Chronic expanding pituitary hematoma with calcification resulting from pituitary adenoma: illustrative case

BACKGROUND: Pituitary apoplexy (PA) is characterized by sudden headache, vomiting, visual dysfunction, anterior lobe dysfunction, and endocrine disorder due to bleeding or infarction from a pituitary adenoma. PA occurs in approximately 0.6–10% of pituitary adenomas, more commonly in men aged 50–60 years, and more frequently in nonfunctioning and prolactin-producing pituitary adenomas. Further, asymptomatic hemorrhagic infarction is found in approximately 25% of PA. OBSERVATIONS: A pituitary tumor with asymptomatic hemorrhage was detected on head magnetic resonance imaging (MRI). Thereafter, the patient underwent head MRI every 6 months. After 2 years, the tumor was enlarged and visual dysfunction was noticed. The patient underwent endoscopic transnasal pituitary tumor resection and was diagnosed with a chronic expanding pituitary hematoma with calcification. The histopathological findings were very similar to those of chronic encapsulated expanding hematoma (CEEH). LESSONS: CEEH associated with pituitary adenomas gradually increases in size, causing visual dysfunction and pituitary dysfunction. In case of calcification, total removal is difficult due to adhesions. In this case, calcification developed within 2 years. A pituitary CEEH, even when showing calcification, should be operated on, as visual function can be fully recovered.