Fused 18F-Choline PET/MRI: A potential non-invasive biomarker imaging tool in cerebral vasculitis

Abstract

Primary CNS vasculitis is an inflammatory brain disease commonly misdiagnosed affecting the medium and small vessels of the CNS. Due to its broad and non-specific clinical and radiological manifestations; Its diagnosis remains challenging. New diagnostic tools and biomarkers which increase specificity and facilitate the diagnosis for patients with suspected vasculitis are highly desirable to enable physicians to start therapy that can alter its potential aggressive course like immunosuppressant. This case report highlights the potential role of 18 F-choline PET/MRI as a novel imaging tool that might help in the right clinical scenario in the diagnosis of this disease. Furthermore, it speculates on its secondary role in monitoring the response to immunosuppressant therapy.

18F-FDG Brain PET/MRI in Granulomatous Primary Angiitis of the Central Nervous System

“…1 Primary CNS angiitis is rare with an annual incidence rate of 2.4 cases per million and a median age of 50 years at presentation. 2 Previous reports in the literature have shown an association with Sjögren syndrome, herpes zoster, HIV, and Hodgkin lymphoma, none of which were present in our patient. 3 The diagnosis of primary CNS angiitis is challenging given the varied and nonspecific clinical presentation, and the large array of potential differential diagnoses, such as reversible cerebral vasoconstriction syndrome.…”

“…CNS vasculitis is classified either as primary angiitis, when the findings are confined to the CNS, or secondary in cases with evidence of a systemic inflammatory process 1 . Primary CNS angiitis is rare with an annual incidence rate of 2.4 cases per million and a median age of 50 years at presentation 2 . Previous reports in the literature have shown an association with Sjögren syndrome, herpes zoster, HIV, and Hodgkin lymphoma, none of which were present in our patient 3 .…”

The other immuno-PET: Metabolic tracers in evaluation of immune responses to immune checkpoint inhibitor therapy for solid tumors

“…An increased accumulation of [ 18 F]-Fluorocholine, a promising agent that reflects upregulation of cell membrane synthesis, has been observed in the non-metastatic mediastinal, axillary, inguinal and cervical lymph nodes in about 6.3% of prostate cancer patients ( 62 , 63 ). Considering the uptake in other inflammatory processes involving T lymphocytes and activated macrophages ( 64 ), as well as the recent report that suggests a close relationship between PD-L1 immune checkpoint, choline metabolism and inflammation ( 65 ), it would be interesting to study whether the lymphoid tissue uptake of [ 18 F]-Fluorocholine or other imaging agent that evaluates lipid metabolism might provide useful information on immune response to ICI therapy.…”