How are carcinoid syndrome symptoms controlled?
The most troublesome symptoms patients with carcinoid syndrome experience are intense flushing and secretory diarrhea. Long-acting somatostatin analogues (octreotide, lanreotide) are the most effective available medications for controlling these carcinoid symptoms because approximately 80% of NETs express somatostatin receptors. Recommended starting doses are intramuscular octreotide LAR 20 to 30 mg every 4 weeks (with eventual dose escalation up to 60 mg every 4 weeks) or lanreotide 60 to 120 mg every 4 weeks. Short-acting octreotide can be used to treat intermittent breakthrough symptoms at doses of 100 to 500 mcg, as needed, every 8 hours. Positive somatostatin receptor–based functional imaging (see above) predicts a good response to these somatostatin analogues, but the necessity for positive imaging before starting these agents has not been established. In addition to symptom control, there is evidence that somatostatin analogues may have direct effects to inhibit tumor growth.