Seeding of a Pituitary Adenoma or Atypical Pituitary Carcinoma?

Pituitary carcinomas are defined as pituitary tumors with craniospinal and/or systemic metastasis. These are rare and highly aggressive lesions. We present an unusual case of a 52-year-old male who had a pituitary adenoma removed via craniotomy. The tumor recurred three years post-op near the surgical tract, and slowly enlarged before removal two years later. Technically, this lesion was defined as a pituitary carcinoma, even though the histology and clinical course were atypical. There is no standardized grading system for pituitary tumors and ideal criteria should correlate clinically. Treatment for pituitary carcinoma is multimodal and largely empiric. We believe this case illustrates that current definitions of pituitary carcinoma are incomplete.