Pituitary carcinoma is a rare disease with a challenge in both diagnosis and treatment. A 50-year-old female patient who underwent transsphenoidal resection of a pituitary tumor experienced progressive headache. For the evaluation, Ga DOTATATE PET/CT was used and compared with F-FDG PET/CT and enhanced MRI. Multiple lesions were detected by Ga DOTATATE PET/CT at the cerebral cortex, cerebellum, and cerebellopontine angle with a higher contrast than F-FDG PET/CT and enhanced MRI. With a biopsy, the patient was diagnosed as metastatic pituitary carcinoma. Moreover, it thus presents potential therapeutic implications on molecular-targeted therapy using somatostatin analogs and peptide receptor radionuclide therapy targeting the somatostatin receptors.