Acromegaly

Acromegaly – Treatment Options

Introduction
Acromegaly is a chronic endocrine disorder caused by excessive secretion of growth hormone (GH), usually from a pituitary adenoma, leading to elevated insulin-like growth factor 1 (IGF-1). Clinical manifestations include acral enlargement, facial feature coarsening, soft tissue overgrowth, metabolic disturbances, and increased risk of cardiovascular disease. Treatment aims to normalize GH and IGF-1 levels, control tumor growth, alleviate symptoms, and reduce morbidity and mortality.

1. Surgical Therapy (First-Line Treatment)

• Transsphenoidal surgery (TSS):

  • Standard initial therapy for GH-secreting pituitary adenomas.

  • Goal: Complete tumor removal, normalization of GH/IGF-1, and decompression of optic structures.

  • Outcomes: Highest cure rates in microadenomas; lower in invasive macroadenomas.

2. Medical Therapy

• Somatostatin receptor ligands (SRLs):

  • Octreotide LAR: 20–40 mg IM every 4 weeks.

  • Lanreotide autogel: 60–120 mg SC every 4 weeks.

  • Pasireotide LAR: 40–60 mg IM every 4 weeks; effective in resistant cases, but may induce hyperglycemia.

  • Mechanism: Inhibit GH secretion and shrink tumor size in many patients.

• GH receptor antagonist:

  • Pegvisomant: 10–40 mg SC daily.

  • Blocks GH action at receptor level, normalizes IGF-1 in most patients.

  • Does not reduce tumor size; requires liver function monitoring.

• Dopamine agonists:

  • Cabergoline: 0.5–3.5 mg per week orally.

  • Less effective than SRLs or pegvisomant; useful in mild disease or as adjunct.

3. Radiation Therapy

• Stereotactic radiosurgery (e.g., Gamma Knife, CyberKnife):

  • For residual or unresectable tumors not controlled with medical therapy.

  • May take years to achieve full effect.

• Conventional fractionated radiotherapy:

  • Reserved for large or invasive tumors not suitable for surgery or radiosurgery.

  • Carries higher long-term risk of hypopituitarism.

4. Supportive and Symptomatic Management

• Metabolic complications:

  • Diabetes mellitus: Standard antihyperglycemic therapy, but glucose intolerance may worsen with pasireotide.

  • Hypertension: Antihypertensive therapy tailored to cardiovascular risk.

• Sleep apnea: Evaluation with polysomnography; treatment with CPAP as needed.

• Arthropathy and joint pain: Physical therapy, analgesics, or orthopedic referral.

5. Monitoring and Follow-Up

• Biochemical: Regular IGF-1 and GH measurement to assess treatment efficacy.

• Imaging: Pituitary MRI for tumor monitoring.

• Endocrine function: Periodic testing for hypopituitarism after surgery or radiation.

• Cardiovascular assessment: Echocardiography and vascular risk evaluation.

6. Multidisciplinary Care

• Endocrinologists for long-term medical management.

• Neurosurgeons for surgical intervention.

• Radiation oncologists for radiotherapy when indicated.

• Cardiologists, pulmonologists, and orthopedists for management of comorbidities.