Inflammatory pseudotumor (myoblastic tumor) of the genitourinary tract. AJR Am J Roentgenol. 2008;191:1255-1262. [PMID: 18806173 DOI: 10.2214/ajr.07.3663]

Laparoscopic Management of an Inflammatory Pseudotumor Mimicking a Locally Advanced Renal Carcinoma: A Diagnostic Pitfall

Inflammatory pseudotumors of the kidney are an infrequent entity. More frequently described in the lung, the genitourinary tract location is rare. Commonly described in the bladder, the kidney damage remains exceptional. Herein, we report the case of 60 years old man with a history of flank pain, initially diagnosed with a locally advanced left renal carcinoma invading the left colon. Then, after performing a laparoscopic radical nephrectomy, the histopathological diagnosis of inflammatory pseudotumor of the left kidney has been made.

Inflammatory myofibroblastic tumour: case report of a rare form of bladder tumour

Introduction and importance

Inflammatory myofibroblastic tumour (IMT) is a rare tumour with malignant potential and has been described in many major organs with the most frequent site being the lungs. However, bladder is an extremely rare location. IMT presents a unique diagnostic challenge because of the characteristics it shares with malignant neoplasms.

Case presentation

Here we report the case of a 47-yearold male who presented with storage lower urinary tract symptoms associated with non-specific lower abdominal pain for one month duration. Contrast-enhanced computed tomography of abdomen and pelvis revealed a 6 cm tumour at the dome and left side anterior wall of the bladder. He underwent laparotomy and partial cystectomy. Histopathology results were consistent with an IMT.

Clinical discussion

Even though bladder IMT is indolent in course, typical IMTs can be locally aggressive. Due to the lack of specificity in clinical symptoms, it is not easy to arrive at a precise diagnosis before surgery. Hence, the final diagnosis depends on histomorphological features and the immune histochemical profile.

Conclusion

It can be challenging to distinguish IMT from malignant neoplasms both clinically and histologically. As such, local surgical resection with close follow-up remains the mainstay of treatment for urinary tract IMT.

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Occurrence of IMT is rarely encountered in the urinary tract.

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A 47-year old male with urinary bladder tumour was histopathologically revealed to be of IMT type.

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Tumour was at the dome of the bladder and left side anterior bladder wall abutting the sigmoid colon.

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The final diagnosis depends on histomorphological features and the immune histochemical profile.

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Local surgical resection with close follow-up remains the mainstay of treatment for urinary tract IMT.

Unusual cause of urinary retention in a child: inflammatory pseudotumor of the urinary bladder

Background

Urinary bladder masses are uncommon in the pediatric age group and pose a diagnostic challenge, often necessitating histopathological differentiation and confirmation. An unusual mimic of neoplastic bladder mass is inflammatory pseudotumor, and timely identification and diagnosis of which prevents undue patient stress and radical treatment.

Case presentation

We present a case of a 7-year-old female child who presented with hematuria, and a urinary bladder mass was detected on ultrasound which was further characterized by magnetic resonance imaging (MRI) and diagnosed as an inflammatory pseudotumor (IPT) on histopathology.

Conclusions

This case report describes the imaging features of IPT along with a list of differential diagnoses emphasizing the need for radiologists to be aware of this surprising and rare entity.

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 Myofibroblastic Tumor of the Urinary System on Computed Tomography at a High-Volume Institution in China

OBJECTIVE

Inflammatory myofibroblastic tumors (IMTs) of the urinary system are relatively rare and often misdiagnosed. We aimed to summarize and analyze the clinical manifestations, imaging features, management, and follow-up of renal and bladder IMTs.

METHODS

In this retrospective study, 22 patients with IMT pathologically verified between 2009 and 2018 were included. Epidemiologic, clinical, pathologic, and imaging findings were recorded. Tumor size, location, and shape were analyzed and summarized.

RESULTS

There were 22 patients with a median age of 45 years (range: 20-74), including 14 patients with renal IMT and 8 patients with bladder IMT, who met the eligibility criteria. In 21 patients, IMT appeared as a single lesion, whereas 1 patient showed bilateral renal lesions. Surgical resection was the sole therapy, and follow-up information was acquired from 13 individuals with no evidence of recurrence or metastasis. In our study, a slightly hypodense or isodense homogeneous tumor with a clear boundary was more often seen. On contrast-enhanced computed tomography (CT), they were often manifesting as a slightly heterogeneous enhancement.

CONCLUSIONS

The nature of IMTs might cause a lack of generalizability. However, it will be useful to know that there are various CT demonstrations of IMTs. CT images are useful for the detection, location, and characterization of urinary IMTs, which can help in better clinical decision-making and can also be an optimal imaging technique for follow-up.

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.

Pictorial Review of Rare Pancreatic Tumors and Tumor-Like Lesions

췌장에는 다양한 종류의 종양 및 종양 유사 병변들이 생길 수 있다. 이 가운데, 췌장선암은 췌장의 가장 흔한 종양으로서 일반적으로 췌장암이라고 하면 이 종양을 가리킨다. 최근에는 영상 검사의 기술적 진보와 이용이 증가하면서 췌장의 희귀 종양 및 종양 유사 병변들의 발견 빈도가 증가하고 있다. 췌장의 드문 종양 및 종양과 유사한 병변들은 치료 방침과 예후가 췌장선암과 다르기 때문에 이들 질환의 감별은 임상적으로 중요한 의의가 있다. 영상 검사는 포상세포암이나 신경초종 등의 희귀 종양 및 자가면역 췌장염 또는 염증성 거짓종양과 같은 종양 유사 병변들과 췌장선암의 감별 진단에 중요한 역할을 하지만 영상 소견만으로 이들 질환을 정확히 구분하는 것은 한계가 있다. 이 논문에서는 췌장에서 생길 수 있는 희귀 종양 및 종양 유사 병변들의 다양한 영상 소견들과 췌장선암과의 감별에 있어 도움이 되는 특징들을 제시하고자 한다.

Organ-associated pseudosarcomatous myofibroblastic proliferation with ossification in the lower pole of the kidney mimicking renal pelvic carcinoma: A case report

BACKGROUND

Organ-associated pseudosarcomatous myofibroblastic proliferation (PMP) is a very rare disorder. In the urogenital tract, PMP preferentially involves the urinary bladder; kidney involvement is rare. Here, we report a rare case of PMP with ossification in the lower pole of the kidney, which mimics urothelial carcinoma or an osteogenic tumor.

CASE SUMMARY

A Chinese man was admitted to our hospital due to intermittent hematuria for more than 1 mo. Enhanced renal computed tomography revealed a mass in the left renal pelvis and upper ureter. The preoperative clinical diagnosis was renal pelvic carcinoma, determined by imaging examination and biopsy. After a standard preparation for surgery, the patient underwent retroperitoneoscopic radical nephroureterectomy. The operative findings were an extensive renal tumor (6 cm × 4.5 cm × 4.5 cm) invading the lower pole of the kidney and upper ureter. The final pathological diagnosis was organ-associated PMP with ossification. After 6-mo follow-up, no recurrence or metastasis was found.

CONCLUSION

This case of PMP was unusual for its mimicking renal pelvic carcinoma in imaging examinations, making biopsy necessary.

Sonographic Evaluation of Genitourinary Inflammatory Pseudotumors and Its Mimics

Inflammatory pseudotumor is a relatively rare, nonneoplastic lesion composed of inflammatory cells and myofibroblastic spindle cells that can be identified on sonographic evaluation of the genitourinary system. These lesions are thought to be an inflammatory response to insults such as surgery, trauma, infection, or malignancy. Such lesions need to be distinguished from true neoplasms and other benign lesions, including inflammatory responses and infectious processes. Identification of inflammatory pseudotumors and its mimics is important for radiologists to guide patient treatment and follow-up. This pictorial essay presents sonographic features of inflammatory pseudotumors of the genitourinary tract and its mimics with cross-sectional imaging and histopathology, where available.

Female urinary retention from a huge periurethral mass caused by immunoglobulin G4-related disease (IgG4-RD)

Immunoglobulin G4-related disease is a systemic disease, recognized as extensive T-lymphocyte and IgG4-positive plasma cells. It can present as inflammatory pseudotumor in various organs. A female 75 years old, diagnosed IgG4-related autoimmune pancreatitis, presented with urinary retention. Pelvic examination showed well-defined, soft tissue mass, bulging from anterior vaginal wall. MRI pelvis demonstrated a huge periurethral mass, size 6.2 × 4.4 × 4.2 cm, encasing the urethra, extending from bladder neck to distal urethra, and mimicking the prostate gland. Tissue biopsy showed compatible with IgG4-related disease. Immunosuppresive drugs were given for few months and the patient could void normally.

Computed Tomography and Magnetic Resonance Imaging Findings of Inflammatory Pseudotumors in the Abdomen and Pelvis: Current Concepts and Pictorial Review

The group of inflammatory pseudotumors (IPTs) encompasses a variety of rare neoplastic and nonneoplastic entities described to occur in almost every location in the body and whose clinical features and aggressive imaging findings (varying from infiltrative to mass-forming lesions), frequently mimic those of malignant tumors. The radiologic features of IPTs are variable and nonspecific, the imaging findings depending on the body location and involved organ. Abdominopelvic IPTs are rare and the purposes of this review, therefore, are to familiarize the radiologist with the wide spectrum of computed tomography and magnetic resonance imaging findings of IPTs in various locations throughout the abdomen and pelvis, discussing the imaging features that allow consideration of IPTs in the differential diagnosis of soft-tissue masses within the pertinent clinical setting. Radiologists should be aware of this group of entities, as a preoperative histopathologic diagnosis upon radiological suspicion may help to differentiate IPTs from malignancy and to allow the most appropriate clinical work-up for these patients.

Inflammatory myofibroblastic tumor of kidney together with ipsilateral perinephric and periureteric fibrosis: A case report and literature review

RATIONALE

Both inflammatory myofibroblastic tumor (IMT) and retroperitoneal fibrosis are rare lesions, but kidney involvement is more rare. It is the first study about IMT of the kidney in a patient with perinephric and periureteric fibrosis and we hold that fibroblast proliferation may be an intermediate status in oncogenesis of IMT. But further investigation is necessary in order to better clarify the relationship between fibroblast proliferation and IMT.

PATIENT CONCERNS

A 54-year-old female presented no positive signs except dull back pain after overwork.

DIAGNOSES

On the basis of the urinary ultrasonography and computed tomography (CT) scan, we strongly suspected a renal cell carcinoma.

INTERVENTIONS

Considering the little remaining function of the right kidney and the possibility of malignancy, we performed a laparoscopic right radical nephrectomy.

OUTCOMES

According to the analysis of the postoperative paraffin section and immunohistochemistry assay, a final diagnosis of IMT and retroperitoneal fibrosis nodules was made.

LESSONS

Both IMTs are rare lesions and its etiology and pathogeny are unclear. It is the first study about IMT of the kidney in a patient with perinephric and periureteric fibrosis. This report suggested that fibroblast proliferation may be an intermediate status in oncogenesis of IMT, but further investigation is necessary in order to better clarify the relationship between fibroblast proliferation and IMT. The preoperative diagnosis of renal IMT remains difficult. Preoperative fine-needle aspiration or percutaneous biopsy and intraoperative frozen section were applied to confirm the diagnosis to avoid unnecessary nephrectomy, especially in patients with renal insufficiency, bilateral masses, or a solitary kidney.

Imaging findings of inflammatory myofibroblastic tumor from the greater omentum: One case report

RATIONALE

Inflammatory myofibroblastic tumors (IMTs) are rare neoplastic lesions with benign tendency. Even more rare are IMTs from the greater omentum (GO-IMT). A GO-IMT is easily misdiagnosed as other malignant tumors before operation; thus, clinicians need to be familiar with its imaging findings. Here, we report the imaging findings of a GO-IMT patient presenting with a pelvic mass.

PATIENT CONCERNS

Ultrasound of the IMT in the pelvic cavity showed a hypoechoic mass. A computed tomography (CT) scan showed a nearly circular soft tissue mass with a clear border and heterogeneous density, and the surrounding tissues were pushed and compressed. Contrast-enhanced CT showed severe persistent enhancement in the lesion edges and mural nodules, but not in the central necrosis.

DIAGNOSES

Histopathology and immunohistochemistry confirmed that the mass was a GO-IMT.

INTERVENTIONS

The tumor was resected after preoperative preparation.

OUTCOMES

No recurrence or metastasis was found during a short-term follow-up.

LESSONS

The GO-IMT is an inferior epigastric mass in the periphery of the bowel, and is usually well-demarcated without calcification or lymphadenopathy. Contrast-enhanced CT showed a heterogeneous hypervascular mass where the center necrosis, the edge of the tumor, and the mural nodules can be partially reinforced.

Intra-abdominal inflammatory myofibroblastic tumour (IMT) mimicking gonadal mass in a male infant with undescended testes

Inflammatory myofibroblastic tumour (IMT) is a rare benign neoplastic tumour, originally described as an inflammatory pseudotumor. Only a single case of IMT in the spermatic cord associated with undescended testes has been reported. We present a rare case of abdominal IMT in a male infant with undescended bilateral testes. The abdominopelvic mass was suspected to be a gonadal malignancy due to empty scrotal sac but proved to be otherwise on histopathology. Mass was completely resected and orchiopexy was performed for both undescended normal-appearing testes. The patient developed a recurrent mass 2 months later involving the left spermatic cord and the left testicle. Radical surgery was performed with removal of the left testicle and spermatic cord. The patient was disease-free at 1-year follow-up.

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.

A caecal pseoudotumour with an incidental adenomatoid testicular tumour in a man with right undescended testis: a case report

BACKGROUND

Inflammatory pseudotumour refers to a non-malignant tumour-like mass resulting from an inflammatory reaction that is composed of granulation tissue with leukocyte infiltration that commonly occurs in the paediatric or young adult population. These tumours occur more commonly in the lungs and the orbit but rarely does it affect the gastrointestinal tract. It poses a clinical diagnostic challenge since it is a benign condition than can mimic the malignant counterpart. Our case is a rare presentation of the caecal pseudotumour in the presence of a right undescended abdominal testis evaluated as a caecal tumour with a differential diagnosis of a testicular malignancy.

CASE PRESENTATION

We report a 53-year-old male who presented with clinical signs suggestive of right colon tumour and undescended right testis. Intra-operatively, a caecal mass was found with no clearly discernable appendix and extensive adhesion of the right colon to the retroperitoneum, to the liver and gall bladder. A testis was found adherent to the posterior aspect of the caecum and terminal ileum. A right hemicolectomy was performed. Histopathology findings revealed an inflammatory mass with abundant fibroblast proliferation and chronic inflammatory cells infiltrate, involving bowel wall and periceacal adipose tissue; no malignant cells were identified. The testis had within it an adenomatoid tumour nodule. He had uneventful recovery and was discharged home 7 days post-operatively. At the moment, he is symptoms free.

CONCLUSIONS

The occurrence of right colonic inflammatory pseudotumour and co-existent adenomatoid testicular tumour arising from a cryptorchid testis is very unusual. This would make one incline towards a malignant testicular lesion in the presence of cryptorchidism. Testicular adenomatoid tumour is a rare benign neoplasm, mostly affecting fully descended testis and usually does not warrant orchidectomy for purposes of preserving testicular function. On the other hand, surgical resection remains the only safe and curative treatment option available for inflammatory pseudotumours.

CT Manifestations of Inflammatory Myofibroblastic Tumors (Inflammatory Pseudotumors) of the Urinary System

OBJECTIVE

The purpose of this study is to characterize the CT manifestations of inflammatory myofibroblastic tumors (IMTs) of the urinary system in eight patients.

MATERIALS AND METHODS

The CT images of eight pathologically confirmed IMTs were retrospectively reviewed. Two of the eight IMTs occurred in the kidney, and six occurred in the bladder. Seven patients underwent both unenhanced CT and contrast-enhanced CT, and one of the patients who had a bladder tumor underwent unenhanced CT only. The site, shape, size, boundary, internal structure, and enhancement pattern of the lesions were assessed.

RESULTS

The eight patients (five men and three women) whose CT images were reviewed were 18-77 years old (mean age, 53 years). Only one lesion was seen in each of the eight patients. The IMTs occurred at the renal parenchyma (n = 1), the renal pelvis (n = 1), or the bladder (n = 6). Their shape was either roundlike (n = 7) or round (n = 1), and their size ranged from 1.5 × 2.0 cm(2) to 3.7 × 5.2 cm(2). Tumor margins were smooth (n = 5) or lobulated (n = 3), and boundaries were clear (n = 5) or ill defined (n = 3). Unenhanced CT scans showed a low density (n = 4), isodensity (n = 3), or a slightly high density (n = 1). The density noted on the unenhanced CT scans was homogeneous (n = 7) or heterogeneous (n = 1). The contrast-enhanced scans showed ring enhancement (n = 3) or significantly heterogeneous enhancement (n = 4), and the type of enhancement was persistent (n = 6) or washout (n = 1).

CONCLUSION

IMTs in the urinary system commonly occur in the superior wall or the front wall of the bladder. The observation that polypoid nodules on the bladder walls show ring enhancement on contrast-enhanced CT may be valuable in the diagnostic imaging of IMTs of the urinary system.

Inflammatory Myofibroblastic Tumors: Current Update

Inflammatory myofibroblastic tumor (IMT) is a mesenchymal neoplasm of intermediate biological potential with a predilection for the lung and abdominopelvic region. IMT represents the neoplastic subset of the family of inflammatory pseudotumors, an umbrella term for spindle cell proliferations of uncertain histogenesis with a variable inflammatory component. IMTs show characteristic fasciitis-like, compact spindle cell and hypocellular fibrous histologic patterns and distinctive molecular features. Imaging findings reflect pathologic features and vary from an ill-defined, infiltrating lesion to a wellcircumscribed, soft tissue mass owing to variable inflammatory, stromal, and myofibroblastic components.

Genetics of Bladder Malignant Tumors in Childhood

Bladder masses are represented by either benign or malignant entities. Malignant bladder tumors are frequent causes of disease and death in western countries. However, in children they are less common. Additionally, different features are found in childhood, in which non epithelial tumors are more common than epithelial ones. Rhabdomyosarcoma is the most common pediatric bladder tumor, but many other types of lesions may be found, such as malignant rhabdoid tumor (MRT), inflammatory myofibroblastic tumor and neuroblastoma. Other rarer tumors described in literature include urothelial carcinoma and other epithelial neoplasms. Rhabdomyosarcoma is associated to a variety of genetic syndromes and many genes are involved in tumor development. PAX3-FKHR and PAX7-FKHR (P-F) fusion state has important implications in the pathogenesis and biology of RMS, and different genes alterations are involved in the pathogenesis of P-F negative and embryonal RMS, which are the subsets of tumors most frequently affecting the bladder. These genes include p53, MEF2, MYOG, Ptch1, Gli1, Gli3, Myf5, MyoD1, NF1, NRAS, KRAS, HRAS, FGFR4, PIK3CA, CTNNB1, FBXW7, IGF1R, PDGFRA, ERBB2/4, MET, BCOR. Malignant rhabdoid tumor (MRT) usually shows SMARCB1/INI1 alterations. Anaplastic lymphoma kinase (ALK) gene translocations are the most frequently associated alterations in inflammatory myofibroblastic tumor (IMT). Few genes alterations in urothelial neoplasms have been reported in the paediatric population, which are mainly related to deletion of p16/lnk4, overexpression of CK20 and overexpression of p53. Here, we reviewed available literature to identify genes associated to bladder malignancies in children and discussed their possible relationships with these tumors.

Follow-Up Imaging of Inflammatory Myofibroblastic Tumor of the Uterus and Its Spontaneous Regression

Inflammatory myofibroblastic tumor (IMT) is an aggressive benign mass that may arise from various tissues and organs with a great variability of histological and clinical appearances. Due to variable and nonspecific imaging findings, diagnosis of IMT is not obtained before surgery. The aim of this paper is to present CT and MRI findings during four-year follow-up of complete, spontaneous regression of IMT of the uterus. The diagnosis was made by histology and immunohistochemistry analysis of the open excisional biopsy specimen. At that time, the organ of origin was not specified. After analysis of the follow-up imaging findings and the mode of tumor regression, the uterus was proclaimed as the probable site of origin. IMT of the uterus is extremely rare and has been reported in ten cases up to now. The gradual, complete regression of uterine IMT documented by CT and MRI may contribute to understanding of its nature.

MRI characterization of inflammatory myofibroblastic tumors in the maxillofacial region

PURPOSE

We aimed to investigate the magnetic resonance imaging (MRI) appearance of inflammatory myofibroblastic tumors (IMTs) in the maxillofacial region in order to improve diagnostic quality and resection efficacy.

MATERIALS AND METHODS

Ten cases of pathologically identified IMTs were analyzed by MRI. The MRI features were examined, including tumor location, tumor shape, tumor margins, and involvement of the surrounding tissues.

RESULTS

Of ten masses investigated in this study, eight masses were irregular neoplasms with unclear margins and two masses, in the parotid gland, were regular neoplasms with clear margins. Precontrast T1-weighted images of all ten masses exhibited isointense signals compared to the adjacent tissue, while contrast-enhanced T1-weighted images showed strong enhancement. Six masses were hypointense and four masses were slightly hyperintense in T2-weighted images. Involvement of the adjacent structures was observed in eight of ten cases. Meanwhile, two patients experienced intracranial involvement.

CONCLUSION

IMTs are rare tumors in the maxillofacial region, displaying a number of distinct MRI characteristics. Most importantly, they display low T2 signal intensity and strong enhancement, and they frequently invade surrounding structures. Thus, MRI can improve the accuracy of IMT diagnoses and provide critical information for surgical planning.

Imaging of childhood inflammatory myofibroblastic tumor

BACKGROUND

Inflammatory myofibroblastic tumor is a rare benign neoplasm and most commonly involves the lung but occurs in extrapulmonary locations.

OBJECTIVE

To present imaging findings in inflammatory myofibroblastic tumors in children based on a single-centre experience.

MATERIALS AND METHODS

We retrospectively reviewed CT and MRI findings of children diagnosed with inflammatory myofibroblastic tumor in a single institution.

RESULTS

We identified 15 children (range: 1-17 years) with inflammatory myofibroblastic tumor. The tumor was localized to the lung (n = 5), mediastinum (n = 3), trachea (n = 1), bronchus (n = 1), abdomen (n = 2) and orbit (n = 3). All the extraorbital tumors were solid masses with homogeneous or heterogeneous enhancement. Four lung tumors and one posterior mediastinal tumor contained calcification. Local recurrence following surgical removal occurred in two children with invasion of the esophagus and of the left atrium in one. Localized masses were seen in all children with orbital tumour. Two of these had episcleritis and perineuritis; one had episcleritis, tendonitis, perineuritis, myositis and dacryoadenitis.

CONCLUSION

The locations and imaging features of inflammatory myofibroblastic tumors are variable.

A Renal Inflammatory Myofibroblastic Tumor Similar to Cystic Renal Cell Carcinoma: One Case Report

We describe and analyze the clinical course and imaging findings of a case of a renal inflammatory myofibroblastic tumor (IMT) that is similar to cystic renal cell carcinoma. "Solitary cysts" on the left kidney were found during a health examination of a 60-year-old female. The patient also had hypertension. She had undergone surgeries twice for limb trauma fracture and had no definite record of hepatitis. There was no tenderness with percussion of the kidney area or edema in the lower extremity. The renal function results, including serum creatinine, blood urea nitrogen, and blood urea, were within the normal range. No gross hematuria or microscopic hematuria was found. An 8.7  cm × 9.2  cm mixed echogenic mass at the upper pole of the left kidney was observed with ultrasound, the majority of which was an anechoic mass that was slightly protruding from the renal capsule and had well-circumscribed borders. After a bolus injection of an ultrasound contrast agent, the mass had rapid enhancement with fast fading. An approximately 9.4  cm × 10.1  cm round-like cyst lesion at the upper pole of the left kidney was revealed by computed tomography (CT) examination of the abdomen; it had edge finishing with well-circumscribed borders. The upper inner wall of the lesion was thick with crescentic soft tissue. The solid content had gradual enhancement on enhanced CT scans. A kidney tumor was considered based on the CT findings. Based on the preoperative examination, the left renal cystic masses were resected. Intraoperative frozen sections were used to further clarify the nature of the lesion, and no significant malignant cells were observed; therefore, the kidney was not removed. The pathological diagnosis was renal IMT. After surgery, the patient recovered and did not have recurrence or metastasis over the course of long-term follow-up. CT images of our patient with renal cystic disease are categorized as Fuhrman grade IV and typically indicate the presence of malignant lesions. However, gradual enhancement of the solid content in our case is different from typical cystic renal cell carcinoma. The nature of the lesion was further identified using intraoperative frozen sections, which helped avoid unnecessary nephrectomy.

Inflammatory pseudotumor of the urinary bladder

We report a case of an inflammatory pseudotumor of the urinary bladder in a 31 year-old woman. She presented at the emergency room with low abdominal pain and urinary symptoms. Abdominal ultrasound, computed tomography and magnetic resonance imaging were performed and revealed asymmetric thickening of the urinary bladder wall. Cystoscopy with urinary cytology revealed a benign nature of the process. The patient underwent partial cystectomy and the pathologic examination of the specimen revealed an inflammatory pseudotumor. We reviewed the clinical, imaging and pathological features of the inflammatory pseudotumor of the urinary bladder and discussed its differential diagnosis.

Plasma cell granuloma of the urinary bladder: A pseudotumor - A clinical dilemma

Plasma cell granuloma is a rare benign proliferative lesion that often mimics a malignant mass clinically and radiologically and its presentation in the urinary bladder is exceptional. Presuming malignant mass, such lesions often receive radical treatment. We are presenting here one such tumor, which resembled as an urachal tumor and underwent partial cystectomy.

Algorithmic approach to solid adnexal masses and their mimics: utilization of anatomic relationships and imaging features to facilitate diagnosis

Solid adnexal masses, while less common than their cystic counterparts, may present a challenge for radiologists given the wide range of histologic entities that occur in this region. Pelvic masses, especially when large, can seem overwhelming at first but application of an algorithmic approach allows for more confident assessment. This approach focuses first on the use of anatomic relationships and interactions of various pelvic structures to localize the mass' origin. For instance, the directionality of ureteral displacement can suggest if a mass is intra or extraperitoneal. Then, key discriminating imaging features, such as the presence of fat, hypervascularity, or low T2 signal on magnetic resonance imaging (MRI) can be applied to further narrow the list of diagnostic possibilities. Entities such as leiomyomas, nerve sheath tumors, congenital uterine anomalies, and vascular abnormalities (ovarian torsion or iliac vessel aneurysm) in particular are often accurately characterized with sonography and/or MRI. For solid adnexal masses in which a definitive diagnosis by imaging is not reached, information germane to clinicians regarding further management can still be provided, principally with regard to surgical vs. nonsurgical treatment.

Low-grade myofibroblastic proliferations of the urinary bladder

CONTEXT

Myofibroblastic proliferations of the urinary bladder, which share some similarities with nodular fasciitis, were first reported in 1980. Since then, they have had several designations, the most frequently used being inflammatory myofibroblastic tumor. Based on both histopathologic and prognostic grounds, some authors prefer the term pseudosarcomatous myofibroblastic proliferation, at least for some of the proliferations. These same scientists also assimilate the so-called postoperative spindle cell nodules with the pseudosarcomatous myofibroblastic proliferations. Little is known about these low-grade myofibroblastic proliferations.

OBJECTIVES

To review the literature about low-grade myofibroblastic proliferations occurring in the urinary bladder.

DATA SOURCES

Textbooks and literature review. We obtained most of the clinicopathologic peculiarities from a patient population composed of the most-relevant, previously reported cases.

CONCLUSIONS

The low-grade myofibroblastic proliferations of the urinary bladder are rare lesions affecting males more often than they do females. The most-common signs and symptoms are hematuria and dysuria. Histopathologically, they are spindle cell proliferations in a loose myxoid stroma, even though compact proliferations or hypocellular fibrous patterns can be found. Immunohistochemistry is quite nonspecific, except for ALK-1 positivity (20%-89%). Fluorescence in situ hybridization has demonstrated clonal genetic aberrations involving the ALK gene in 50% to 60% of cases. After surgery, only 6% of patients experience local recurrence, without metastases or deaths from the disease. Malignant transformation has been reported exceptionally. These myofibroblastic proliferations are probably part of a continuum with, at one end, benign pseudosarcomatous proliferations and, at the opposite end, more-aggressive lesions. Because of the frequently indolent clinical course, aggressive treatment would be unjustified.

Inflammatory myofibroblastic tumor with extensive involvement of the bladder in an adolescent: a case report

Inflammatory myofibroblastic tumor (IMT) is a rare lesion of unclear pathogenesis that shows a wide, highly variable spectrum of clinical behavior. We describe the case of a 17-year-old boy with a large IMT that infiltrated the bladder, ileocecal junction, peritoneum and pelvic retroperitoneal space. The tumor was associated with extensive toughening and thickening of the bladder, and, although it showed a tendency for invasive growth, it affected mainly the bladder and adjacent tissue. To the best of our knowledge, this case report is the first to describe an IMT involving the entire bladder and several adjacent pelviabdominal organs. The bladder wall was tough and could hardly be cut by scalpel. Levels of inflammatory response markers such as C-reactive protein fell after surgery.

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.

IgG4-related disease of the ureter: report of two cases and review of the literature

IgG4-related disease (IgG4-RD) is a recently recognized multi-organ fibro-inflammatory lesion characterized by elevated IgG4 serum levels and mass-forming lesions. This condition shows similar histological features independently of the site of origin including storiform fibrosis, obliterative phlebitis, and dense lymphoplasmacytic infiltrate with a conspicuous IgG4-positive plasma cell component. Since this disease has only recently been categorized as a single specific nosologic entity, lesions with these typical morphological features have previously been named in different ways, creating some confusion and making it difficult to identify cases published in the literature. Lesions with features suggesting IgG4-RDs have very rarely been reported in the ureter, and they have been named using the terms "inflammatory pseudotumor" and "idiopathic segmental ureteritis." Herein, we describe the clinicopathological features of ureteral IgG4-RD found in two different patients. An 82-year-old female and a 77-year-old male underwent ureteral resection due to severe ureteral wall thickness and lumen stenosis suggestive of urothelial carcinoma. However, histological examinations showed transmural fibro-inflammatory lesions, with abundant IgG4 plasma cells intermixed with histiocytes, lymphocytes, fibroblasts, and scattered eosinophils. We have also accurately reviewed the literature in order to identify, among lesions diagnosed with different names, examples of ureteral IgG4-related lesions to give the reader a comprehensive overview of this relatively rare inflammatory disease. We suggest using the name "ureteral IgG4-RD" for those lesions showing the same morphological features as IgG4-RDs located elsewhere.

Pediatric renal inflammatory myofibroblastic tumours: A case report and review of the etiology and management options

Inflammatory myofibroblastic tumours (IMTs) have been described in lung, bladder, spleen, breast, pancreas, liver, colon, spermatic cord, prostate, peripheral nerves, orbit and kidney. Traditionally believed as having a reactive pathogenesis, IMTs are now viewed more as a neoplasm. This report describes a case of a renal IMT in a 14-year-old girl with spina bifida associated neurogenic bladder and a history of recurrent urinary tract infections. This represents a unique case as pediatric renal IMTs are very rare in the literature. We discuss how this patient was managed and how she presented compared to other reported cases.

Immunoglobulin G4-related sclerosing disease involving the urethra: case report

Immunoglobulin G4 (IgG4)-related sclerosing disease is a systemic disease characterized by extensive IgG4-positive plasma cells and T-lymphocyte infiltration in various organs. We described the imaging findings of an IgG4-related inflammatory pseudotumor in the urethra. The urethral mass showed isoattenuation on unenhanced CT images, delayed enhancement on enhanced CT images, iso- to slight hyper-intensity on T1 and T2 weighted magnetic resonance images, diffusion restriction on diffusion weighted images, and heterogeneously low echogeneity on ultrasonography.

Urologic manifestations of inflammatory pseudotumor: Report of 2 cases and review of the literature

We report two adult patients with varied urologic symptoms who were found to have inflammatory pseudotumor on histopathology. The first patient had a large, solid, enhancing retroperitoneal mass lesion and presented with increased frequency of urination and recurrent urinary tract infections. The second patient had an obstructing left distal ureteric stricture and presented with painless hematuria. Though preoperative radiological diagnosis of this entity is not feasible, the present article illustrates the imaging findings in this unusual disease entity with review of the relevant literature.

Plasma Cell Granuloma of the Thyroid Gland

This study reports a case of plasma cell granuloma of the thyroid gland in a 47-year-old woman, presenting with a right subhyoid mass and a previous diagnosis of Hashimoto thyroiditis dating back to 1988, which was made on a subtotal thyroidectomy. Plasma cell granuloma preferentially involves the lung, with only 18 cases of thyroid gland involvement having been reported to date in the English literature. Thyroid plasma cell granuloma preferentially affects women and classically shows a prominent plasma cell infiltrate embedded in a variable degree of fibrous stroma: only 2 of the reported cases exhibited the morphologic features of inflammatory myofibroblastic tumor. These morphologic features may raise problems in the differential diagnosis with other plasma cell–rich disorders, including infectious diseases and auto(dys)immune conditions, including the recently described “IgG4-related sclerosing disease.” In view of these considerations, a contemporary diagnostic approach to thyroid plasma cell granuloma is therefore discussed here.

Inflammatory pseudotumor of the kidney

Inflammatory pseudotumor of the kidney is a rare benign condition with unknown etiology that can mimic malignancy. We report a case of inflammatory pseudotumor of the kidney. A 59-year-old male patient was admitted with a complaint of right flank pain and hematuria. Ultrasonography and magnetic resonance imaging of the patient revealed a 9 cm × 10 cm mass originating from the renal parenchyma with posterior extension. Operative findings revealed a mass adhering to the psoas muscle. Histopathologic examination demonstrated spindle-shaped fibroblast cells accompanying inflammatory cells. The pathological diagnosis was renal inflammatory pseudotumor. Repeated US and computed tomography revealed complete remission.

Inflammatory pseudotumor of the kidney: a case report

Introduction

Inflammatory pseudotumors, also known as inflammatory myofibroblastic tumors, are uncommon benign tumors of unknown etiology which may develop at several anatomical sites. In the urogenital tract, inflammatory pseudotumor usually affects the urinary bladder or the prostate. Inflammatory pseudotumor of the kidney is very rare. It is considered as a reactive inflammatory lesion that features very good prognosis.

Case presentation

We present the case of a 57-year-old Moroccan man who presented with a two-month history of gross hematuria and left lumbar pain. Imaging investigations revealed a left kidney mass and pathological examination of the nephrectomy specimen showed an inflammatory pseudotumor.

Conclusion

As the preoperative definitive diagnosis of such a tumor is not possible, surgery is advised because only pathological examination of the nephrectomy specimen can establish the diagnosis with certainty. From one case report and literature review, the authors suggest a diagnostic and therapeutic strategy for the management of this rare tumor.

Inflammatory pseudotumor (myoblastic tumor) of the breast: a case report and review of the literature

Inflammatory pseudotumor of the breast is a very rare cause of breast mass. To our knowledge, only a few cases have been described in the English literature. In this case, the lesion appeared on mammography as a round high-density mass with ill-defined margins and on sonography as an irregular mass of complex echogenicity with ill-defined margins and an echogenic rim. The lesion was resected with no evidence of local recurrence after 3 years.

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.