Paraganglioma of the filum terminale: review and report of the first case analyzed by CGH.

OBJECTIVE: As a rare tumor paraganglioma of the filum terminale is of diagnostic challenge. A thorough review of all published cases most often reveals a benign course if complete surgically resection is achieved. We report on the first molecular cytogenetic analyses performed on filum termiale paragangliomas. CLINICAL PRESENTATION: A 52-year-old man suffered from low back pain for many years that gradually worsened and was aggravated by sitting and bending. The pain radiated dorsally into both legs. Magnetic resonance imaging (MRI) with and without Gd-DTPA revealed a 12 mm sized, intradural oval mass at the level of L3 with slightly increased T2-signal and a rim of low signal on T2-weighted sequences. The tumor enhanced remarkably after Gd-DTPA. INTERVENTION: The patient underwent a left sided hemilaminectomy of L3. Durotomy revealed a well-delineated, firm and highly vascularized reddish tumor. The proximal terminal filum entered the tumor at the proximal pole and exited its distal pole. Coagulation and dissection of the terminal filum allowed in toto removal of the tumor. DNA was isolated from the formalin-fixed and paraffin-embedded specimen. The tumor was analyzed by comparative genomic hybridization, providing a normal DNA profile without any chromosomal copy number changes. CONCLUSION: The origin of paragangliomas of the CNS and especially of the filum terminale is still unclear. If no complete surgical resection can be achieved, molecular cytogenetic analysis is of additional value to prognostification of paragangliomas of the filum terminale.