Pearls and Pitfalls in Interpretation of Ga-68-DOTATOC PET Imaging

DOTA-D-Phe1-Tyr3-octreotide labeled with 68Ga (68Ga-DOTATOC) is the commonly used PET tracer for imaging meningioma because of its high affinity to somatostatin receptor subtype 2 (SSTR2) and an established imaging modality for planning radiation and radionuclide therapy. However, SSTR2 is not an exclusive marker for meningioma, and not all meningiomas express high levels of SSTR2. The SSTR2 expression has been reported in other intracranial tumors, for example, glioma, pituitary adenoma, medullablastoma, primitive neuroectodermal tumors, and hemangioblastoma leading to a significant risk of misinterpretation of PET/CT findings. We present 2 cases with similar 68Ga-DOTATOC uptakes in 2 distinct etiologies, for example, cerebral lymphoma and meningioma.