Solitary myofibroma in adults: clinicopathological analysis of a series

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.

Adult-Onset Multifocal Cutaneous Myofibromas: A Case Report of a Rare Entity

Myofibromas are observed in both infantile and adult presentations, with key differences in the number and severity of lesions between these two groups. Infantile presentations encompass both indolent, isolated cutaneous lesions, as well as aggressive, multicentric presentations with visceral involvement. Adult myofibromas appear to be characterized by a single isolated cutaneous lesion, generally asymptomatic and following a benign clinical course. The occurrence of adult multifocal myofibromas has not yet been described in the literature. Here, we report a case of a 57-year-old female who presented with two minimally symptomatic soft tissue lesions on her right leg, with the pathologic findings of each lesion consistent with a cutaneous myofibroma. This case report describes a rare presentation of adult-onset multifocal cutaneous myofibromas.

Gene fusions in superficial mesenchymal neoplasms: Emerging entities and useful diagnostic adjuncts

Cutaneous mesenchymal neoplasms are diagnostically challenging because of their overlapping morphology, and, often, the limited tissue in skin biopsy specimens. Molecular and cytogenetic techniques have identified characteristic gene fusions in many of these tumor types, findings that have expanded our understanding of disease pathogenesis and motivated development of useful ancillary diagnostic tools. Here, we provide an update of new findings in tumor types that can occur in the skin and superficial subcutis, including dermatofibrosarcoma protuberans, benign fibrous histiocytoma, epithelioid fibrous histiocytoma, angiomatoid fibrous histiocytoma, glomus tumor, myopericytoma/myofibroma, non-neural granular cell tumor, CIC-rearranged sarcoma, hybrid schwannoma/perineurioma, and clear cell sarcoma. We also discuss recently described and emerging tumor types that can occur in superficial locations and that harbor gene fusions, including nested glomoid neoplasm with GLI1 alterations, clear cell tumor with melanocytic differentiation and ACTIN::MITF translocation, melanocytic tumor with CRTC1::TRIM11 fusion, EWSR1::SMAD3-rearranged fibroblastic tumor, PLAG1-rearranged fibroblastic tumor, and superficial ALK-rearranged myxoid spindle cell neoplasm. When possible, we discuss how fusion events mediate the pathogenesis of these tumor types, and we also discuss the related diagnostic and therapeutic implications of these events.

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 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.

Epibulbar solitary myofibroma in an elderly patient: a case report

A 93-year-old male patient presented with abrupt expansion of an old epibulbar mass at the temporal area of the left eye. He had a medical history of previously treated laryngeal cancer with surgery and radiotherapy. The tumor, despite being firmly attached to the underlying sclera, was excised completely and histopathological examinations revealed a solitary myofibroma. The patient had a 4-month uneventful follow-up with excellent wound healing. Solitary myofibroma may be a differential diagnosis for epibulbar masses in elderly patients.

Solitary adult orbital myofibroma: Report of a case and review of the literature

Purpose

Myofibromas are benign soft tissue tumors commonly encountered in infancy and childhood. Developing usually within the first two years of life, they can be multicentric and involve deep visceral organs.

Observations

We present the rare occurrence of a solitary orbital myofibroma in an adult patient. The clinical, histopathologic and immunohistochemical findings of the tumor are documented.

Conclusions

A comprehensive review of pediatric and adult orbital and periocular involvement by myofibroma is presented. Its characteristic pathologic and molecular findings are reviewed.

Importance

Myofibromas are uncommon but important tumors that can occur in the head and neck region, including the orbit. Seen more often in children, they can rarely be encountered in adult patients. Diagnosis is possible with a panel of immunostains and molecular analysis can be further confirmatory.

Solitary intramuscular myofibroma in an adult: Case report and MR imaging findings

Myofibroma is a benign, soft tissue neoplasm that predominantly affects infants and young children. Most occur in the skin or subcutaneous tissues, with a predilection for the head and neck regions. We describe the magnetic resonance (MR) imaging and histophathologic findings of a rare case of intramuscular myofibroma of the right deltoid in a healthy 30-year-old male. MR imaging revealed a well-circumscribed intramuscular mass, with isointense signal on T1-weighted images, hyperintense signal on T2-weighed images, and a "target-sign" with peripheral rim enhancement after gadolinium administration. The lesion was surgically excised with no complications, and the histopathologic analysis revealed the typical morphologic and histochemical markers of a myofibroma. We conclude that, although rare, myofibroma can be considered in the differential diagnosis of adults with lesions the above signal characteristics.

Infantile Myofibroma Presenting as a Large Ulcerative Nodule in a Newborn

The differential diagnosis of a congenital cutaneous vascular-appearing mass in a newborn is broad and includes both benign and malignant tumors. We report the case of a newborn who presented with an erythematous exophytic skin nodule on the right upper leg. Excision was performed due to ulceration, concern for bleeding, and for diagnosis. Pathology revealed the mass to be an infantile myofibroma. This case highlights the importance of considering a broad differential diagnosis in a newborn with a cutaneous mass. While history, physical exam, and imaging can help diagnose some cases, a biopsy or excision is often needed to distinguish benign lesions from more concerning lesions.

Spontaneous Radial Nerve Palsy due to an Unrecognized Myofibroma: A Case Report

CASE

A 33-year-old woman presented with a six-month history of spontaneous radial nerve palsy and no identified lesion on imaging. She underwent operative exploration where an hourglass deformity was seen and resected. Pathology returned as a rare tumor, a myofibroma. The patient regained full radial nerve function.

CONCLUSIONS

A trial of observation is often indicated in the cases of isolated nerve palsy where anatomic lesions have been eliminated. This case highlights that imaging studies can miss a tumor involving nerve and that painless, spontaneous nerve palsy may be a time where early surgical intervention offers a better chance of recovery.

Nonepithelial Tumors and Tumor-like Lesions of the Skin and Subcutis in Children

This overview of mesenchymal tumors presenting in the skin and/or subcutis in children brings together the range of neoplasms and hamartomas which are seen in this age-group. It is not surprising from the perspective of the pediatric or general surgical pathologist that vascular anomalies, including true neoplasms and vascular malformations, are the common phenotypic category. Since there is considerable morphologic overlap among these lesions, clinicopathologic correlation may be more important than for many of the other mesenchymal tumors. The skin and subcutis are the most common sites of clinical presentation for the infantile myofibroma which is the most common of fibrous mesenchymal tumors in children. Several of the other mesenchymal tumors are more common adults-like dermatofibrosarcoma protuberans, but nonetheless have an important presence in children, even as a congenital neoplasm. A lipomatous tumor in a young child should be considered as a possible manifestation of an overgrowth syndrome.

Spontaneous involution (regression) of a solitary cutaneous myofibroma in an adult patient

Myofibromas are unusual benign tumors most commonly seen in infant children. Clinical involution of the tumor often occurs within the first few years of life. Solitary cutaneous myofibroma is the synonymous adult counterpart of infantile myofibromatosis. Although solitary myofibromas have been reported in patients of all ages, only the infantile variant is believed to regress spontaneously. There are only a few case reports of adolescent and young adult patients with regressing solitary lesions that have been described in the literature to date. We report a 71-year-old male with spontaneous regression of solitary cutaneous myofibroma. The residual lesion was excised and to date has not recurred. This report describes the historical, clinical and histopathological features of adult myofibromas and a novel manifestation that may guide future clinical considerations when approaching solitary tumors with regressive features.

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.

Six Cases of Myofibroma--The Adult Counterpart of Infantile Myofibromatosis: Case Report

The adult counterpart of infantile myofibromatosis is rare and is known as myofibroma. Cases are rare, and previous ones have been reported as isolated case reports; hence, there has been no consensus regarding the clinical presentation, surgical reconstruction, histological features, and recurrence of hand myofibromas. Over a 10-year period, the senior author treated 6 patients. We review our cases as well as 6 previously reported cases. The presentation is usually a single hand mass in a young adult. The tumor may arise from the lower dermis or from deeper fibrous structures of the hand including the palmar fascia. Tumors that arise from the dermis are best treated by skin excision to ensure complete excision. Histologically, the tumor is composed of highly cellular myofibroblast proliferation and is strongly positive to smooth muscle actin immune stain. The recurrence rate after excision is low.

Nodular Fasciitis Involving the Cornea: A Case Report and Review of the Literature

PURPOSE

To report a case of nodular fasciitis involving the cornea and to review the literature of all published cases of epibulbar nodular fasciitis.

METHODS

A 38-year-old man presented with a progressively enlarging flesh-colored nodule adherent to the central cornea of his right eye.

RESULTS

The nodule was surgically excised. Pathologic examination and immunohistochemistry were consistent with nodular fasciitis, a pseudoneoplastic spindle cell tumor.

CONCLUSIONS

A review of the literature confirms this is the first reported case of nodular fasciitis involving the cornea since the original series by Zimmerman et al describing nodular fasciitis of the eye. Surgical excision alone is likely the most appropriate treatment option.

Intravascular myopericytoma in the heel: case report and literature review

Intravascular myopericytoma (IVMP), regarded as a variant of myopericytoma, is a rare tumor. Very few cases have been described, none in the foot.The first case of IVMP located in the heel of the foot is described in this article. A literature review is reported of all cases of IVMP published in the English literature.A 48-year-old man possessed an IVMP on the heel of the right foot. The physical examination and histopathological and ultrasound studies are described. The literature review yielded 5 cases of IVMP, 2 of which were in the thigh and 1 each in the oral mucosa, the periorbital region, and the leg.The possibility that these lesions may be malignant suggests that the histopathological study of vascular tumors should include immunohistochemical tests.

Solitary intraosseous myofibroma of the tibia in an adult patient: A case report

Myofibromas are mesenchymal tumors showing myofibroblastic differentiation and found most frequently in the head and neck region. While several cases of myofibromas have been reported in adults, they have not been described in long bones of the appendicular skeleton. We describe an otherwise healthy young woman who presented with a progressive incapacitating pain in her right shin. Imaging studies revealed a well-circumscribed osteolytic lesion with slight marginal sclerosis confined to the proximal tibia metaphysis, without a soft tissue component. Surgical intervention was performed and histological examination identified a myofibroma.

This case represents an extremely rare occurrence of an intraosseous myofibroma involving a long bone in an adult patient. Although solitary myofibroma is a rare lesion in the skeletal bones of adults we believe it should be included in the differential diagnosis of a solitary lytic mass in bone, especially if it is associated with pain.

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.

Solitary infantile myofibromatosis in the bones of the upper extremities: Two rare cases and a review of the literature

Infantile myofibromatosis (IM) is the most common fibrous tumor of infancy. IM may arise in a solitary or multicentric form, with similar histopathological findings, however, the clinical features and prognoses may vary. The solitary form tends to occur predominantly in males and is typically observed in the dermis, subcutis or deep soft tissues. The reported incidence of solitary osseous myofibromatosis is rare. Furthermore, the majority of solitary IM cases of the bone occur in the craniofacial bones, while the occurrence of solitary osseous myofibromatosis on the extremities has been sporadically reported. The present study describes two cases of solitary IM involving the bones of the upper extremities in females who were over two years old. The cases show unusual symptom presentation and the tumor origin is in a rarely observed location. The study discusses the clinical, radiological and pathological features, in addition to the previously described etiology, prognosis and treatment options for this condition.

Pleomorphic adenoma of the salivary glands with intravascular tumor deposits: a diagnostic pitfall

The diagnosis of pleomorphic adenoma (PA) of salivary glands is usually straightforward posing few diagnostic problems for the general surgical histopathologist. The purpose of our investigation was to present a series of 22 cases of PA of major salivary glands, each of which contained small foci of tumor within vascular spaces. This feature has previously been described very rarely in PA and may represent a significant diagnostic pitfall. The patients included 12 women and 10 men, ranging in age at diagnosis from 17 to 82 years. Histopathologically, all 22 tumors displayed the features of PA with mixed epithelial and myoepithelial growth patterns and chondromyxoid areas. None of these neoplasms showed any cytologic evidence of malignancy. In all cases, there were multiple dilated thin-walled and/or muscular thick-walled blood vessels containing small intraluminal collections of neoplastic cells with or without myxoid stromal components. The intravascular tumor cells expressed cytokeratins, and in some cases they were also immunoreactive for S-100 protein, GFAP, D2-40, and p63 protein. The intravascular location of the neoplastic cells was confirmed by CD31, CD34, and factor VIII-related antigen immunostains. Reaction for D2-40 was negative in the endothelium of the involved vessel in all cases, confirming that they were vascular rather than lymphatic channels. Seven patients (36%) underwent fine-needle aspiration biopsy 25 days to several years before excision of the tumor. Follow-up of the patients in our series revealed no cases of recurrence or metastasis (range, 6 mo to 9.5 y; mean 3.8 y; median 3.5 y). The biological significance of intravascular tumor in PA is not clear, but there is growing evidence that it is an innocuous phenomenon that might be related to artifactual spillage caused by tumor injury presumably by either fine-needle aspiration or intraoperative trauma.

Orbital infantile myofibroma: a case report and clinicopathologic review of 24 cases from the literature

Isolated orbital infantile myofibroma are rare tumors in the head and neck. The mass-like clinical presentation and variable histologic features result in frequent misdiagnosis and potentially inappropriate clinical management. There are only a few reported cases in the English literature. Twenty-four patients with orbital infantile myofibroma or myofibromatosis were compiled from the English literature (Medline 1960-2011) and integrated with this case report. The patients included 14 males and 10 females, aged newborn to 10 years (mean, 34.8 months), who presented with a painless mass in the infra- or supraorbital regions, usually increasing in size andassociated with exophthalmos (n = 5). Females were on average older than their male counterparts (38.9 vs. 31.9 months, respectively; P = 0.71). The tumors were twice as frequent on the left (n = 16) than right (n = 8). Patients experienced symptoms for an average of 2.7 months before clinical presentation. The tumors involved the bone (n = 17) or the soft tissues (n = 7) of the orbit, with extension into the nasal or oral cavity (n = 3). The mean size was 3.0 cm, with a statistically significant difference between males and females (mean: 3.9 vs. 1.82; P = 0.0047), but without any differences based on age at presentation (P = 0.25), duration of symptoms (P = 0.66), or bone or soft tissue involvement (P = 0.51). Grossly, all tumors were well-circumscribed, firm to rubbery, homogenous, and white-grey. Histologically, the tumors were biphasic, showing whorled and nodular areas of fusiform cells with extracellular collagen, mixed with a population of small, primitive-appearing, darkly staining cells. Necrosis was not present, but mitoses could be seen. Tumors with immunohistochemistry performed showed strong and diffuse smooth muscle actin and vimentin immunoreactivity, but were negative with muscle specific actin, desmin, MYOD1, myogenin, S100 protein, GFAP, keratin, CD31, 34, Factor VIIIR-Ag, and CD45RB. The principle histologic differential diagnosis includes juvenile hyaline fibromatosis, fibrous hamartoma of infancy, fibromatosis coli, leiomyoma, infantile hemangiopericytoma, infantile fibrosarcoma, Ewing sarcoma/primitive neuroectodermal tumor, and lymphoma. All patients were managed with surgery. Recurrences developed in two patients at 4 and 6 months, respectively. Follow-up data was available on all but two patients (n = 22). These patients were either alive without evidence of disease (n = 18), alive but with disease (n = 3), or had died unrelated to this disease (i.e., neuroblastoma, n = 1). Orbital infantile myofibroma is a rare tumor, presenting in infancy as an enlarging mass of the orbit, with characteristic histomorphologic and immunophenotypic features. Orbital disease is usually isolated rather than part of systemic disease, and shows an excellent long-term prognosis, making appropriate separation from other conditions important.

Unilateral breast mass in an infant: a rare presentation of spontaneously regressing myofibromatosis

Breast tumors are very rare in infants. We describe a 4-month-old female infant who presented with a firm and painless right breast mass. It was first noticed at the age of 1 month and then gradually increased in size. Further physical examination and imaging studies revealed other subcutaneous masses and lytic bone lesions. True-cut biopsy from the breast lesion was consistent with infantile myofibromatosis. Infantile myofibromatosis is a group of uncommon mesenchymal tumors that tend to occur in infancy and regress spontaneously, as demonstrated in our case. Surgical excision of such lesion might have led to permanent loss of breast tissue. The report discusses the clinical, radiological, and pathologic features, in addition to the previously described treatment options for this condition.

A partially regressed, atrophic plaque on a 17-year-old girl: an unusual presentation of myofibromatosis

Solitary cutaneous myofibromas have been reported in patients of all ages. Infantile and adult forms are distinguished by age of onset, location of lesions, and the potential for infantile myofibromas to regress. We report a case of a 17-year-old girl with a solitary myofibroma on the right leg that presented as a partially regressed, atrophic plaque with multiple surrounding papules. Unusual features of this case include the tumor size, simultaneous regression and proliferation, patient age, and gender.

Morphometric analyses of elastic tissue fibers in dermatofibroma: clues to etiopathogenesis?

BACKGROUND

The etiopathogenesis of dermatofibroma (DF), a common benign fibrohistiocytic tumor, is debatable. The goal of this study was to ascertain the density of elastic tissue fibers in DF in an effort to investigate whether this provides an insight into its etiopathogenesis.

METHOD

Three groups comprising eight cellular DFs, eight paucicellular DFs and eight scars (control group) were stained with a modified Verhoeffs-van Gieson (without counterstain), and elastic fibers in three randomly selected fields within the lesional area/case semiquantitatively analyzed and examined in a blinded fashion.

RESULT

The mean density of elastic tissue fibers in cellular DF was 6.81 (1.38-15.89); in paucicellular DF, 2.46 (0.14-5.79) and in scar, 2.95 (0.97-10.69). Overall, significant differences in density of elastic tissue fibers were observed only between cellular DF and the other two groups (vs. paucicellular variant, p = 0.03 and vs. scar, p = 0.05). Morphological changes observed included thickness, clumping, elongation and waviness (cellular DF) and margination of elastic tissue fibers (paucicellular variant).

CONCLUSION

While the jury still appears to be out regarding the etiopathogenesis of DF, the reduction in density of elastic tissue fibers in the paucicellular variant compared with its cellular counterpart lends credence to the concept of evolutionary stages of DF.

Oral myofibromas: report of two cases and review of clinical and histopathologic differential diagnosis

Myofibroma is a benign mesenchymal neoplasm composed of myofibroblasts which has been described with different synonyms since the first report in 1951. It may show clinical and histologic features that may be misinterpreted as a malignancy. We describe 2 cases of oral myofibromas affecting infants; the first one showed a rapid growth with teeth displacement and ulceration; the second one presented a relatively slow growth with an indolent course. Differential diagnosis included benign and malignant mesenchymal neoplasms, salivary gland tumors, and reactive processes. Microscopic analysis of both lesions revealed a spindle cell tumor with immunoreactivity for vimentin, muscle-specific actin, and specific smooth muscle isoform alpha-actin, rendering the diagnoses of myofibroma. The patients were treated with surgical excision, and both are in follow-up without any signs of recurrence. Myofibroma presents a wide range of differential diagnosis, including benign and malignant neoplasms. Therefore, accurate diagnosis may avoid an unnecessary aggressive therapy.

Infantile myofibromatosis

Despite being the most common fibrous tumour of infancy, infantile myofibromatosis is still sufficiently rare for the diagnosis not to be apparent to many clinicians. We present the data from the 12 cases seen in our institute over the last 14 years and highlight three cases, the first a "typical" case, then a retroperitoneal myofibroma that presented with duodenal obstruction and finally one that presented as an isolated scrotal mass. We have also reviewed the literature on the subject.

Clinico-pathologic correlations of myofibroblastic tumors of the oral cavity. II. Myofibroma and myofibromatosis of the oral soft tissues

BACKGROUND

Myofibroma is a solitary benign tumor of myofibroblasts. Myofibromatosis describes multiple, simultaneous myofibromas at different sites in various organs. The clinico-pathologic correlations of myofibroma/myofibromatosis confined only to oral soft tissues were analyzed.

METHODS

In the English language literature, 41 myofibroma and 12 myofibromatosis cases involving the oral soft tissues were found. From our files, three new myofibroma cases were added.

RESULTS

Age at time of diagnosis of oral mucosa myofibroma ranged from birth to 70 years (mean 21.7 years), considerably higher than myofibroma in other parts of the body. Lesions occurred during the first decade (44%) and in the first year of life (17%). Male:female ratio was 1:1.6, contrary to the male predominance in other parts of the body. Common sites were the tongue (32%) and buccal mucosa (18%). Treatment was local excision, either complete (n = 13) or partial (n = 3), wide excision (n = 4), surgery, and chemotherapy (n = 1). Myofibromatosis involving oral soft tissues was diagnosed at birth in nine (75%) patients, within the first year in two, and as a young adult in one. Male:female ratio was 2:1. The tongue was the most common site (50%). Half the patients died of disseminated disease within a few days from birth, three were cured by partial or complete excision, and three experienced spontaneous regression. Histologically, oral mucosa myofibroma/myofibromatosis appearance agreed with findings in the literature.

CONCLUSIONS

Myofibroma should be included in the clinical differential diagnosis of masses of the oral soft tissues, especially in the tongue and buccal mucosa of children and adolescents. Histological differential diagnosis includes benign and malignant spindle-shaped lesions. Treatment of choice is local excision.

Myofibromatosis: A case report with a unique clinical presentation

Myofibroma and myofibromatosis have been described under different names since 1951. These lesions are a benign fibroblastic and myofibroblastic proliferation containing a biphasic presentation of spindle-shaped cells surrounding a central zone of less differentiated cells focally arranged in a hemangiopericytoma-like pattern. Classically, these lesions are described in children younger than 2, with two thirds present at birth, and rarely in adults. The typical clinical presentation shows variable growth pattern of a painless purple to pink soft tissue mass, often showing secondary ulceration. Controversy exists as to an autosomal dominant or recessive inheritance versus sporadic occurrence. Presented here is a unique case of myofibromatosis presenting first as a superficial scalp lesion at age 2, followed by other primary lesions of the right mandibular vestibule, right temple, and left mandibular vestibule at ages 9, 12, and 23, respectively. All were treated with excision, without recurrence at the primary site.

[Perivascular neoplasms of skin and soft tissues. A review]

Perivascular neoplasms of skin and soft tissues comprise a group of benign and malignant mesenchymal neoplasms showing a perivascular myogenic differentiation. Whereas glomus tumour including its variants represents a clearly defined clinicopathological entity, the whole concept of haemangiopericytoma has been questioned in the last years, and no clear diagnostic criteria are established at the moment. Myopericytomas and myofibromas represent a morphological spectrum of perivascular spindle-shaped lesions. Infantile myofibroma/infantile myofibromatosis and solitary myofibroma of adults are characterized by a biphasic growth of mature, spindled, myofibroblastic cells and smaller, immature, mesenchymal cells associated with numerous haemangiopericytoma-like vessels. Benign and rare malignant myopericytomas of skin and soft tissues are characterized by a concentric, perivascular growth of plump spindled and round tumour cells staining positively for muscle actin, alpha-smooth muscle actin and more rarely for desmin. PEComas represent an enigmatic family of neoplasms composed of perivascular epithelioid, clear, and spindled tumour cells characterized by a coexpression of melanocytic and myogenic markers.

Solitary central myofibroma presenting in the gnathic region

Solitary myofibroma of adults is an uncommon neoplasm that typically arises in soft tissue and subcutaneous sites in the head and neck, but rarely within bone. When encountered in the jaws, the lesions exhibit clinical and radiographic features suggestive of an odontogenic tumor or cyst as well as several other neoplastic conditions. Tooth mobility, displacement of teeth, and dramatic jaw expansion may be observed. Analogous to other sites of involvement, gnathic myofibromas are biologically indolent and show little or no recurrence following excision. In rare instances, however, the ability to obtain adequate surgical margins by conservative measures may be limited; thus, issues of local control may supercede the importance of biologic potential. We present the radiologic and histopathologic findings in a case of central myofibroma presenting as a large lytic lesion of the mandible. Myofibroma involving the jaw bones represents a unique diagnostic and therapeutic challenge, and accurate diagnosis and management is predicated on careful correlation of radiographic and pathologic findings.

Solitary adult myofibroma of the mandible simulating an odontogenic cyst

The solitary adult myofibroma is a rare lesion but has a predilection for the head and neck. Intraosseous lesions are common in childhood but uncommon in adults. The lesion is considered to be completely benign but there is the potential for it being confused with more aggressive spindle cell tumours. Histologically it is characterised by two cell types arranged in a biphasic pattern; namely centrally positioned small rounded cells with pale staining nuclei and eosinophilic cytoplasm and peripherally elongated spindle cells. A case is reported of a 34-year-old female patient who presented with a solitary myofibroma in the lower third molar region of the mandible which clinically and radiographically simulated an odontogenic cyst.