Clinic—Sphenoid Bone Giant Cell Bone Tumor

Significance Statement

Giant cell tumors (GCT) of the bone are a rare metastasizing bone tumor with a locally aggressive course and mostly benign features. In this article, we present a rare diagnosis of GCT in the sphenoid wing with surrounding bone and soft tissue involvement, as well as a rare atypical age and location. This tumor type should be considered in the differential diagnosis of osteolytic bone lesions involving the epiphysis and, less likely, the metaphysis.

A 12-year-old male patient complained of having a headache and having edema just around his right orbit. Following the anamnesis, a physical examination was conducted. The ophthalmological examination revealed minor edema in the right orbit and axial proptosis in the right temporal region.

On brain-orbital contrast-enhanced magnetic resonance imaging, it originates from the sphenoid wing (orbital posterolateral wall located) on the right, extends to the extraconal area medially, to the intracranial–extracranial area lateral and posteriorly, and to the infratemporal fossa inferiorly, with dimensions of approximately 23 mm × 32 mm × 34 mm at its widest point, and heterogeneous in T1A. The bone lesion was hypointense (Figure 1a-c) and showed heterogeneous contrast enhancement (Figure 1d-f) after IV gadolinium injection, with cystic components showing fluid-fluid leveling in T2A (Figure 2).

Figure 1.

(a-f) Bone lesion originating from the right sphenoid wing is observed in T1W axial, coronal, and sagittal series (all figures are red circle). The lesion extended to the extraconal area medially, to the intracranial–extracranial area laterally and posteriorly, and to the infratemporal fossa inferiorly. A heterogeneous hypointense bone lesion located on the posterolateral wall of the orbit and showing heterogeneous contrast enhancement (d-f red circle) is observed after IV gadolinium injection.

Figure 2.

(a, b) Fluid-fluid levels, which are more common in aneurysmal bone cysts, are seen on T2W axial fat-suppressed images (a, b green arrow).

Because of the described mass, the right orbit is pyroptotic (Figure 1a and d, Figures 2a, 3a). Soft tissue changes in the muscle structures in the right temporal region extending from the extraconal area to the supra-preorbital area with the lateral rectus muscle, showing T2A hyperintense and contrast enhancement (Figure 3), spread medially. Right orbital fissure narrowed; however, the nerve intensity is normal. The retrobulbar fat plane is preserved. Although the right temporal lobe is slightly pressed anteriorly, no pathological signal change has developed.

Figure 3.

(a, b) The lesion has a heterogeneous intensity on axial (a, blue circle) and coronal (b, blue circle) T2W images.

GCT of the bone are aggressive, metastasizing, locally rare, and malignant bone tumors. ¹ GCT makes up 1 in 20 primary bone tumors and 1 in 5 benign bone tumors.^1-4 The highest rate was seen in the age group of 20 to 30 years, with 4/5 patients recorded between the ages of 20 and 50 years.^4,5 Our patient was 12 years old, which is younger than the typical range of predicted ages.

Numerous conditions have been linked to multicentric types, including Paget’s disease of the bone, Gorlin-Goltz syndrome, and Jaffe–Campanacci syndromes.^1,6

The distal femur and proximal tibia are the most commonly affected bones, accounting for roughly 60% to 65% of all cases, followed by the distal radius (10%-12%), the sacrum (4%-9%), and other bone structures in decreasing order.^1,4 One of the unusual locations for a tumor is the sphenoid bone, which is where it is in our situation.

On MR images, bleeding regions, fluid-fluid levels that could indicate alterations such aneurysmal bone cysts, ¹ bone marrow edema surrounding the lesion, extension to soft tissue, and solid components can all be seen. Depending on the amount of solid components, it can be seen in the T1 series with a medium intensity but typically a weak signal. Due to the presence of hemosiderin or fibrosis, it may happen in T2 series when heterogeneous high-signal and low-signal areas coexist. ⁷ Contrast enhancement in solid components may appear to be monitored in contrast-enhanced T1 series, however.

Moving on to the differential diagnoses, there are many other bone lesions that might result in lytic lesions. To name a few, chondroblastoma is more prevalent in developing skeletons and mostly affects the epiphysis. Chondromyxoid myxoma, which may exhibit metaphyseal involvement and have sclerotic lobulated blisters along its margins, must not be overlooked. ⁸ However in individuals with a history of trauma, the diagnosis of giant cell reparative granuloma should also be taken into account. Although fluid-fluid levels can be seen in this image, similar to those seen in giant cell bone tumors, the anamnesis’ description of the complaint’s level of trauma directs us.^9,10 One of the most frequently misunderstood tables is the aneurysmal bone cyst, which can be seen in younger age groups, in pure kinds, where hemorrhagic areas and solid components are not visible, and may emerge with fluid-liquid levels. Non-ossifying fibroma, brown tumor brought on by hyperparathyroidism, enchondroma, hemophilic pseudotumor, chondrosarcoma, metastases, multiple my-eloma, intraosseous ganglion cyst, desmoplastic fibroma, and osteosarcoma are other diagnoses to be kept in mind in addition to those that are most likely to be confused.

If we’re talking about the actual treatment, it involves curettage using local adjuvants like polymethylmethacrylate. ¹¹ One out of every 2 patients treated within 2 years experiences a local recurrence.^1,7 For the treatment of benign metastasizing illnesses, unresectable tumors, patients for whom surgery may result in significant morbidity, as well as locally advanced tumors, neoadjuvant therapy using denosumab has been used. ¹