SPHENOID SINUS BROWN TUMOR OF SECONDARY HYPERPARATHYROIDISM - CASE-REPORT

OBJECTIVE AND IMPORTANCE: Brown tumor is a misnomer for a reparative c ellular process caused by primary or, less commonly, secondary or tert iary hyperparathyroidism. Atypical involvement of the base of the cran ium in the area of the sphenoid sinus and the orbit is exceedingly rar e and may produce a neurological deficit as a primary clinical present ation. Those neurosurgeons dealing with cranial base and pituitary les ions should be aware of this disease entity, and it should be listed i n the differential diagnosis. CLINICAL PRESENTATION: A 21-year-old wom an with end-stage renal failure on chronic dialysis was referred to th e Department of Neurosciences at King Faisal Specialist Hospital and R esearch Centre with a 4-month history of progressive impairment of vis ion, associated with headache and nausea. Computed tomography and magn etic resonance imaging demonstrated an expansive mass lesion in the sp henoid sinus with erosion of the sellar floor and posterior medial wal l of the orbit causing compression of the optic nerves. The biochemica l laboratory studies showed elevation of parathyroid hormone and confi rmed the diagnosis of hyperparathyroidism. INTERVENTION: The transnasa l-transsphenoidal approach was used for extensive microsurgical remova l of the lesion. The postoperative course was uneventful, and the impr ovement in vision was dramatic. CONCLUSION: Brown tumor, although rare , should be listed in the differential diagnosis of expansive mass les ions in the area of the sphenoid sinus and cranial base. The managemen t is multidisciplinary, and therapeutic options should target the unde rlying cause.