Cognitive Decline following Radiotherapy of Head and Neck Cancer: Systematic Review and Meta-Analysis of MRI Correlates

Radiotherapy for head and neck cancers exposes small parts of the brain to radiation, resulting in radiation-induced changes in cerebral tissue. In this review, we determine the correlation between cognitive deterioration in patients with head and neck cancer after radiotherapy and magnetic resonance imaging (MRI) changes. Systematic searches were performed in PubMed, Scopus, and Cochrane databases in February 2021. Studies of head and neck cancer patients treated with radiotherapy and periodical cognitive and MRI assessments were included. Meta-analysis was performed to analyse the correlation of Montreal Cognitive Assessment (MoCA) scores to MRI structural and functional changes. Seven studies with a total of 404 subjects (irradiated head and neck patients, n = 344; healthy control, n = 60) were included. Most studies showed the significance of MRI in detecting microstructural and functional changes in association with neurocognitive function. The changes were seen in various brain areas, predominantly the temporal region, which also shows dose dependency (6/7 studies). An effect size (r = 0.43, p < 0.001) was reported on the correlation of MoCA scores to MRI structural and functional changes with significant correlations shown among patients treated with head and neck radiotherapy. However, the effect size appears modest.

The first two cases of posterior reversible encephalopathy syndrome (PRES) secondary to conventional transcatheter arterial chemoembolization of hepatocellular carcinoma

Background Posterior reversible encephalopathy syndrome (PRES) is a very rare complication secondary to transcatheter arterial chemoembolization (TACE). Only two patients with liver metastasis have been reported. We report for the first time two cases of hepatocellular carcinoma (HCC) patients occurred PRES secondary toTACE. Case presentation The two patients with HCC developed headache, epilepsy, expressive aphasia, visual impairment and loss of consciousness, 11 and 3 h after conventional TACE (c-TACE) surgery. One patient experienced raised blood pressure during and after TACE, accompanied by a significant elevated creatinine. The magnetic resonance imaging (MRI) of the two patients showed multiple abnormal signals in the brain, mainly located in the white matter region. Combined with the clinical symptoms and MRI findings, PRES was diagnosed. Their symptoms and MRI changes improved significantly in the next two weeks. Conclusion The PRES in this report is chemoembolization-associated syndrome, which might be related to the use of chemotherapy agents during TACE. And if neurological symptoms occur after TACE, patients should be closely monitored to exclude PRES.

NIMG-27. REGORAFENIB RESPONSE ASSESSMENT USING FET PET IN PATIENTS WITH PROGRESSIVE GLIOMA

BACKGROUND The REGOMA phase 2 trial showed an encouraging overall survival benefit of the multikinase inhibitor regorafenib in glioblastoma patients at first progression. We used O-(2-[18F]fluoroethyl)-L-tyrosine (FET) PET for the early assessment of response to regorafenib in patients with progressive glioma in an advanced disease stage. METHODS Thirty patients with progressive glioma were treated according to the REGOMA trial and prospectively followed. FET PET and MRI were performed at baseline and after the second cycle of regorafenib. Static PET parameters such as maximum and mean tumor-to-brain ratios (TBRmax, TBRmean) and metabolic tumor volumes (MTV) were calculated. Threshold values of FET PET parameters to predict a response were established by ROC analyses using an overall survival of ≥ 6 months as reference. The predictive value of FET PET parameters and their changes concerning overall survival was subsequently evaluated using the Kaplan-Meier test. MRI changes were evaluated according to the RANO criteria. RESULTS Up to now, 18 of 30 patients (glioblastoma, 83%; age range, 24-71 years) were eligible for data evaluation. The median number of tumor relapses before regorafenib was 2 (range, 1-4). During regorafenib (median cycles, 4; range, 2-9 cycles), CTCAE grade 3 or 4 side effects occurred in 56% and 11%, respectively. The median overall survival was 6 months (range, 3-18 months). After two cycles of regorafenib, a TBRmean reduction of 13% predicted a significantly longer overall survival (12 vs. 6 months; P=0.034). In contrast, MRI changes evaluated according to RANO criteria (i.e., Stable Disease or Partial Response vs. Progressive Disease) were not predictive (11 vs. 8 months; P=0.644). CONCLUSION Data suggest that amino acid PET using the tracer FET may be clinically valuable for identifying responders to regorafenib early after treatment initiation.