On the basis of stages, treatment of localized carcinoid tumors is based mostly on their size. Experts sometimes disagree on the exact size cutoffs for making treatment decisions, and there are some “gray zones” of size where it has not been determined exactly what treatment is best.

Stomach: Small carcinoid tumors of the stomach can often be completely removed through an endoscope. For those larger than 1 centimeter (slightly less than 1/2 inch), an incision in the abdomen may be needed to remove the tumor and some surrounding stomach tissue. In some patients, the growth of stomach neuroendocrine tumors may be fueled by gastrin, a hormone made by cells of the antrum of the stomach (the part next to the small intestine). In these patients, doctors may advise removing the antrum.

Small intestine: Local excision is the usual treatment for carcinoid tumors in the small intestine that are smaller than 1 centimeter (slightly less than 1/2 inch). Surgery for larger tumors involves taking more surrounding tissue, as well as some surrounding blood vessels and lymph nodes.

Large intestine (other than appendix and rectum): The usual treatment is local excision. If the carcinoid tumor is smaller than 1 centimeter, this can often be done through a colonoscope. If the tumor is larger, surgery usually involves an incision through the skin.

Appendix: Nearly all cancer specialists agree that an appendectomy (surgical removal of the appendix) is the only treatment needed for carcinoid tumors that are smaller than 1.5 centimeters (slightly larger than 1/2 inch).

For tumors between 1.5 and 2 centimeters, most doctors believe that removing the appendix is all that is needed. But they also consider other factors, such as the patient’s age, general health, and the patient’s degree of worry about the possibility of the cancer coming back, to determine whether more treatment is needed.

Rectum: Rectal carcinoid tumors that are smaller than 1 centimeter (slightly less than 1/2 inch) are usually treated by fulguration (destroying the cancer by burning it with an electrical current) or local excision.

For rectal carcinoid tumors between 1 and 2 centimeters, the best approach is often determined by how deeply the carcinoid tumor invades the wall of the rectum, as well as other details of each patient’s medical situation.

Pancreas: The pancreas is a major gland that sits behind the stomach. It is attached at its head to the small intestine, where it releases substances that aid in digestion. It also makes several important hormones that it secretes into the bloodstream.

Localized islet cell tumors are potentially curable with surgery. Those in the distal (far) end of the pancreas are usually managed with a distal pancreatectomy. The spleen is usually removed as well. Occasionally, patients who have tumors in the head of the pancreas that are causing digestion problems will require a pancreaticoduodenectomy (Whipple procedure). This operation removes the head of the pancreas and sometimes removes the body of the pancreas as well.

Regional Spread

If possible, the primary tumor/cancer and areas of spread to adjacent tissues and lymph nodes should all be removed by surgery. If this can’t be done, surgery should remove as much cancer as possible without causing severe side effects. Surgery should also be done to relieve symptoms

Distant Spread

Cure in this situation is not usually possible, although treatment is not always needed right away, depending on how quickly the tumors are growing. The goal of surgery in this situation is to relieve symptoms and slow the course of the disease.

If carcinoid syndrome is causing bothersome symptoms, treatment options include chemotherapy, immunotherapy, treatment with octreotide, or removing the metastatic tumors by surgery. If metastatic tumors cannot be removed without causing severe side effects, ablative methods can be used to destroy as much of the tumors as possible. These methods, used mostly for liver metastases, include chemoembolization, radiofrequency ablation, cryotherapy, and alcohol injection.

Recurrent Carcinoid Tumors

For tumors that come back after initial treatment, surgery to remove all signs of tumor should be done whenever possible, as it provides the best chance for a good long-term outcome. If surgery is not possible, the treatments described above for tumors that have spread to distant sites may be helpful.

Carcinoid Heart Disease

The substances released into the blood by some neuroendocrine tumors/cancers can damage the heart. The main treatment is with octreotide to block the cancer’s secretion of the toxic substances. Drugs (diuretics) to strengthen the heart beat and to get rid of fluid can also be helpful. In some instances, heart surgery may be needed to replace the damaged valves.