TOPLINE:

Among patients with multiple endocrine neoplasia type 1 (MEN1), the likelihood of developing pituitary adenomas was higher at younger ages and declined with time. Other key risk factors identified were a history of primary hyperparathyroidism, non-missense MEN1 pathogenic variants, and being a woman.

METHODOLOGY:

• Researchers in Spain conducted a retrospective cohort study to identify risk factors for the development of pituitary adenoma in 240 patients with MEN1 from 57 unrelated families.
• MEN1 was diagnosed when patients presented with at least two of the three major lesions — primary hyperparathyroidism, enteropancreatic neuroendocrine tumour, or pituitary adenoma — regardless of germline pathogenic variant status.
• Patients' demographics along with clinical, radiologic, and histologic data of MEN1 disease and pituitary adenomas were collected; diagnosed pituitary adenomas were classified on the basis of initial imaging according to Hardy's classification and also classified on the basis of laboratory test results as functioning or non-functioning.
• Outcomes assessed were the development of pituitary adenoma and its associated risk factors.
• The median follow-up duration was 6 years.

TAKEAWAY:

• In the whole cohort, pituitary adenomas were diagnosed in 112 patients (46.6%; mean age at diagnosis, 36.1 years; 54.5% women); these tumours became 50% penetrant at a mean age of 50 years, and prolactinomas and microadenomas were the predominant tumour types identified.
• Because 41 patients had already been diagnosed with a pituitary adenoma before their MEN1 diagnosis, the remaining 199 were prospectively followed up and 71 were eventually found to have a pituitary adenoma.
• Independent risk factors for the development of pituitary adenoma in the full cohort were age (per additional year; adjusted hazard ratio [aHR], 0.916; P < .001), prior primary hyperparathyroidism (aHR, 3.090; P < .001), non-missense MEN1 pathogenic variants (aHR, 1.976; P = .018), and being a woman (aHR, 1.706; P = .022); outcomes were comparable for the screened cohort.
• A separate analysis revealed that getting diagnosed with MEN1 before the age of 26 years was linked to an increased risk for the development of pituitary adenomas.

IN PRACTICE:

"[The study] findings could assist clinicians in better informing patients about their individual risk and in guiding personalized PA [pituitary adenoma] screening strategies," the authors wrote.

SOURCE:

This study was led by Nuria Valdés, MD, PhD, Hospital Universitario Cruces, Bilbao, Spain. It was published online on September 08, 2025, in The Journal of Clinical Endocrinology and Metabolism.

LIMITATIONS:

This study was retrospective in nature, and findings were derived from a single national registry. Data obtained from referring physicians rather than a centralised core centre may have led to variability and inconsistencies. Advances in MRI technology during the study period may have influenced microadenoma detection rates.

DISCLOSURES:

This study did not receive any funding. The authors reported having no relevant conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.