Treatment of Gastrointestinal Carcinoid Tumors by Stage
A tumor is localized when it is found only in the organ where it started. Treatment of localized carcinoid tumors is based mostly on their size. Experts sometimes disagree on the exact size for making treatment decisions, and there are some sizes where it has not been determined exactly what treatment is best.
Carcinoid tumors of the stomach are grouped by the level of a hormone called gastrin and the amount of acid in the stomach (measured before surgery). Certain conditions linked to high gastrin levels are also linked to getting many carcinoid tumors of the stomach. Patients with these conditions who have stomach carcinoid tumors are treated differently from patients without these conditions.
Type 1: Patients with high gastrin levels but low levels of stomach acid are said to have type 1 tumors. These carcinoid tumors tend to be small, but there may be many of them. The tumors don’t tend to grow into the deeper layers of the stomach or spread to other organs or tissues, and are often treated by removing them completely through an endoscope. The other option is to watch the tumors closely (by endoscopy), and only removing them if they start growing.
Type 2: Patients who have high gastrin levels and high stomach acid levels are said to have type 2 tumors. Like type 1 tumors they are often small and there may be more than one at a time. Type 2 tumors also don’t tend to grow into deeper layers of the stomach or spread to other organs. Small tumors can be watched closely without treatment, removed with endoscopy, or treated with a medicine like octreotide (Sandostatin) or lanreotide (Somatuline) that will lower both gastrin and stomach acid. For tumors larger than 2 cm (slightly less than an inch), just watching the tumor closely isn’t usually an option. These tumors need to be removed, either through an endoscope or in a regular operation through an incision in the abdomen that removes the tumor and some surrounding stomach tissue.
Type 3: Patients who don’t have high gastrin levels (and have normal levels of stomach acid) are said to have type 3 tumors. There is usually only one tumor, and the tumor tends to grow into deeper layers of the stomach or even spread to nearby lymph nodes or other organs (like the liver). If the tumor is small, endoscopic surgery may still be an option. More, often, though, more extensive surgery is needed: A piece of the stomach is removed (a partial gastrectomy) along with nearby lymph nodes.
Some small tumors in the duodenum (the first part of the small intestine) can often be removed through the endoscope (endoscopic resection). Depending on the size of the tumor and whether it is growing into nearby tissues, other options include surgery to remove the tumor (local excision), removing all or part of the duodenum with nearby lymph nodes, and removing the duodenum and part of the pancreas (a pancreatoduodenectomy).
For tumors in other parts of the small intestine, treatment is either local excision for small tumors or small bowel resection (removal of a piece of intestine as well as some surrounding blood vessels and lymph nodes) for larger tumors.
Large intestine (other than appendix and rectum)
The usual treatment is hemicolectomy (removal of a section of colon along with nearby lymph nodes and blood vessels). Because many patients have more than one carcinoid tumor, the surgeon will often check the rest of the colon for other tumors during surgery. For very small tumors, sometimes the tumor can be removed without surgery using a colonoscope.
Most often, an appendectomy (surgical removal of the appendix) is the only treatment needed for carcinoid tumors that are 2 cm (a little less than an inch) across or smaller. Still, other factors, such as the way the tumor cells look under the microscope, the patient's age, general health, and the patient's degree of worry about the possibility of the cancer coming back, might also be used to determine whether more treatment is needed.
Tumors larger than 2 cm are more likely to have already spread to nearby tissues and lymph nodes, so more extensive surgery is usually recommended for these tumors. This means removal of about a third of the colon next to the appendix (a hemicolectomy), along with nearby blood vessels and lymph nodes. This procedure might not be recommended for people who are older or have other serious health problems (especially if these problems make surgery more risky), because the benefit might not outweigh the risks.
Doctors check how deep the cancer is growing into the wall of the rectum before surgery by using endoscopic ultrasound (discussed in the section about diagnosis). Most rectal carcinoid tumors that are smaller than 2 cm (slightly less than an inch) can be removed through an endoscope or local excision through the anus.
The best approach for rectal carcinoid tumors between 1 and 2 cm, depends on how deeply the tumor has grown into the wall of the rectum, as well as other details of each patient's medical situation. If the tumor has grown into the thick muscle layer of the rectum (the muscularis propria) or deeper, it needs to be treated the same as a larger tumor.
Carcinoid tumors larger than 2 cm (and those that have grown deep into the wall of the rectum) have a higher risk of growing and spreading, so they are removed by the same operations used for adenocarcinomas (the usual type of rectal cancer). This operation is a low anterior resection if the carcinoid is in the upper part of the rectum. If the lower part is involved, abdominoperineal (AP) resection and colostomy are used.
Regional spread means that the cancer has either spread to nearby lymph nodes or it has grown through the wall of the organ where it started and has invaded nearby tissues such as fat, ligaments, and muscle.
If possible, the primary (main) tumor and any areas of cancer spread should all be removed by surgery. Nearby lymph nodes should be removed and checked for signs of cancer spread. This provides the best chance of cure. 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 such as intestinal blockage caused by the local growth of the tumor.
At this stage, a cure 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 usually to relieve symptoms and slow the course of the disease. For example, removing or bypassing areas blocked by cancer growth can relieve some symptoms. If distant metastases are not causing symptoms, treatment may not be needed, although chemotherapy or interferon-alfa may help delay symptoms in some patients. If the cancer has spread to the liver, even when it isn’t causing symptoms, some doctors recommend treatment with octreotide or lanreotide because it may slow tumor growth.
If carcinoid syndrome is causing bothersome symptoms, treatment options include chemotherapy, immunotherapy, treatment with octreotide or lanreotide, or surgery to remove the metastatic tumors. If metastatic tumors in the liver cannot be removed by surgery without causing severe side effects, ablation or embolization can be used to destroy as much of the tumors as possible. Patients should also be advised to avoid alcoholic drinks, stress, strenuous exercise, spicy foods, and certain medicines that can make the symptoms of carcinoid syndrome worse.
Recurrent carcinoid tumors
When cancer come backs after treatment it is called a recurrence. Recurrence can be local (in or near the same place it started) or distant (spread to organs such as the lungs or bone). Patients with recurrent carcinoid tumors are treated with surgery to remove all signs of tumor whenever possible. This provides the best chance for a good long-term outcome. If surgery is not possible, the treatments used for distant spread may be helpful.
Carcinoid heart disease
The substances released into the blood by some carcinoid tumors can damage the heart. Early symptoms are fatigue and shortness of breath. Eventually, patients get fluid in their legs and even their abdomen. The major cause is damage to the valves of the heart. Doctors can usually make the diagnosis by listening to the heart and by an ultrasound exam of the heart called an echocardiogram.
The main treatment is with a somatostatin analog like octreotide or lanreotide to block the cancer’s secretion of the toxic substances. Drugs (diuretics) to strengthen the heartbeat and to get rid of fluid can also help. In some instances, heart surgery may be needed to replace the damaged valves.
Last Medical Review: February 26, 2015 Last Revised: February 8, 2016