endoscopic ultrasonography and endoscopic papillectomy.

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 pseudotumor in the liver associated with intrahepatic bile duct stones mimicking malignancy

We describe a 71-year-old man with an inflammatory tumor arising in segment 5 of the liver. The patient was admitted because of acute pain in the right upper quadrant of the abdomen and fever. Initial laboratory tests revealed the following: serum alkaline phosphatase concentration, 634 IU/L; serum gamma glutamic transpeptidase concentration, 1,378 IU/L; serum C-reactive protein concentration, 0.89 mg/dL; and total bilirubin concentration, 8.9 mg/dL. Abdominal ultrasonography, computed tomography (CT), and magnetic resonance imaging showed a mass, 3 cm in diameter, in segment 5 of the liver. Magnetic resonance cholangiopancreatography showed a lesion of moderate-to-high signal intensity on T2-weighted images of segment 5. Endoscopic retrograde cholangiopancreatography revealed a common bile duct stone. The intrahepatic bile ducts of segment 5 could not be visualized after the use of contrast material. Endoscopic sphincterotomy was performed to remove the common bile duct stone. Antibiotics were administered soon after stone removal, and fever gradually resolved. Positron emission tomography revealed hot spots in segment 5 of the liver. Three weeks after discharge, the patient was readmitted with an acute pain in the right upper quadrant of the abdomen. Abdominal ultrasonography, CT, and magnetic resonance imaging showed enlargement of this area. Inflammatory changes of segment 5 due to cholangitis with intrahepatic bile duct stones was diagnosed. Because malignant disease could not be completely ruled out, segment 5 of the liver was resected. Macroscopic examination of the resected specimen revealed a gray, fibrotic, solid tumor associated with intrahepatic bile duct stones. Microscopic examination of the tumor showed proliferation of spindle-shaped myofibroblastic cells in a mixed myxoedematous, dense fibrotic stroma, associated with infiltration by various acute and chronic inflammatory cells. The postoperative course was uneventful, and the patient was discharged on postoperative day 16.

Inflammatory pseudotumours of the liver: a spectrum of presentation and management options. Eur J Surg Oncol. 2009;35:1295-1298. [PMID: 19515527 DOI: 10.1016/j.ejso.2009.04.003]

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.

Benign hepatic tumors and iatrogenic pseudotumors

Myriad benign tumors may be found in the liver; they can be classified according to their cell of origin into tumors of hepatocellular, cholangiocellular, or mesenchymal origin. Common benign hepatic tumors may pose a diagnostic dilemma when they manifest with atypical imaging features. Less frequently encountered benign hepatic tumors such as inflammatory pseudotumor or biliary cystadenoma demonstrate less specific imaging features; however, awareness of their findings is useful in narrowing differential diagnostic considerations. In addition, certain iatrogenically induced abnormalities of the liver may be confused with more ominous findings such as infection or neoplasia. However, knowledge of their common imaging appearances, in addition to the clinical history, is critical in correctly diagnosing and characterizing iatrogenic abnormalities of the liver. Familiarity with both expected and unexpected imaging appearances of common benign hepatic tumors, less commonly encountered benign hepatic tumors, and iatrogenic abnormalities potentially masquerading as hepatic tumors allows the radiologist to achieve an informed differential diagnosis.

Real-time contrast-enhanced ultrasound imaging of infected focal liver lesions

OBJECTIVE

The purpose of this study was to investigate the features of infected focal liver lesions on contrast-enhanced ultrasound (CEUS) imaging.

METHODS

Thirty-two hepatic abscesses, 15 infected granulomas, and 6 inflammatory pseudotumors in 53 patients were evaluated with real-time CEUS before awareness of the definitive diagnosis. A 2.4-mL dose of a sulfur hexafluoride-filled microbubble contrast agent was administered by intravenous bolus injection.

RESULTS

The numbers of abscesses with hyperenhancement, isoenhancement, and hypoenhancement in the arterial phase were 26 (81.3%), 5 (15.6%), and 1 (3.1%), respectively. Thirty (93.8%) lesions were irregularly rim enhanced with nonenhanced areas; enhanced septa were shown in 22 (68.8%) lesions; and transient hyperenhancement of liver parenchyma around the lesion was shown in 20 (62.5%). In 31 abscesses with hyperenhancement or isoenhancement in the arterial phase, 25 (80.6%) showed contrast wash-out and changed in appearance to hypoenhancement in the late phase. As for infected granulomas and inflammatory pseudotumors, 16 (76.2%) lesions showed hyperenhancement or isoenhancement in the arterial phase, and all of them were hypoenhanced in the portal and late phases.

CONCLUSIONS

Most infected focal liver lesions showed more rapid contrast wash-out than the surrounding liver parenchyma, which is similar to malignant lesions. Abscesses typically showed features of rim enhancement, enhanced internal septa, nonenhanced central necrotic areas, and transient hyperenhanced liver parenchyma around the lesions. The CEUS appearance of infected granulomas and inflammatory pseudotumors was variable, and a biopsy was necessary for definitive diagnosis.

Inflammatory pseudotumor of the liver: report of eight cases, including three unusual cases, and a literature review

BACKGROUND

Inflammatory pseudotumor (IPT) of the liver is a rare but increasingly recognized tumor-like lesion. This condition is becoming an important differential diagnosis in patients with hepatic space-occupying lesions. This study reports the clinical features of eight cases of IPT of the liver, including the first report of three cases with an unusual associated disease or clinical course.

METHODS

The study sample included cases of IPT diagnosed based on the histopathology in our institution from 1995 to 2004. Clinical events were reported and compared with reports in the literature.

RESULTS

The age of the patients ranged from 28 to 78 years. The most common symptoms were abdominal pain, fever and bodyweight loss. Three patients were diagnosed incidentally. The initial clinical diagnoses were hepatocellular carcinoma in three cases, liver abscess in two cases, metastasis in one case and uncertain nature in two cases. Two cases were associated with preceding endophthalmitis and cholangiocarcinoma, respectively. Two patients had spontaneous lesion regression, but one of these had possible recurrence 10 months later. The other two patients experienced resolution of their lesions following antibiotic treatment. Four patients underwent surgical resection with subsequent recovery.

CONCLUSIONS

The clinical and imaging features of IPT in this small series were found to sometimes mimic those of malignant liver tumors or abscess. Surgical resection was performed in half of the cases. However, IPT of the liver could resolve spontaneously or following antibiotics treatment.

Inflammatory pseudotumor of the liver successfully treated with nonsteroidal anti-inflammatory drugs: a challenge diagnosis for one not so rare entity

Inflammatory pseudotumor of the liver is a rare, benign lesion characterized by a well-circumscribed mass of chronic inflammatory cell infiltration and proliferating fibrous tissue. Its etiology remains unclear, although inflammatory processes have been proposed. It is often misdiagnosed as a malignant tumor, and the management has been traditionally surgical. We report the case of a 16-year-old boy who was referred from another hospital with a fever of >38 degrees C with rigor and right upper quadrant pain which he had suffered from for 5 days. The ultrasonographic computed tomography and MRI findings were not diagnostic, and we performed a needle biopsy from the lesion that was consistent with inflammatory pseudotumor (of liver, mixed fibrous tissue and chronic inflammatory cell infiltration). The patient was treated with nonsteroidal anti-inflammatory drugs and had an uneventful clinical course. During follow-up, the lesion subsequently shrank to completely vanish 1 year later.

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.

A hypervascular pseudotumor in the liver with angiodysplasia in the center of the lesion: a new entity or a variant of focal nodular hyperplasia?

A unique case of hypervascular pseudotumor in the liver consisting of central angiodysplasia surrounded by atrophic liver tissue is described. A 45-year-old woman was referred for the incidentally found hepatic lesion. Computed tomography with contrast showed strong enhancement of the lesion in the arterial phase, and the effect persisted to the parenchymal phase. Doppler ultrasonography showed winding dilated blood flows into the lesion. Because the pathological examination of the biopsy specimen showed the possibility of a well-differentiated hepatocellular carcinoma, she underwent surgery. Final pathological findings showed that the lesion demonstrated atrophic change of the liver tissue with a cluster of abnormal vessels of various sizes in the center. Although there was no primary liver disease, multiple liver metastases from laryngeal carcinoma were found coincidentally. The present lesion could represent a new entity or a variant (or an unknown stage of development) of focal nodular hyperplasia.

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.

Biliary Inflammatory Pseudotumor: Imaging Features in Seven Patients

OBJECTIVE

Hepatic biliary pseudotumor is a benign, rare, and poorly understood tumor that is typically diagnosed after aggressive surgical intervention. The purpose of this report is to describe the clinical and imaging features of this tumor in seven patients.

CONCLUSION

Although secondary clinical features may rarely suggest inflammatory pseudotumor, the typical presenting symptom--painless obstructive jaundice--is indicative of malignancy. The imaging appearance of hepatic hilar biliary pseudotumor is also indistinguishable from that of cholangiocarcinoma.

Unusual mesenchymal liver tumors in adults: radiologic-pathologic correlation

OBJECTIVE

Our purpose was to review a broad spectrum of mesenchymal liver tumors in adults and present their cross-sectional imaging characteristics including radiologic-pathologic correlation.

CONCLUSION

Cross-sectional imaging findings of mesenchymal liver tumors in adults are varied and some may overlap with others or even with more common malignant epithelial tumors. However, in some cases, their appearances at cross-sectional imaging studies may reflect characteristic abnormalities that suggest a specific diagnosis. Therefore, familiarity with the radiologic findings of mesenchymal liver tumors and understanding their pathological background is important for increasing the accuracy of radiologic diagnosis.

A case of hepatic inflammatory pseudotumor identified by FDG-PET

A 53-year-old man with a history of nausea and elevated liver functions presented to our clinic. A CT scan showed a small tumor in the right lobe of the liver. Fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography confirm abnormal metabolic activity with a high standardized uptake value of 7.3 in the lesion. These findings could indicate a malignancy such as well-differentiated hepatocellular carcinoma or cholangiocarcinoma, or a benign lesion such as hepatic abscess. He was diagnosed by histopathological examination as having an epithelioid granuloma with many inflammatory cells. This is the rare report of hepatic inflammatory pseudotumor featuring markedly increased 18F-FDG uptake.

Solid Organizing Hepatic Abscesses Mimic Hepatic Tumor

OBJECTIVE

To describe the computed tomography (CT) and magnetic resonance imaging (MRI) findings of solid organizing hepatic abscesses and correlate them with the pathologic findings.

METHODS

Ten patients with 10 pathologically proven solid organizing hepatic abscesses who underwent 3-phase CT (n = 10) or MRI (n = 7) were enrolled in this study. Images were retrospectively analyzed by consensus of 2 radiologists for attenuation (signal intensity), shape, and margin of the lesions as well as for their enhancement patterns. Their imaging findings were correlated with their pathologic findings.

RESULTS

The main imaging finding on CT or MRI was the well-defined target appearance of a central enhancing area with a low-attenuation (signal intensity) rim on arterial and portal phases. On the delayed phase, most of lesions showed slightly low attenuation (signal intensity) with an enhancing rim, and 1 showed diffuse enhancement. Pathologically, the central areas and peripheral rims corresponded to granulation tissue and fibrosis, respectively. Nine lesions demonstrated a tiny necrotic cystic portion in the center.

CONCLUSION

The target appearance of solid organizing hepatic abscesses on CT and MRI can be helpful in differentiating them from other focal liver lesions. These imaging findings are well correlated with the pathologic findings.

Inflammatory pseudotumor in the Spiegel lobe of the liver of an elderly woman

We describe an inflammatory tumor in the Spiegel lobe of the liver of an 81-year-old woman. The patient was referred to our hospital for evaluation of a fever of over 39 degrees C and upper abdominal pain. Both conditions had persisted for five days in spite of antibiotic treatment. Initial laboratory tests revealed a serum C-reactive protein concentration of 20.9 mg/dL and white blood cell count of 15,500/microL. Abdominal ultrasound showed a hypoechoic lesion measuring 4 cm in diameter in the Spiegel lobe of the liver. A follow-up abdominal ultrasound revealed that the hypoechoic lesion was not decreased in size. Computed tomography showed a moderate-to-high-density area in the arterial phase and a low-density area in the Spiegel lobe on delayed phase. Magnetic resonance imaging showed a faint low-intensity lesion on T1-weighted imaging and moderate-to-high-intensity lesion on T2-weighted imaging in the Spiegel lobe. Angiography showed a slight hypervascularity in the area of the Spiegel lobe. Antibiotics and nu-globulin were commenced soon after admission and the fever gradually improved. Ultrasound-guided liver biopsy revealed that the hepatic parenchyma was almost completely replaced by dense hyalinized fibrous tissue and inflammatory cells. These findings were construed to indicate a benign lesion, but the tumor remained unchanged. Malignant disease could not be completely ruled out. Segment 1 of the liver was resected. Macroscopic examination of the resected specimen revealed a gray, fibrotic, solid tumor. The border of the tumor was well-circumscribed but not encapsulated. Microscopically, the tumor showed a marked fibrotic background with infiltration by a mixed population of lymphocytes, plasma cells, histiocytes, and reactive, plump spindle cells. The postoperative course was uneventful. The patient has remained well in the 10 months since the resection without recurrence.

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 pseudotumor of the liver: ferumoxide-enhanced MR imaging as a tiebreaker

We examined a 70-year-old male patient with an inflammatory pseudotumor of the liver mimicking a peripheral-type cholangiocellular carcinoma. Ferumoxide-enhanced magnetic resonance (MR) imaging revealed residual Kupffer cell function in liver parenchyma in and surrounding the inflammatory pseudotumor involvement, which suggested the diagnosis of inflammatory pseudotumor of the liver. We correlate the MR imaging and pathologic findings in this report.