Carcinoid Tumors Flashcards
what is a carcinoid tumor?
tumor arising from neuroendocrine cells
- Kulchitsky cells
- secrete serotonin
what are the common sites
Appendix
Ileum
Rectum
Bronchus
what are the signs/symptoms
depends on location
most cases are asymptomatic
SBO, abdominal pain, bleeding, weight loss, diaphoresis, pellagra skin changes, intussusception. carcinoid syndrome, wheezing
why SBO with carcinoid?
classically = severe mesenteric fibrosis
what are the pellagra-like sympotms
3Ds
- Dermatitis
- Diarrhea
- Dementia
what causes pellagra in carcinoid patients
decreased niacin production
what is carcinoid syndrome
B FDR
- Bronchospasm
- Flushing (skin)
- Diarrhea
- Right-sided heart failure (from valve failure)
why does right sided heart failure develop but not left sided heart failure?
lungs act as a filter
classic cardiac complication with carcinoid syndrome
Tricuspid insufficiency
pulmonary stensosis
what released substances cause carcinoid syndrome
serotonin and vasoactive peptides
what is the medical treatment for carcinoid syndrome
octreotide IV
what is the medical treatment of diarrhea alone
ondansetron - serotonin antagonist
how does the liver prevent carcinoid syndrome
degradation of serotonin and other vasoactive peptides when the tumor drains into he portal vein
why does carcinoid syndrome occur in some tumors but not in others
occurs when venous drainage from the tumor gains access to the systemic circulation by avoiding hepatic degradation of the vasoactive substances
what tumors can produce carcinoid syndrome
liver metastases
retroperitoneal disease draining in tparavertebral veins
primary tumor outside the GI tract, portal venous drainage (testicular
