Remission and Recurrence of Disease Following Apoplexy of Functional Pituitary Adenomas

Introduction: Functional pituitary adenomas (PAs) often underlie the development of Cushing’s disease, acromegaly, and hyperprolactinemia. A rare occurrence in these adenomas is apoplexy which can result in spontaneous hormonal remission and tumor shrinkage. Although limited studies report the remission of functional adenomas following apoplexy, rates of recurrence and potential risk factors are not well defined. We review outcomes published within the past 10 years to better understand the rates of remission and recurrence of functional hormone-secreting pituitary tumors.

Methods: We conducted a literature review for articles published within January 2012 to August 2022 on Google Scholar and on PubMed. Search terms were: ACTH-secreting adenoma, Cushing’s disease, GH-secreting adenoma, acromegaly, prolactinoma, pituitary apoplexy. Inclusion criteria were patients >18 years old, those with a diagnosis of pituitary apoplexy of a functional adenoma supported by MRI imaging, hormone panel, and clinical symptoms with postoperative follow up. Recurrence was defined as tumor regrowth, abnormal hormone levels and/or recrudescence of prior symptoms.

Results: Seventy-one patients were identified with functional PAs and apoplexy who experienced initial remission of their disease. Of 30 patients with Cushing’s disease and acromegaly, 10 had recurrent disease. All were female and the average remission period was 51.9 months. None of the 10 patients reviewed with acromegaly had recurrent disease. Of 31 patients with hyperprolactinemia, only one had recurrence and repeat apoplexy.

Conclusion : Pituitary apoplexy in functional adenomas can result in spontaneous remission due to tumor cell death. However, the rate of recurrence and clinical characteristics or risk factors associated with recurrence are not well defined. In our review, we found that most functional adenomas undergo long-term, if not permanent remission. Recurrence was higher in Cushing’s disease compared to other functional adenomas; these patients should undergo continued long-term surveillance and possibly surgical resection.