5-ALA−Induced Fluorescence in Leptomeningeal Dissemination of Spinal Malignant Glioma

Background 5-Aminolevulinic acid (5-ALA)-fluorescence-guided resection of malignant glioma is well established in many neuro-oncology departments. In addition, the use of 5-ALA has been reported for cerebral metastases, meningioma, and spinal tumors. We report a case of a patient with a leptomeningeal spread of a K27M-mutated spinal anaplastic astrocytoma (World Health Organization° [WHO] III), which was detected by its faint 5-ALA-induced fluorescence. Case Description A 26-year-old female patient with an incomplete resection of a spinal astrocytoma (WHO II) at Th1-Th3 was treated with adjuvant combined radiotherapy/chemotherapy. After 4 years the patient suffered from a progressive paraplegia. Magnetic resonance imaging of the central nervous system showed no local progression of the spinal astrocytoma but an extensive disseminated leptomeningeal tumor formation. The cerebrospinal fluid of the patient obtained by lumbar puncture showed no indication of malignant cells in the cytopathologic examination. An open biopsy with preoperative administered 5-ALA with excision of the sensory nerve root from the cauda equina was performed. The biopsy showed a clearly light pink 5-ALA-induced fluorescence. The histopathologic examination confirmed a leptomeningeal spread of a K27M-mutated anaplastic astrocytoma (WHO° III) without R132H-IDH1 mutation. Conclusions Previous application of 5-ALA might intraoperatively help to visualize and identify leptomeningeal spread.