What are the signs, symptoms, diagnosis, treatment, and follow-up care for pituitary tumors?

Diagnosis and Management of Pituitary Tumors

Pituitary tumors require multidisciplinary assessment and care, including systematic pituitary hormone assessment, dedicated neuroimaging, visual evaluation, and management by an expert pituitary team to optimize outcomes and minimize long-term complications. 1

Signs and Symptoms

Mass Effect Symptoms

• Visual field defects (18-78% of macroadenomas)
• Headache (17-75% of macroadenomas)
• Cranial nerve palsies (especially with larger tumors)
• Symptoms of increased intracranial pressure

Hormonal Symptoms

• Prolactinoma (53% of pituitary adenomas):

  • Women: Amenorrhea, galactorrhea, infertility, decreased libido
  • Men: Decreased libido, erectile dysfunction, infertility

• Growth Hormone-Secreting (12% of adenomas):

  • Adults: Acromegaly (enlargement of hands, feet, lips, tongue, nose)
  • Children: Gigantism, rapid growth velocity

• ACTH-Secreting (4% of adenomas):

  • Cushing's disease: Central obesity, hypertension, diabetes, purple striae, muscle weakness

• TSH-Secreting (1% of adenomas):

  • Hyperthyroidism: Weight loss, anxiety, palpitations, heat intolerance

• Non-functioning adenomas (30% of adenomas):

  • Usually present with mass effect symptoms
  • Hypopituitarism (34-89% of macroadenomas)

Diagnosis

Imaging

• MRI with contrast is the method of choice 2
  • T1 and T2-weighted images with fat suppression sequences 1
  • Determines tumor size, extension, and relationship with adjacent structures

Endocrine Evaluation

• Complete pituitary hormone assessment:
  • Prolactin
  • Growth hormone and IGF-1
  • ACTH and cortisol (late-night salivary cortisol for Cushing's)
  • TSH and free T4
  • LH, FSH, testosterone (men) or estradiol (women)
  • Assessment for diabetes insipidus

Visual Assessment

• Formal visual field testing for all macroadenomas approaching the optic chiasm 1, 3

Histopathology

• Required for correct tumor classification
• Includes assessment of pituitary hormones and proliferative markers 4

Genetic Testing

• Consider in young patients or those with family history of pituitary tumors
• Especially important in children and adolescents 1

Treatment

Medical Therapy

• Prolactinomas:
  • First-line: Dopamine agonists (bromocriptine or cabergoline) 2, 3
  • Bromocriptine: Start at 1.25-2.5 mg/day, gradually increase to effective dose 5
  • Caution with bromocriptine: May cause hypotension, somnolence 5

Surgical Therapy

• First-line treatment for most non-prolactin secreting adenomas 2, 3
• Transsphenoidal approach preferred over craniotomy 6
• Endoscopic techniques increasingly used over microscopic approaches 1
• Indications:
  • Non-functioning adenomas causing mass effects
  • GH-secreting, ACTH-secreting, and TSH-secreting adenomas
  • Prolactinomas resistant to medical therapy

Radiation Therapy

• Consider when tumor is symptomatic, growing, resistant to medical therapy, and surgically inaccessible 1
• Options:
  • External beam fractionated radiotherapy (45-50.4 Gy in 1.8 Gy daily fractions)
  • Stereotactic radiosurgery for selected cases
• Caution in young patients due to increased risk of secondary tumors:
  • 3.34× higher risk of malignant brain tumors
  • 4.06× higher risk of meningiomas 1

Treatment Algorithm by Tumor Type

1. Prolactinomas:

   • First-line: Medical therapy with dopamine agonists
   • Second-line: Surgery if resistant to medical therapy

2. GH-secreting, ACTH-secreting, TSH-secreting:

   • First-line: Transsphenoidal surgery
   • Second-line: Medical therapy and/or radiation therapy

3. Non-functioning adenomas:

   • Symptomatic: Transsphenoidal surgery
   • Asymptomatic microadenomas: Observation with serial imaging

4. Aggressive tumors/carcinomas:

   • Temozolomide after failure of standard therapies 4

Follow-up Care

Immediate Post-operative Care

• Monitor for diabetes insipidus (26% incidence) and SIADH (14% incidence) 2
• Assess for cerebrospinal fluid leaks
• Evaluate pituitary function

Radiologic Follow-up

• First MRI at 3 months post-surgery to evaluate extent of resection 1, 2
• Subsequent MRI at 6 months, then at 1,2,3, and 5 years 2
• For incidental macroadenomas: MRI at 6 months, then annually for 3 years 2

Endocrine Follow-up

• Regular assessment of pituitary function
• Hormone replacement as needed:
  • Levothyroxine for central hypothyroidism
  • Hydrocortisone for adrenal insufficiency
  • Sex hormone replacement
  • Growth hormone replacement if deficient
  • Desmopressin for diabetes insipidus

Visual Follow-up

• Visual field testing within 3 months after treatment 2
• Regular ophthalmologic follow-up for patients with pre-treatment visual deficits

Special Considerations

Pituitary Apoplexy

• Medical emergency requiring immediate treatment
• Symptoms: Sudden headache, visual disturbances, altered consciousness
• Management: High-dose steroids, urgent surgical decompression if visual compromise 1

Hormone Replacement in Hypopituitarism

• Glucocorticoids: Hydrocortisone 15-20 mg/day divided
• Thyroid: Levothyroxine 1.6 μg/kg/day
• Sex hormones: Testosterone for men; estrogen with/without progestogen for women
• Growth hormone: 0.025 mg/kg per day for confirmed deficiency 2

Emergency Management

• For adrenal crisis: Immediate IV/IM hydrocortisone 100 mg, followed by 100 mg every 6-8 hours 2
• All patients with hypopituitarism should wear medical alert identification 2

Long-term Monitoring

• Lifelong follow-up is essential for all patients with pituitary tumors 7
• Annual assessment of:
  • Pituitary function
  • Adequacy of hormone replacement
  • Tumor recurrence or growth
  • Visual function if previously affected
  • Cardiovascular risk factors
  • Bone health
  • Quality of life 2

By implementing comprehensive diagnostic evaluation, appropriate treatment selection, and vigilant follow-up care, patients with pituitary tumors can achieve good long-term outcomes with minimized morbidity and mortality.