Congress of Neurological Surgeons Systematic Review and Evidence-Based Guideline on Primary Management of Patients With Nonfunctioning Pituitary Adenomas.

BACKGROUND: Nonfunctioning pituitary adenomas (NFPAs) are among the most common pituitary lesions and may present clinically with vision loss and hypopituitarism.
OBJECTIVE: To characterize the existing literature as it pertains to the initial management of NFPAs.
METHODS: A systematic literature review was conducted to identify and screen articles assessing primary treatment options (surgical, medical, radiation based, or observation) for NFPAs. Outcomes assessed included vision-, endocrine-, and headache-related symptoms, as well as tumor response to therapy. Twenty-five studies met inclusion criteria for analysis.
RESULTS: A considerable amount of class II evidence (14 studies) was identified supporting primary surgical intervention in patients with symptomatic NFPA macroadenomas, resulting in immediate tumor volume reduction in nearly all patients and a residual tumor rate of 10% to 36%. One prospective, observational cohort study and multiple retrospective studies showed improved visual function in 75% to 91% of surgically treated patients and improved hypopituitarism in 35% to 50% of patients. Limited class II evidence showed inconsistent benefits for observation alone (1 study), primary radiation-based treatment (3 studies), or primary medical treatment (8 studies) for improving vision, headaches, hypopituitarism, or tumor volume. One retrospective study implementing observation alone showed tumor progression in 50% of patients and a requirement for surgery in 21% of patients. Eight studies assessing primary medical therapy for NFPAs showed inconsistent tumor response rates using somatostatin analogs (12%-40% response rate), dopamine agonist therapy (0%-61% response rate), or combination therapy (60% response rate). Three studies reporting primary radiosurgery for NFPAs showed decreased tumor size in 38% to 60% of patients.
CONCLUSION: Multiple retrospective and some prospective studies have demonstrated consistent effectiveness of primary surgical resection of symptomatic NFPAs with acceptable morbidity rates. Limited and inconsistent reports are available for alternative treatment strategies, including radiation, medical treatment, and observation alone; these modalities may, however, play a valid role in patients who are not surgical candidates. Based on the available evidence, the authors recommend surgical resection as the preferred primary intervention for symptomatic NFPAs. The full guidelines document for this chapter can be located at https://www.cns.org/guidelines/guidelines-management-patients-non-functioning-pituitary-adenomas/Chapter_5. ABBREVIATION: NFPA, nonfunctioning pituitary adenoma.