TOPLINE:

Although hypogonadism was the most prevalent pituitary hormone deficiency, non-gonadal hypopituitarism affected 14.5% of patients with prolactinomas. Tumour size was the strongest predictor of hormonal deficits at both diagnosis and potential recovery, with 17 mm identified as the optimal threshold.

METHODOLOGY:

• Researchers conducted a retrospective multicentre study at two tertiary centres in Italy to evaluate the prevalence of pituitary hormone deficiencies in prolactinomas, identify clinical and radiologic predictors of non-gonadal hypopituitarism at diagnosis, and evaluate the potential for the recovery of pituitary function over long-term follow-up.
• They analysed 145 patients diagnosed with prolactinomas between 2000 and 2024 (mean age, 36.9 years; 67.6% women); diagnosis was based on hyperprolactinaemia with signs and/or symptoms attributable to it, together with the evidence of a pituitary adenoma on MRI.
• At diagnosis, each patient was assessed for clinical signs and symptoms of hypopituitarism and underwent evaluation of gonadotroph, thyrotroph, corticotroph, and somatotroph hormonal axes, with hypopituitarism defined as the deficient secretion of one or more pituitary hormones according to the criteria of routine clinical practice.
• A total of 140 patients received cabergoline as first-line therapy, starting at 0.5 mg once or twice weekly, with dose adjustments on the basis of serum prolactin levels.
• The median follow-up duration was 70.0 months for this study.

TAKEAWAY:

• At diagnosis, 37.2% of patients had at least one pituitary hormone deficiency, with hypogonadism being the most common (34.5%), and non-gonadal hypopituitarism was found in 14.5% of patients, which included secondary adrenal insufficiency (8.3%), central hypothyroidism (7.6%), and growth hormone deficiency (6.9%).
• Macroadenomas showed significantly higher rates of non-gonadal hypopituitarism than microadenomas (25.8% vs 2.7%; P < .001).
• Tumour size independently predicted non-gonadal hypopituitarism at diagnosis (odds ratio [OR], 1.1; P = .007); a tumour size of 17 mm was identified as the optimal cutoff, with an area under the curve of 0.836 (sensitivity, 84%; specificity, 77%).
• The recovery of at least one pituitary axis occurred in 66.7% of patients during follow-up, with higher rates of recovery seen in those with microadenomas than in those with macroadenomas (100% vs 63.0%; P = .038); tumour size was an independent predictor of recovery (OR, 0.56; P = .029).

IN PRACTICE:

"Integrating tumor size into the initial risk assessment may help identify patients who require closer endocrine monitoring and early hormone replacement, while also recognizing those with smaller, non-invasive tumors who are more likely to recover pituitary function after DA [dopamine agonist] therapy," the authors wrote.

SOURCE:

This study was led by Antonio Prinzi, Endocrinology Unit, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy. It was published online on November 10, 2025, in Frontiers in Endocrinology.

LIMITATIONS:

The retrospective design introduced potential biases related to missing or incomplete information. The assessment of growth hormone deficiency relied solely on insulin-like growth factor type 1 concentrations rather than dynamic testing, potentially underestimating its true prevalence. Data regarding the Knosp grade for tumour invasiveness and cystic morphology were not consistently available across centres.

DISCLOSURES:

This study did not receive any funding. The authors declared having no 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.