Unresectable infantile myofibroma discovered in utero.

The authors present a case of a proliferative nodule located beneath an infant's lower lip that was initially discovered on prenatal ultrasound and fetal magnetic resonance imaging (MRI). Biopsy revealed a smooth muscle actin-positive spindled cell proliferation with hemangiopericytoma-like vessels consistent with infantile myofibromatosis (IM). Since the location prevented surgical management, the clinicians opted to observe the lesion. Ultimately, the lesion fully regressed on its own confirming conservative management is an option for isolated IM.

Solitary intraosseous myofibroma: a rare case diagnosed from mandibular fracture.

Intraosseous myofibroma is a rare tumor of benign nature, slow growth, and low morbidity. The aim of this article is to report a case of pathologic fracture associated with the incidental diagnosis of myofibroma in the mandible of an adolescent. A 15-year-old girl reported that she experienced a physical assault resulting in facial injuries 1 month previously and had since experienced severe pain, malocclusion, and chewing difficulty. The cone beam computed tomographic examination revealed multiple features suggestive of pathologic fracture associated with a hypodense lesion with lobulated limits, as well as expansion and thinning of the cortical bone in the left mandible. The histopathologic diagnosis of the lesion indicated myofibroma. Treatment consisted of enucleation and curettage of the lesion with reduction and internal fixation of the fracture. After 18 months, the osteosynthesis plates and an impacted mandibular third molar were removed. Curettage of the lesion in association with treatment of the mandibular fracture proved to be effective for both bone consolidation and absence of recurrence while restoring mandibular functionality.

[Pediatric myofibroma/myofibromatosis of the soft tissue and bone: a clinicopathological analysis of 28 cases].

Objective: To investigate the clinicopathological features, diagnosis and differential diagnosis of pediatric myofibroma/myofibromatosis of the soft tissue and bone. Methods: All cases of pediatric myofibroma/myofibromatosis of the soft tissue and bone diagnosed between January 2011 and December 2018 were retrieved from the surgical pathology records in the Department of Pathology, Beijing Jishuitan Hospital, Beijing, China. Clinical and radiological data were collected. H&E and immunohistochemistry were used to examine histological and immunophenotypic features and to make the diagnosis and differential diagnosis. The relevant literature was also reviewed. Results: Twenty-eight cases of pediatric myofibroma/myofibromatosis of the soft tissue and bone were respectively collected. The patients' ages ranged from 2 months to 14 years, with a mean age of 7 years. There were 7 females and 21 males. There were 12 cases located in soft tissue, including the finger (n=9), upper arm (n=1) and foot (n=2). There were 14 cases located in the bone of limb, including the femur (n=8), tibia (n=4), clavicle (n=2), fibula (n=2) and radius (n=1). There were 2 cases of myofibromatosis involving multiple bones. Radiology showed lytic lesions in the bone. The proliferation of spindle-shaped myofibroblasts arranged in fascicles with indistinct eosinophilic cytoplasm and bland nuclei, with no pleomorphism and cytological atypia. The characteristic histologic structure was the biphasic nodular growth pattern with cellular and paucicellular regions. The tumors might arrange in a hemangiopericytoma-like pattern. The stroma varied between dense fibrosis and myxoid changes. The reactive new bone formation and inflammatory cell infiltration also existed. Immunohistochemical study showed that the SMA was positive. The surgical resections were performed. One of the patients had tumor recurrence as a result of 11-month follow-up. Conclusions: The pediatric myofibroma/myofibromatosis of the soft tissue and bone is a very rare benign tumor and has a good prognosis. It has a characteristic morphology and its differential diagnosis from other spindle cell tumors could be made with the immunohistochemical analysis.

Myofibroma mimicking peripheral nerve sheath tumour with ulnar nerve compression symptoms.

We report a case of myofibroma encasing the ulnar nerve on the medial aspect of the left arm with motor and sensory deficit secondary to compression. Initially, the tumour appeared to be a benign peripheral nerve sheath tumour based on preoperative imaging, with clinical examination positive for left hand clawing and a positive Wartenberg's and Froment's sign. However, intraoperative dissection demonstrated that the mass did not originate from the ulnar nerve proper, lowering suspicion for a peripheral nerve sheath tumour. Histopathological analysis showed spindle cell neoplasm, consistent with myofibroma. The patient underwent hand occupational therapy subsequently, with improvement of grip strength from 5 lb to 12 lb by 4 months postoperatively and resolution of clawing of the hand postoperatively. We discuss differentiating features for this rare occurrence of solitary adult myofibroma, where the final diagnosis was only made after formal histopathological analysis.

Pediatric Subcutaneous Scalp Mass: A Case Report and Review.

Infantile myofibroma is a unique fibrous tumor encountered in the head and neck. Although the majority of cases are solitary nodules that require only conservative management, awareness of the possibility of multicentric disease is important considering its substantial morbidity. A 3-month-old girl presenting with an enlarging 2.5-cm firm, mobile, nontender subcutaneous scalp mass was evaluated with magnetic resonance imaging and biopsy, revealing a diagnosis of infantile myofibroma. The literature was reviewed for supporting evidence of recommended management in a disease with no official treatment guidelines. Histological, genetic, and imaging characteristics are reviewed. Although biopsy is mandatory, conservative management can be employed for cases without multicentric involvement. Although there are no official guidelines for the evaluation of visceral involvement, skeletal radiograph and abdominal ultrasound are recommended. Infantile myofibroma is a distinct clinical entity with predilection for the head and neck. Its unique immunohistopathology and clinical course should be well understood and should be included in the differential diagnosis of infantile skin and subcutaneous masses.

Solitary cutaneous infantile myofibroma as a hallmark of myofibromatosis: Two cases and review of the literature.

Infantile myofibroma (IM) commonly presents as a benign cutaneous fibrous tumor in infancy. Although the majority of solitary IM regress without any morbidity, some cases have underlying bone or visceral involvement that can lead to both morbidity and mortality. In this report with review of the literature, we present two cases of solitary cutaneous IM with internal involvement and discuss screening cases of solitary IM with full body imaging.

Infantile Myofibroma: A Series of 2 Cases with Special Reference to Cytological Features.

BackgroundInfantile myofibromas (IM) are benign soft tissue lesions of childhood and represent a significant portion of the benign spectrum of fibroblastic-myofibroblastic tumors. Cytological diagnosis of these tumors can be challenging because of overlapping morphology and limited case report descriptions. We describe the cytological features and the cytological differential diagnoses.Case reportWe describe cytological features of two IMs. The main features were the presence of loose clusters and dispersed bland myofibroblasts in varying stages of maturation with traversing blood vessels and myxoid stroma. The cells typically lacked features of atypia, mitoses and significant pleomorphism.ConclusionDiagnosis of IM on the basis of cytology alone can be tricky and definitive diagnosis should be made only after correlating the cytological features with histology. However, bland morphology of differentiating myofibroblasts can aid in cytological diagnosis and help to exclude other malignant spindle cells neoplasms needing preoperative chemotherapy.

Atypical Myofibroblastic Tumor of the Oral Cavity in a Child.

A myofibroma is a relatively rare neoplasm characterized by its spindle cell proliferation. This lesion can present as a unifocal mass (myofibroma) or multifocal growths (myofibromatosis) in the skin, soft tissue, bone, or internal organs. In the oral cavity, the tumor is commonly identified on the tongue, mucosa, lips, and mandible. Myofibroma classically occurs in infants and young children. Its fast-growing nature often mimics a sarcoma; however, it is a benign tumor. The purpose of this article is to report the case of an eight-year-old boy who presented with a localized, painless, nodular mass in the palate and gingiva. Through clinical, radiological, and immunohistochemical evaluation, the diagnosis of an atypical myofibroblastic tumor was made after resection of the mass. With interprofessional team management, the patient's quality of life was improved.

Molecular Alterations in Pediatric Fibroblastic/Myofibroblastic Tumors: An Appraisal of a Next Generation Sequencing Assay in a Retrospective Single Centre Study.

BACKGROUND: Pediatric fibroblastic/myofibroblastic tumors (PFMTs) can be challenging to definitively classify. Large case series or diagnostic updates have not been recently published despite identification of molecular alterations that could improve diagnostic accuracy. Our review of the literature found that over two-thirds of the more than 30 types of PFMTs harbor recurrent molecular alterations. We performed an institutional review of PFMTs to highlight limitations of a predominantly morphological classification, and evaluated the utility of a next-generation sequencing assay to aid diagnosis. METHODS: PFMTs identified over a period of 12 years were reviewed, categorized per the new WHO classification, and tested using the Oncomine Childhood Cancer Research Assay. RESULTS: Eighty-seven specimens from 58 patients were reviewed; 50 were chosen for molecular analysis, 16 (32%) lacking definitive classification. We identified alterations, some novel, in 33% of assayed cases. Expected alterations were identified for most known diagnoses and mutations were identified in 6 of 16 tumors (38%) that were initially unclassified. CONCLUSION: We confirmed a significant subset of PFMTs remain difficult to classify using current criteria, and that a combined DNA/RNA assay can identify alterations in many of these cases, improving diagnostic certainty and suggesting a clinical utility for challenging cases.

Testicular Myofibroma in Children: A Case Report and Review of the Literature.

Testicular tumors are rare in the prepubertal population and often are germ cell tumors. Myofibroma is a rare spindle cell neoplasm composed of myofibroblasts, which are intermediate cells between fibroblasts and smooth muscle cells. Only two prepubertal testicular myofibromas have been previously reported. While cryptorchidism is a risk factor for testicular germ cell tumors, the exact etiology of testicular myofibroma is unknown. We report a case of testicular myofibroma in a six-year-old male with a history of undescended testes, as well as a review of the literature. This case suggests a possible connection between undescended testes and testicular myofibroma.

Inflammatory Myofibroblastic Tumor Presenting as Gross Hematuria in a Pediatric Patient With VACTERL Syndrome Following Bladder Augmentation.

Inflammatory myofibroblastic tumors (IMT) are rare and poorly understood inflammatory neoplasms. Most commonly occurring in the liver and gastrointestinal tract, cases of bladder involvement have been rarely reported. Bladder IMT generally presents with gross hematuria and can be differentiated from other bladder tumors by expression of anaplastic lymphoma kinase. We report the occurrence of an Bladder IMT detected following lower urinary tract reconstruction with bladder augmentation.

Myofibromatosis.

INTRODUCTION: Myofibromatosis is a distinctive mesenchymal disorder occurring predominantly in childhood, which on microscopy shows peripheral light areas of spindle cells and central cellular areas of primitive oval to spindle cells arranged around hemagiopercytomatous vessels. PDFGRB mutations in the familial and multifocal sporadic forms and SRF-RELA fusions in the cellular variants have been identified. The index case is being presented to discuss the clinico-pathological features, differential diagnosis, and management of the lesion. CASE PRESENTATION: An 11-year-old male presented with an infraorbital mass of 3 months duration. The mass was excised and microscopy revealed the morphological features of myofibroma with tram-track SMA immunopositivity. Nodular fasciitis and fibromatosis were the differentials considered. CONCLUSION: The SRF-RELA gene fusion may represent a subset that in the future may be used to differentiate these myofibromas/myopericytomas from the ACTB-GLI fusion myopericytomas, and PDGFRB may be used to perhaps separate out familial myofibromas from other myofibromas.

An unusual case of a solitary cardiac myofibroma causing severe right ventricular outflow tract obstruction in an infant.

Cardiac tumours are relatively uncommon, particularly in children. Myofibroma is an extremely rare variety of cardiac tumour, which nearly always arises in the context of infantile myofibromatosis. Herein, we present a case of a solitary cardiac myofibroma causing right ventricular outflow tract obstruction in a 2-month-old male infant.

Pediatric and Infantile Fibroblastic/Myofibroblastic Tumors in the Molecular Era.

Pediatric fibroblastic/myofibroblastic tumors are rare but include a wide variety of benign to malignant tumors. Given their uncommon frequency, they may present as a diagnostic dilemma. This article is focused on using clinical and pathologic clues in conjunction with the increasingly relevant and available molecular techniques to classify, predict prognosis, and/or guide treatment in these tumors.

Solitary Testicular Myofibroma in a Rabbit.

Myofibromas are mesenchymal tumours of myofibroblastic origin that occur in solitary or multicentric forms. Solitary benign myofibromas mainly occur on the head and neck, especially in the subcutaneous region. They rarely occur in visceral organs in humans, but visceral myofibroma has not been reported in animals. We now report a case of testicular myofibroma in a 6-year-old rabbit in which orchiectomy revealed an enlarged testis with a multinodular surface. The cut surface of the testis showed a thick, homogeneous white-yellow mass surrounding the testicular parenchyma. Histopathologically, the mass was composed of collagen and eosinophilic fascicles of spindle cells that were immunopositive for α-smooth muscle actin but not desmin, S-100 or von Willebrand factor. These features distinguished the myofibroma from other spindle cell tumours. To the best of our knowledge, this is the first report of solitary testicular myofibroma in any animal species.