Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started
My Medicine

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

Cancer Health Center

Font Size

Gastrointestinal Carcinoid Tumors Treatment (PDQ®): Treatment - Health Professional Information [NCI] - General Information About Gastrointestinal Carcinoid Tumors



A promising approach for positron emission tomography (PET) as an imaging modality to visualize GI carcinoids appears to be the use of the radioactive-labeled serotonin precursor 11C-5-hydroxytryptophan (11C-5-HTP). With 11C-5-HTP, tumor detection rates have been reported to be as high as 100%, and some investigators have concluded that 11C-5-HTP PET should be used as a universal detection method for detecting NETs.[57,58,59] In one study of NETS, including 18 patients with GI carcinoids, 11C-5-HTP PET detected tumor lesions in 95% of patients. In 58% of cases, 11C-5-HTP PET detected more lesions than SRS and CT, compared with the 7% that 11C-5-HTP PET did not detect.[59] Other imaging approaches have been investigated using technetium-labeled isotopes, combining CT/MRI with 18F-DOPA PET, combining 131 MIBG with 111In-octreotide, and coupling the isotopes 68Ga and 64Cu to octreotide.[26]


Endoscopic ultrasonography (EUS) may be a sensitive method for the detection of gastric and duodenal carcinoids and may be superior to conventional ultrasound, particularly in the detection of small tumors (2 mm-3 mm) that are localized in the bowel lumen.[60,61] In one study, the EUS was reported to have an accuracy of 90% for the localization and staging of colorectal carcinoids.[62]


The development of CE in the diagnosis of GI carcinoids is nascent, although this technique may prove useful in the detection of small bowel carcinoids.[63]


Double-balloon enteroscopy is a time-consuming procedure that is being studied in the diagnosis of small bowel tumors, including carcinoids.[64,65] It is usually performed under general anesthesia, although it can be done under conscious sedation.


MRI angiography has replaced angiography to a large extent. However, selective and supraselective angiography may be useful to:

  • Demonstrate the degree of tumor vascularity.
  • Identify the sources of vascular supply.
  • Delineate the relationship of the tumor to adjacent major vascular structures.
  • Provide information regarding vascular invasion.

Angiography may be useful as an adjunct to surgery, particularly in the case of large invasive lesions in proximity to the portal vein and superior mesenteric artery. Overall, this imaging technique provides a more precise topographic delineation of the tumor or tumor-related vessels and facilitates resection.[26]

1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10
Next Article:

Today on WebMD

Colorectal cancer cells
New! I AM Not Cancer Facebook Group
Lung cancer xray
See it in pictures, plus read the facts.
sauteed cherry tomatoes
Fight cancer one plate at a time.
Ovarian cancer illustration
Real Cancer Perspectives
Jennifer Goodman Linn self-portrait
what is your cancer risk
colorectal cancer treatment advances
breast cancer overview slideshow
prostate cancer overview
lung cancer overview slideshow
ovarian cancer overview slideshow
Actor Michael Douglas