Background: Double pituitary adenomas are rare presentations of two distinct adenohypophyseal lesions seen in <1% of surgical cases. Increased rates of recurrence or persistence are reported in the resection of Cushing microadenomas and are attributed to the small tumor size and localization difficulties. The authors report a case of surgical treatment failure of Cushing disease because of the presence of a secondary pituitary adenoma.
Observations: A 32-year-old woman with a history of prolactin excess and pituitary lesion presented with oligomenorrhea, weight gain, facial fullness, and hirsutism. Urinary and nighttime salivary cortisol elevation were elevated. Magnetic resonance imaging confirmed a 4-mm3 pituitary lesion. Inferior petrosal sinus sampling was diagnostic for Cushing disease. Primary endoscopic endonasal transsphenoidal resection was performed to remove what was determined to be a lactotroph-secreting tumor on immunohistochemistry with persistent hypercortisolism. Repeat resection yielded a corticotroph-secreting tumor and postoperative hypoadrenalism followed by long-term normalization of the hypothalamic-pituitary-adrenal axis.
Lessons: This case demonstrates the importance of multidisciplinary management and postoperative hormonal follow-up in patients with Cushing disease. Improved strategies for localization of the active tumor in double pituitary adenomas are essential for primary surgical success and resolution of endocrinopathies.
Keywords: Cushing disease; PitNET; pituitary adenoma; pituitary neuroendocrine tumor; prolactinoma; transsphenoidal.