18F-FDG PET/CT Findings of Leptomeningeal Metastasis in Nasopharyngeal Carcinoma

Abstract

Nasopharyngeal carcinoma (NC) is an epithelial tumor with distinctive prevalence in East and Southeast Asia. Most patients with NC only experience regional metastasis. In cases of distant metastasis, prognosis is grim. Leptomeningeal spread of the disease is a rare occurrence, which is sparsely described in the literature. We present a case of a 33-year-old man with a history of high-grade NC with leptomeningeal metastasis. Initial MRI lumbar spine demonstrated subtle findings consistent with leptomeningeal disease. These findings are easily discernible on 18F-FDG PET/CT.

Case report: Leptomeningeal metastasis of advanced nasopharyngeal carcinoma treated with chemoimmunotherapy

“…Recently, a case demonstrated the utility of PET/CT in the diagnosis of LM. 12 Cytological demonstration of malignant cells in the CSF is the gold standard for the diagnosis of LM. CSF cytology is positive in 50% to 60% of patients while the rate can be improved to 85% with repeat cytologic examinations.…”

Leptomeningeal Metastasis From Neuroblastoma Revealed by 123I-MIBG SPECT/CT

“…Cerebral spine fluid cytology, which is considered as the standard for the disease detection, is invasive and is not always high in sensitivity. Different nuclear medicine methods have been used in the diagnosis of leptomeningeal metastasis, including 18 F-FDG PET/CT, 8–10 18 F-DOPA PET/MRI, 11 and 68 Ga-DOTATATE PET/CT 12 . MIBG scintigraphy is a relatively sensitive modality for the detection of neuroblastoma 13,14 .…”

Solitary Dural Metastasis From Neuroblastoma Detected by 123I-MIBG SPECT/CT

“…Several nuclear medicine tracers can have elevated accumulation in dural metastasis, including 18 F-FDG, 3 somatostatin analogs, 5,7 18 F-florapronol, 8 and Pittsburgh compound B 9 . Similarly, leptomeningeal metastasis can also lead to increased activity of many nuclear medicine tracers, which include 18 F-FDG, 10,11 123 I-MIBG, 12 18 F-NOTATATE, 13 18 F-FES, 14 68 Ga-DOTATATE, 15 and 68 Ga-FAPI 16 …”