What are the management and treatment options for carcinoid tumors?

Management and Treatment of Carcinoid Tumors

Surgical resection is the primary curative treatment for localized carcinoid tumors, while somatostatin analogs are the first-line therapy for controlling symptoms and tumor growth in metastatic disease. 1

Diagnosis and Evaluation

• Imaging studies:

  • Multiphase CT or MRI (first-line for suspected carcinoid tumors)
  • Somatostatin receptor scintigraphy using [111In-DTPA]-octreotide
  • 68Ga-DOTA-peptide PET/CT (if available)
  • Site-specific evaluations:
    • Colonoscopy and small bowel imaging for jejunal/ileal/colon carcinoids
    • Endoscopic ultrasound (EUS) for duodenal and gastric carcinoids
    • Proctoscopic examination for rectal carcinoids
    • Bronchoscopy for bronchopulmonary carcinoids 1, 2

• Biochemical markers:

  • Chromogranin A (general marker for both functioning and non-functioning tumors)
  • 24-hour urine 5-HIAA collection (for suspected carcinoid syndrome)
  • Neuron-specific enolase (alternative marker when CgA is not elevated) 2

Treatment Approach Based on Disease Stage

1. Localized Disease

• Surgical resection is the primary treatment approach with curative intent 1

• Specific approaches by tumor location:

  • Gastric carcinoids:

    • Type 1 (associated with atrophic gastritis) and Type 2 (associated with Zollinger-Ellison syndrome):
      • Tumors ≤2 cm: Endoscopic resection, observation, or octreotide (for Zollinger-Ellison syndrome)
      • Tumors >2 cm: Endoscopic or surgical resection
    • Type 3 (sporadic): Radical resection with regional lymphadenectomy 1

  • Duodenal carcinoids:

    • Endoscopic resection if feasible
    • Transduodenal local excision with/without lymph node sampling
    • Pancreatoduodenectomy for larger tumors 1

  • Small intestinal/colon carcinoids:

    • Surgical resection of bowel with regional lymphadenectomy
    • Careful examination of entire bowel for multiple synchronous lesions 1

  • Appendiceal carcinoids:

    • Tumors <1 cm: Simple appendectomy is sufficient
    • Tumors 1-2 cm with aggressive features (lymphovascular/mesoappendiceal invasion): Consider right hemicolectomy
    • Tumors ≥2 cm: Right hemicolectomy with regional lymphadenectomy 1

  • Thymic carcinoids:

    • Surgical resection without adjuvant therapy
    • Consider radiation therapy after incomplete resection 1

  • Bronchopulmonary carcinoids:

    • Major lung resection or wedge resection plus node dissection 1

2. Advanced/Metastatic Disease

• Somatostatin analogs (SSAs):

  • First-line therapy for both symptom control and antiproliferative effects
  • Octreotide LAR 20-30 mg IM every 4 weeks
  • Controls symptoms in 65-72% of patients 1, 2, 3

• Liver-directed therapies for liver-dominant disease:

  • Surgical resection of liver metastases when feasible
  • Transarterial chemoembolization (TACE)
  • Radiofrequency ablation (RF) 1, 2

• Peptide receptor radionuclide therapy (PRRT):

  • Option for patients with tumors showing strong somatostatin receptor expression 1, 2

• Cytotoxic chemotherapy:

  • Limited efficacy in well-differentiated carcinoids
  • Temozolomide has shown clinical benefit
  • Cisplatin/etoposide combination for high-proliferating tumors 1

• Targeted therapy:

  • Everolimus has shown preliminary efficacy for progressive disease 1

Management of Carcinoid Syndrome

• Somatostatin analogs are the gold standard for controlling carcinoid syndrome symptoms:

  • Octreotide or lanreotide as first-line therapy
  • Dose escalation or increased frequency for refractory symptoms 1, 3, 4

• Telotristat ethyl:

  • For diarrhea refractory to somatostatin analogs 4

• Prevention of carcinoid crisis:

  • Prophylactic octreotide before invasive procedures:
    • IV bolus of 100-200 μg followed by continuous infusion of 50 μg/h during procedure
    • Continue infusion for 24 hours post-procedure 1, 2
  • Avoid drugs that release histamine or activate sympathetic nervous system 1

• Cardiac monitoring:

  • Echocardiography at diagnosis and during follow-up to assess for carcinoid heart disease 2

Follow-up Recommendations

• Typical carcinoid (TC):

  • CT at 3 and 6 months, then annually for 2 years
  • Chromogranin A measurements every 3-6 months
  • Annual chest X-ray and biochemistry profile long-term
  • Somatostatin receptor scintigraphy at 12 months and then only if recurrence suspected 1

• Atypical carcinoid (AC):

  • CT at 3 months post-surgery, then every 6 months for 5 years
  • Biochemical markers every 6 months
  • Annual CT after 5 years 1

Important Considerations

• Carcinoid tumors are generally slow-growing but can be aggressive depending on location, size, and histological features 5, 6

• Even with metastatic disease, long-term survival is possible with appropriate management 7, 6

• Consider prophylactic cholecystectomy if long-term somatostatin analog therapy is anticipated due to increased risk of gallstones 1

• The multidisciplinary approach is essential for optimal management of these complex tumors 6