Isolated infantile myofibroma of the calvarium: Report of a case with a literature review

OBJECTIVE

Infantile myofibromatosis is a rare entity of childhood characterized by benign myofibroblastic tumors in the soft tissues, the bones, and occasionally the viscera. Solitary skeletal lesions are relatively uncommon. Calvarial involvement should be distinguished from more aggressive tumors for appropriate treatment.

METHODS

We reviewed solitary infantile myofibroma of the calvarium and discussed the relevant computed tomography and magnetic resonance imaging findings along with differential diagnosis. A case study of the frontal bone in a 5-month-old girl was also presented.

RESULTS

Fourteen cases were reviewed, including the current case. Of the 13 cases with known sex, eight were male and five female. The mean age was 3.03 with an age range of 0.41-9 years. Nine of the 14 tumors were in the frontal bone. The lesions were intradiploic with tabula interna and/or externa of the calvaria involvement. The mean largest diameter was 22.3 mm. Upon computed tomography, all the lesions were expansile and lytic, and hypoattenuated, isoattenuated or occasionally hyperatenuated. Calcification was not seen. On magnetic resonance imaging, most neoplasms were hypointense on T1-weighted and T2-weighted images. Neoplasms showed hypointense signal on diffusion-weighted imaging and hyperintense on apparent diffusion coefficient, without restricted diffusion in three cases. All lesions were intensely enhanced after gadolinium administration. Treatment was total surgical resection and recurrence was not observed during follow-up.

CONCLUSIONS

Infantile myofibromas are rare, typically intradiploic expansile lytic lesions with tabula interna and/or externa involvement. Distinctive imaging features include the presence of hipointense signals on T2-weighted magnetic resonance images without restricted diffusion on diffusion-weighted imaging. A slow-growing, firm, painless, and nontender mass with supportive imaging findings should raise suspicion of the disease.

Post-surgical thyroid bed myofibroma simulating a recurrent papillary thyroid carcinoma: A case report and review of the literature

RATIONALE

Myofibromas are rare benign spindle cell tumors of the soft tissue, bone, or internal organs that occur at any age. Here, we report a post-surgical thyroid bed myofibroma that mimicked a papillary thyroid carcinoma.

PATIENT CONCERNS

A 56-year-old male presented with a mass in the thyroid surgical bed, detected 3 years post thyroidectomy following papillary carcinoma.

DIAGNOSIS

Thyroid ultrasonography revealed a well-defined, lobulated, hypoechoic, solid nodule, with large rod-like echogenic foci in the thyroid surgical bed. The development of a postoperative suture granuloma was considered. However, ultrasonography performed 12 months later showed a marked increase in the lesion size. Two fine needle aspiration cytology yielded nondiagnostic results.

INTERVENTION

Considering the possibility of local tumor recurrence, surgical resection was performed.

OUTCOME

The diagnosis of a myofibroma was confirmed, and no additional treatment was administered.

LESSONS

It is challenging to differentiate lesions occurring on the thyroid surgical bed after surgery, from recurrent thyroid cancer. A lesion measuring 6 mm, with a degree of punctate echogenicity, suggests tumor recurrence. Moreover, myofibromas are extremely rare. This case highlights that it is advisable to perform a core needle biopsy in cases of nondiagnostic fine needle aspiration results.

A rare case of solitary palatal myofibroma in a young pediatric patient

Myofibroma (MF) is a benign spindle cell neoplasm rarely found in the oral cavity. It is common in males than females (2:1) and mostly seen to develop before 2 years of age with few cases reported in adults. This article reports a rare case of solitary MF of the hard palate in an 8-year-old female child; highlighting the clinical features, histopathology, differential diagnosis while emphasizing the importance of immunohistochemistry in establishing an accurate diagnosis and management of the same. The objective should be to differentiate benign versus malignant spindle cell lesions of smooth muscle, nerve tissue, fibrocytic, and histiocytic origin. Rapid growth of the lesion often raises suspicion of malignancy and may lead to misdiagnosis and inappropriate management.

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.

[Adult myofibroma: a clinicopathological analysis of 15 cases]

Objective: To investigate the clinicopathological features and immunophenotype of adult myofibroma with emphasis on its differential diagnosis. Methods: The clinical, pathologic data and immunohistochemical profiles were analyzed in 15 cases of adult myofibroma diagnosed between 2014 and 2020 in Department of Pathology, Fudan University Shanghai Cancer Center. The literature was reviewed. Results: There were seven males and eight females, with age at presentation ranging from 22 to 74 years (mean 54 years; median 57 years). Tumor occurred principally in the extremities (n=9), less frequently involved the head and neck region (n=3) and trunk (n=2); one case was located in the vertebral canal of C6-7. Fourteen cases were solitary; one case was multifocal. Most patients presented with a slowly growing painless subcutaneous nodule, about 1 to 2 cm in size. One patient with multifocal disease and the patient with spinal lesion complained of intermittent pain. The duration of symptoms ranged from 2 months to 10 years. Microscopically, they were well circumscribed. All cases showed biphasic growth pattern, consisting of relatively well-differentiated eosinophilic nodules alternating with dark-staining primitive-appearing areas. The light-staining hypocellular nodules were composed of myofibroblast-like plump spindle cells within an eosinophilic stroma, which assumed pale blue myxochondroid appearance and hyalinization of varying degree. The dark-staining areas were composed of compact short spindled to ovoid cells with hyperchromatic nuclei and low mitotic activity, frequently showing a distinctive hemangiopericytoma-like architecture. By immunohistochemistry, the myoid spindled cells and the primitive cells stained variably for α-SMA, MSA and calponin, but were consistently negative for desmin and β-catenin. Conclusions: Adult myofibroma tends to occur in the middle to old aged patients with a predilection for the dermis or subcutis of the extremities. It is a benign neoplasm which can be cured by excision in most cases. Familiarity with its distinctive clinicopathological features helps in the distinction from other myofibroblastic neoplasms.

Intraosseous solitary myofibroma of the orbit in an adolescent woman

A 16-year-old woman presented with a painless, progressive, hard swelling in the left inferolateral orbital wall for the past 1 year. There was no diminution of vision or limitation of ocular motility. Imaging revealed an intraosseous, well-defined, expansile, soft tissue lesion in the inferolateral wall of the left orbit. A left anterior orbitotomy with complete surgical excision was performed. Histopathological evaluation of the specimen revealed fascicular pattern of spindle cells with a rich network of slit-like, branching blood vessels. Tumour cells exhibited smooth muscle actin and vimentin positivity but were negative for CD-34 and STAT-6. In absence of any systemic manifestation, a diagnosis of intraosseous solitary orbital myofibroma was made. The case highlights the importance of integrating clinical, radiological and histopathological features in overcoming the diagnostic challenge of differentiating myofibroma from other mesenchymal neoplasms. It also brings forth the importance of complete resection and curettage to prevent recurrence.

Solitary intraosseous myofibroma of the ilium in an adult patient: A case report and literature review

BACKGROUND

Myofibroma is a rare benign tumor typically occurring in the skin and subcutaneous tissues of the head and neck in infants and young children. The incidence of solitary intraosseous and adult myofibroma is extremely low. Although there have been a few reported cases of solitary intraosseous myofibroma in adult patients, most of these cases involved the craniofacial bones.

METHODS

We present the case of a 64-years-old woman presenting with minimal pain of the right buttock and groin.

RESULT

Radiographs and computed tomography showed a huge tumor spreading around the ilium, and non-uniform calcifications were noted inside the tumor. Iliac tumor biopsy was conducted, and intraosseous myofibroma was suspected. We performed surgical resection of the mass, and a final diagnosis of myofibroma with metaplastic bone production was made.

CONCLUSION

We have presented an extremely rare case of solitary intraosseous myofibroma in an adult patient.

[Inflammatory Pulmonary Myofibroblast Tumor Suspected of Pulmonary Metastasis of the Lung Cancer;Report of a Case]

Inflammatory myofibroblastic tumor (IMT) of the lung is a rare disease. The patient underwent the chemoradiotherapy for primary left lung cancer which showed complete responce (CR) by the treatment. A different nodule of 10 mm in diameter was found in the left lung by computed tomography (CT). Positron emission tomography(PET) showed positive detection correspond to the nodule ( SUVmax 4.82). A partial lung resection was carried out, and the tumor was diagnosed as IMT pathologically.

Myopericytoma in an unusual location

Myopericytoma is a soft-tissue tumor of perivascular cells (pericytes). It is slow-growing, usually asymptomatic, and generally benign, although a malignant variant has been described. The etiology is unknown, but it has been associated with local trauma. The most common location is on the distal extremities. Histologically, it is characterized by a well-circumscribed, non-encapsulated proliferation of spindle shaped cells similar to myofibroblasts with oval nuclei and eosinophilic cytoplasm, arranged in perivascular concentric rings. There are few mitoses and no necrosis is reported. The immunohistochemical analysis is positive for smooth muscle actin and negative or weakly positive for desmin. A low Ki-67 proliferation index is typical. Treatment is surgical excision with free margins. Recurrences after adequate excision are uncommon. We describe a 48-year-old woman with a myopericytoma in an unusual location (next to the inner corner of her left eye) who was treated with surgical excision; there has been no recurrence after 5 years of follow up.

Solitary myofibroma of the lumbar vertebra in young adult: A case report with 4-year follow-up of postoperative CT or MRI

BACKGROUND

Solitary myofibroma of the spine is extremely rare, particularly among adults. To the best of our knowledge, only 3 cases affecting lumbar vertebrae have been reported in the English language literature. Of them, only 1 case was an adult case of solitary myofibroma affecting the L1 vertebra.

METHODS

We report a case of solitary myofibroma affecting the L5 vertebra in an 18-year-old man and the postoperative imaging of solitary myofibroma for the first time. Conventional radiographs demonstrated an expansile osteolytic lesion with thinned cortex and marginal sclerosis. Computed tomography (CT) showed a purely osteolytic expansile lesion with partial disappearance of thinned cortex. MRI of the lesion revealed an isointense signal on T1-weighted images, an inhomogeneous slightly hyperintense signal on T2-weighed images, and homogeneous avid enhancement with gadolinium.

RESULTS

Surgical excision was performed and the lesion was diagnosed as solitary myofibroma on pathological examination. One-year follow-up postoperative CT demonstrated decreased size of the osteolytic lesion with sclerotic change. Four-year follow-up postoperative MRI revealed complete resolution of the lesion replaced by normal fatty marrow.

CONCLUSION

If a benign-looking expansile osteolytic lesion reveals a homogeneously isointense signal on T1-weighted image, inhomogeneous slightly hyperintense signal on T2-weighted image, and homogeneous avid enhancement with gadolinium, solitary myofibroma should be considered in the differential diagnosis of spine bone tumors. It can be resolved completely.

Renal myopericytoma: a clinicopathologic study of six cases and review of the literature

To evaluate the morphologic features, immunohistochemical profiles, and biological behavior of renal myopericytoma. Six cases of renal myopericytoma are retrospectively retrieved and analyzed by H&E and immunohistochemical staining. Clinically, patient's age ranged from 33 to 70 years (median, 56 years). Male to female ratio was 5:1. Five of the six patients were asymptomatic of the urinary tract, the remained one presented with abdomen pain. Grossly, all six tumors were solitary masses with sizes ranging from 1.8 to 7.3 cm of maximum diameter (mean, 4.4 cm). Five tumors were described as well-circumscribed, and 1 case was showed as ill-defined. Histologically, in all cases, numerous thin-walled vessels and a perivascular arrangement of ovoid, spindled or round myoid tumor cells were seen. However, a broad morphologic spectrum ranging from fibroma-like (3 cases), glomangiopericytoma-like (3 cases), angioleiomyoma-like (2 cases), glomoid- like (2 cases), and myofibroma-like (2 cases) components were observed. In addition, 1 neoplasm with immature cellular features and another infiltrating myopericytoma were found. A coexisting papillary adenoma was detected in 1 case. Nuclear atypia was seen in 2 cases. Immunohistochemically, SMA, caldesmon, and MSA were positive in all 6 cases, whereas CD34 and desmin was partial positive in 1 case, respectively. Ki67 index was aproximately 5% in 1 case but less than 2% in the others. All patients are free of disease by follow-up ranging from 14 to 66 months (mean, 38.7 months).

Laryngeal inflammatory myofibroblastic tumor

Inflammatory myofibroblastic tumor seldom involves the larynx, as only about 50 to 60 cases have been described in the literature. Even though these tumors are often not aggressive, they have the potential for invasion and local recurrence. We describe the case of a 27-year-old man who was admitted to an emergency department with signs of upper airway obstruction secondary to an obstructive mass. Histology identified the mass as an inflammatory myofibroblastic tumor of the subglottis. The patient underwent an emergency tracheotomy followed by a partial laryngectomy. During 14 months of follow-up, he remained free of active disease.

Solitary myofibroma of the oropharynx causing airway obstruction in an adult

Myofibromas are benign neoplasms believed to be the most common fibrous proliferation of childhood. We present an unusual case of a 44-year-old woman who developed acute airway obstruction from a myofibroma in the oropharynx and accordingly required emergent tracheotomy tube placement. Serial laser excisions to adequately remove the entire lesion while maintaining pharyngeal structure and function were performed, and the patient was successfully decannulated. To date she has remained free of signs and symptoms of recurrence. Although rare in adults, solitary myofibromas should be considered in the differential diagnosis of any subcutaneous or submucosal head and neck lesion. Moreover, clinicians treating adult and pediatric patients with known solitary or multicentric forms of myofibroma should be aware of its potential for airway obstruction. Patients found to have a pharyngeal myofibroma should be managed with airway stabilization, surgical excision with preservation of speech and swallow function, and close postoperative monitoring for recurrence.

Solitary myofibroma of the mandible: an immunohistochemical and ultrastructural study with a review of the literature

A solitary myofibroma (MF) is an unusual spindle cell neoplasm that usually arises in the soft tissue, skin, or bone of the head and neck region in infancy. We report an extremely rare case of MF of the mandible in an 18-year-old Japanese woman together with the conventional histologic, immunohistochemical, and electron microscopic findings. The tumor was well circumscribed and composed of fibroblast-like or myofibroblast-like spindle cells. On immunohistochemical evaluation the tumor cells were positive for vimentin, α-smooth muscle actin, HHF-35, and calponin, but negative for neurogenic antigens and markers for vascular endothelial cells. The Ki-67 labeling index was 10 % and the p53 labeling index was 10 %. Ultrastructural examination revealed smooth muscle cell differentiation. The patient was treated by surgical resection and underwent follow-up without any signs of recurrence. MF presents a wide range of differential diagnosis, including benign and malignant neoplasms. Therefore, accurate diagnosis may avoid an unnecessarily aggressive therapy.

Submandibular myofibroma: a case report

PURPOSE

Myofibroma is a rare benign spindle cell neoplasm, and the aim of the present study was to carry out a literature review and present a clinical case of a patient with a myofibroma in the submandibular region and its management.

CONCLUSIONS

Diagnosis of myofibroma can be reached by a histopathologic and immunohistochemical analysis and surgical excision is the treatment of choice.

Pediatric solitary intraosseous infantile myofibroma of the mandible

Myofibroma is a rare benign tumor of myofibroblastic origin that presents as solitary or multiple, and as an intraosseous and/or soft tissue lesion. It most commonly occurs in infants and children, although adult myofibromas have also been reported. Solitary central infantile myofibroma of the jaws is very rare and should be considered in the differential diagnosis of central jaw lesions involving the mandible in children. Its etiology is unknown. The purpose of this manuscript is to report a case of solitary intraosseous infantile myofibroma of the mandible wherein trauma may have been a contributory factor to the development of the tumor. The importance of immunohistochemistry in diagnosing this entity has also been emphasized. Resection should be preferred over enucleation when the lesion infiltrates the surrounding bone.

A case of congenital myofibroma of the orbit presenting at birth

PURPOSE

The purpose of this report is to highlight a rare cause of congenital proptosis.

METHODS

This is a case report.

RESULTS

We present a case of a baby girl born with a large myofibroma in the right retrobulbar space. This case is unusual because it presented from birth and was in a critical location. A prenatal ultrasound performed two days prior to birth did not reveal this mass to the technician or obstetrician. At birth, the tumor induced severe proptosis, with the eyelids unable to close around the globe. Deterioration of the ocular surface secondary to exposure was evident immediately after birth. One week after birth, the mass was excised by the Oculoplastics service in conjunction with a Neurosurgical team using a transcranial approach. The tumor was diagnosed by histopathology and immunologic staining as a myofibroma, a rare condition.

CONCLUSIONS

Orbital myofibroma is a rare cause of congenital proptosis presenting at birth.

Myofibroma of the mandible: a case report

This report describes the case of a male aged 28 years who presented with a chief complaint of discomfort and swelling in the mandibular right molar area. An incisional biopsy was performed with a preliminary differential diagnosis of periodontal abscess, fibrotic lesion, or odontogenic tumor. Subsequent excision of the lesion was performed and histologic analysis confirmed the diagnosis of myofibroma.

Isolated infantile myofibromatosis of the upper eyelid: uncommon localization and long-term results after surgical management

Myofibroma, the most common juvenile fibrous disorder in infancy, usually manifests as a solitary soft tissue tumor and less commonly as simultaneous multiple tumors in both soft tissue and bones. Infantile myofibromatosis is well described in the head and neck, but cutaneous lesions rarely occur in the periorbit and orbit, where fast growth and bone damage can mimic malignant tumors. We describe a case of a solitary periorbital myofibroma in a newborn. Treatment consisted of partial excision of the tumor. Histologic and immunohistochemistry analyses provided the diagnosis of infantile myofibromatosis. The patient remains disease-free at 10 years of age, but with some visual impairment. Infantile myofibromatosis is an uncommon tumor with exceptional periorbital involvement. Differential diagnosis can be difficult when it is solely based on histologic assessment. Immunohistochemistry evaluation demonstrating cytoplasmic actin filaments in neoplastic spindle cells confirms the diagnosis. As soon as the diagnosis is made, chest and abdominal imaging must be performed to evaluate the overall prognosis and direct treatment. The treatment of choice is early conservative surgery to minimize functional and/or esthetic damage. Complete tumor excision is not always possible. Lengthy ophthalmologic monitoring is required to detect the onset of amblyopia.

Myofibroma of the oral mucosa: a case report

OBJECTIVE

To report a case of coexisting irritation fibroma and myofibroma in oral mucosa.

CLINICAL PRESENTATION AND INTERVENTION

One case with two painless, nodular masses, adjacent to each other in the buccal mucosa, was clinically examined with a provisional diagnosis of irritation fibroma, salivary gland tumors, neurofibroma and schwannoma. Histological examination of the smaller swelling showed features of irritation fibroma, while the features of the other mass were compatible with myofibroma or leiomyoma. Additional immunohistochemical examination established the diagnosis of myofibroma.

CONCLUSION

This was a case of a myofibroma that was clinically similar to an adjacent irritation fibroma, which highlights the possibility of misdiagnosis of a myofibroblastic tumor and underlines the importance of histologic examination together with immunohistochemical and/or histochemical analysis if necessary to establish the accurate diagnosis.

Dermatomyofibromas presenting in pediatric patients: clinicopathologic characteristics and differential diagnosis

Dermatomyofibroma represents a rare benign fibroblastic/ myofibroblastic cutaneous tumor that mostly occurs in young adult women. It has been seldom reported in pediatric patients. In this analysis, the clinical, histopathological and immunohistochemical findings of 12 dermatomyofibromas occurring in patients up to 16 years of age are compared with those reported in adults. Six patients were male and six were female. Nine lesions were located on the neck, two on the back and one involved the chest. The usual presentation was as an asymptomatic plaque composed of bland spindled cells arranged in dermal fascicles that were oriented parallel to the epidermis. Immunohistochemically, the lesional cells expressed calponin in 11 cases, smooth muscle actin in six and muscle-specific actin in three. In contrast to prior reports from adults, dermatomyofibromas in pediatric patients do not show a female predilection. In addition, they are mostly located on the neck (56%), while in adults the most frequent location is the shoulder (35%). Dermatomyofibromas seem to stabilize after an initial period of enlargement. Punch biopsy and clinical follow up could be an alternative approach to the surgical excision in some cases of dermatomyofibroma, particularly in instances in which surgery might inflict cosmetic defects.

[Congenital solitary infantile myofibroma: report of two cases]

The infantile myofibromatosis is a rare pathology usually affecting children under 2 years. More than half are congenital, located in head and neck in a 30% of the cases. Myofibroma is a benign mesenchymal tumor that appear an isolated lesion or multiple, with or without visceral involvement. Case 1: A newborn girl that presents lump in scalp suspected of encefalocele. Ultrasound and RM: solid and heterogeneous mass 4 x 2 cm with increased peripheral vascularisation. Case 2: A 7-month-old baby boy with lump in right occipital zone detected at 4 months. Ultrasound and RM: injury 1 x 1.5 cm in head esplenio muscle suggestive of hemangioma.

RESULTS

After surgical total resection, the histological study and immunohistochemical identified the lesion as myofibroma. The evaluation of disease dissemination was normal and the recovery of the patients was favorable. The differential diagnosis of myofibroma must be carried out with other mesenchymal tumors and with non neoplastic injuries characteristics of the region affects. The visceral location and multiple forms worsen the prognosis, so is important do an exhaustive study. Treatment is conservative surgery, but if there is no risk to the child, the possibility of spontaneous regression makes the abstention therapeutic a correct alternative.

Dermatomyofibroma mimicking granuloma annulare

We report the case of a 9-year-old girl with a lesion on the posterior aspect of the neck, which was clinically compatible with granuloma annulare. An incisional biopsy was performed and the result of the biopsy was consistent with a fibrohistiocytic proliferation. After the total excision of the lesion, the definitive diagnosis of dermatomyofibroma was determined. Dermatomyofibroma is a benign and rare proliferation of myofibroblasts of the skin. Dermatomyofibroma is a solitary and slowly growing tumor. It is more common in adolescents and young adults, with a female preponderance. Dermatomyofibroma presents clinically as a papule or nodule. It may be slightly hyperpigmented. It is usually located on the upper trunk, axilla, upper arm, or neck. The treatment of choice is complete excision and the prognosis is excellent.

[Myofibroma of the mandibule: a case report]

INTRODUCTION

Myofibromatosis is a rare tumor. Two forms are described, solitary and multicentric, the solitary type is more common and is localized mainly on the head and the neck, mandible involvement is rare. The recent observation of a patient with a myofibrome of the mandible has given the opportunity to conduct an analysis and review of the literature of this disease rarely encountered.

MATERIALS AND METHODS

We report a case illustrating solitary myofibroma of the mandible in a 16 year old man.

RESULTS

The histological diagnosis was done on the identification of the spindle-shaped tumoral proliferation and the positive expression of the anti-vimentine, anti-smooth, muscle actin anti desmin. The treatment was surgical.

DISCUSSION

myofibromatosis often presents as a painless, well-circumscribed, solid nodule. Imagery is very useful to assess lesion extension and for the therapeutic followup. The diagnosis is made on anatomopathological findings and immunohistochemical assessment. The treatment of the solitary myofibromatosis is primarily surgical and its prognosis is excellent contrary to the multicentric form.

Myofibroma of the external auditory canal: report of an adult case

Myofibroma of the external auditory canal: report of an adult case.

OBJECTIVE

Myofibroma is a benign fibrous proliferative disease generally reported to occur in neonates and children. Similar lesions have been reported in adults, but solitary tumours affecting the external auditory canal are extremely rare. Only one such case has been reported in the literature.

CASE REPORT

The case of solitary myofibroma occurring in the external auditory canal of a 42-year-old woman is presented. The diagnosis of myofibromatosis was made on the basis of its histological appearance and corroborated by immunohistochemical staining.

CONCLUSIONS

Clinicians and pathologists must be aware that myofibromatosis may occur in adults at extremely rare locations. Myofibroma should be included in the differential diagnosis of fibrous lesions in the external auditory canal.

Myofibroma of the mandible

This article is reporting a case of myofibroma involving the mandible of a 12-year-old boy. The patient did not have any swelling nor any redness but of partial mental nerve hypoesthesia. A panoramic radiograph demonstrated a globe like radiolucent lesion in the left angle of the mandible that was an increased uptake spot by FDG-PET. Incisional biopsies indicated myofibroma, therefore the tumor was totally resected under general anesthesia. After surgery there was no complication except for a change for the worse of unilateral mental nerve hypoesthesia. At 29 months postoperative, no evidence of recurrence could be found.

[Congenital myofibroma. A true hemangiopericytoma. A neonatal case with immunohistochemical and ultrastructural studies]

We report the case of a male newborn infant with a pedunculated dermic tumor, located in the right malar region; who underwent a complete surgical resection of the tumor and had a satisfactory postoperative evolution. The histopathologic findings disclosed a subcutaneous tumor with a nodular aspect and a subendothelial intravascular growth, constituted by a dual population of small cells and spindle-shaped cells, distributed in a biphasic pattern. All tumor cells showed a strong pericellular reaction for PAS. The immunohistochemical studies revealed: diffuse cytoplasmic positivity for CD34 and Vimentin in all tumor cells, and only spindle-shaped tumor cells and less differentiated isolated neoplastic cells, presented cytoplasmic positivity for the smooth muscle alpha-actin. The electronic microscopy demonstrated a layer of basal membrane and in the citoplasm, numerous intermediate filaments with focal condensations. Based on all these findings, we conclude that this is a myofibroma, a "true hemangiopericytoma" with myofibroblastic differentiation. For this reason, we propose the term myofibropericytoma, in order to highlight its pericytic origin and its myofibroblastic differentiation. We emphasize the need to recognize this entity, in view of its low frequency and the possibility of a diagnostic mistake with other soft tissues tumors that display haemangiopericytoma-like features.

Plexiform angiomyxoid myofibroblastic tumor of the stomach

We report 2 cases of plexiform angiomyxoid myofibroblastic tumor of the stomach, a tumor entity that has not been described previously. The patients were a 50-year-old man (case 1) and a 68-year-old man (case 2). In case 1, the patient presented with acute abdominal pain. The tumor in case 2 was incidentally found at laparoscopic cholecystectomy. Grossly, the tumors were 4.0 cm (case 1) and 4.5 cm (case 2) in their greatest dimension, and they were recognized as submucosal tumors. The tumor caused gastric perforation in case 1. Histologically, the tumors extended from the serosa to the submucosa of the gastric wall, showing a plexiform growth pattern. Bland spindle tumor cells were observed, and they were separated by abundant intercellular myxoid matrix. The stroma was rich in small vessels. Immunohistochemically, the tumor cells were positive for alpha-smooth muscle actin and muscle actin, and negative for KIT, CD34, and S-100 protein. Electron microscopic findings were consistent with the myofibroblastic nature of the tumor cells. No mutations were found in the c-kit and platelet-derived growth factor receptor alpha genes. Although clinical follow-up data were insufficient, the histologic appearances suggested the benign nature of the tumors. However, the tumor in case 1 caused gastric perforation and necessitated an emergency operation.

A case of an inflammatory myofibroblastic tumor of the mastoid presenting with chronic suppurative otitis media

Inflammatory myofibroblastic tumors, also known as inflammatory pseudotumors, include a diverse group of lesions characterized by inflammatory cell infiltration and variable fibrotic responses. Their occurrence in the temporal bone is unusual. We present a case of an inflammatory myofibroblastic tumor of the mastoid bone in a 55-year-old female who complained of repeated otorrhea and a hearing impairment. On an otoscopic exam, her tympanic membrane was perforated. The computed tomographic imaging revealed a soft-tissue density-filled middle ear and mastoid with sclerotic bony change. The initial clinical diagnosis was chronic suppurative otitis media and mastoiditis, and the patient underwent a canal-wall down tympanomastoidectomy through a retroauricular approach. A histopathologic examination showed the presence of myofibroblastic spindle cells with mixed inflammatory infiltrates, and the pathologic diagnosis was inflammatory myofibroblastic tumor.

Central (intraosseous) myofibroma of the mandible: clinical, radiologic, and histopathologic features of a rare lesion

OBJECTIVE

Myofibroma frequently manifests as a solitary soft tissue tumor and less as simultaneous multiple tumors in both soft tissues and bones. The present study evaluated clinical, radiological, and histopathologic features of myofibroma of the jaws.

STUDY DESIGN

Nineteen cases from the literature and 4 new cases were analyzed.

RESULTS

At initial diagnosis, age ranged from birth to 34 years (mean 7.2 years, median 6 years). Male/female ratio was 2.3:1. Myofibromas were radiolucent solitary lesions located solely in the mandible: 70% unilocular, 30% multilocular; 67% with well-defined borders. Conservative treatment was performed on 75% of the patients; 25% underwent partial jaw resection. Where information was provided, no lesion recurred during 6-month to 17-year follow-up.

CONCLUSION

Although rare, myofibroma of the mandible should be considered in the differential diagnosis of radiolucent lesions (particularly unilocular), especially in children. Treatment of choice is conservative surgery to minimize potential functional and/or esthetic damage.

Fetal neck myofibroma

Magnetic resonance imaging (MRI), as an adjunct to ultrasonography, has become a promising tool in prenatal diagnosis and therapy. In this report, the authors described a case of giant solid mass arising in the fetal neck region diagnosed by prenatal sonographic examination at the gestational age of 33 weeks'. MRI was used to confirm the diagnosis, and to assist fetal airway assessment. Due to the concern of fetal airway compromise, the ex utero intrapartum treatment (EXIT) was strategically planned with help from specialists in the according fields. This allowed the authors to secure the fetal airway before fetomaternal circulation was disconnected. It was performed successfully through Cesarean section at the time of birth. Histopathology revealed infantile myofibroma, which is a rare form of such a tumor arising on the fetal head and neck region diagnosed prenatally.

Solitary intraosseous orbital myofibroma in four cases

PURPOSE

To report four pediatric cases of a bone-destructive orbital tumor that proved to be a benign solitary intraosseous myofibroma.

METHODS

Four children, aged 1, 7, 11, and 72 months, developed eyelid fullness or slight proptosis. A solitary intraosseous mass was detected in the inferior (n = 2), superotemporal (n = 1), and supranasal (n = 1) orbital walls. On CT, the mass showed bone destruction. On MRI, the mass appeared circumscribed within a shell of normal surrounding bone and with features of isointensity on T1-weighted images, intense homogeneous gadolinium enhancement, and midrange signal on T2-weighted images. Complete surgical excision of the mass in each case was performed.

RESULTS

On histopathologic examination, the tumors were characterized by whorls and bands of plump myoid cells with eosinophilic cytoplasm consistent with myofibroblasts, sometimes associated with a hemangiopericytoma-like vascular pattern. The diagnosis was also supported by immunohistochemical studies showing positive immunoreactivity for vimentin and smooth muscle actin. None of the patients have shown recurrence in follow-up ranging from 6 months to 3 years.

CONCLUSIONS

Myofibroma is a benign tumor that can occur in the orbital bony wall of children. It can manifest as a bone destructive mass and can simulate a malignant process.

Solitary orbital infantile myofibroma: a case report and review of the literature

Infantile myofibromatosis is a benign condition involving the skin, viscera, or bone that presents rarely in the orbit where rapid growth and bony destruction can mimic malignant tumors. Lesions can be solitary or scattered throughout the body. Growth in viscera such as the lungs can lead to death. Herein, we present a case of a solitary orbital myofibroma in a young child.

Solitary infantile myofibroma of the orbital bone

Infantile myofibroma of the orbit is an extremely rare condition. Only a few instances of this condition have ever been reported. A 3-year-old boy visited our clinic with lateral lower eyelid swelling and a palpable mass in the left eye, which had apparently persisted for 2 months. A computed tomography scan revealed a well-circumscribed mass in the inferolateral orbital portion of the zygomatic bone, coupled with erosion of bone and orbital extension with reactive hyperostosis. Immunohistochemical stains proved positive for smooth muscle actin, supporting the diagnosis of solitary infantile myofibroma of the orbital bone (zygoma). Although rarely found in the orbit, solitary infantile myofibroma can display more aggressive or malignant neoplasm. Immunohistochemistry is integral to the differential diagnosis and a systemic evaluation for multicentric myofibroma is essential.

Solitary testicular myofibroma: a case report and review of the literature

Myofibromas are benign mesenchymal neoplasms of myofibroblastic origin. Most present as solitary lesions at any age, but the presentation of multiple lesions in newborns and infants is known as infantile myofibromatosis. Multicentric lesions commonly involve soft tissues and bone and may involve internal organs, where they are associated with an unfavorable prognosis. Solitary lesions involving the viscera are rare. We report a case of a 3-month-old male infant with a left testicular mass detected during an evaluation for suspected torsion. The patient underwent orchiectomy, revealing a nodular mass with grossly evident foci of necrosis. Histologically, the lesion exhibited small fascicles of plump eosinophilic, smooth muscle actin-positive spindle cells, alternating with larger areas of primitive cells with vesicular nuclei and scant cytoplasm arranged around a hemangiopericytoma-like vasculature. To our knowledge, this is the first report of a myofibroma localized within the testis.

Inflammatory myofibroblastic tumor associated with renal cell carcinoma

A 46-year-old man was referred for evaluation of a 13-cm renal mass. Right radical nephrectomy was performed. Pathologic evaluation revealed inflammatory myofibroblastic tumor (IMT) and renal cell carcinoma. To our knowledge, only 28 cases of IMT associated with the kidney have been reported in published studies. This is the first reported case of IMT associated with malignancy in the urogenital tract. Some investigators have suggested that biopsy-proven IMT can be managed conservatively, but the findings of this report have demonstrated the need for radical nephrectomy in this patient population to rule out associated malignancy.

Urachal inflammatory myofibroblastic tumor with ALK gene rearrangement: a study of urachal remnants

OBJECTIVES

Abnormalities of the urachus are rare among children and include a patent tract and cyst formation. These structures can also be affected by infection and abscess development. They are usually diagnosed during infancy and treated by surgical resection. Involvement of this remnant by either benign or malignant tumors is very infrequent. A few cases of mesenchymal tumors, such as desmoid tumor and leiomyoma, involving the urachus have been described in published reports.

METHODS

We studied an inflammatory myofibroblastic tumor arising from the urachus in a 10-year-old boy. In addition, we reviewed 101 cases of urachal remnants retrieved from the surgical pathology and autopsy files in the Department of Pathology at the Children's Hospital Boston diagnosed in the past 82 years.

RESULTS

The urachal inflammatory myofibroblastic tumor showed anaplastic lymphoma kinase (ALK) rearrangement by immunohistochemistry and fluorescence in situ hybridization techniques. No other neoplasms were diagnosed in the analyzed population.

CONCLUSIONS

We describe an example of inflammatory myofibroblastic tumor involving the urachus. Involvement of the urachus by tumors is rare, but these should be considered in the differential diagnosis of urachal lesions.