Carcinoid tumor

Carcinoid tumors are a type of neuroendocrine tumor that can occur in a number of locations. Carcinoid tumors arise from endocrine amine precursor uptake and decarboxylation (APUD) cells that can be found throughout the gastrointestinal tract as well as other organs (e.g. lung). In general, they are slow growing tumors but are nevertheless capable of metastasizing.

  • can be variable, dependent on the location:
    • carcinoid tumors involving the jejunum and ileum can be large at presentation but are usually found incidentally
    • rectal carcinoids may cause pain
    • gastrointestinal tract carcinoid can present as vague abdominal pain
  • carcinoid syndrome: in 8% of patients with a carcinoid tumor 9
  • 5-HIAA (5-hydroxyindoleacetic acid): usually suggests a functioning carcinoid tumor
  • chromogranin A (CgA): considered a valuable tool in the diagnosis of neuroendocrine neoplasia in general 6

Refer to specific articles (above) for imaging characteristics.

  • indium-111 octreotide (Octreoscan) will concentrate in gastrointestinal tract carcinoid tumors as well as in liver metastases, and is generally considered the test of choice due to its high sensitivity 14
  • iodine-123 MIBG will also concentrate in carcinoid tumors, including the low percentage (~15%) that are negative with indium-111 octreotide 13
  • gallium-68 octreotide PET scan: usually avid

It was initially coined by Oberndorfer in 1907 as “karzinoide” to denote its resemblance to carcinoma 4.

Share article

Article information

rID: 9528
Synonyms or Alternate Spellings:
  • Carcinoid tumours
  • Carcinoid tumour general
  • Carcnoid tumor
  • Carcinoid tumour (general)
  • Carcinoid tumors

Support Radiopaedia and see fewer ads

Cases and figures

  • Figure 1: gross pathology - terminal ileal carcinoid
    Drag here to reorder.
  • Case 1: on octreotide scan
    Drag here to reorder.
  • Figure 2: histological appearance
    Drag here to reorder.
  • Follow up
    Case 2: bronchial carcinoid with hepatic metastasis
    Drag here to reorder.
  • Case 3: gastric carcinoid
    Drag here to reorder.
  • Case 4: intestinal carcinoid
    Drag here to reorder.
  • Case 5: jejunal carcinoid
    Drag here to reorder.
  • Case 6: involving terminal ileum
    Drag here to reorder.
  • Case 7: mesenteric carcinoid with hepatic and nodal metastases
    Drag here to reorder.
  • Case 8: with liver metastases
    Drag here to reorder.
  • Case 9: primary hepatic carcinoid
    Drag here to reorder.
  • Case 10: terminal ileum carcinoid
    Drag here to reorder.
  • Case 11: mesenteric carcinoid
    Drag here to reorder.
  • Case 12: MRI
    Drag here to reorder.
  • Case 13: small bowel carcinoid
    Drag here to reorder.
  • Case 14: ileal carcinoid with orbital metastases
    Drag here to reorder.
  • Case 15
    Drag here to reorder.
  • Case 16: with liver metastases
    Drag here to reorder.
  • Case 17
    Drag here to reorder.
  • Case 18
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.