Predictors of prolonged hypogonadism in men with prolactinomas despite biochemical remission: the role of baseline luteinizing hormone.

purposeRecovery of gonadal function in men with prolactinomas following dopamine agonist therapy is variable, and predictors of hypogonadism remain unclear. We aimed to identify predictors of prolonged hypogonadotropic hypogonadism (HH) in men achieving normoprolactinemia during cabergoline therapy.

methodsIn this retrospective cohort study, 71 male patients with prolactinomas were screened; 51 were included in the baseline analysis, and 39 patients achieving biochemical remission with adequate follow-up were included in the longitudinal outcome analysis. Prolonged hypogonadism was defined as persistence of low testosterone levels for > 12 months after prolactin normalization. Predictors were assessed using group comparisons, univariate logistic regression, and ROC curve analysis.

resultsProlonged HH was observed in 25.6% of patients despite prolactin normalization. Baseline LH demonstrated high discriminative performance (AUC: 0.886), with a cut-off ≤ 2.47 IU/L yielding high specificity (93.1%). Baseline total testosterone (AUC: 0.829, ≤ 1.95 ng/mL [6.8 nmol/L]), prolactin (AUC: 0.802, ≥ 141.9 ng/mL), and tumor diameter (AUC: 0.780, ≥ 7.6 mm) were also associated with prolonged HH. Longitudinal trajectories demonstrated increases in LH and testosterone during the first 12 months, followed by a plateau phase. However, testosterone recovery remained incomplete in the prolonged HH group, although delayed normalization was observed during follow-up.

conclusionBaseline LH was strongly associated with prolonged hypogonadism in prolactinomas and may serve as a marker for early risk stratification. Most hormonal recovery occurred within the first 12 months after prolactin normalization, supporting the clinical relevance of this time point. Baseline hormonal and structural parameters may help guide follow-up and testosterone replacement decisions.