RESUMEN
We report the case of a young woman who presented with cerebrospinal fluid (CSF) rhinorrhea due to an undiagnosed and untreated pituitary adenoma. The tumor had extended well beyond sella turcica and caused bony erosion. The patient initially refused surgery and was treated with bromocriptine and a radiation therapy. CSF leakage did not improved and she was submitted to surgery by the transsphenoidal approach with removal of a tumor mass located in sphenoid sinus and sellar region. Origin of the leak was localized and repaired with fascia lata and a lumbar subarachnoid drain was left in place for 5 days. After 4 years she has normal serum PRL levels and no rhinorrhea. The management, complications and mechanisms involved in this rare condition are discussed