In this section, you will find information about these treatments, including:
- Surgical Debulking
- Hepatic Artery Embolization, Chemoembolization, or Ligation
- Medical Therapy
- Radiotherapy
Surgical Debulking
For patients with carcinoid syndrome, surgical debulking of tumors can decrease the amount of hormones being produced by tumor cells. For some patients, this may provide some relief of symptoms. However, since surgeons are unable to remove all metastatic tumor presence, signs and symptoms of carcinoid syndrome may remain, or may return as the remaining tumor grows. Cryosurgery may sometimes be used to destroy carcinoid tumor cells in the liver when it is not possible to remove them surgically1,2,3.
Surgery can also be used to relieve intestinal obstructions caused by tumors, which may relieve abdominal pain, bleeding, or other symptoms. Some patients with cardiac disease may have surgery for valve replacement3,4.
Hepatic Artery Embolization, Chemoembolization, or Ligation2,3,5
Another means of debulking tumor presence in the liver is to cut off the supply of blood and oxygen required for tumor growth. The rationale behind this approach is that the portal vein provides 75% to 80% of the blood supply to normal liver cells, while the hepatic artery only provides 20% to 25% of the normal blood supply. In contrast, the hypervascularity of hepatic neoplasms results in their deriving almost all of their blood supply from the hepatic artery. Thus, occluding a hepatic artery will cause tumor necrosis while preserving most of the normal liver cells. In practice, this may be accomplished by injecting a hepatic artery with embolic material (which obstructs the vessel with a clot or foreign substance) or by surgical ligation of a hepatic artery. However, in time new blood vessels develop, which restores circulation to the remaining tumor cells.
In some cases, hepatic artery embolization is accompanied by the administration of chemotherapy agents. The chemotherapy acts directly to destroy tumor cells in the liver. And, by administration into a hepatic artery, chemotherapy agents are present in reduced quantities in other areas of the body and, therefore, cause a reduced incidence of toxic effects.
Medical Therapy
Octreotide Acetate
Octreotide acetate therapies such as Sandostatin® LAR Depot (octreotide acetate for injectable suspension) block the release of bioactive substances from carcinoid tumors. Also, like somatostatin, Sandostatin® LAR Depot exerts direct effects on the gastrointestinal tract itself; it prolongs intestinal transit time. By doing so, it can significantly reduce symptoms (notably, diarrhea and flushing) that are associated with excess quantities of these bioactive substances2,6).
Sandostatin® LAR Depot builds on the established efficacy of octreotide acetate by adding the convenience of a long-acting release formulation. Sandostatin® LAR Depot is administered monthly, rather than daily7:
- Sandostatin® LAR Depot incorporates octreotide into microspheres of the biodegradable glucose star polymer, D,L-lactic and glycolic acids copolymer
- Slow drug release accompanies the biodegradation of the polymer ester bond through hydrolysis
- The short-acting formulation can be used for additional control of symptom flare ups
Find out more about:
Interferon-α
Interferon-α has been shown to reduce hormone production from carcinoid tumors. In about half to two-thirds of patients in clinical trials, this has been accompanied by reduction in symptoms. In a few patients, interferon-α has also reduced tumor size8,9. (In several small trials, response rates ranged from 0% to 20%.)
Interferon-α is usually administered 3 times a week, in doses of approximately 3 to 9 million units given by subcutaneous injection. Most patients experience flu-like symptoms (fever, fatigue) for a few days after administration. Other side effects, including weight loss and anemia have also been noted2,9.
Chemotherapy2,10
During the 1970s and 1980s, chemotherapy was frequently used to try to reduce the growth of primary and metastatic carcinoid tumors. However, since chemotherapy typically produced poor results (with partial responses in no more than 10% to 20% of patients) and was associated with significant toxicity, chemotherapy now has a greatly reduced role.
Some chemotherapy regimens that have been used for the treatment of carcinoid tumors and VIPomas include2,9:
- 5-fluorouracil and streptozocin
- Cyclophosphamide, doxorubicin, 5-fluorouracil, and streptozocin
- Dacarbazine, 5-fluorouracil, epirubicin
- Etoposide and cisplatin
Radiotherapy
Radiation therapy may be used to address specific symptoms (eg, pain resulting from bone metastasis) that may be present in certain patients with carcinoid syndrome. However, it is not useful in treating metastases in the liver or other nonskeletal tissues2,9.
Important Safety Information
Carcinoid Syndrome:
Sandostatin® LAR Depot (octreotide acetate for injectable suspension) is indicated for long-term treatment of the severe diarrhea and flushing episodes associated with metastatic carcinoid tumors and for the long-term treatment of the profuse watery diarrhea associated with VIP-secreting tumors in patients in whom initial treatment with immediate release Sandostatin® (octreotide acetate) Injection has been shown to be effective and tolerated.
Important Safety Information:
As with immediate release Sandostatin® Injection, the most frequently reported drug-related adverse events were biliary disorders (62%), gastrointestinal disorders (14% to 38%), and injection-site pain (20% to 50%). Hypoglycemia (4%), hyperglycemia (27%), sinus bradycardia (19%), conduction abnormalities (9%), and arrhythmias (3%) have been reported.
The controlled clinical trials that support the marketing clearance for Sandostatin® LAR Depot did not include determination of effect on tumor size or rate of growth. Sandostatin® LAR Depot is not indicated for tumor shrinkage.
Acromegaly
Sandostatin® LAR Depot (octreotide acetate for injectable suspension) is indicated for long-term maintenance therapy in acromegalic patients who have had an inadequate response to surgery and/or radiotherapy, or for whom surgery and/or radiotherapy is not an option. The goal of treatment in acromegaly is to reduce GH and IGF-1 levels to normal.
Important Safety Information:
As with immediate release Sandostatin® Injection, the most frequently reported drug-related adverse events were biliary disorders (52%), gastrointestinal disorders (7% to 36%), and injection-site pain (2% to 11%). Hypoglycemia (2%), hyperglycemia (15%), and hypothyroidism (2%) have been reported. While not measured in acromegalic patients receiving Sandostatin® LAR Depot, ECG changes have been reported in patients receiving immediate release Sandostatin® Injection; the degree to which these abnormalities are related to octreotide acetate is not clear, as many acromegalics have cardiovascular disease. You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.
