J Neurosurg 73:459-461, 1990
Giant gangliocytic paraganglioma of the filum terminale Case report MICHEL DJINDJIAN, M.D., PATRICK AYACHE, M.D., lhERnE BRUGII~2RES~M.D., DENIS MALAPERT, M.D., MARIELLE BAUDRIMONT, M.D., AND JACQUES POIRIER, M.D. Departments of Neurosurgery, Neuroradiotogy, Neurology, and Pathology (Neuropathology), H6pital Henri Mondor. Crbteil, and Department of Pathology, Saint-Antoine Hospital, Paris, France u- The clinical and pathological features of a giant cauda equina paraganglioma arising from the intradural filum terminale is described. Scattered mature large neurons characterized the tumor as a gangliocytic paraganglioma. Histologically, these neoplasms have considerable similarity with ependymoma and the diagnosis can be easily missed unless special techniques are employed. KEY WORDS ultrastructure
~
paraganglioma
9 cauda equina
E
XTRA-ADRENAL paragangliomas, also known as 'chemodectomas, occur most commonly in the neck and head region (principally from the carotid bodies or the gtomus jugulare). They are found less frequently in the mediastinum or in the retroperitoneum and rarely in other locations such as the lungs, duodenum, orbit, larynx, or urinary bladder? Few cases have been described within the spinal canal, and all of these have been in the cauda equina region? This report concerns an additional case of paraganglioma of this latter region and emphasizes its presentation as a giant tumor of the cauda equina. This case arose from the intradural filum terminale, and was identified as gangliocytic by histological and ultrastructural studies.
Case Report This 36-year-old man was admitted to the emergency department in December, 1986, because of sudden paraplegia following sacral infiltration of medication for treatment of a low-back pain. Metrizamide myetography with lateral cervical infusion and computerized tomography showed a complete block at the L-2 level with moderate vascular filling defects suggestive of an ependymoma of the cauda equina. Examination on admission revealed severe paraplegia: motor strength was 2/5 in the quadriceps and 0/5 in the distal extremities. Proprioception was absent in both legs and there
J. Neurosurg. / Volume 73 / September, 1990
9 ilium terminale
9 spinal tumor
was an L-3 level of sensation to pinprick. Deep-tendon reflexes were absent. Incontinence of urine and feces was noted. Spinal angiography was not undertaken because of the emergency clinical status of the patient. Lumbar laminectomy was performed from L-1 to L-5. A well-delimited intradural tumor was exposed extending from 2 cm below the conus medullaris to the L-5 level and attached to the filum terminale. Tortuous vessels were seen at both extremities of the tumor along the filum: a large ascending vein and a small descending artery arose at the upper pole and a small vein was associated with the intrasacral part of the filum at the distal pole. With the aid of the operating microscope and Cavitron ultrasonic surgical aspirator, the tumor was excised completely. Postoperative recovery was uneventful; however, 15 months later the patient's neurological functions had returned to a subnormal state. Routine histological study of the tumor showed irregular islands and lobules of small round-to-polyhedral cells in a vascular stroma. In several areas, large mature neurons were dispersed through the tumor. Definite ganglionic differentiation and cells lying between paraganglioma cells and well-differentiated neurons were observed, especially by examination of the semithin sections stained by the silver technique of Rosenquist (Fig. 1A). Electron microscopic examination showed numerous intracytoplasmic dense-core vesicles consistent with neurosecretory granules in most of the tumor 459
M. Djindjian, et al.
FIG. 1. A: Photomicrograph of a semithin section stained by the silver technique of Rosenquist showing large neurons (single arrow) and paraganglionic cells (double arrow), x 100. B: Electron micrograph of the paraganglionic tumor cells showing dense-core vesicles, rough endoplasmic reticulum, and Golgi complex, x 5400. C: Electron micrograph showing cytoplasmic dense-core vesicles (arrows) in intermediate paraganglioma tumor cells. • 6300. D: Electron micrograph showing cytoplasmic dense-core vesicles in neuronal processes (arrows) containing mitochondria and neurofilaments, x 10,000. cells (Fig. 1B and C), as well as the neurons (Fig. 1D). These histological and ultrastructural features allowed the precise diagnosis of gangliocytic paraganglioma.
Discussion In their recent review, Sonneland, et al., 5 found a total of 53 published cases of paragangliomas of the 460
cauda equina region. Four additional cases have been reported so far. 1'2'4Among these 57 cases, only 14 were of the gangliocytic variety. In the present case, a gangliocytic tumor, the size of the mass (8 x 3 x 3 cm, one of the largest so far reported) allowed it to be considered as a giant tumor of the cauda equina region. The origin of the t u m o r from the filum terminale was clearly demonstrated during the surgical intervention,
J. Neurosurg. / Volume 73/September, 1990
Gangliocytic paraganglioma of the filum terminale and no attachment to a nerve root was found. As seems to be the rule for paragangliomas of this location, there was clinically no sign of any catecholamine syndrome. The diagnosis of paragangliomas and the definition of their subtype (whether nongangliocytic, gangliocytic, or oncocytic) is always made postoperatively from the histological study of the tumor. The frequent instances of histological misdiagnosis as an ependymoma or ependymoblastoma must be kept in mind, because the prognosis of these tumors is quite different. Paragangliomas of the cauda equina region are slow-growing, benign, encapsulated tumors that may be cured by surgery alone. It seems that adjuvant radiotherapy should be reserved for nonencapsulated or incompletely excised lesions? References
1. Anderson JR, Gullan RW: Paragangliomas of the cauda equina: a case report. J Neurol Neurosurg Psychiatry 50: 100-103, 1987
J. Neurosurg. / Volume 73/September, 1990
2. Gaffney EF, Doorly T, Dinn J J: Aggressive oncocytic neuroendocrine tumour ("oncocytic paraganglioma") of the cauda equina. Histopathology 10:311-319, 1986 3. Glenner GG, Grimley PM: Tumors of the extra-adrenal paraganglion system (including chemoreceptors), in: Atlas of Tumor Pathology, Series 2, Fascicle 9. Washington, DC: Armed Forces Institute of Pathology, 1974, pp 55-80 4. Ironside JW, Royds JA, Taylor CB, et al: Paraganglioma of the cauda equina: a histological, ultrastructural and immunocytochemical study of two cases with a review of the literature. J Pathol 145:195-201, 1985 5. Sonneland PRL, Scheithauer BW, LeChago J, et al: Paraganglioma of the cauda equina region. Clinicopathological study of 31 cases with special reference to immunocytology and ultrastructure. Cancer 58:1720-1735, 1986 Manuscript received March 30, 1989. Accepted in final form February 8, 1990. Address for Dr. Baudrimont: Department of Pathology, Saint-Antoine Hospital, Paris, France. Address reprint requests to." Michel Djindjian, M.D., Service de Neurochirurgie, H6pital Henri Mondor, 94000 Cr6teil, France.
461
Giant gangliocytic paraganglioma of the filum terminale Case report MICHEL DJINDJIAN, M.D., PATRICK AYACHE, M.D., lhERnE BRUGII~2RES~M.D., DENIS MALAPERT, M.D., MARIELLE BAUDRIMONT, M.D., AND JACQUES POIRIER, M.D. Departments of Neurosurgery, Neuroradiotogy, Neurology, and Pathology (Neuropathology), H6pital Henri Mondor. Crbteil, and Department of Pathology, Saint-Antoine Hospital, Paris, France u- The clinical and pathological features of a giant cauda equina paraganglioma arising from the intradural filum terminale is described. Scattered mature large neurons characterized the tumor as a gangliocytic paraganglioma. Histologically, these neoplasms have considerable similarity with ependymoma and the diagnosis can be easily missed unless special techniques are employed. KEY WORDS ultrastructure
~
paraganglioma
9 cauda equina
E
XTRA-ADRENAL paragangliomas, also known as 'chemodectomas, occur most commonly in the neck and head region (principally from the carotid bodies or the gtomus jugulare). They are found less frequently in the mediastinum or in the retroperitoneum and rarely in other locations such as the lungs, duodenum, orbit, larynx, or urinary bladder? Few cases have been described within the spinal canal, and all of these have been in the cauda equina region? This report concerns an additional case of paraganglioma of this latter region and emphasizes its presentation as a giant tumor of the cauda equina. This case arose from the intradural filum terminale, and was identified as gangliocytic by histological and ultrastructural studies.
Case Report This 36-year-old man was admitted to the emergency department in December, 1986, because of sudden paraplegia following sacral infiltration of medication for treatment of a low-back pain. Metrizamide myetography with lateral cervical infusion and computerized tomography showed a complete block at the L-2 level with moderate vascular filling defects suggestive of an ependymoma of the cauda equina. Examination on admission revealed severe paraplegia: motor strength was 2/5 in the quadriceps and 0/5 in the distal extremities. Proprioception was absent in both legs and there
J. Neurosurg. / Volume 73 / September, 1990
9 ilium terminale
9 spinal tumor
was an L-3 level of sensation to pinprick. Deep-tendon reflexes were absent. Incontinence of urine and feces was noted. Spinal angiography was not undertaken because of the emergency clinical status of the patient. Lumbar laminectomy was performed from L-1 to L-5. A well-delimited intradural tumor was exposed extending from 2 cm below the conus medullaris to the L-5 level and attached to the filum terminale. Tortuous vessels were seen at both extremities of the tumor along the filum: a large ascending vein and a small descending artery arose at the upper pole and a small vein was associated with the intrasacral part of the filum at the distal pole. With the aid of the operating microscope and Cavitron ultrasonic surgical aspirator, the tumor was excised completely. Postoperative recovery was uneventful; however, 15 months later the patient's neurological functions had returned to a subnormal state. Routine histological study of the tumor showed irregular islands and lobules of small round-to-polyhedral cells in a vascular stroma. In several areas, large mature neurons were dispersed through the tumor. Definite ganglionic differentiation and cells lying between paraganglioma cells and well-differentiated neurons were observed, especially by examination of the semithin sections stained by the silver technique of Rosenquist (Fig. 1A). Electron microscopic examination showed numerous intracytoplasmic dense-core vesicles consistent with neurosecretory granules in most of the tumor 459
M. Djindjian, et al.
FIG. 1. A: Photomicrograph of a semithin section stained by the silver technique of Rosenquist showing large neurons (single arrow) and paraganglionic cells (double arrow), x 100. B: Electron micrograph of the paraganglionic tumor cells showing dense-core vesicles, rough endoplasmic reticulum, and Golgi complex, x 5400. C: Electron micrograph showing cytoplasmic dense-core vesicles (arrows) in intermediate paraganglioma tumor cells. • 6300. D: Electron micrograph showing cytoplasmic dense-core vesicles in neuronal processes (arrows) containing mitochondria and neurofilaments, x 10,000. cells (Fig. 1B and C), as well as the neurons (Fig. 1D). These histological and ultrastructural features allowed the precise diagnosis of gangliocytic paraganglioma.
Discussion In their recent review, Sonneland, et al., 5 found a total of 53 published cases of paragangliomas of the 460
cauda equina region. Four additional cases have been reported so far. 1'2'4Among these 57 cases, only 14 were of the gangliocytic variety. In the present case, a gangliocytic tumor, the size of the mass (8 x 3 x 3 cm, one of the largest so far reported) allowed it to be considered as a giant tumor of the cauda equina region. The origin of the t u m o r from the filum terminale was clearly demonstrated during the surgical intervention,
J. Neurosurg. / Volume 73/September, 1990
Gangliocytic paraganglioma of the filum terminale and no attachment to a nerve root was found. As seems to be the rule for paragangliomas of this location, there was clinically no sign of any catecholamine syndrome. The diagnosis of paragangliomas and the definition of their subtype (whether nongangliocytic, gangliocytic, or oncocytic) is always made postoperatively from the histological study of the tumor. The frequent instances of histological misdiagnosis as an ependymoma or ependymoblastoma must be kept in mind, because the prognosis of these tumors is quite different. Paragangliomas of the cauda equina region are slow-growing, benign, encapsulated tumors that may be cured by surgery alone. It seems that adjuvant radiotherapy should be reserved for nonencapsulated or incompletely excised lesions? References
1. Anderson JR, Gullan RW: Paragangliomas of the cauda equina: a case report. J Neurol Neurosurg Psychiatry 50: 100-103, 1987
J. Neurosurg. / Volume 73/September, 1990
2. Gaffney EF, Doorly T, Dinn J J: Aggressive oncocytic neuroendocrine tumour ("oncocytic paraganglioma") of the cauda equina. Histopathology 10:311-319, 1986 3. Glenner GG, Grimley PM: Tumors of the extra-adrenal paraganglion system (including chemoreceptors), in: Atlas of Tumor Pathology, Series 2, Fascicle 9. Washington, DC: Armed Forces Institute of Pathology, 1974, pp 55-80 4. Ironside JW, Royds JA, Taylor CB, et al: Paraganglioma of the cauda equina: a histological, ultrastructural and immunocytochemical study of two cases with a review of the literature. J Pathol 145:195-201, 1985 5. Sonneland PRL, Scheithauer BW, LeChago J, et al: Paraganglioma of the cauda equina region. Clinicopathological study of 31 cases with special reference to immunocytology and ultrastructure. Cancer 58:1720-1735, 1986 Manuscript received March 30, 1989. Accepted in final form February 8, 1990. Address for Dr. Baudrimont: Department of Pathology, Saint-Antoine Hospital, Paris, France. Address reprint requests to." Michel Djindjian, M.D., Service de Neurochirurgie, H6pital Henri Mondor, 94000 Cr6teil, France.
461
