A case of late diagnosis of somatotroph pituitary adenoma

Acromegaly is a rare neuroendocrine disorder with an incidence of 3–5 new cases per million population annually. Delayed diagnosis of 5–10 years contributes to the development of pituitary macroadenomas and severe systemic complications. This case report evaluates the dynamics of hormonal, metabolic, and radiological parameters following surgical treatment and radiotherapy in a patient with pituitary macroadenoma and severe acromegaly. A female patient, born in 1981, presented with headache, visual impairment, anosmia, galactorrhea, somnolence, weight gain, amenorrhea, acral enlargement, facial coarsening, weakness, hyperhidrosis, and arthralgia. Symptoms had persisted for 6 years. Initial laboratory findings on November 4, 2025, demonstrated GH 50.0 ng/mL, IGF-1 929 ng/mL, prolactin 25.1 ng/mL, and glucose 6.05 mmol/L. MRI revealed a pituitary macroadenoma measuring 28.4 × 25.4 × 23.6 mm with supra-, infra-, and parasellar extension. Endoscopic endonasal transsphenoidal adenomectomy was performed on December 11, 2025. On postoperative day 1, GH was 45.7 ng/mL, IGF-1 was 646.1 ng/mL, and prolactin was 0.29 ng/mL. Radiotherapy was administered for 28 days beginning January 22, 2026. At 3-month follow-up on March 14, 2026, IGF-1 decreased to 112 ng/mL and GH to 6.90 ng/mL. Follow-up MRI on April 15, 2026, demonstrated residual adenoma measuring 21 × 9 × 18 mm. Despite significant biochemical improvement, persistently elevated GH levels and residual tumor tissue indicated partial biochemical remission. Acromegaly was diagnosed 6 years after symptom onset and was associated with marked hormonal hypersecretion. Combined treatment achieved partial biochemical remission; however, residual adenoma and elevated GH levels necessitate continued follow-up and evaluation of delayed radiotherapeutic effects.