Hybrid Positron Emission Tomography and Magnetic Resonance Imaging Guided Microsurgical Management of Glial Tumors: Case Series and Review of the Literature

Abstract

In this case series, we aimed to report our clinical experience with hybrid positron emission tomography (PET) and magnetic resonance imaging (MRI) navigation in the management of recurrent glial brain tumors. Consecutive recurrent neuroglial brain tumor patients who underwent PET/MRI at preoperative or intraoperative periods were included, whereas patients with non-glial intracranial tumors including metastasis, lymphoma and meningioma were excluded from the study. A total of eight patients (mean age 50.1 ± 11.0 years) with suspicion of recurrent glioma tumor were evaluated. Gross total tumor resection of the PET/MRI-positive area was achieved in seven patients, whereas one patient was diagnosed with radiation necrosis, and surgery was avoided. All patients survived at 1-year follow-up. Five (71.4%) of the recurrent patients remained free of recurrence for the entire follow-up period. Two patients with glioblastoma had tumor recurrence at the postoperative sixth and eighth months. According to our results, hybrid PET/MRI provides reliable and accurate information to distinguish recurrent glial tumor from radiation necrosis. With the help of this differential diagnosis, hybrid imaging may provide the gross total resection of recurrent tumors without harming eloquent brain areas.

Keywords: hybrid imaging; magnetic resonance imaging; positron emission tomography; radiation necrosis; recurrent glial tumor.

Figure 1

Case 3. Magnetic resonance imaging (MRI) (A) revealed an enhancing mass lesion (black asterisk) in the left frontoparietal lobe. A hybrid PET/MRI image (B) showed a hot spot (white asterisk), suggesting recurrent glioma.

Figure 2

Case 5. T1-weighted magnetic resonance imaging (MRI) (A) revealed heterogenous contrasting lesions (arrowheads). Positron emission tomography/MRI images (B) showed focal hot spots (arrows) within the previously operated area (asterisk) as well as in a different area.