A carcinoid, also called a carcinoid tumor, is a rare, slow-growing cancer of the neuroendocrine system. This system furnishes hormones that govern organ function throughout the body. According to Macmillan Cancer Support, 85 percent of carcinoids occur in the gastrointestinal system, specifically the appendix and the small intestine. They begin in the cells that produce hormones needed for the regulation of the muscles that move food through the stomach and small intestine and for the control of digestive enzymes.
Surgery
According to the American Society of Clinical Oncology, surgery is an important part of the treatment for carcinoid tumors, where a surgical oncologist tries to remove the entire tumor along with some surrounding normal tissue. For gastrointestinal carcinoid tumors, the surgeon uses a skin incision to access and remove the tumor, or it may be possible to use an endoscope which is a flexible tube with a light and a camera that the surgeon runs down the patient's esophagus into the stomach and small intestine. Carcinoids that have metastasized, or progressed, to the liver can be removed by liver resection in which the affected part of the liver is excised. The surgeon may also destroy liver metastases by using a CT scan to guide the injection of ethanol directly into the tumors. Blocking the flow of blood into the liver by a procedure called hepatic artery occlusion may also be an effective surgical method of eradicating liver metastases.
Chemotherapy
Systemic chemotherapy is a treatment in which the patient takes anti-cancer drugs either orally or intravenously, and the drugs travel through the blood to all parts of the body to kill cancer cells, according to the National Cancer Institute. In regional chemotherapy, the patient receives the anti-cancer drugs in a specific part of the body such as the spinal column, an organ or the abdominal cavity. Single-drug therapies include fluorouracil, doxorubicin and dacarbazine; a three-drug combination regimen consisting of cyclophosphamide, fluorouracil and streptozocin.
For cases of carcinoid tumors that have metastasized to the liver, a type of regional chemotherapy called chemoembolization may be useful, says the National Cancer Institute. In this treatment, doctors inject fluorouracil, doxorubicin, mitomycin or cisplatin along with a substance like collagen fibers into the main artery of the liver. The collagen fibers block the artery and most of the anti-cancer drugs remain near the liver metastases with only a small amount going to other parts of the body. Because the hepatic artery is blocked, the tumor can't get enough oxygenated blood to grow and survive.
Radiation Therapy
Doctors may elect to use X-rays or other high-energy radiation to kill the cells of the gastrointestinal carcinoid tumor, says the National Cancer Institute. In external radiation therapy, the patient receives the radiation from a machine outside the body. Internal radiation therapy involves the surgical placement of a radioactive substance either directly into the carcinoid tumor or somewhere very close to it. The substance is sealed inside seeds, needles, wires or catheters.
