Myofibroma of the mandible. Clinicopathologic study and review of the literature

Mandibular Myofibroma and Severe Trismus: A Complex Case and Review of Complications

A female child was investigated for insidious onset of temporomandibular joint dysfunction and trismus in the setting of a mandibular myofibroma. Myofibromas, benign mesenchymal neoplasms composed of spindle cells, are rarely found in the oral cavity, most commonly in the mandible. These lesions are historically described as indolent with a high cure rate and minimal recurrence rates following surgical resection. The patient initially presented with concerns regarding snoring, retrognathia, and jaw ankylosis, as well as a history of trouble latching as an infant but without obvious physical deformities. Imaging revealed a large expansile lytic mass of the mandible, but no temporomandibular joint involvement; surgical biopsy evidenced myofibroma, and the lesion was resected. Over the course of disease, the lesion continued to expand, and the patient’s maximal incisal opening continued to decrease despite conservative management with jaw physiotherapy; eventually she could not open her mouth despite the absence of joint involvement. Re-exploration along with formal jaw physiotherapy was achieved and optimal jaw opening was maintained. Myofibromas are rare benign desmoid tumors that can present anywhere in the body in solitary and multicentric forms, and previously did not present significant challenges to surgical and medical management. Tumors of the mandible may present with trismus and soft tissue ankylosis, which can mimic temporomandibular joint dysfunction in the absence of joint involvement. Physical therapy, rehabilitation, and soft tissue contracture release are key to management and improving outcomes in oral cancer patients, regardless of tumor pathology.

Mesenchymal Neoplasms of Salivary Glands: A Clinicopathologic Study of 68 Cases

Salivary gland neoplasms are uncommon, and most exhibit epithelial differentiation. Mesenchymal neoplasms of the salivary gland are rare, and the incidence ranges from 1.9% to 5%. The aim of this study is to identify the types and clinical-pathological features of mesenchymal salivary neoplasm and review their differential diagnosis. A retrospective search for mesenchymal neoplasms of salivary glands from our institution's pathology archives from the 2004-2021 period and consultation files of one of the authors (AER) was performed. The clinical data were obtained from available medical records, and the histological slides and ancillary studies were retrieved and reviewed. We identified a total of 68 cases that form the study cohort. Thirty-five patients were male, and thirty-three patients were female, with a mean age of 48 years (range, 7 months-79 years), and the male to female ratio was 1:.94. Sixty-three (92.6%) of sixty-eight tumors were benign and included: 38 (56%) lipomas, 9 (13%) hemangiomas, 7 (10.3%) schwannomas, 3 (4.4%) neurofibromas, 3 (4.4%) lymphangioma, 2 (3%) solitary fibrous tumors, 1 (1.5%) myofibroma. Five of sixty-eight (7.4%) were malignant and included: 3 (4.4%) Adamantinoma-like Ewing sarcomas, 1 (1.5%) malignant peripheral nerve sheath tumor (MPNST), and 1 (1.5%) malignant solitary fibrous tumor. The involved sites included: parotid (55), submandibular gland (5), parapharyngeal space (5), buccal mucosa minor salivary gland (2), and sublingual gland (1). Sixty-seven patients underwent surgical resection. One patient with lymphangioma manifested a recurrence/persistence a week post-surgery. One patient with a parotid hemangioma developed post-operative numbness, and another patient developed chronic postauricular pain after surgery. Two patients with MPNST and one patient with adamantinoma-like Ewing sarcoma underwent neoadjuvant chemoradiation and were disease-free after treatment. The remaining 37 patients with available follow-up ranging from 7 days to 96 months (mean, 18 months) had a favorable outcome and were disease-free after treatment. Mesenchymal neoplasms of salivary gland are rare; most are benign and demonstrate adipocytic, endothelial, and schwannian differentiation; awareness of their development is important for adequate diagnosis. The mainstay of treatment is surgical excision, with the extent determined by tumor type. Adjuvant therapy is reserved for high-grade sarcomas and may be given in a neoadjuvant or adjuvant setting.

Benign connective and soft-tissue neoplasms of the oral and maxillofacial region: Cross-sectional study of 1066 histopathological specimens

BACKGROUND

Benign connective and soft-tissue neoplasms (CSTNs) are unusual in the head and neck region. The aim of the present study was to evaluate the demographic and clinicopathological features of these neoplasms.

METHODS

A cross-sectional study was conducted of cases diagnosed as benign CSTNs, with data collected from biopsy records. The chi-square test was used. A p-value <0.05 was considered indicative of statistical significance.

RESULTS

Among the 38 119 specimens, 1066 (2.79%) were benign CSTNs: 369 fibroblastic/myofibroblastic, 250 adipocytic, 179 vascular, 130 neural, 94 osseous/cartilaginous, 19 muscular, and two fibrohistiocytic. Most patients were female (62.8%) and white-skinned (45.8%). Mean age was 42 years. The tongue (25.2%) was the most affected site for extraosseous neoplasms.

CONCLUSION

This study had the largest sample of benign oral and maxillofacial CSTNs. Although these tumors have similar clinical features, the characterization and differentiation detailed here may help clinicians with regards to the correct diagnosis.

Infantile myofibromatosis treated by mandibulectomy and staged reconstruction with submental flap and free fibula flap: a case report

BACKGROUND

Infantile myofibromatosis is the most common benign fibrous tumor in infants. Three different types have been reported in the literature. The most commonly affected areas are the head, the neck and the trunk. Our patient showed a very high level of mandibular destruction resistant to all mandibular sparing treatment strategies requiring segmental mandibulectomy and complex reconstruction.

CASE PRESENTATION

We describe a rare case of multicentric infantile myofibromatosis with mandibular bone destruction. The treatment required a succession of chemotherapy, a subtotal transoral resection and a hemi-mandibulectomy. The mandibular reconstruction was staged with initial bridging titanium plate with a submental flap, followed later by a fibula free flap.

CONCLUSION

Mandibular involvement by myofibromatosis is rare, and the extend of bone destruction and reconstruction make this case unique. To our knowledge, this is the only reported case of fibula free flap mandibular reconstruction in a patient with infantile myofibromatosis , as well as one of the youngest reported submental island flaps for any pathology. We describe the clinical presentation and management, including relevant imaging, histopathology, medical and surgical treatment as well as a review of relevant literature.

Solitary Intra-Osseous Myofibroma of the Jaw: A Case Report and Review of Literature

Myofibroma is a rare benign spindle cell neoplasm in children that usually affects both soft tissue and bone in the head and neck region. Approximately one third of these cases are seen within jaw bones as solitary lesions. Solitary intra-osseous myofibroma of the jaw bone shares its clinical, radiographic and histological features with other spindle cell tumors. The rarity of this lesion can make diagnosis difficult for clinicians and pathologists. We report a case of a solitary intra-osseous myofibroma in the mandible of a nine-year-old child.

Solitary Myofibroma of the Mandible in a Six-Year Old-Child: Diagnosis of a Rare Lesion

Myofibroma is a benign uncommon fibroblastic tumour originating from the soft tissue, bone and may affect both children and adults. Radiographically myofibroma presents as unilocular radiolucency. Histologically, typical biphasic cellular arrangement is noted. Immunohistochemical markers are useful for definitive diagnosis of this uncommon neoplasm. Here, a case of six-year-old male child with a localized swelling in the left body of mandible is presented. The clinical, radiological, histological and immunohistochemical findings were corroborative of Infantile Myofibroma.

Head and neck solitary infantile myofibroma: Clinicopathological and immunohistochemical features of a case series

Infantile myofibroma is a rare mesenchymal benign tumor mostly found in the head and neck region. The aim of this study was to describe a small case series of head and neck solitary infantile myofibroma, emphasizing the importance of the histopathological and immunohistochemical features, and the potential diagnostic challenges. For the study, clinical and imaging data were obtained from the medical records. All cases were histologically reviewed, and immunohistochemical analyses were performed to confirm the diagnosis. Four cases of head and neck solitary infantile myofibroma were identified. All patients were females and presented a mean age of 3 years old (ranging from 2 to 6 years). The site of the tumors were the mandible, right cheek, subcutaneous tissue adjacent to basal cortical of the mandible and upper anterior gingiva. No symptoms, such as pain or paresthesia, were reported. Computerized tomography revealed well-delimited tumors. All tumors were positive for vimentin and alpha-smooth muscle actin. All patients underwent surgical excision and no signs of recurrence were observed after long-term follow-up. In summary, head and neck solitary infantile myofibromas are rare and present excellent prognosis. The correlation between clinical, histopathological and immunohistochemical features are essential for a correct diagnosis.

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.

A case report of solitary, intraosseous, adult-onset myofibroma of the mandible

Myofibroma is a benign proliferation of myofibroblasts in the connective tissue. Solitary intraosseous myofibromas are a rare finding especially in an adult. Myofibroma is a benign lesion and its treatment is similar to any other benign lesion.This article reports a rare case of a 32 year old lady presenting with a complaint of a painful swelling in the lower third molar region, on examination the tender swelling had expansion of the buccal cortex. The diagnostic work up included OPG radiograph, CT Scan, and a deep incisional biopsy of the mass under L.A. The final diagnosis of myofibroma was made only after the histopathological diagnosis and Immunohistochemistry (IHC). The patient was treated with wide local excision of the lesion in the mandible under GA.

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.

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.

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.

Leiomyosarcomas of the oral cavity: an unusual topographic subset easily mistaken for nonmesenchymal tumours

AIMS

Oral leiomyosarcoma is rare and poorly documented. We aimed to characterize these lesions clinicopathologically in order to facilitate their distinction from other spindle cell neoplasms in the oral cavity.

METHODS AND RESULTS

Ten cases of oral leiomyosarcoma were retrieved and studied histologically and immunohistochemically. Clinical data were obtained from referring pathologists and prior literature concerning 46 comparable cases was reviewed. Nine out of 10 cases occurred in adults; 50% arose in the jaws and four showed bone involvement. Histological appearances were similar to leiomyosarcomas elsewhere. In addition to myogenic markers, two cases were also keratin-positive. Four patients developed local recurrence or metastatic disease and three died of tumour (median follow-up 37 months).

CONCLUSIONS

Leiomyosarcoma is under-recognized in the mouth, often being mistaken for a spindle-celled epithelial neoplasm. Aside from an unusual but infrequent tendency to spread to lymph nodes and a location-specific differential diagnosis, its clinicopathological features are comparable to leiomyosarcomas at other locations.

Myofibromas presenting in the oral cavity: a series of 9 cases

OBJECTIVES

Solitary myofibromas are well described in the head and neck, but oral examples are less well known, and jaw lesions are rare. We studied the clinicopathologic features of a series of such lesions.

DESIGN

Nine cases of oral myofibromas were retrieved from archives and studied.

RESULTS

Two cases involved the mandible (intraosseous), 3 involved the gingiva, 2 involved the tongue, and 2, the hard palate. There were 4 men and 5 women, aged 9 months to 50 years (mean, 24 years; median, 27 years). Deep lesions showed typical histology, with paucicellular lobules and intervening hemangiopericytoma-like zones. In ulcerated submucosal lesions, these features blended superficially with cellular fascicles. The tumors expressed smooth muscle actin but lacked desmin and S100 protein. None of the tumors recurred or metastasized.

CONCLUSION

Myofibromas appear in osseous, intramuscular, and submucosal aspects of the oral cavity. Ulceration imparts a fascicular appearance that makes superficial biopsy specimens difficult to interpret.

Myofibromas and myofibromatosis of the oral region: A clinicopathologic analysis of 79 cases

The clinicopathologic features of 79 myofibromas or myofibromatoses of the oral and maxillofacial region were studied. The case studies were taken from the files of the Armed Forces Institute of Pathology. The tumors affected 44 males and 33 females (gender was unknown in 2 cases). The patients' ages at diagnosis ranged from birth to 84 years, with mean and median ages of 26.6 and 22 years, respectively. Four patients had infantile myofibromatosis; 2 had extraoral bone lesions and 2 had multiple subcutaneous tumors. In descending order, tumors involved the mandible, tongue, lips, cheek or buccal area, maxilla or palate, pterygomandibular raphae, floor of mouth, and submandibular gland. One third of the tumors affected the bones of the jaws; 12 were central and 15 were cortical or periosteal. All medullary tumors occurred in patients under age 18. On gross examination, the lesions were firm, homogeneous or whorled, white-grey fibrous masses that ranged in size from 0.5 to 5.0 cm. Microscopically, all tumors demonstrated a pattern of nodules or bundles of spindle cells separated by areas of greater cellularity and crescent-shaped vascular spaces. Distinct hemangiopericytoma-like areas were present in 22 cases. Despite apparent circumscription, the tumors commonly infiltrated and entrapped adjacent muscle, nerve, or salivary tissue. Immunohistochemically, 37 of 37 and 39 of 39 tumors stained positively for alpha-smooth muscle actin and muscle-specific actin, respectively, with the former eliciting a more intense reaction. Eight of 8 tumors were weakly positive for CD68, and one case stained focally with S-100 protein. No desmin staining was present in 36 tumors examined. Diagnostic interpretations by the pathologists seeking consultation were malignant or aggressive tumors in 31 cases and other benign conditions in 26. Nine were interpreted as myofibromatosis and 13 offered no interpretation. Thirty-two patients were alive and free of tumor an average of 42 months after initial diagnosis. Four patients had one recurrence each, and 2 had lesions recur twice. Myofibromas are relatively common soft tissue tumors of the maxillofacial region, which have been misinterpreted as malignant or aggressive lesions.

Primary leiomyosarcoma of the mandible in a 7-year-old girl: report of a case and review of the literature

Leiomyosarcoma is a malignant neoplasm of smooth muscle origin that manifests itself uncommonly in the oral cavity because of the paucity of smooth muscle in that location. To the best of our knowledge, only 10 cases of leiomyosarcoma primary to the jawbones have been reported in the English language literature. We report the first pediatric case of leiomyosarcoma arising from the mandible. Facial asymmetry and swelling were accompanied by a rapidly growing exophytic soft tissue mass that caused buccal displacement of the mandibular left permanent first molar. The lesion, observed radiographically as an extensive ill-defined area of osteolytic alveolar destruction, perforated the lingual cortex, displaced the inferior alveolar nerve canal inferiorly, and produced a "floating-in-air" appearance of the first molar. Diagnosis of leiomyosarcoma was made after initial incisional biopsy of the lesion. A 5-cm segmental mandibulectomy and supraomohyoid neck dissection were followed by reconstruction with a dynamic mandibular reconstruction plate and placement of a multidimensional mandibular distraction device in a transport rectangle of bone to promote bifocal distraction osteogenesis. Forty millimeters of distraction (the technical limit of the device) were performed; this was followed by terminal iliac crest bone grafting. Seventeen months after the definitive surgical procedure, the patient remains free of disease.