Carcinoid Tumors

1
Carcinoid Tumors

• Arise from enterochromaffin cells of the GI tract
  (including foregutlungs, bronchi and stomach,
  midgutsm. intestine, appedix, proximal colon,
  and hindgutdistal colon, rectum, GU)
• Histologic characteristics are based on special
  stains, typical vs. atypical features
• Benign vs. Malignant metastatic pattern of
  spread (as opposed to histology alone)

2
Carcinoid

• Appendix most common neoplasm found at path,
  usually younger pt, asymptomatic, can cause
  obstruction? appy. Less than 2 cm unlikely to
  have mets.
• Small intestine located terminal ileum, age
  60s-70s, abd pain due to mechanical obstruction
  or mesenteric ischemia
• Colon age 70s, abd pain or weight loss,
  usually right colon/cecum
• Rectum age 60s-70s, rectal bleeding or pain

3
Carcinoid

• Stomach type 1assoc. with atrophic gastritis
  and pernicious anemia. High levels of gastrin
  stimulate the enterochromaffin cells to transform
  into carcinoid.
• Stomach type 2in association with gastrinomas
  or MEN I.
• Both of these are indolent, rarely metastasize.

4
Carcinoid of the Lung

• A neuroendocrine tumor, arises from Kulchitskys
  cells within the bronchial mucosa usually
  perihilar
• Age 50s, cough, hemoptysis, recurrent
  pneumonia, chest pain.
• Paraneoplastic syndromes cushings, acromegaly,
  carcinoid (less than 5 of pts)
• Usu. indolent in lt15 of cases can met to nodes,
  liver, bone, skin

5
Carcinoid Syndrome

• Rare manifestation 10
• Tumors produce histamine, serotonin, kallikrein,
  and prostaglandins
• Symptoms abdominal pain, diarrhea, flushing,
  edema (increased vascular permeability),
  wheezing, tryptophan deficiency (dermatitis,
  glossitis, mental confusion)
• With intestinal carcinoiddoes not occur without
  mets to liver bronchial can cause the syndrome
  in absence of mets

6
Other manifestations

• Cardiac right sided valvular lesions (fibrous
  deposits)
• Fibrosis in the retroperitoneum or other sites
• Gastric carcinoid variant histamine mediated,
  results in hives also PUD
• Bronchial carcinoid variant prolonged flushing
  (days) with wheezing, periorbital edema,
  lacrimation, salivation, hypotension, tachycardia