Incidental Findings of a Vestibular Schwannoma on 18F-Choline PET/CT

18F-Choline PET Detected the Third Ventricle Craniopharyngioma

ABSTRACT

Craniopharyngiomas are rare tumors of low histological malignancy (World Health Organization grade I) in the sellar and suprasellar region of the brain. We report a case of the third ventricular craniopharyngioma detected using 18F-choline PET/CT in a 43-year-old man. MRI of the brain revealed an intense gadolinium enhancement focus in the same area. Histology revealed characteristics of papillary craniopharyngioma. Our findings suggest that craniopharyngioma should be included in the differential diagnosis of 18F-choline-avid brain lesions.

Intracavernous Schwannoma Characterized With 18F-FDG, 68Ga-DOTATOC, and 18F-Choline PET

ABSTRACT

We report the case of a 75-year-old man with history of prostate cancer whose left intracavernous lesion was successfully characterized by 3 PETs performed successively with different tracers. This poorly characterized tumor was initially discovered on an MRI conducted to investigate an acute diplopia and slowly growing during follow-up. On 18F-FDG PET, the lesion showed no significant uptake, and no extracranial lesion was found nor did it have increased 68Ga-DOTATOC uptake. Finally, this tumor displayed a high 18F-choline uptake, and no extracranial lesion was revealed with this tracer. The diagnosis of schwannoma without malignancy criterion was proven by biopsy.