Malignant prolactinomas, as with other pituitary carcinomas, are rare tumors. The authors describe a 14-year-old boy who presented with visual loss caused by a pituitary prolactinoma. He underwent transsphenoidal surgery, radiotherapy, and dopamine agonist therapy, but 6 years after the initial diagnosis his pituitary tumor regrew and bone and pulmonary metastases developed. The authors review the literature and discuss the clinical presentation of malignant prolactinomas, their rarity, histological characteristics, distribution of the metastases, different treatment approaches, and their poor prognosis.