Rare pseudotumors of the urinary bladder in childhood

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.

Coexistence of inflammatory pseudotumour and pseudomembranous cystitis: a histopathological surprise

We report a case of inflammatory pseudotumour (IP) and pseudomembranous cystitis (PC) in a young female patient who presented with gross haematuria and clot retention. Cystoscopy revealed a single glistening, polypoid growth of approximately 3 cm × 2.5 cm at the left lateral wall and the trigone of the urinary bladder. She was treated by transurethral resection of bladder mass. The patient's symptoms significantly improved after surgery. Histopathology report revealed haphazardly arranged myofibroblasts, fibroblasts and histiocytes and discrete areas of non-keratinising squamous metaplasia that was suggestive of IP coexistence with PC. She was doing well during the follow-up period of 12 months. Cystoscopy taken at 3 monthly intervals did not show any evidence of tumour recurrence.

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.

Cystic lymphangioma of the pancreas

Lymphangioma is a benign form of neoplasm arising from the lymphatic system. It occurs as a result of congenital malformations of the lymphatics leading to the obstruction of local lymph flow and the development of lymphangiectasia. Lymphangiomas are common in pediatric patients, in the soft tissues of the neck and the axillae, but lymphangioma of the pancreas is extremely rare, accounting for less than 1% of these tumors. It occurs more frequently in females and is often located in the distal pancreas. Although extremely rare, cystic lymphangioma of the pancreas should be taken into consideration as a differential diagnosis of pancreatic cystic or retroperitoneal lesions, especially in women. Herein, we report on a case of cystic lymphangioma of the distal pancreas in a 37-year-old woman who was treated with complete surgical resection with a review of the literature.

Cystic lymphangioma of the pancreas mimicking pancreatic pseudocyst

Lymphangiomas are rare congenital benign tumors arising from the lymphatic system, and are mostly encountered in the neck and axillary regions of pediatric patients (95%). Lymphangioma of the pancreas is extremely rare accounting for less than 1% of these tumors. We report here on a case of pancreatic cystic lymphangioma. A 54-year-old woman presented with intermittent postprandial abdominal discomfort and radiating back pain. Abdominal computed tomography scan revealed 8 × 6.5 cm hypodense cystic mass arising from the tail of the pancreas without septa or solid component. The initial impression was a pancreatic pseudocyst. The patient underwent distal pancreatectomy with splenectomy. The histopathologic and immunohistochemical study helped make the diagnosis of a pancreatic cystic lymphangioma. Herein, we report a case of pancreatic cystic lymphangioma mimicking pancreatic pseudocyst and review the relevant medical literature.

A pictorial review of imaging of abdominal tumours in adolescence

Neoplastic abdominal tumours, particularly those originating from embryonal tissue (such as hepatoblastoma and nephroblastoma) and neural crest cells (such as neuroblastoma), are well-documented in young children. Neoplasms of adulthood, most commonly carcinoma of different visceral organs, are also well-documented. Abdominal tumours in adolescence constitute a distinct pathological group. The radiological features of some of these tumours have been described only in isolated reports. The purpose of this pictorial essay was to review the imaging findings of various kinds of abdominal tumours in adolescent patients (with an age range of 10-16 years) who presented to the Children Cancer Center of our institution in the past 15 years. Some tumours, though rare, have characteristic imaging appearances (especially in CT) that enable an accurate diagnosis before definite histological confirmation.

Radiological appearance of inflammatory myofibroblastic tumour

Inflammatory myofibroblastic tumour (IMFT) is a distinct entity with variable clinical presentation and therapeutic options. We present three paediatric cases of IMFT, originated from the lung, bladder and ovary respectively. All lesions were heterogeneous, with mixed solid/cystic components and infiltrative pattern, and were interpreted as aggressive malignant neoplasms initially due to their bizarre imaging appearance. The definitive diagnosis was derived from characteristic histopathological features.

Successful Preoperative Treatment of Pediatric Bladder Inflammatory Myofibroblastic Tumor with Anti-Inflammatory Therapy

Inflammatory myofibroblastic tumors are rare, locally invasive tumors that can involve the genitourinary tract. Therapy has consisted primarily of surgery, and anecdotal experience using both chemotherapy and radiotherapy, which have yielded unimpressive results. We report the first case of a bladder inflammatory myofibroblastic tumor that responded to an anti-inflammatory regimen (prednisone and Cox-2 inhibitor) before surgical extirpation.

Inflammatory myofibroblastic tumors of the urinary tract: a clinicopathologic study of 46 cases, including a malignant example inflammatory fibrosarcoma and a subset associated with high-grade urothelial carcinoma

Inflammatory myofibroblastic tumor (IMT) of the urinary tract, also termed postoperative spindle cell nodule, inflammatory pseudotumor, and pseudosarcomatous fibromyxoid tumor, is rare and in the past was believed to reflect diverse entities. We reviewed a series of 46 IMTs arising in the ureter, bladder, and prostate, derived primarily from a large consultation practice. There were 30 male and 16 females aged 3 to 89 years (mean 53.6). Lesions were 1.2 to 12 cm (mean 4.2). There was a history of recent prior instrumentation in 8 cases. Morphology was similar to that previously described for IMT occurring in this region, with the exception of 1 case that focally appeared sarcomatous. Polypoid cystitis coexisted in 5 patients (11%). Mitoses were typically scant (0 to 20/10 hpf, mean 1). Necrosis was seen in 14 (30%) cases. Invasion of the muscularis propria was documented in 19 (41%). By immunohistochemistry (IHC), lesions at least focally expressed anaplastic lymphoma kinase (ALK) (20/35, 57%), AE1/3 (25/34, 73%), CAM5.2 (10/15, 67%), CK18 (6/6, 100%), actin (23/25, 92%), desmin (15/19, 79%), calponin (6/7, 86%), caldesmon (4/7, 57%, rare cells), p53 (10/13, 77%), and most lacked S100 (0/14), CD34 (0/13), CD117 (2/13, 15%), CD21 (0/5), and CD23 (0/3). ALK gene alterations were detected by fluorescence in situ hybridization (FISH) in 13/18 (72%) tested cases, including 2 with prior instrumentation; 13/18 (72%) showed agreement between FISH ALK results and ALK protein results by IHC. Most bladder IMTs were managed locally, but partial cystectomy was performed as the initial management in 7 cases and cystectomy in 1 (1 IMT was initially misinterpreted as carcinoma, 1 IMT was found incidentally as a separate lesion in a cystectomy specimen performed for urothelial carcinoma). Follow-up was available in 32 cases (range 3 to 120 mo; mean 33; median 24). There were 10 patients with recurrences (2 with 2 recurrences). Recurrences were unassociated with muscle invasion or with ALK alterations. In 2 cases, tumors of the urinary tract (TURs) showing IMT preceded (1 and 2 mo, respectively) TURs showing sarcomatoid carcinoma with high-grade invasive urothelial carcinoma accompanied with separate fragments of IMT. Even on re-review the IMT in these 2 cases were morphologically indistinguishable from other cases of IMT, with FISH demonstrating ALK alterations in the IMT areas in one of them. Both these patients died of their carcinomas. Lastly, there was 1 tumor with many morphological features of IMT and an ALK rearrangement, yet overtly sarcomatous. This case arose postirradiation for prostate cancer 4 years before the development of the lesion, with tumor recurrence at 4 months and death from intra-abdominal metastatic disease at 9 months. In summary, urinary tract IMTs are rare and share many features with counterparts in other sites, displaying similar morphology and immunogenotypic features whether de novo or postinstrumentation. Typical IMTs can be locally aggressive, sometimes requiring radical surgical resection, but none of our typical cases metastasized, although they can rarely arise contemporaneously with sarcomatoid urothelial carcinomas. For these reasons, close follow-up is warranted.

In situ expression of T-helper type 2 immunoregulatory response in myofibroblast of a pediatric bladder inflammatory pseudotumor

Inflammatory pseudotumor (IP) is generally considered to be a non-neoplastic, inflammatory response despite its gross and microscopic features of spindle cell neoplasm. Reported herein is a case arising from the muscularis propria of the urinary bladder in a 14-year-old girl who presented with gross hematuria and impending hypovolemic shock. The tumor consisted of proliferating myofibroblastic cells and various types of inflammatory cells. The immunoregulatory responses and reactions were investigated with regard to infiltration of inflammatory mononuclear cells being a documented finding in IP. Immunhistochemical and in situ hybridization studies for cytokines showed that the myofibroblastic cells were positive for interleukin (IL)-4, IL-5 and negative for interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha expression. The patient has been free of disease since excision of the tumor 34 months ago. Thus, cytokine production in IP suggests that it is reactive in nature and myofibroblasts may be the source of cytokines in the pathogenic process.

Cardiac pseudosarcomatous fibromyxoid tumor: a review of the literature

A cardiac pseudosarcomatous fibromyxoid tumor (PFT) is described in a previously healthy 35-year-old man, together with a review of the literature. Pseudosarcomatous fibromyxoid tumor is within the spectrum of inflammatory (myofibroblastic) pseudotumors. It has previously been described predominantly within the genitourinary tract and respiratory tract. Inflammatory pseudotumor is rare as a cardiac tumor, and cardiac PFT is not previously reported. No recurrence or metastatic disease has been reported after resection of PFTs elsewhere in the body, and this tumor seems to have a benign clinical course.

[Pseudosarcomatous fibromyxoid tumor of the prostate: report of a case]

The authors report a case of pseudosarcomatous fibromyxoid tumor of the prostate. It is always a benign lesion, whose mains differentials diagnoses are sarcomas of the prostate. Diagnosis is based on histological examination. Treatment is surgical.