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

Multidetector computed tomography evaluation of bladder lesions

Background

Urinary bladder tumors are the most common type of tumors detected in patients with gross hematuria. Multidetector computed tomography (MDCT) is an accurate method for detecting bladder lesions. This review aims to describe the features of MDCT and the possible values for distinguishing these lesions in the bladder.

Main body

In this review, we discuss the role of MDCT in the evaluation of patients with bladder cancer and describe a broad spectrum of bladder lesions, including malignant bladder lesions beyond bladder cancer, benign bladder lesions, and diffuse bladder wall thickening.

Short conclusion

Familiarity with the clinical presentations and imaging features of bladder lesions can lead to more accurate diagnosis and appropriate management.

Urinary Bladder Masses, Rare Subtypes, and Masslike Lesions: Radiologic-Pathologic Correlation

Urinary bladder masses are commonly encountered in clinical practice, with 95% arising from the epithelial layer and rarer tumors arising from the lamina propria, muscularis propria, serosa, and adventitia. The extent of neoplastic invasion into these bladder layers is assessed with multimodality imaging, and the MRI-based Vesical Imaging Reporting and Data System is increasingly used to aid tumor staging. Given the multiple layers and cell lineages, a diverse array of pathologic entities can arise from the urinary bladder, and distinguishing among benign, malignant, and nonneoplastic entities is not reliably feasible in most cases. Pathologic assessment remains the standard of care for classification of bladder masses. Although urothelial carcinoma accounts for most urinary bladder malignancies in the United States, several histopathologic entities exist, including squamous cell carcinoma, adenocarcinoma, melanoma, and neuroendocrine tumors. Furthermore, there are variant histopathologic subtypes of urothelial carcinoma (eg, the plasmacytoid variant), which are often aggressive. Atypical benign bladder masses are diverse and can have inflammatory or iatrogenic causes and mimic malignancy. ^© RSNA, 2022 Online supplemental material is available for this article.

Inflammatory Myofibroblastic Tumor of the Urinary Bladder: An 11-Year Retrospective Study From a Single Center

Purpose

To share our experience in the diagnosis and treatment of an inflammatory myofibroblastic tumor of the urinary bladder (IMTUB).

Materials and Methods

A database searches in the pathology archives by using the term “inflammatory myofibroblastic tumor” and” bladder” in our hospital department of pathology from 2010 to 2021. Patient characteristics, clinical features, histopathological results, immunohistochemical staining results, and treatment outcomes were reviewed.

Results

Fourteen cases of IMTUB were retrieved. The mean age was 44.7 ± 18.9 years (range 12–74). Nine (64.3%) of the patients presented with hematuria, followed by seven (50%) with odynuria, five (35.7%) with urgent urination, and one (7.1%) with dysuria. Ten (71.4%) of the patients were treated with partial cystectomy (PC), three (21.4%) with transurethral resection of bladder tumor (TURBT), and one (7.1%) with radical cystectomy (RC). Histopathologically, eight (57.1%) had a compact spindle cell pattern. Anaplastic lymphoma kinase (ALK) staining was positive in six (75%) of 8 cases. During a mean follow-up period of 43.9 ± 38 months (range 3–117), a patient had recurrence within half a month. Then, the patient was treated with further TURBT surgery and had no recurrence within 6 months. Thirteen of the patients had no local recurrence or distant metastasis.

Conclusion

Inflammatory myofibroblastic tumor of the urinary bladder (IMTUB) is clinically rare and has a good prognosis. The disease is mainly treated with surgery to remove the tumor completely. It can easily be misdiagnosed as bladder urothelial carcinoma, leiomyosarcoma, or rhabdomyosarcoma, which may result in overtreatment and poor quality of life of patients.

Clinicopathological analysis and outcomes of inflammatory myofibroblastic tumours of the urinary bladder

OBJECTIVES

To describe clinical, imaging, and histopathological characteristics of inflammatory myofibroblastic tumour (IMT) of the urinary bladder and provide initial management and surveillance recommendations.

PATIENTS AND METHODS

We identified patients with IMT of the bladder treated at our facility from 1998 to 2020. Categorical variables were analysed with chi-square and Fisher's exact tests and continuous variables with the Mann-Whitney U-test. Kaplan-Meier analysis was performed for recurrence-free survival.

RESULTS

IMT was diagnosed in 35 patients with median (interquartile range [IQR]) follow-up of 20 (11.5-68.5) months. At initial diagnosis 86% were clinically organ-confined, 9% locally advanced, and 5% metastatic. Majority of patients (92%) had residual disease on re-staging transurethral resection (TUR). Of the 15 patients with organ-confined disease managed initially with TUR alone, five (33%) recurred at a median (IQR) of 5 (3.0-5.5) months from initial diagnosis. Presentation with visible haematuria was associated with recurrence (100% in recurrence vs 40% in non-recurrence groups, P = 0.044). There were no patients who developed a recurrence beyond 6 months after diagnosis. Partial or radical cystectomy was required in 23% and 9% of patients, respectively. One patient presented with metastatic disease associated with anaplastic lymphoma kinase (ALK) translocation and achieved a durable complete remission with 7 months of crizotinib therapy.

CONCLUSIONS

No patient with IMT treated with aggressive endoscopic management developed recurrences beyond 6 months. There were additionally no recurrences noted after definitive radical or partial cystectomy. These data support organ sparing therapy with aggressive endoscopic management and short-term surveillance in patients with localised IMT, with extirpative surgery reserved for refractory cases.

A rare case of inflammatory myofibroblastic tumor of the vulva in a newborn

Inflammatory myofibroblastic tumor (IMT) is an uncommon neoplasm that rarely arises in the genitourinary system. IMTs in the vulva in infants are extremely rare in the literature. The tumor consists of myofibroblastic spindle cells accompanied by inflammatory cell infiltration. In this article, we aimed to describe the case of IMT in the vulva. A newborn girl presented with a mass in the vulva detected in the prenatal period. The patient was treated with surgery and chemotherapy. Follow-up 8 months after surgery showed no signs of recurrence. In conclusion, IMT has a variable clinical presentation, surgery is the optimal approach, but in cases without complete resection, chemotherapy is essential.

Inflammatory myofibroblastic tumours of the thorax: Radiologic and clinicopathological correlation

CONTEXT AND AIMS

Inflammatory myofibroblastic tumour (IMT) is a rare mesenchymal neoplasm with intermediate malignant potential. The aim of this study is to describe and compare the clinical presentation, computed tomography (CT) findings and anaplastic lymphoma kinase -1 (ALK-1) expression of IMT of the thorax in children and adults. We also sought to study the tumour behaviour after treatment on the follow-up imaging.

MATERIALS AND METHOD

This is a retrospective observational study of 22 histopathologically proven cases of IMT in the thorax. The clinical parameters, CT findings, biopsy results, treatment received and follow-up were recorded. Statistical analysis was performed using Fisher's exact test.

RESULTS

IMT of the thorax had diverse imaging appearances, presenting either as large invasive lung masses with or without calcifications or as smaller endobronchial lesions. Children commonly presented with long duration fever (P = 0.02) and large invasive lung masses (P = 0.026), whereas adults presented with long duration haemoptysis (P = 0.001) and endobronchial lesions or smaller lung parenchymal lesions. Calcifications were more common in children (P = 0.007). ALK-1 was positive in 40% of children and 18.2% of adults (P = 0.547). Endobronchial lesions showed a trend for ALK-1 negativity. Patients with bronchoscopic excision had local recurrence and patients with surgical wedge resection had metastatic brain lesions as compared to those with lobectomy and pneumonectomy (P = 0.0152). A patient with unresectable lung mass had malignant transformation to spindle cell sarcoma after 9.5 years.

CONCLUSIONS

Thoracic IMT presents with some distinct clinical and CT findings in adults and children. The CT findings and management options have implications for prognosis. If resectable, lobectomy is a better option than wedge resection or bronchoscopic excision for preventing local recurrence and metastasis. IMT can undergo malignant transformation.

Rare presentation of inflammatory myofibroblastic tumor in the kidney

Inflammatory myofibroblastic tumor (IMT) is a rare pathologic entity that has been mostly described in the lung. It has been reported in nearly every organ, with occurrence in the kidney being extremely rare. IMT has nonspecific clinical and radiological findings and often mimics a malignant process. This is a case discussing the radiologic and pathologic findings of a renal IMT in a 35-year-old female who underwent radical nephrectomy for a right renal pelvis mass that was mistaken for transitional cell carcinoma.

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.

Transurethral Resection for the Treatment of an Inflammatory Myofibroblastic Tumor of the Urinary Bladder: A Case Report

Inflammatory myofibroblastic tumors (IMT) of the urinary bladder is a remarkably rare bladder tumor. To this day, no standardized treatment protocol has been recognized. Here we report a case of bladder IMT in a 14-year-old girl presenting with urgency, frequency, and gross painless hematuria for a week. Complete excision of the bladder IMT was amenable with transurethral resection of bladder tumor (TURBT). Follow-up cystoscopy did not detect any recurrence. Minimally invasive bladder-sparing treatments are a valid option for treating IMT of the bladder.

Inflammatory myofibroblastic tumor of urinary bladder with severe hematuria: A Case report and literature review

RATIONALE

Inflammatory myofibroblastic tumor (IMT) is a rare intermediate soft tissue tumor. Rarely occurring in the urinary bladder, MTs is composed of myofibroblast differentiated spindle cells and accompanied by numerous inflammatory cells, plasma cells and/or Lymphocytes.

PATIENT CONCERNS

A 28-year-old female, with history of 2 cesarean sections 8 years ago and 2 years ago, was admitted to the emergency department for a 7-day ongoing gross hematuria with clots.

DIAGNOSES

A cystoscopy showed a tumor near the bladder neck, computed tomography (CT) showed a mass and massive blood clots in the bladder. Finally, postoperative pathological examination confirmed a diagnosis of inflammatory myofibroblastic tumor of bladder.

INTERVENTIONS

The patient was given rehydration and blood transfusion to improve the general condition. Then, emergency transurethral resection of the bladder tumor was performed.

OUTCOMES

No metastases to lymph nodes and other organs were found, and no tumor progression was revealed during 3-months of follow-up.

LESSONS

IMTs rarely occur in the urinary bladder. Due to the lack of specificity in clinical symptoms, it's difficult to arrive at a definite diagnosis before operation. Therefore, usually, the final diagnosis depends on histomorphological features and the immunohistochemical profile. Further case studies are required to study the biological behavior of this condition.

Minimally invasive surgery for inflammatory myofibroblastic tumor of the urinary bladder: Three case reports

RATIONALE

Inflammatory myofibroblastic tumors of the urinary bladder (IMTUB) is exceptionally rare. Currently, no standardized treatment has been established for IMTUBs.

PATIENT CONCERNS

Herein we report three cases presenting with hematuria and anemia. A 25-year-old man experienced painless gross hematuria for 2 days and the hemoglobin level continuously dropped to 88 g/L; a 72-year-old man complaining of gross hematuria for seven days; and a 33-year-old woman presenting with gross hematuria, urgency, and frequency for the duration of 20 days, with a hemoglobin level of 61 g/L.

DIAGNOSIS

Ultrasonography, contrast-enhanced computed tomography (CT) scan and magnetic resonance image (MRI) indicated masses of different sizes on the walls of the urinary bladders. Diagnostic transurethral resection of bladder tumor (TURBT) was performed which revealed the diagnosis of IMTUB.

INTERVENTIONS

In our cases, we removed the tumors completely with a minimally invasive approach. The first patient received TURBT only. The other patients underwent further laparoscopic and robot-assisted laparoscopic partial cystectomy respectively for the incomplete resection of tumor by diagnostic TURBT.

OUTCOMES

Histology of the resected specimen had proliferation of spindle cells with inflammation consistent with IMTUB. Immunohistochemical staining revealed that the tumor cells were positive for anaplastic lymphoma kinase (ALK), Vimentin and Ki-67 (20%-40%), negative for smooth muscle actin (SMA), S-100 and desmin confirming the diagnosis of IMTUB. Follow-up cystoscopy and CT or MRI (mean follow-up period: two years) did not detect any local recurrence or distant metastasis.

LESSONS

Bladder-sparing treatment by TURBT or partial cystectomy remains the main mode of treatment for IMTUB. Laparoscopic and robot-assisted laparoscopic approach is safe and may yield satisfactory oncological and functional results. Regular follow-up protocol is necessary after operation.

Inflammatory myofibroblastic tumor of the pleura with adjacent chest wall invasion and metastasis to the kidney: a case report

BACKGROUND

Inflammatory myofibroblastic tumor is a rare benign neoplasm that frequently involves the lung and abdominopelvic region, and is found mainly in children and young adults. Inflammatory myofibroblastic tumor tends to be locally invasive or recurrent, and rarely metastasizes.

CASE PRESENTATION

A 76-year-old Korean man presented with a history of upper back pain for 2 months and motor weakness in both lower extremities for 2 days. Contrast-enhanced computed tomography of his chest and abdomen showed a large heterogeneous pleural mass involving the right fifth rib and vertebral body and a mass infiltrating the right renal hilum. Computed tomography-guided percutaneous needle biopsy of the pleural mass was performed. The histological findings on hematoxylin and eosin staining showed proliferation of spindle cells with infiltration of lymphocytes and plasma cells. Immunohistochemistry showed neoplastic cells positive for CD68, focally positive for smooth muscle actin, and negative for cytokeratin and desmin. Inflammatory myofibroblastic tumor was diagnosed based on the histological examination. Treatment with glucocorticoids (methylprednisolone 1 mg/kg) and radiotherapy (5 days/week for 3 weeks at 3 Gy/fraction, 45 Gy/15 days) was started. After 1 month, chest computed tomography showed a reduction in the size of the pleural mass, and abdominopelvic computed tomography showed decreased infiltration around the right renal pelvis.

CONCLUSIONS

Inflammatory myofibroblastic tumor is a rare neoplasm of intermediate malignant potential due to a tendency for local recurrence and it rarely develops distant metastases. Complete surgical resection is the primary treatment. However, unresectable and metastatic inflammatory myofibroblastic tumor can be treated with systemic therapy, including glucocorticoids, radiotherapy, and/or chemotherapy.

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.