Fibromyxoma of nasal fossa: features on magnetic resonance imaging

Clinical Presentation

A 50-year-old female patient presented with a bi-lobed, bell-shaped, smooth, mucosalized mass involving the nose. Thin-section pre- and postcontrast magnetic resonance imaging (MRI) performed through the sinonasal cavity showed a midline, bi-lobed mass involving the floor of the nasal cavity. The superior aspect involves the nasal septum and extends to the inferior portion of the bilateral middle turbinate and anterior hard palate. Regressive remodeling of the medial wall of both maxillary sinuses and erosion of the anterior portion of the right hard palate, the right lateral nasopalatine canal, and maxillary alveolus were noted. Superficial muscles of facial expression were evident. The mass was intermediate signal on T1, and homogeneously enhanced with contrast. It had a heterogeneous T2 signal.

Differential Diagnosis

Differential diagnoses included minor salivary gland neoplasms, sarcomas, osteosarcoma/chondrosarcoma, hematopoietic lesion (lymphoma), or neoplasm of histiocytic origin. Although squamous cell carcinoma is the most common neoplasm to involve the sinonasal region, the imaging features and submucosal appearance make it less likely.

Diagnosis and Management

Histopathologic examination revealed a fibromyxoma. The lesion was resected out. Due to the high recurrence rate of >25%, a minimum 5-year follow-up is required.

Conclusion

Fibromyxomas of the jaws are rare with an incidence of approximately 0.07 new cases per million people per year. Anterior maxilla is rarely affected. The location, aggressive behavior involving the nasal fossae and maxillary sinuses, and high recurrence rate underscores the complexity of diagnosis. Radiographic examination, including MRI, plays a crucial role in the differential diagnosis and treatment planning. With scant reports in the literature on MRI findings of fibromyxoma of the nasal fossa, this report, including a review of the literature, expounds on the variations in clinical and radiographic features of this lesion.