Image findings of tendon sheaths affected by diffuse tenosynovial giant cell tumors of the skull base.

OBJECTIVE

This study investigated radiographic images and the differential diagnosis of intracranial diffuse tenosynovial giant cell tumor (D-TGCT) in order to better understand the disease and improve the rate of preoperative diagnosis.

PATIENTS AND

METHODS

Images and clinical data of patients with D-TGCT were retrospectively analyzed. Routine Computer Tomography (CT), routine Magnetic Resonance Imaging (MRI), and contrast-enhanced MRI were performed for nine cases. Susceptibility-weighted imaging (SWI) was also performed for one case.

RESULTS

We reviewed nine patients (6 males and 3 females) aged between 24 and 64 years, with a mean age of 47.33 ± 14.92 years. The most frequent complaints were hearing loss (5/9, 55.6%), pain (4/9, 44%), masticatory symptoms (2/9, 22.2%), and mass (4/9, 44.4%), with a mean duration of 22 ± 21.43 months. All cases were centered on the base of the skull, and showed hyper-density soft-tissue mass with osteolytic bone destruction on CT. The tumor signal mainly showed iso-intensity or hypo-intensity on T1WI compared with that in the brain parenchyma in all patients. On T2WI, nine lesions mainly showed hypo-intensity. Among these nine lesions, three displayed cystic region showing hyper-intensity on T2WI and hypo-intensity on T1WI (Figure 2A, 2B) in the lesion. Nine lesions showed hypo-intensity on DWI sequences. SWI images presented low signal in two cases, showing the "flowering effect". Nine patients showed heterogeneous enhancement, and two patients had meningeal thickening.

CONCLUSIONS

Intracranial D-TGCT is extremely rare, but must be differentiated from other tumors. Osteolytic bone destruction in the area of the skull base with hyper-density soft-tissue mass and hypo-intensity on T2WI images are indicative of D-TGCT.