Clinical Features and Key Prognostic Indicators of Growth Hormone-Secreting Pituitary Adenomas: A Retrospective Study of 344 Cases

Background: In growth hormone-secreting pituitary adenomas (GHPA), postoperative hormonal non-remission and tumor recurrence determine clinical prognosis. Notably, some patients exhibit persistent hormonal abnormalities despite intraoperative gross total resection (GTR). This study systematically analyzes the prognostic risk factors in GHPA. Methods: This study collected clinical information from 344 GHPA patients. Univariate and multivariate regression analyses were performed to screen independent risk factors for hormonal non-remission, tumor recurrence, and hormonal non-remission after GTR. Nomograms were established for predicting hormonal non-remission and 3-/5-year recurrence probabilities. Subgroup comparisons were performed to further analyze significant risk factors. Results: Multivariate Logistic regression identified recurrent cases (p = 0.009), preoperative GH > 40 ng/mL (p = 0.043), not GTR (p < 0.001), and Knosp grade IV (p = 0.004) as independent risk factors of postoperative hormonal non-remission. For patients who underwent GTR, the recurrent status (p = 0.016) and Knosp grade III/IV (p = 0.049/0.009) remained significant risk factors for hormonal non-remission. Multivariate Cox regression showed preoperative GH > 40 ng/mL (p = 0.002), hormonal non-remission (p = 0.037), Knosp grade IV (p = 0.025), and vision defect (p = 0.010) as independent risk factors for tumor recurrence. The nomograms had good discrimination and calibration, with test set AUCs of 0.828 for hormonal non-remission, 0.82 for 3-year recurrence, and 0.859 for 5-year recurrence. Subgroup analysis revealed that recurrent cases, compared to initial cases, had younger patient ages, higher Knosp grades, harder tumor textures, and generally higher Ki-67 indices (all p < 0.05). Further analysis demonstrated that, relative to Knosp grade III tumors, grade IV lesions were larger, firmer, and associated with significantly lower rates of both GTR and hormonal remission, alongside a higher recurrence risk (all p < 0.05). Conclusions: Patients with high preoperative GH levels, higher Knosp grades, and recurrence often have a poorer prognosis after treatment. These results support stratified postoperative management and individualized monitoring of GHPA patients.