Solitary Myofibroma Research Articles

Solitary Myofibroma of the oral and maxillofacial regions in pediatric patients: A clinicopathological analysis of ten patients and review of 75 cases

BackgroundThe imaging manifestations of oral and maxillofacial myofibroma/myofibromatosis can vary among patients. Although many clinical cases have been reported, a consensus on the clinicopathological features of and treatment principles for this disease is lacking. PurposeThis study aimed to summarize the clinicopathological features of solitary myofibroma of the oral and maxillofacial regions in pediatric patients. MethodsThe clinical data, histological features, and immunohistochemical characteristics of ten pediatric patients who underwent surgical removal and subsequent pathological diagnosis of myofibroma were collected and retrospectively and cross-sectionally analyzed. ResultsSeven patients were male, and 3 were female, with ages ranging from 3 months to 6 years (mean: 2.6 years). The patients presented with solitary lesions involving the mandibular gingiva and adjacent mandible (4 patients), mandible (2 patients), oral floor and submandibular area and adjacent mandible (1 patient), gingiva (1 patient), maxilla (1 patient), and oropharynx (1 patient). Light microscopy revealed spindle-shaped tumor cells organized in bundles or vortex patterns, forming a hemangiopericytoma-like perivascular pattern, whereas immunohistochemical staining revealed diffuse smooth muscle actin (SMA) positivity. All patients underwent surgical resection, and none experienced recurrence over the 12- to 82-month follow-up. ConclusionsSolitary myofibroma in the oral and maxillofacial regions is predominantly observed in infants and young children, with a higher incidence among males. The prognosis is favorable following localized lesion resection or curettage of jawbone lesions. Accurate recognition of the clinical, radiological, and pathological features of the disease will reduce the misdiagnosis rate.

Solitary myofibroma of the skull in a 4-year-old boy

Solitary myofibroma of the skull in a 4-year-old boy

Intramasseteric Solitary Myofibroma: A Case Report.

Solitary myofibroma or infantile myofibroma is a rare spindle cell neoplasm that generally affects infants before the age of 2 years but cases in young children and adults have been described. Although the location of infantile myofibroma in the oral and maxillofacial region has been described, the intramasseteric location of the lesion is very uncommon. A thorough assessment of histopathological and immunohistochemical characteristics is necessary to have a correct diagnosis. Treatment relies on surgical resection. In this article, we present a rare clinical case of a 15-year-old patient with a myofibroma of the masseteric muscle and its management.

Solitary myofibroma in children: a report of two cases

Myofibromas are rare benign tumors of myofibroblasts, seen more commonly in children. These tumors typically involve soft tissues with a predilection for the head and neck. Malignant neoplasia is often suspected for these rapidly growing tumors in early childhood. Clinical and radiological findings are not typical, and histopathological examination makes the definitive diagnosis. This pathology requires the intervention of a multidisciplinary team and regular follow-up. We report our experience with two children with myofibromas, one in the right arm of a 5-year-old girl and the other in the right axilla of a 9-year-old boy. Tumors were totally resected in both children, who are under follow-up with no adjuvant treatment free of disease after surgery. Myofibroma should be considered in the differential diagnosis of pediatric soft tissue tumors. Surgical resection is sufficient for treatment and patients should be followed regularly for possible recurrences.

A rare case of neonatal colonic obstruction caused by a solitary intestinal tumor

BackgroundIntestinal obstruction caused by a tumor is very rare in newborns, and the preoperative diagnosis is difficult. We herein report a rare case of neonatal colonic obstruction due to solitary intestinal myofibroma with characteristic findings on gastrografin enema and the surgical strategy.Case presentationA 4-day-old female infant presented to our neonatal intensive-care unit with abdominal distention and bilious vomiting after feeding. A gastrografin enema showed that the transverse colon near the hepatic flexure was not delineated at the oral side. When pressure was applied, a small amount of contrast material moved into the mouth in the form of threads. Microcolon was not observed, and stenosis of the transverse colon was found 9 cm from the Bauhin valve. Partial resection and end-to-end anastomosis were performed. A pathological examination of the resected specimen suggested gastrointestinal stromal tumor (GIST). After obtaining a second opinion, the histology and immunohistological markers were deemed characteristic of infantile myofibroma.ConclusionIf string sign and a napkin ring appearance are found in a case of neonatal intestinal obstruction, surgery should be performed with a tumor in mind. In cases of neonatal intestinal obstruction caused by a tumor, the lesion should be resected with a sufficient surgical margin before the pathological examination.

Intra-abdominal Solitary Myofibroma in a Child: A Rare Case Report

Intra-abdominal masses in children are usually malignant. Benign tumours at this location are not seen frequently. It is even rarer to find solitary myofibromas intra-abdominally as these tumours are known to have predilection for the head and neck region. We present an unusual case of solitary myofibroma with abdominal localisation in a six-year-old male child who presented with abdominal distension since six months. Computed Tomography (CT) abdomen revealed a complex solid-cystic mass extending from umbilicus to right iliac fossa and measuring 9×6×4 cm. Histopathological examination revealed a tumour displaying biphasic nodular pattern with the presence of lighter staining fascicles of mature myoid cells along with darker staining and more cellular areas of smaller primitive cells. On Immunohistochemistry (IHC), tumour cells were positive for vimentin and Smooth Muscle Actin (SMA) with variable reactivity for desmin while these were negative for CD34 and Anaplastic Lymphoma Kinase 1 (ALK). Based on the histopathological and immunohistochemical findings, final diagnosis of myofibroma was made. Recognition of these lesions is extremely challenging owing to their rare presentation intra-abdominally and also because of their close morphological overlap with other spindle cell tumours commonly found at this site. This case highlights the combined role played by histopathology and IHC in making a clear distinction between different entities. It is imperative for both clinicians and histopathologists to establish the correct diagnosis as excision of the solitary myofibroma is curative in most cases and offers better clinical course than the more commonly found malignant tumours at this site.

Solitary lung myofibroma in an infant

Abstract Myofibroma is a rare benign spindle cell neoplasm that occurs predominantly in infants and young children. The disease can be classified into solitary and multicentric forms. The solitary form typically affects the skin and subcutaneous tissue while the multicentric form is usually more severe due to the involvement of internal organs. A solitary myofibroma involving the lung is an extremely rare variant of this disease. To the best of our knowledge, this form of the disease has not been well documented in the literature. We report here an 8-month-old male who presented with cough and fever and was found to have a well-circumscribed lesion in his right lung. CT imaging revealed a soft tissue mass with some intratumoral calcification. A systemic examination was unremarkable. Thoracoscopic excision of the mass was successfully performed. Histopathology revealed a spindle cell tumor consistent with the diagnosis of solitary myofibroma. The patient had a stable recovery and was discharged home after 24 hours. There were no recurrences after a follow up period of 1 month.

A Rapidly Enlarging Solitary Infantile Myofibroma

Infantile myofibromatosis is a rare disorder of mesenchymal cell proliferation that can affect the skin, bone, muscle, and viscera. We present a case of a 6-week-old male with a rapidly enlarging congenital solitary infantile myofibroma. The differential for congenital tumors of the head and neck is broad, and thorough evaluation is required to rule out life-threatening malignancy. Currently, there is no first-line imaging modality of choice to assess for skeletal and/or visceral involvement in patients with infantile myofibromatosis. We recommend the use of whole-body magnetic resonance imaging (MRI), as it quickly provides detailed information regarding extent of disease and does not expose the patient to the harmful effects of radiation.

Solitary myofibroma associated with impacted third molar

Solitary myofibroma associated with impacted third molar

Solitary orbital myofibroma in a child: A rare case report with literature review

Myofibroma is a rare benign mesenchymal tumor of uncertain histogenesis. A six-year-old boy presented with a unilateral lower eyelid mass of six weeks’ duration. MRI revealed a circumscribed mass in the inferolateral orbit with bony erosion. A systemic examination was unremarkable. Excision with histopathology revealed a partially infiltrative spindle cell tumor with bland nuclear morphology expressing smooth muscle actin and muscle-specific actin, compatible with myofibroma. Solitary myofibroma is a rare childhood orbital tumor and may clinico-radiologically closely mimic a malignancy. Histopathology and immunohistochemistry can help reach a definitive diagnosis. Systemic evaluation and close follow up are crucial in such cases.

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

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

Abstract 534: PDGFRB gain-of-function mutations in multifocal infantile myofibromatosis: Implications for diagnosis & therapy

Abstract Myofibromas and infantile myofibromatosis are among the most prevalent soft tissue tumors of infancy and childhood. They are characterized by the presence of solitary or multiple nodules in the skin, subcutaneous soft tissues, bones, muscles and viscera. Multifocal myofibromatosis with visceral lesions is associated with a poor prognosis. The pathogenesis of sporadic myofibromatosis is unknown. A few familial cases have been linked to mutations in various genes including PDGFRB, which encodes a receptor tyrosine kinase that is highly expressed in fibroblasts, pericytes and other cells of mesenchymal origin. In the present study, we investigated whether the sporadic form of the disease may also be associated with PDGFRB mutations. We sequenced the whole coding sequence of PDGFRB in 20 cases of myofibromatosis or solitary myofibroma using the Ion AmpliSeq technology at high coverage (Life Technologies). Six different mutations in the coding sequence of PDGFRB were identified in seven patients, six of whom had the sporadic multicentric form of the disease, with a median age at diagnosis of 13 months [range: 0 to 7 years]. Mutations were located in four different exons: the classical hotspot exons 12 and 14, encoding the juxtamembrane and the kinase domains, but also the exons 11 and 18, encoding the transmembrane domain and the activation loop respectively. The percentage of mutated reads varied between 4 and 33%, suggesting that the mutations were somatic, except for one patient who had a germline R561C substitution and a somatic second hit. Two patients had the same mutation in multiple separated lesions, suggesting an early post-zygotic mutation in a progenitor cell. By contrast, a third patient had three different PDGFRB mutations in the three nodules analyzed. We showed that these mutations constitutively activated receptor signaling in the absence of ligand and stimulated fibroblast proliferation in vitro. Furthermore, the mutant receptors were sensitive to the tyrosine kinase inhibitor imatinib, except D850V, which was inhibited by dasatinib and ponatinib, suggesting a treatment for severe myofibromatosis. In conclusion, we identified activating PDGFRB mutations in 66% of sporadic multifocal infantile myofibromatosis cases, shedding light on the mechanism of disease development. Our results provide a genetic test to facilitate diagnosis, and preclinical data for development of molecular therapies. Citation Format: Florence A. Arts, Raf Sciot, Bénédicte Brichard, Marleen Renard, Laura A. Noël, Amélie I. Velghe, Christine Galant, Maria Debiec-Rychter, An Van Damme, Miikka Vikkula, Raphaël Helaers, Nisha Limaye, Hélène A. Poirel, Jean-Baptiste B. Demoulin. PDGFRB gain-of-function mutations in multifocal infantile myofibromatosis: Implications for diagnosis & therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 534. doi:10.1158/1538-7445.AM2017-534

PDGFRB gain-of-function mutations in sporadic infantile myofibromatosis.

Infantile myofibromatosis is one of the most prevalent soft tissue tumors of infancy and childhood. Multifocal nodules with visceral lesions are associated with a poor prognosis. A few familial cases have been linked to mutations in various genes including PDGFRB. In this study, we sequenced PDGFRB, which encodes a receptor tyrosine kinase, in 16 cases of myofibromatosis or solitary myofibroma. Mutations in the coding sequence of PDGFRB were identified in 6 out of 8 patients with the sporadic multicentric form of the disease and in 1 out of 8 patients with isolated myofibroma. Two patients had the same mutation in multiple separated lesions. By contrast, a third patient had three different PDGFRB mutations in the three nodules analyzed. Mutations were located in the transmembrane, juxtamembrane and kinase domains of the receptor. We showed that these mutations activated receptor signaling in the absence of ligand and transformed fibroblasts. In one case, a weakly-activating germline variant was associated with a stronger somatic mutation, suggesting a two-hit model for familial myofibromatosis. Furthermore, the mutant receptors were sensitive to the tyrosine kinase inhibitor imatinib, except D850V, which was inhibited by dasatinib and ponatinib, suggesting a targeted therapy for severe myofibromatosis. In conclusion, we identified gain-of-function PDGFRB mutations in the majority of multifocal infantile myofibromatosis cases, shedding light on the mechanism of disease development, which is reminiscent of multifocal venous malformations induced by TIE2 mutations. Our results provide a genetic test to facilitate diagnosis, and preclinical data for development of molecular therapies.

Recurrent Somatic PDGFRB Mutations in Sporadic Infantile/Solitary Adult Myofibromas But Not in Angioleiomyomas and Myopericytomas.

Infantile myofibroma (MF) is an uncommon benign myofibroblastic tumor of infancy and childhood. Solitary adult MF shares similar features with infantile MF. The lesions occur in 3 clinicopathologic settings: solitary, multicentric, and generalized and can be either sporadic or familial. Traditionally, infantile MF has been included in the spectrum of infantile hemangiopericytoma. The recent World Health Organization classification listed MF, angioleiomyoma, and myopericytoma under the general heading of perivascular tumors in the sense of a morphologic spectrum of perivascular myoid cell neoplasms. Although activating germline PDGFRB mutations have recently been linked to familial infantile MF, the molecular pathogenesis of sporadic infantile and adult solitary MF remained unclear. In this study, we analyzed 25 solitary MFs without evidence of familial disease (9 infantile and 16 adult MFs) to address the question whether somatic PDGFRB mutations might be responsible for the sporadic form of the disease. Given the presumed histogenetic link of MF to myopericytoma and angioleiomyoma, we additionally analyzed a control group of 6 myopericytomas and 9 angioleiomyomas for PDGFRB mutations. We detected PDGFRB mutations in 6/8 (75%) analyzable infantile and in 11/16 (69%) adult MFs but in none of the angioleiomyomas or myopericytomas. In 2 infantile MFs, additional sequencing of the germline confirmed the somatic nature of PDGFRB mutations. To our knowledge, this is the first study reporting apparently somatic recurrent PDGFRB mutations as molecular driver events in the majority of sporadic infantile and adult solitary MFs. Our results suggest molecular distinctness of MF as compared with angioleiomyoma/myopericytoma. Investigation of more cases including those with atypical and worrisome features, as well as other mimickers in the heterogenous morphologic spectrum of MF, is mandatory for validating the potential diagnostic value of PDGFRB mutation testing as a possible surrogate in difficult-to-classify lesions.

Myofibroma of the mandible – Case report

BackgroundMyofibroma is a benign mesenchymal neoplasm consisting of myofibroblasts proliferation. It is uncommon in the oral cavity and only a few cases were reported about the solitary myofibroma within the mandible. MethodsThis article is reporting a case of central myofibroma involving the right side of the mandible of a 13-year-old girl with the clinical, radiologic, histological and immunohistochemical management for diagnosis and treatment. ResultsThe clinical and imaginological aspects suggested a widespread odontogenic and non odontogenic lesions In the histopathological examinations, a biphasic pattern of the spindle and round-shaped cells was revealed. Immunohistochemical reaction was shown as positive diagnosis to Smooth Muscle Actin. These findings indicated the myofibroblastic nature of the cells. Our results provided the diagnosis of myofibroma. ConclusionThe clinical, imaginological and histological features indicated that the uncommon intraosseous myofibroma should be considered in differential diagnosis of widespread odontogenic and non odontogenic intraosseous mandibular lesions.

Solitary Myofibroma of the Bladder Trigone in a 3-Month-Old Patient: First Case Report.

Visceral solitary myofibromas are uncommon in childhood. We report a case of a solitary asymptomatic visceral myofibroma of the bladder trigone occurring in a 3-month-old boy. Once malignancies were ruled out by cystoscopy, radical excision was performed in order to avoid any potential impairment of bladder dynamic. Postoperative course was uneventful and patient was discharged on day 3 after surgery. After 36 months of follow-up, the patient is toilet-trained and remains well; bladder function is normal.

A Pediatric Case of Solitary Myofibroma

A 5-year-old male was referred to our department for evaluation of a firm elastic mass at the back of his head. Clinical examination revealed no abnormalities but the local area was tender. Further clinical and radiological examinations yielded no pathological findings and no other lesions were detected. The lesion was located in the diploic layer of the left parietal bone. The inner layer of the skull intact but the outer layer showed osteolytic change. The lesion did not adhere to the dura mater. The tumor was completely removed with the surrounding bone. Histological examination revealed a mesenchymal tumor comprised of myoid spindle-shaped cells arranged in whorls between muscle cells and fibroblasts and a vascular component around the spindle cells. The final diagnosis was myofibroma. The patient recovered well after the operation and he was discharged from hospital 10 days after surgery. Clinical and radiological follow-up 6 and 12 months later showed neither recurrence of the primary lesion nor any indications of lesions at other sites. Myofibroma is a benign neoplasm composed of myoid cells with thin-walled blood vessels. This tumor, reported to have a wide range of clinical manifestations, is one of the cranial vault tumors. These tumors occur mainly in children although a few affected infants have been reported. Surgical intervention may contribute significantly to the diagnosis of solitary myofibroma and complete removal achieves good outcomes. Herein, we report a 5-year-old male with solitary myofibroma of the skull, presenting as a firm elastic mass in the left parietal bone.

Huge Extra-Calvarial Infantile Myofibroma: A Case Report and Review of Literature

Infantile myofibroma is the most common benign, mesenchymal tumor found in this age group but as compared to the vast variety of benign tumors found in infants this has been rarely identified. Clinically a solitary lesion of infantile myofibroma can present with a wide variety of symptoms depending on the site of the lesion. However, infantile myofibromas can also be asymptomatic. Rarely, a lesion affecting the respiratory center can be fatal. We present the largest solitary infantile myofibroma found in the head and neck region in this case report. A comparison with other reported cases of head and neck infantile myofibroma is also mentioned in this report.

Polyorchidism associated with a solitary testicular myofibroma: Case report and current literature review

Polyorchidism associated with a solitary testicular myofibroma: Case report and current literature review

Solitary intestinal myofibroma – an unusual cause of neonatal intestinal obstruction

Congenital solitary myofibroma is an exceptional tumor of newborn period and presents as solitary or multiple lesions usually confined to soft tissues. It induces intestinal obstruction or perforation, which most frequently involves the jejunum and ileum. However, jejunoileal atresia is the most frequently encountered cause of small bowel obstruction in the neonatal period. We report a new case of solitary myofibroma located in the wall of the ileum, measuring 2×3 cm2 in size, about 25 cm from the ileocecal junction, in a 17-day-old baby girl who presented with abdominal distention and bilious vomiting. Laparotomy was performed on the patient and the tumor was removed; the patient did well after surgery. Despite all the common causes of intestinal obstruction—intestinal atresia, Hirschsprung disease, anorectal anomaly, malrotation, and meconium passage problem in the neonatal period—myofibroma of the small bowel has to be considered because treatment is fairly easy and prognosis is excellent.