Paraganglioma of the cauda equina region: Clinicopathologic study of 31 cases with special reference to immunocytology and infrastructure

Abstract

Thirty-one paragangliomas of the cauda equina region were studied (18 men and 13 women, ages 30-71 years [mean, 51 years]). Symptoms (1 day to 15 years in duration; mean, 48 months) included low back pain (87%), sensory/motor deficits (35%), urinary/fecal incontinence (13%), and paraplegia (6%). All patients studied had some myelographic block. Cerebrospinal fluid protein level ranged from 56 to 7000 mg/dl (mean, 1109 mg/dl). Most tumors were limited to the filum terminale, although one also involved the conus medullaris and two clearly arose from a caudal nerve root. All but one were entirely intradural. The tumor was totally excised in 26 cases; these patients remain disease-free. Of three patients whose tumors were excised subtotally, two received radiotherapy; the one non-radiated patient died of tumor-related complications. No autopsy was performed. One partially encapsulated tumor that had been subjected to biopsy and irradiation presented 1 year later with osseous invasion and retroperitoneal extension; 20 years after subtotal excision, this patient is alive but paraplegic. Morphologically, all tumors resembled paraganglioma at other sites. Cytologic atypia and mitotic activity generally were absent to mild. Fourteen (45%) cases showed ganglionic differentiation. All tumors tested were immunoreactive for neuron-specific enolase and neurofilament protein, and most showed somatostatin or serotonin reactivity. S-100 protein immunoreactivity was noted in sustentacular cells and, to a lesser extent, within chief cells and neurons. The authors conclude that paragangliomas are largely benign and encapsulated and respond to simple resection. When surgically feasible, gross total removal should be the goal of surgery. When subtotal resection is necessary or when local invasion leaves a question as to completeness of tumor removal, irradiation seems mandatory although far from guaranteeing prevention of recurrence. Biopsy alone is undesirable.

Cauda equina paraganglioma with ependymoma-like histology: a case presentation

“…The latter condition is quite rare and to our knowledge, only a few cases of PGs with ependymoma-like histology have been reported to date (17,19,20). This rare entity should be kept in mind to avoid any misdiagnosis of ependymoma which is known to have a more aggressive course.…”

“…They usually arise in the cauda equina/filum terminale region comprising 3.5 % of all cauda tumors (17,18,20) and in the lumbar region as well (14). Only fifteen cases in the thoracic region (18,22) and two in the cervical region have been reported to date (18).…”

“…Nuclear pleomorphism is generally mild and scattered mitotic figures can be seen. Besides their classical alveolar pattern (Zellballen), they sometimes exhibit a variety of histological features with spindle cells (14), ganglionic cells (21) or with melanotic, carcinoid tumor-like growth patterns (20) which may cause a diagnostic problem.…”

“…PGs of the central nervous system (CNS) are uncommon and usually arise from the cauda equina/filum terminale region (18) or less commonly from the spinal nerve roots (14,20). These are WHO grade I neoplasms and the prognosis is excellent when totally resected (18).…”

Neuronal and Mixed Neuronal-Glial Tumors of the Central Nervous System

“…Some paragangliomas of the cauda equina region show architectural features similar to carcinoid tumors, including angiomatous, adenomatous, and pseudorosette patterns. Tumors composed predominantly of spindle and melanincontaining cells (melanotic paragangliomas) have also been described at this site, as has oncocytic paraganglioma (220,221,222). hemorrhagic necrosis may also occur, and scattered mitotic figures can be seen.…”