Primary leptomeningeal melanomatosis is a rare and aggressive variant of primary central nervous system melanoma. Diagnosis is often challenging due to nonspecific radiologic features. We hereby report the 18 F-FDG PET/CT and MRI findings in a case of primary leptomeningeal melanomatosis in a 47-year-old woman with a previously unidentified diastematomyelia. Spinal MRI showed diffuse abnormal signal. 18 F-FDG PET/CT showed hypermetabolism most notably in the lumbar and caudal portion of the spinal cord, which was helpful to identify an appropriate site for biopsy.
Wang et al. (Tue,) studied this question.