How is carcinoid syndrome treated?
There are a variety of carcinoid syndrome treatments, including somatostatin analogs and other medications, liver-directed therapies, surgery, and chemotherapy.
Medications for carcinoid syndrome treatment
Somatostatin analogs
Somatostatin is a naturally occurring hormone produced in the body. The function of somatostatin is to inhibit (reduce or limit) the release of gastrointestinal and endocrine hormones in the body, some of which are substances (e.g., serotonin) that contribute to carcinoid syndrome. A somatostatin analog is a medication that mimics the function of somatostatin and can reduce the production and release of substances by tumors that cause carcinoid syndrome.1 Somatostatin analogs include Octreotide and Lanreotide. 2,3
- Octreotide is available as a short-acting medication that is administered daily by injection just beneath the skin (subcutaneous injection). Octreotide is also available as a long-acting medication. The long-acting form of Octreotide is called Sandostatin LAR and can be administered monthly as an intramuscular injection.
- Lanreotide, also called Somatuline Depot, is another long-acting somatostatin analog that is also administered monthly.
Both Octreotide and Lanreotide have similar effectiveness and provide symptom relief in 50% to 70% of people with carcinoid syndrome.3 Additionally, multiple studies have indicated that both Octreotide and Lanreotide inhibit the growth of tumor cells.3
Common side effects include nausea, abdominal bloating, and fatty stools (steatorrhea). People taking these drugs may also experience gallstone formation and associated complications. Somatostatin, and thus somatostatin analogs, reduce the motility and contraction of the gallbladder which can occasionally cause gall-stone formation.3
Targeted therapy
Oral medications that act upon specific cell signaling pathways (such as mTOR, VEGF, VEGF-A) may be used in combination with other approaches to treat carcinoid syndrome.5
Telotristat
Telotristat is a recently approved drug that reduces the production of serotonin in the body. The drug is used in combination with a somatostatin analog to control diarrhea associated with carcinoid syndrome.2
Interferon
Interferons are substances that are produced naturally in the body. Interferon alfa may be used in combination with a somatostatin analog (e.g., Octreotide) to control symptoms of carcinoid syndrome that are difficult to or cannot be controlled with a somatostatin analog alone.2
Surgery for carcinoid syndrome treatment
Surgical treatments aim to remove or reduce the volume of NETs, causing carcinoid syndrome. Surgery is generally reserved for patients in which 90% of the tumor can be removed and who do not have compromised liver function or extensive liver metastases.2 The table below describes surgical treatments based on tumor type and location.