Extranodal Rosai-Dorfman disease with multiple spinal lesions: a rare presentation.

BACKGROUND: Rosai-Dorfman disease is an idiopathic histiocytic proliferative disorder characterized by sinus histiocytosis and massive lymphadenopathy. Extranodal involvement is rare and central nervous system (CNS) involvement is unusual. We present a case of a multiple-level spinal involvement by Rosai-Dorfman disease without cervical lymphadenopathy, which is distinctly rare. Very few cases have been reported in literature. Its resemblance with meningiomas both clinically and radiologically makes its diagnosis all the more difficult. CASE DESCRIPTION: A 23-year-old woman presented with quadriparesis and incontinence of urine and stool with a history of being operated on twice for dorsal spine tumor. On examination she had hypoesthesia below the C6 vertebra with anesthesia below D3, and absent joint position and vibration sensations. The patient had spasticity in lower limbs with normal tone in upper limbs. Deep tendon reflexes were hyporeflexic in upper limbs and hyperreflexic in lower limbs with bilateral ankle clonus with bilateral Babinski sign. Magnetic resonance imaging of the cervicodorsal spine was suggestive of multiple intradural extramedullary space-occupying lesion with probability of meningiomas. Surgical resection of 3 tumors was done and sent for histopathology, which was suggestive of sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease). The patient had good postoperative recovery and was followed up for 5 months with no new complaints.
CONCLUSION: Rosai-Dorfman disease is a rare entity having clinical and radiological similarity to meningioma. It is similar to lymph node histiocytosis and rarely involves the CNS. It is a benign lymphohistiocytic proliferative condition of unknown etiology. Histopathology showing emperipolesis (lymphophagocytosis) and immunohistochemistry showing S-100 positivity is diagnostic. Surgical resection is the treatment of choice.