Presentation
Patient presents in the emergency room due to entropy of the right eye of 3 weeks of evolution, with simultaneous decrease in visual acuity; objectively presents with ptosis of the right eye and diplopia.
Patient Data
Extensive expansive/infiltrative lesion centered on the sphenoid sinus, extending to the nasal cavities, with heterogeneous spontaneous density and enhancement, with marked bone erosion. Infiltrates and destroys the sphenoid bone, clinoid apophyses, sella turcica, dorsi sellar and clivus, as well as the great wing and pterygoid apophyses on the right. Also invades the cavernous sinuses and the orbital apexes, mainly through the optic nerve channels and contacts the internal carotid arteries, without narrowing them.
Biopsy of the lesion was performed a few days after the first CT scan, proving an ossifying fibromyxoid tumor.
Conservative treatment was decided (surgical treatment was not an option for this extensive lesion) and an imaging study was repeated after one year to assess the extent of the lesion.
Large osteodestructive tumoral lesion centered on the sphenoethmoidal complex, with clear increased dimensions and greater involvement of adjacent structures, including intracranial compartment.
Its characteristics to the CT scan are similar, with heterogeneous density and enhancement, while on MRI the tumor has a heterogeneous signal, globally T1 hypointense and T2, T2/STIR and T2/ FLAIR hyperintense; it enhances diffusely and heterogeneously, with multiple intra-lesional cystic components.
Tumor involvement and its relationship to adjacent structures can be better delineated with MRI, and may be summarized as follows:
- Anteriorly it extends to the nasal cavity, the right maxillary sinus and the left ethmoidal infundibulum, with obliteration of the ostiomeatal units, the frontal recesses and the ethmoid recesses and subsequent sinusitis in the non-infiltrated sinuses.
- Laterally it goes beyond the limits of the sphenoid sinus, insinuating into the masticatory space on the left, while on the right it infiltrates the same space in a more diffuse way, involving the pterygoid muscles; there is also bone destruction of the middle cranial fossa, more exuberant on the right, where there is an intracranial extra-axial tumor component that elevates/distorts the anterior temporal pole
- Superomedially it results in bone destruction of the anterior cranial floor with intracranial extra-axial expression that deforms the frontobasal brain parenchyma
- Superolaterally the tumor destroys the most posterior portion of the papyraceous laminae, with intra-orbital extra-conical expression on the right, but no intra-orbital expression on the left.
- Posteriorly there is important erosion of the bone structures of the skull base, with destruction of the optic nerve channels, involving the respective atrophied nerves; there is bilateral invasion of cavernous sinuses and sella turcida, with intrasellar expression and consequent elevation of the pituitary gland, but no suprasellar cistern expression; the optic chiasm is not contacted and has a normal topography, although it is clearly atrophic; there is also partial erosion of the carotid canals, with the internal carotid arteries being surrounded in distal petrous and cavernous segments, but with normal caliber.
- At the most posterior limit of the skull base, there is destruction of the petrous apexes and clivus, with the tumoral lesion being posteriorly limited by the dura (but not exceeding it) and resulting in a reduction in the amplitude of the pre-protuberant cistern and contacting the basilar artery.
Case Discussion
Ossifying fibromyxoid tumors are rare soft tissue tumors of uncertain histogenesis, generally affecting middle-aged adults. They predominantly arise in the subcutaneous tissue of extremities or trunk, and rarely in the head and neck region (in that case generally emerging from the sphenoid and/or ethmoid sinuses). Despite being considered benign neoplastic lesions, they are locally aggressive, destructing adjacent bony margins.
When in the latter location, nasal endoscopic surgery can be an approach (usually when of small dimensions), and open surgery may be an option in some cases. In our case, due to the large size of the lesion and diffuse extension to the adjacent structures, surgical treatment would not be viable, so it was opted for the best medical treatment (with radiotherapy - justifying the atrophy of the optic pathways).
It is extremely important to recognize this type of neoplastic lesion, which rarely affects the paranasal sinuses, in order to avoid potential misdiagnosis and to allow correct therapeutic management - complete surgical excision and close follow-up for recurrence surveillance.