Longitudinal changes in nonfunctioning pituitary neuroendocrine tumors in children receiving growth hormone therapy:...

Background: Growth hormone deficiency (GHD) may result from structural abnormalities or space-occupying lesions of the pituitary gland; therefore, pituitary magnetic resonance imaging (MRI) is routinely performed as part of the etiological assessment. The reported prevalence of incidentally detected pituitary neuroendocrine tumors (PitNETs) in pediatric patients with GHD ranges from 0.5% to 20.3% across studies. PitNETs are rare in childhood and account for approximately 2.7% of supratentorial pediatric tumors and 3.6-6% of surgically treated PitNETs. Insulin-like growth factor-1 (IGF-I), a mitogenic agent elevated during recombinant human growth hormone (rhGH) therapy, has raised theoretical concerns regarding tumor growth stimulation. Objective: To evaluate longitudinal changes in tumor size of nonfunctional PiNETs, in patients with pre-existing PitNETs receiving rhGH therapy compared with untreated controls. Methods: This single-center retrospective cohort study included 15 GHD patients with PitNETs detected before rhGH initiation and 30 control patients with nonfunctional incidental PitNETs who did not receive rhGH therapy. Radiological follow-up was performed at baseline and at 6, 12, 18, 24, and 36 months. Results: No significant longitudinal changes in PitNETs width or length were observed in either group. One rhGH-treated patient underwent PitNET excision. Indications for pituitary imaging in the control group were predominantly central precocious puberty, headache, central hypothyroidism, and short stature. Conclusion: RhGH therapy was not associated with significant progression of nonfunctional PitNETs during a 36-month follow-up, supporting its safety when accompanied by regular radiological surveillance.