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

Hepatic Inflammatory Pseudotumor-Focusing on Its Heterogeneity

Hepatic inflammatory pseudotumors (IPTs) are defined as benign, non-malignant, non-metastasizing tumors characterized by the presence of myofibroblastic spindle cells, hetorogenous populations of inflammatory cells, particularly plasma cells, lymphocytes and macrophages, as well as locations of fibrosis and necrosis without cellular anaplasia or atypical mitoses. Despite subsequent reports in the references, hepatic IPT remains difficult to diagnose; while posing major issues specifically for its differential diagnosis compared with that of other various benign diseases and malignant hepatic tumors. Histopathological findings are always a requisite for confirming the diagnosis, particularly given that the pathogenesis of IPT remains ambiguous to date. Hepatic IPT is a heterogeneous entity in terms of its clinical features, pathological findings, and pathogenesis. Once the diagnosis is confirmed, however, needless surgery such as wedge resection and lobectomy should be avoided. Here, we discuss the heterogeneity of hepatic IPT, its clinical features, pathological findings, and pathogenesis, and describe its differential diagnosis.

A Case of Inflammatory Pseudotumour Masquerading as Hepatocellular Carcinoma

Inflammatory pseudotumors (IPTs) of the liver can mimic malignant lesions. As the name implies, they are usually associated with an inflammatory process and usually regress with the treatment of the underlying pathology. We report a case of a 67-year-old female who presented with right upper quadrant pain, deranged liver enzymes, elevated tumor markers [alpha-fetoprotein (AFP) and CA 19-9], and a large liver mass on imaging, suspected to be hepatocellular carcinoma (HCC). She was eventually diagnosed with IPT complicating the liver inflammation due to autoimmune hepatitis (AIH). She responded well to treatment with steroids and immunosuppressive therapy.

Laparoscopic treatment of inflammatory myofibroblastic tumor in liver: A case report

BACKGROUND

Inflammatory myofibroblastic tumor in the liver (IMTL) is a rare borderline mesenchymal tumor. Neither clinical symptoms nor laboratory tests have absolute specificity for the diagnosis of IMTL, and imaging also lacks obvious specificity. Although there are sporadic reports of recurrence after surgical treatment, surgical resection is the mainstay of treatment.

CASE SUMMARY

A 29-year-old man complained of general weakness, slight discomfort in the upper abdomen, with a history of upper respiratory tract infection for 1 wk before admission. Plain and enhanced upper abdominal magnetic resonance imaging showed a mass in liver segments II and III (48 mm × 53 mm). He was treated by laparoscopic left lateral segmentectomy. Postoperative pathological examination with hematoxylin and eosin staining suggested that the mass in liver segments II and III was IMTL. During 21 mo postoperative follow-up, no obvious residual or recurrent lesions were observed.

CONCLUSION

There is a risk of malignant degeneration in IMTL. The principal choice of treatment is laparoscopic left lateral segmentectomy.

[Inflammatory Myofibroblastic Tumor Misdiagnosed as Intrahepatic Cholangiocarcinoma]

An inflammatory myofibroblastic tumor (IMT) is a rare tumor that is currently classified as an intermediate cancer according to the World Health Organization classification system. The pathophysiology of its occurrence is still unknown. Imaging tests, such as CT or MRI, can be helpful in diagnosis, but the final diagnosis is confirmed by a pathological examination through a biopsy and immunohistochemistry stain. The patient, in this case, presented an asymptomatic intrahepatic mass discovered incidentally on an imaging examination. Initially, intrahepatic cholangiocarcinoma was suspected, but she was finally diagnosed with IMT through a histological examination after a liver resection.

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.

Fibrohistiocytic Variant of Hepatic Pseudotumor: An Antibiotic Responsive Tumefactive Lesion

Inflammatory pseudotumor is a term used to designate inflammation-rich tumefactive lesions. Following the exclusion of specific entities such as IgG4-related disease and other neoplastic entities previously included in this entity, the majority of hepatic pseudotumors show a prominent fibrohistiocytic inflammatory reaction and have been previously categorized as fibrohistiocytic variant of hepatic pseudotumor (FHVHPT). The goal of this study was to examine the clinical, radiologic, histologic, and etiologic aspects of this entity. After excluding neoplastic diseases, we identified 30 patients with FHVHPT from 3 institutions between 2009 and 2019. We extracted demographic and clinical data, liver function tests as well as culture results and radiologic information. Hematoxylin and eosin-stained slides were reviewed for pattern of inflammation as well as its cellular composition. Immunohistochemistry for IgG4 and IgG was performed in all cases. The mean age of the 30 lesions characterized as FHVHPT was 56 years (range: 23 to 79 y). Nineteen patients showed solitary lesions; 11 were multiple. The mean size of the lesion was 3.8 cm (range: 1 to 7.5 cm). On imaging, a neoplastic process or metastasis was the leading diagnostic consideration (n=15, 50%). The most common symptom was abdominal pain (n=14/30); 8 patients presented with symptoms compatible with an infectious process, including fever. The inflammatory infiltrate was dominated by lymphocytes and plasma cells, and in most cases, a prominent histiocytic infiltrate (22/30). Neutrophils were identified in 12 cases, with microabscess noted in 8. Storiform pattern of fibrosis was seen in 14/30 cases; obliterative phlebitis was not identified. Culture identified a microorganism in 4 of 9 cases evaluated. The mean IgG4 count was 9.3 per HPF (range: 0 to 51) with 9 of the 26 (35%) biopsies showing >10 IgG4 positive plasma cells per HPF. The mean IgG4 to IgG ratio was 8% (range: 8% to 46%). A hepatectomy was performed in 4 cases. On broad spectrum antibiotics (n=14) the lesions either resolved or decreased in size. Eight patients did not receive specific therapy, nevertheless, the lesion(s) resolved spontaneously in 6 cases, remained stable or decreased in size in 2 cases. Notably, none of these patients showed evidence of a hepatic recurrence. FHVHPT, a tumefactive lesion that mimics hepatic neoplasia, is histologically characterized by a fibrohistiocytic infiltrate. In the majority of patients FHVHPT represents the organizing phase of hepatic abscess and can be successfully managed with antibiotic therapy.

Inflammatory myofibroblastic tumors arising from pancreas head and peri-splenic area mimicking a malignancy

Inflammatory myofibroblastic tumors (IMTs) are a rare chronic inflammatory disease with unclear pathogenesis and pathological features that are not those of a malignant tumor. It is difficult to differentially diagnose them without surgical excision because of their unpredictable clinical behavior, which ranges from benign to locally invasive aggressiveness. We report two cases of IMTs that were diagnosed after surgery. In one case, the IMT originated in peri-splenic area in a 63-year-old female patient. The other case involved a 48-year-old female patient who suffered from an IMT of the head of the pancreas. Both of these cases did not require further treatment based on histological findings, and there has been no evidence of recurrence or metastasis so far. These cases show that the primary choice for the exact diagnosis and proper treatment of IMTs is complete surgical resection.

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.

Intratumor Abscess in a Posttraumatic Hepatic Inflammatory Pseudotumor Spreading Out of the Liver

A 45-year-old woman with abdominal pain after minor trauma was referred to our hospital. Computed tomography (CT) showed a hypovascular tumor in the left liver lobe. A tumor biopsy revealed granuloma, although no findings indicated malignancy or infection. A follow-up imaging study showed spread of the hepatic tumor. Her abdominal pain worsened after a second minor trauma. CT revealed an intratumor abscess, and pus overflowed from the patient's umbilicus. The abscess was improved by antibiotics and drainage therapy. In this case, unusual imaging findings and an atypical disease course of a hepatic inflammatory pseudotumor were observed.

Inflammatory myofibroblastic tumor of the liver: A case report and review of literature

BACKGROUND

Inflammatory myofibroblastic tumors of the liver (IMTL) are extremely rare neoplasms and very little is known about their clinical presentation, pathogenesis, and biological behavior. Due to their absolute rarity, it is almost impossible to obtain a definite diagnosis without histological examination. Because of their intermediate biological behavior with the risk for local recurrence and metastases, surgical resection is recommend whenever IMTL is suspect.

CASE SUMMARY

We herein present a case of an otherwise healthy 32-year-old woman who presented with intermittent fever, unclear anemia, malaise and right flank pain 4 mo postpartum. The liver mass in segment IVa/b was highly FDG avid in the positron emission tomography-computed tomography. Hepatic resection was performed achieving a negative resection margin and an immediate resolution of all clinical symptoms. Histological analysis diagnosed the rare finding of an inflammatory myofibroblastic tumor of the liver and revealed cytoplasmic anaplastic lymphoma kinase expression by immunohistochemistry. Twelve months follow-up magnetic resonance imaging showed no recurrence and no metastases in the fully recovered patient.

CONCLUSION

IMTLs are extremely rare and difficult to diagnose. Due to their intermediate biological behavior, surgical resection should be perform whenever feasible and patients should be followed-up in order to detect recurrence and metastasis as early as possible.

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.

Spontaneous Resolution of IgG4-Related Hepatic Inflammatory Pseudotumor Mimicking Malignancy

Hepatic inflammatory pseudotumor (IPT) is characterized by a well-circumscribed benign tumor mimicking or often mistaken for a malignant lesion. A 48-year-old male presented to the hospital with complaints of epigastric pain, with initial laboratory findings showing mildly elevated alkaline phosphatase (140 U/L) with normal AST, ALT, bilirubin, and lipase, a CD4 count of 384, and an HIV viral load of > 10 million copies. The total IgG level was elevated to 2,228 mg/dL (normal IgG4 level 114 mg/dL). Contrast-enhanced MRI of the abdomen showed heterogeneous mass-like infiltration in the right lobe of the liver measuring 9.6 cm. The liver mass was biopsied which showed dense collagenous fibrosis with abundant lymphoplasmacytic infiltrates with 18 IgG4-positive plasma cells per high-power field. The patient was not given any treatment for this IPT. For more than 1 year of follow-up triple-phase CT scan of the liver was repeated, which showed no liver mass. As radiological images of hepatic IPTs, including IgG4-related hepatic IPT, mimic liver malignancy, histological analysis of the biopsy remains the cornerstone for the diagnosis. Symptomatic patients with IgG4-related hepatic IPT have shown improvement with corticosteroid use; however, spontaneous resolution has also been reported like in the present case.

Imaging features of rare mesenychmal liver tumours: beyond haemangiomas

Tumours arising from mesenchymal tissue components such as vascular, fibrous and adipose tissue can manifest in the liver. Although histopathology is often necessary for definitive diagnosis, many of these lesions exhibit characteristic imaging features. The radiologist plays an important role in suggesting the diagnosis, which can direct appropriate immunohistochemical staining at histology. The aim of this review is to present clinical and imaging findings of a spectrum of mesenchymal liver tumours such as haemangioma, epithelioid haemangioendothelioma, lipoma, PEComa, angiosarcoma, inflammatory myofibroblastic tumour, solitary fibrous tumour, leiomyoma, leiomyosarcoma, Kaposi sarcoma, mesenchymal hamartoma, undifferentiated embryonal sarcoma, rhabdomyosarcoma and hepatic metastases. Knowledge of the characteristic features of these tumours will aid in guiding the radiologic diagnosis and appropriate patient management.

Combined liver transplant and pancreaticoduodenectomy for inflammatory hilar myofibroblastic tumor: Case report and review of the literature

IMT, previously known as IPT, is a relatively rare tumor that was originally described in the lungs, but case reports have reported the tumor in almost every organ system. Surgical resection is typically the mainstay of therapy; however, tumors have also been shown to respond to chemotherapy or anti-inflammatory therapy and some have spontaneously regressed. We present a literature review and case report representing the first documentation to date of liver transplant combined with PD for surgical resection of a myofibroblastic tumor non-responsive to medical therapy.

Pathologically Proven Spontaneous Remission of IgG4-related Retroperitoneal Fibrosis

Some forms of idiopathic retroperitoneal fibrosis (RF) have recently been considered to be a part of the spectrum of immunoglobulin G4 (IgG4)-related disease. This case report is the first description of a spontaneous remission in a patient with pathologically proven IgG4-related RF. Although the pathogenesis and long-term disease behavior of IgG4-related RF remains unknown, we believe that an initial assessment consisting of only careful monitoring might be one important strategy, especially in asymptomatic IgG4-related RF patients without nephropathy, while carefully monitoring these patients for the risk of recurrence.

A case of hepatic inflammatory pseudotumor protruding from the liver surface

We report a case of a resected hepatic inflammatory pseudotumor (IPT) protruding from the liver surface. A 69-year-old male with diabetes mellitus was admitted to hospital for investigation of an hepatic mass. An irregularly shaped, low-echoic mass measuring 21 × 18 mm was identified by ultrasound in S6. On computed tomography, the tumor appeared to be growing extrahepatically. After contrast enhancement, the lesion showed persistent peripheral enhancement, while the central part was hypoenhanced. On T2-weighted magnetic resonance imaging (MRI), the central portion of the lesion was hyperintense compared with the periphery. EOB-enhanced MRI revealed the mass to be being hypointense in contrast to the surrounding liver parenchyma in the hepatobiliary phase. On diffusion-weighted images, the lesion was hyperintense. Percutaneous biopsy was not attempted to avoid tumor cell dissemination. The patient underwent partial hepatectomy because of suspected malignancy. Histopathological examination of the resected specimen revealed fibrotic tissue and abundant vessels in the periphery, while a massive infiltration of inflammatory cells and fewer vessels were observed in the center. The patient was finally diagnosed with hepatic IPT of the fibrohistiocytic type.

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

Reported here is the case of a 55-year-old man who had tarry stools for 3 days before he was seen at this Department. The man had weight loss and an intermittent fever for 3 months prior. Histopathology revealed an inflammatory pseudotumor of the liver. This case is reported here along with a review of the literature. Nine days after surgery, the patient passed bright red blood (150 mL) in the stool with no clear trigger. A colonoscopy a month later revealed no abnormalities. This is a rare report of an inflammatory pseudotumor featuring intractable bleeding. An inflammatory pseudotumor of the liver is a rare condition, and differentiating this pseudotumor from hepatic space-occupying lesions is crucial. An inflammatory pseudotumor of the liver may spontaneously regress and mimic other liver tumors. The treatment of choice for this pseudotumor is still surgical resection, and this is especially true for patients with severe symptoms or an indeterminate diagnosis.

Inflammatory Myofibroblastic Tumor of Liver Masquerading as Focal Nodular Hyperplasia in a Patient with Non-Cirrhotic Portal Hypertension and Biliary Pancreatitis

Inflammatory myofibroblastic tumor (IMT) is a rare lesion of undetermined pathogenesis characterized by proliferation of spindled myofibroblast cells in a collagenized inflammatory background. It is usually benign but may show local infiltration or, in rare cases, metastasis. IMT has been observed in almost all solid organs; however, involvement of liver is exceptional. Its symptoms and radiological findings can mimic malignancy and pose diagnostic difficulties. The authors report the case of a 43-year-old woman with non-cirrhotic portal hypertension and gall stone induced acute pancreatitis having a mass in the right lobe of the liver which was initially diagnosed as focal nodular hyperplasia on imaging but proved to be inflammatory myofibroblastic tumor on pathological and immunohistochemical examination. The lesion resolved with conservative management without the need for surgical intervention.

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.

Intra-abdominal inflammatory myofibroblastic tumor: Spontaneous regression

Inflammatory myofibroblastic tumors are usually treated by surgical resection. We herein report two cases of intra-abdominal inflammatory myofibroblastic tumors that were unresectable and underwent spontaneous regression without any treatment. Our case report and literature review show that regression is more common in the middle-aged and older male populations. Abdominal discomfort and fever were the most common symptoms, but the majority of patients had no obvious physical signs. There was no specific indicator for diagnosis. The majority of the lesions regressed within 3 mo and nearly all of the masses completely resolved within 1 year. We conclude that the clinical characteristics of inflammatory myofibroblastic tumors are variable and, accordingly, the disease needs to be subdivided and treated on an individual basis. Surgery is always the first-line treatment; however, for those masses assessed as unresectable, conservative therapy with intense follow-up should be considered.

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.

Rare presentation of self-resolving multifocal inflammatory pseudo-tumour of liver

Inflammatory pseudo-tumour (IPT) of the liver is a rare condition with the appearance of a tumour-like space occupying lesion. Aetiology and natural history is not known for these benign lesions, as they are commonly diagnosed as malignant lesions and frequently undergo surgical resection since spontaneous resolution is very rare. Multifocal IPT involving both lobes of liver are rarely reported. Here we report a unique case of multifocal IPT of the liver which resolved spontaneously within 5 wk period.

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 pseudotumours in the abdomen and pelvis: a pictorial essay

Inflammatory pseudotumours are uncommonly encountered lesions in the abdomen and pelvis that often present with variable and nonspecific imaging features. They may mimic other more common lesions, including malignancy. Within the appropriate clinical context, inflammatory pseudotumours merit consideration in the differential diagnosis of soft-tissue masses within the abdomen and pelvis. A preoperative diagnosis of inflammatory pseudotumour, established through biopsy, may help to differentiate this benign entity from malignancy. In this article, we reviewed the imaging features of inflammatory pseudotumours of the abdomen and pelvis, including liver, spleen, bowel, retroperitoneum, kidney, bladder, uterus, and adnexa.

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.

Sonazoid-enhanced ultrasonography and Ga-EOB-DTPA-enhanced MRI of hepatic inflammatory pseudotumor: a case report

A liver neoplasm was found in a 63-year-old man with alcoholic liver disease. Sonazoid-enhanced ultrasonography (US) showed that the neoplasm was isoechoic at the early vascular phase and hypoechoic at the post-vascular phase. Gadolinium ethoxybenzyl-diethylenetriamine-enhanced magnetic resonance imaging (MRI) showed that the neoplasm was hypointense at the hepatobiliary phase. We suspected that it was a malignant tumor. By needle biopsy, however, the neoplasm was diagnosed as an inflammatory pseudotumor (IPT). We encountered a rare case of hepatic IPT, the differential diagnosis of which was difficult to distinguish from malignant tumor. Here, we report new US and MRI findings of hepatic IPT.

A new case of spontaneous regression of inflammatory hepatic pseudotumor

Introduction. Inflammatory pseudo-tumors (IPT) of the liver are rare and difficult to diagnose, because mimicking malignant tumors. Aim. We report a case of IPT of the liver wich diagnosis was made on clinical, radiological and evolutif features. Observation. A 15-year-old man had a 4-month history of abdominal pain in the right upper quadrant with fever and cought. Two successives ultrasonographies revealed a hypoechoic lesion occuping the segment VIII with 8 cm of diametre. Physical examination was normal. Laboratory investigation showed normal blood counts, liver function test and tumoral markers. Another ultrasonography was interpretated as normal. Tomodensitometry had showon a 3-cm lesion wich enhanced later after contrast injection. A second tomodensitometry done one mounth later described a 2-cm sub capsular heaptic lesion. Discussion. On routine activiy, pre operative diagnosis of IPT of the liver is difficut, and rarely made with certitude because mimicking a malignant tumor. In our cae report here, the analysis of previous history, of clinical, biological and radiological presentation, had permittes us to pose the diagnosis of PTI of the liver and this despite the absence of histological confirmation by percutaneous biopsy.

Hepatic and pulmonary nodular lesions in pediatric urinary tract infections

One of the major goals in investigating children with urinary tract infection (UTI) is to recognize patients at risk of further UTI-related problems. This study reports the clinical features of 19 pediatric patients with UTIs in whom associated hepatic and/or pulmonary nodules were incidentally diagnosed by the imaging tests performed for the UTI. Hepatic nodules in five patients were detected on ultrasound scans, and pulmonary nodules and both hepatic and pulmonary nodules were detected in 12 and two children by dimercaptosuccinic acid scintigraphy. The mean age of the patients was 24.5 months. Vesicoureteral reflux (VUR) was detected in nine of 17 patients (52.9%), acute pyelonephritis was identified in nine of 18 patients, and renal scarring was found in 57.1% patients with pyelonephritis. On follow-up, the hepatic and/or pulmonary nodules regressed in all patients. About 85.7% of patients experienced a recurrence of UTI within 1 year. In comparison with age- and sex-matched controls with UTIs without pulmonary or hepatic nodules, the presence of VUR and the recurrence of UTI within 1 year were higher in patients with UTIs and nodules (P<0.05). The hepatic and/or pulmonary nodules identified on the ultrasound scan and by dimercaptosuccinic acid scintigraphy may provide a valuable diagnostic marker for the proper management of patients with an UTI.

Spontaneous regression of an anterior skull base mass

Spontaneous regression of an intracranial mass is rare. We report a 77-year-old man with spontaneous regression of an anterior skull base mass suspected to be an inflammatory pseudotumor. The patient attended our outpatient department approximately once per month for a regular check-up following a brain stem infarction. A small mass was detected at the anterior skull base by MRI. The mass gradually grew to about 3 cm over a period of 5 years and then remained stable for 3 years. Thereafter, the mass showed spontaneous regression 8 years after it was first visible on MRI. 'Inflammatory pseudotumor' is a broad category and the natural history of these lesions is highly variable. Although the definition does include some types of malignant lesion, most masses are benign lesions that can regress spontaneously, as in our patient. A 'wait-and-see' policy is appropriate for such patients.

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.

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.