Ossifying fibromyxoid tumor: a study of 6 cases of atypical and malignant variants

Ossifying Fibromyxoid Tumor of Soft Parts in the Head and Neck: A Systematic Review Addressing Surgical Management and Adjuvant Therapies

Background: Ossifying fibromyxoid tumors (OFMTs) are rare mesenchymal neoplasms with behaviors ranging from benign to malignant. Although most occur in the extremities and trunk, 9-13% are found in the head and neck, such as the oral cavity, scalp, and calvarium. Diagnosis is challenging due to their rarity and histological similarity to other neoplasms. This review synthesizes evidence on the clinical presentation, diagnostic features, and treatment outcomes of OFMTs in the head and neck, focusing on surgical management and adjuvant therapies. Methods: A systematic review was conducted according to PRISMA guidelines, with searches in PubMed/MEDLINE, Embase, Scopus, and Web of Science. Studies from 1989 to 2024 reporting OFMTs in the head and neck with clinical, histopathological, and treatment data were included. Extracted data encompassed demographics, tumor features, surgical margins, adjuvant therapy, and outcomes. Results: Forty studies with 99 patients were included. Patient ages ranged from 3 weeks to 88 years (median 47), with a male predominance (63.64%). The most common presentation was a slow-growing, painless mass. Tumors were most often found in the neck, oral cavity, scalp, and calvarium. Histopathology revealed encapsulated tumors with fibromyxoid stroma, spindle-shaped cells, and a peripheral rim of metaplastic bone in 70% of cases. Immunohistochemistry showed positivity for S-100, vimentin, and SOX10. Surgical excision was the main treatment, used in 28.28% of cases, with recurrence in 9.09% and no metastases. Adjuvant therapies, mainly radiotherapy, were employed in 15.15% of cases. Conclusions: OFMTs of the head and neck are rare neoplasms requiring multidisciplinary care. Imaging, histopathology, and immunohistochemistry are key to diagnosis. Surgical excision with clear margins remains the primary treatment, with a low recurrence rate. Adjuvant therapy may be needed for malignant or incompletely excised cases. Further research is needed to optimize follow-up protocols and assess molecular profiling for risk stratification.

A potential conundrum in dermatopathology: molecularly confirmed superficial ossifying fibromyxoid tumors with unusual histomorphologic findings and a novel fusion

Ossifying fibromyxoid tumor (OFMT) is a rare soft tissue neoplasm of uncertain histogenesis, primarily arising in subcutaneous tissues of the extremities, head and neck, or trunk. Most cases present as well-circumscribed masses with a characteristic morphologic appearance, comprising cytologically bland ovoid cells with fibromyxoid stroma, a peripheral rim of metaplastic bone, and lobulated architecture. Nevertheless, tumors displaying unusual morphologic characteristics pose significant diagnostic challenges, requiring the detection of a pathogenic fusion for a definitive diagnosis. The majority of OFMTs exhibits PHF1 gene rearrangements. Herein, we present six cases of molecularly confirmed OFMTs with uncommon histomorphologic features, including the absence of myxoid stroma, extensive chondroid differentiation, prominent clear cell morphology, collagen entrapment, interdigitating fibrocollagenous and fibromyxoid stromal elements, and conspicuous red blood cell extravasation. One case harbored a novel fusion (EPC1::SUZ12). This study emphasizes the broad range of morphologic manifestations that can be encountered in OFMT and the crucial role of molecular testing in establishing a conclusive diagnosis in such cases.

When molecular outsmarts morphology: Malignant ossifying fibromyxoid tumors masquerading as osteosarcomas, including a novel CREBZF::PHF1 fusion

We present two cases of malignant ossifying fibromyxoid tumor (OFMT) which eluded diagnosis due to compelling clinicopathologic mimicry, compounded by similarly elusive underlying molecular drivers. The first is of a clavicle mass in a 69 year-old female, which histologically showed an infiltrative nested and trabeculated proliferation of monomorphic cells giving rise to scattered spicules of immature woven bone. Excepting SATB2 positivity, the lesion showed an inconclusive immunoprofile which along with negative PHF1 FISH led to an initial diagnosis of high-grade osteosarcoma. Next generation sequencing (NGS) revealed a particularly rare CREBBP::BCORL1 fusion. The second illustrates the peculiar presentation of a dural-based mass in a 52 year-old female who presented with neurologic dyscrasias. Sections showed a sheeted monotonous proliferation of ovoid to spindle cells, but in contrast to Case #1, the tumor contained an exuberance of reticular osteoid and woven bone deposition mimicking malignant osteogenic differentiation. NGS showed a novel CREBZF::PHF1 fusion. Both tumors recurred locally less than 1 year post-operatively. As such we reiterate that careful morphologic examination is axiomatic to any diagnosis in our discipline, but this paradigm must shift to recognize that molecular diagnostics can provide closure where traditional tools have notable limitations.

Malignant Ossifying Fibromyxoid Tumor of the Chest Wall Metastasized to the Lung Even After Complete Resectioning of the Primary Tumor - A Case Report and a Comprehensive Review

An ossifying fibromyxoid tumor is a soft tissue neoplasm with ambiguous differentiation and low metastatic potential. Most cases involve the lower extremities, followed by the trunk, the upper extremities, and the head and neck region. It mainly arises in 40-70 years of age, and men dominate the disease's gender distribution. In the described types of ossifying fibromyxoid tumors, there are three variants: one is benign (typical), the second is malignant, which carries the risk of disease recurrence or metastases, and the third is atypical, which does not meet the criteria of either typical or malignant. Here, we present an interesting case of a malignant ossifying fibromyxoid tumor of the chest wall that metastasized to the lungs even after complete resection of the primary tumor. A 64-year-old man had a 4.0 cm malignant ossifying fibromyxoid tumor in his chest wall two years ago, and at that time, the tumor was removed entirely. On pathology review, it was noted to have 20 mitotic figures per 50 high-power fields, but no actual grade was given. He was given postoperative radiation. His recent computed tomography (CT) chest with contrast showed a new right upper lung lobe nodule measuring 0.78 cm compared to the previous contrast-enhanced CT chest six months ago. It was worrisome for metastasis. F-18 FDG positron emission tomography scan revealed sub-centimetric pulmonary nodules in the right upper lobe. Right upper lobe lung biopsy showed spindle cell neoplasm morphologically consistent with the patient's known history of malignant ossifying fibromyxoid tumor. Biopsy demonstrated fragments of the bronchial wall and alveolated lung parenchyma with a focal spindle cell proliferation demonstrating a fibromyxoid matrix. The patient was referred to the oncologist for further management. In conclusion, aggressive malignant ossifying fibromyxoid tumors can be found in atypical locations, e.g., the chest wall. Therefore, early diagnosis is crucial because of the high chances of metastasis to distant organs (including the lung) even after complete resection of the primary tumor. Even in asymptomatic patients, it is necessary to complete long-term follow-up for recurrence and metastasis surveillance of ossifying fibromyxoid tumors. Early recognition of recurrence or metastasis can decrease morbidity and mortality and improve overall organ function and patient survival.

Malignant ossifying fibromyxoid tumor of the calvaria: illustrative case

BACKGROUND

Ossifying fibromyxoid tumor (OFMT) is a rare entity of soft tissue tumor that most commonly occurs in the subcutaneous tissues of trunk or extremities with occasional cases involving the head and neck; however, primary involvement of the skull has not been reported. While historically considered slow-growing benign to intermediate malignant, few cases of atypical or malignant features have been described.

OBSERVATIONS

Herein, the authors present a case of malignant OFMT with primary skull and transcranial extension. The tumor caused lytic calvarial destruction with intra- and extracranial soft tissue components. Gross total resection was performed, and histopathology revealed malignant OFMT with 40 mitoses per 50 high-power fields and moderate nuclear atypia.

LESSONS

OFMT can rarely occur in the head and neck and, as reported herein, may involve the skull with intracranial extension. While no uniformly recognized histological criteria for malignancy exist, a three-tiered classification has been proposed: typical, atypical, and malignant, based on features such as hypercellularity, mitotic activity, infiltrative growth, and/or nuclear atypia. Malignant variants should be considered along the high-grade sarcoma spectrum with elevated risk for recurrence or metastatic spread. Routine adjuvant radiotherapy is not typically recommended; however, surveillance imaging is advised.

Ossifying fibromyxoid tumor of soft tissue: A case report with review of literature

Introduction and importance

The ossifying fibromyxoid tumor of soft tissue is a rare tumor of intermediate differentiation and uncertain lineage that occurs in adults mostly in the extremities and the trunk.

Presentation of case

we present a case of 57 year-old man presenting with a right scapular mass. It was a subcutaneous and painless mass that was largely excised. The diagnosis of ossifying fibromyxoid tumor of the right shoulder was made. The follow up of 1 year was without recurrence and metastasis.

Clinical discussion

The ossifying fibromyxoid tumor of soft tissue is exceptional, microscopic diagnosis and management is challenging, considering the scarcity of the tumor.

Conclusion

More cases and retrospective studies are needed to understand the pathogenesis and to determine optimal treatment regimens.

Ossifying fibromyxoid tumor of the oral cavity: rare case report and long-term follow-up

Ossifying fibromyxoid tumor (OFMT) is a rare mesenchymal soft tissue benign neoplasm with an uncertain line of differentiation, which arises most frequently in extremities. The head and neck region involvement is uncommon, with only ten intraoral cases published in the English-language literature. One additional case of OFMT is reported here, including a literature review of intraoral reported cases. A 45-year-old female patient presented a painless nodule involving the buccal mucosa of approximately two years duration, measuring nearly 1.3 cm in maximum diameter. The main histopathological features include ovoid to round cells embedded in a fibromyxoid matrix with a perpheral shell of lamellar bone. Immunohistochemically, the tumor showed immunoreactivity for vimentin and S100. No recurrence has been detected after 7 years of follow-up.

Primary malignant ossifying fibromyxoid tumour of the bone. A clinicopathologic and molecular report of two cases

Objective

To report the exceptional occurrence of ossifying fibromyxoid tumour (OFMT) as a primary bone lesion. OFMT is a rare soft tissue tumour of uncertain differentiation and variable malignant potential, that occurs in adults with a slight male predominance. It is typically located in the subcutis or in the skeletal muscles of the extremities, followed by trunk or head and neck.

Methods

Two cases of OFMT proven to arise from bone are presented. The first is a 65-year old female with a history of rib "osteosarcoma", presenting with an inferior lobe left lung mass. The second is a man with a lytic lesion of the 5th cervical vertebra that recurred shortly after resection. Following H&E and immunohistochemical examination, tumour samples were analysed by NGS and by break-apart FISH to detect rearrangement of the PHF1 and TFE3 genes.

Results

PHF1 gene-rearrangement was identified by FISH on both the primary and the metastatic lesion of first patient. NGS identified a PHF1(intron1) and EPC1 (exon 10) fusion transcript later confirmed by positive PHF1 rearrangement on FISH in the second case.

Conclusions

The demonstration of PHF1 gene rearrangements represents a fundamental ancillary diagnostic test when presented with challenging examples of OFMT.

Ossifying fibromyxoid tumor: a rare case

Ossifying fibromyxoid tumour (OFMT) is a rarely occurring soft tissue neoplasm of mesenchymal origin. It is a rarely found tumour with intermediate behaviour and differentiation. Although it is mostly benign, malignant variants also exist. We are presenting a case of 32-year-old man presented in clinic with complaints of painless swelling in left distal thigh. After reviewing his X-ray, a diagnostic biopsy was planned which came out to be suspicious of solitary fibrous tumour. Other radiological workup was done and the patient was planned to undergo wide margin excision. The final histopathology showed a diagnosis of OFMT of soft tissue, atypical variant. The patient is under follow-up and is disease free. This type of tumour possesses potential of local recurrence and metastases; therefore, it is important to keep a long-term follow-up of patient.

Ossifying Fibromyxoid tumor of soft parts in head and neck: case report and literature review

Background

Ossifying fibromyxoid tumor of soft parts (OFMT), is a rare but morphologically distinctive neoplasm of uncertain histogenesis that most frequently affects middle-aged male adults. Clinically, it usually presents as a slowly enlarging, small, circumscribed mass, which in most cases is painless. OFMT is most frequently found within the subcutaneous tissues of extremities or trunk, and rarely in the oral/head and neck region. We present an unusual case of this tumor in the submandibular region, and, based on the current medical literatures this is probably the first case described in this anatomical location.

Case presentation

A 32-year-old male presented to our outpatient clinic with a right submandibular mass with 1-year of evolution. Excisional biopsy showed that it was characterized by ossification along the periphery of the lesion. The neoplastic cells were spindle-like with scant eosinophilic cytoplasm. These cells were arranged with uniform cell-to-cell space in a fibromyxoid stroma. Small and large clusters of calcifications were present within the tumor. Immunohistochemically, the case showed positive staining of S-100 protein, vimentin, nestin, calponin, SMA, GFAF, desmin, INI-1, caldesmon, and CD34. It also showed negative staining of CK, CK7, CK8/18, NF, and EMA. About 2% of neoplastic cells showed positive staining of Ki67. Based on these features, the final pathological diagnosis was OFMT.

Conclusions

It is hoped that a greater understanding of OFMT in the head and neck region will avoid potential misdiagnosis, and contribute to determining the correct management, which appears to be complete surgical excision with close follow-up for recurrence surveillance.

A rare case report of a typical variant ossifying fibromyxoid tumor (OFMT), located in the retroauricular perimastoid region

INTRODUCTION

Ossifying fibromixoid tumor of soft parts (OFMT) is a rare soft tissue and bone tumor. In its classic form, is considered benign, nevertheless aggressive clinical behaviour tumors with a different cytoarchitectural features of a malignant variant, have been described.The classification contains "typical", "atypical" and "malignant" variants.

METHODS

A CT ear scan without contrast enhancement was carried out (October 2015), with coronal, sagittal and 3D reconstructions. It was decided the removal of the neoformation with a simple dissection.

RESULTS

In this report, we present a case of a typical variant OFMT localized in the retroauricular perimastoid region, with mastoid bone cortex not involved.

CONCLUSIONS

Considering the extreme rarity of this "enigmatic" tumor which displays an uncertain line of differentiation, renders the differential diagnosis a true challenge.

Response to isolated limb perfusion and chemotherapy with epirubicin plus ifosfamide in a metastatic malignant ossifying fibromyxoid tumor

Background

Ossifying fibromyxoid tumor (OFMT) is a rare soft tissue neoplasm of uncertain lineage and intermediate biological potential. It is more common in middle-aged men, usually arising from the deep tissues of the extremities. It is now established that it is a translocation related tumor, most often marked by translocation of PHF1 gene. Surgery is the mainstay of treatment and proves usually curative, although, in rarer cases the disease shows malignant features and tendency to recur both locally and at distant sites. In such cases, no standard treatment exists.

Case presentation

We report on a case of malignant advanced OFMT of the hand with lung metastases responding to isolated limb perfusion with human recombinant tumor necrosis factor and melphalan and chemotherapy with epirubicin and ifosfamide.

Conclusions

To our knowledge, this is the first report of activity of soft tissue sarcoma-oriented chemotherapy in advanced OFMT.