PARAGANGLIOMA OF THE CAUDA-EQUINA

We report on a case of paraganglioma of the cauda equina in a 48-year- old man. These slow-growing, mostly benign and encapsulated intradural -extramedullar rumours are clinically characterized by lumbago, paraes thesia and motor deficits as well as occasionally by incontinence. Par agangliomas of the cauda equina show monomorphous (main) cells arrange d in a typical cell cluster pattern, demonstrating a lobular architect ure a nd a fine net of connective tissue formed by so-called sustentac ular cells; some tumours show focal ganglionic differentiation. Becaus e of their morphological similarity to the more common ependymomas, pa ragangliomas of the cauda equina are sometimes misdiagnosed so that th eir incidence is likely to be higher than previously estimated. Immuno histochemistry findings are positive for neuron-specific enolase, chro mogranin and other neuronal markers as well as neuropeptides (main cel ls) and S-100 protein (sustentacular cells) while widely lacking react ivity for GFAP. Paragangliomas of the cauda equina represent a rare en tity, of which only 80 cases have been described in the literature. Be cause they only occur sporadically, they are often not included in the differential diagnosis of mass lesions of the region of the cauda equ ina.