A 16-year-old girl was presented to our hospital for neurosurgical treatment because of headache and dizziness. These symptoms developed spontaneously and worsened within 2 weeks without prior trauma. Physical examination and the patient’s medical history were otherwise unremarkable. The initial laboratory testing was normal. Further diagnostic workup revealed that on plain computed tomography (CT), irregular shadows of cystic-solid mixed density were seen at the base of the right middle cranial fossa and the right temporal region, with many liquid planes and scattered punctate calcifications visible within them. The tumor’s boundary was clear, and the maximum cross-sectional area was about 5.4 x 4.4 x 4.0 cm. The lesion had a significant space-occupying effect.

The right temporal lobe and brainstem were compressed, and a large edema shadow was seen in the right temporal lobe, with the brain midline slightly shifted to the left. The surrounding bone of the skull base showed expansive growth, and some bone continuity was interrupted. On T1WI, a circular cystic-solid mixed-signal mass was seen at the base of the right middle cranial fossa and the right temporal region, with a significant space-occupying effect. The tumor edge was smooth and showed a high signal, with hemorrhage, multiple liquid planes, and scattered dotted high signals. On T2WI FLAIR, the tumor showed honeycomb mixed-signal shadows with clear boundaries. Multiple patchy high-signal shadows were seen within the lesion, with irregular high-signal edema zones surrounding them. The enhancement scan revealed significant enhancement of the capsule wall and solid portion. The right temporal lobe, basal ganglia, and brainstem were significantly compressed, and edema was visible in the surrounding brain tissue. The brain midline shifted to the left. MRS: NAA was not shown. CT and magnetic resonance imaging (MRI) suggested that the tumor originated from the right temporal bone and the greater wing of the sphenoid bone and grew intracranially. The tumor was considered a chondroblastoma combined with aneurysmal bone cysts, a giant cell tumor of the bone, or osteosarcoma (Figures 1, 2, 3, 4, 5).^1,2,3

Subsequently, the patient underwent radical surgery at our hospital. Postoperative pathological section: Right sphenoid wing, intermediate-type osteogenic tumor; epithelioid osteoblastoma combined with aneurysmal bone cyst should be considered first.

Immunohistochemistry: CD34 and CD31 vascular endothelial cells+, GFAP-, NSE-, CD68 histiocytes+, EMA-, SMA vascular wall+, SATB2 interstitial cells+, Ki-67 low proliferation, A-inhibin-, S-100-, Syn, STAT6, and P63 histiocytes -/+ (Figure 6).

The tumor was finally considered an epithelioid osteoblastoma combined with an aneurysmal bone cyst originating from the right temporal bone and sphenoid greater wing, as suggested in the preoperative examination.^4,5

Follow-up: One year postoperatively, MRI revealed a patchy high-signal area in the diffusion-weighted imaging sequence and a patchy low-signal area in the ADC sequence from the right temporal region, suggesting a tumor recurrence, but the patient opted for conservative treatment and follow-up (Figure 7).

Ethics Committee Approval: This study was approved by the Ethics Committee of Xiangyang NO.1 People’s Hospital, affiliated to Hubei University of Medicine (no.: 20221825a).

Informed Consent: Informed consent was obtained from the patient’s parents.

Data Sharing Statement: The data that support the findings of this study are available from the corresponding author upon reasonable request.

Author Contributions: Concept- P.A., P.G., G.F.; Design- P.A., P.G., J.L.; Supervision- J.L., G.F.; Fundings- G.F.

Conflict of Interest: No conflict of interest was declared by the authors.

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