Three cases of pituitary adenoma with extension into the nasopharynx and nasal cavity are reported. The occurrence of this rare tumor underscores the need to consider a pituitary tumor whenever a patient presents with rhinologic complaints and destruction of the sellar floor. Epistaxis, although exceptional, may be the first manifestation of a pituitary tumor. Immunohistochemical analysis combined with staining for the pituitary hormones proved to be essential for reaching a definite diagnosis. Magnetic resonance imaging seems to be the modality of choice for differentiation between tumorous and nontumorous sinus obstruction.