Microfilariae of Wuchereria bancrofti in cyst fluid of tumors of the brain: a report of three cases.

Microfilariae of various nematodes, including Loa loa, Dirofilariae, and Onchocerca volvulus, have been identified in the central nervous system (CNS). The CNS, however, is a rare site for the isolation of microfilariae of Wuchereria bancrofti. To the best of our knowledge, the presence of microfilariae of W. bancrofti in tumor cyst fluids or cerebrospinal fluid has not been reported to date. We report three cases in which microfilariae were identified in the cyst fluid of tumors of the brain. Cyst fluid aspirated from space-occupying lesions in the thalamus and C6-D1 spinal segments in a 46-yr-old man and a 35-yr-old man, respectively, showed numerous microfilariae of W. bancrofti, along with fragments of tumor suggestive of glioma. In the third case, in a 12-yr-old boy, the fluid from the space-occupying lesion in the third ventricle showed microfilariae in a necrotic dirty background with a few squames and cholesteral crystals. Histopathologic examination of the tumor showed an anaplastic astrocytoma and a low-grade astrocytoma in the first two cases, respectively, and a craniopharyngioma in the third case. No microfilariae were identified on the histology sections.