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Carcinoid Tumor
Aka: Carcinoid Tumor, Carcinoid Syndrome, Malignant Carcinoid, Carcinoid, Thorson-Bioerck Syndrome, Argentaffinoma Syndrome, Flush Syndrome, Cassidy-Scholte Syndrome
- Epidemiology
- Prevalence: 1-2 per 100,000
- Age at presentation: 50-60 years
- Pathophysiology
- Carcinoid Tumor originates from gastrointestinal tract
- Embryonic foregut derivatives
- Lungs or Bronchi (23%)
- Stomach (7%)
- Embryonic midgut derivatives
- Ileum source (25%)
- Appendix (12%)
- Embryonic hindgut derivatives
- Distal colon (7%)
- Rectum (26%)
- Malignant neoplasms of enterochromaffin cells
- Excessive Serotonin (5-HT)
- Excessive Tachykinins (Substance P)
- Causes Flushing
- Excessive Histamine may occur
- May also be responsible for Flushing
- Metastases
- Most common sources of metastases
- Colon (more than two thirds at diagnosis)
- Small Intestine (most at diagnosis)
- Rectal sources (most if >2 cm tumor)
- Most common metastatic sites
- Liver
- Lung
- Classification (WHO, where PI is proliferation index)
- Well-Differentiated endocrine tumor (PI <2%)
- Well-Differentiated endocrine carcinoma (PI 2-15%)
- Poorly differentiated endocrine carcinoma (PI >15%)
- Presentations of Carcinoid Tumor
- Incidental asymptomatic Carcinoid Tumor (most common)
- Vague non-specific symptoms
- Diagnosis often delayed for up to 1 decade
- Abdominal Pain or Bowel Obstruction may occur
- Carcinoid Syndrome (occurs in 10% of Carcinoid Tumors)
- Late finding for Carcinoid Tumor
- Metastases are usually present when occurs
- Associated with midgut tumors (appendix, ileum)
- See related symptoms below
- Symptoms: Carcinoid Syndrome
- Intermittent migratory Flushing of head and neck skin
- Most common symptom
- Rapid color changes between red, white, and violet
- Symptoms accompanying Flushing episodes
- Explosive Diarrhea
- Nausea and Vomiting
- Abdominal Pain or cramping
- Bronchoconstriction
- Symptoms with prolonged Flushing attacks
- Lacrimation
- Periorbital edema
- Provocative
- Exertion
- Tyramine vasoactive amines (blue cheese, chocolate)
- Alcohol
- Signs
- Cardiovascular Changes
- Thickening of endocardium (valves, chambers)
- Tricuspid insufficiency
- Pulmonary stenosis
- Right Heart Failure
- Hypotension
- Telangiectasia
- Intestinal hypermotility (borborygmi)
- Differential Diagnosis of Flushing
- Systemic Mastocytosis
- Idiopathic Anaphylaxis
- Alcohol ingestion
- Post-Menopause
- Hyperthyroidism
- Vipoma
- ThyroidMedullary carcinoma
- Labs
- 24 hour Urine 5-hydroxyindoleacetic acid (5-HIAA)
- High false positive and false negative rate
- Serum Chromogranin A
- Test Sensitivity: 80%
- Test Specificity: 95%
- False positives in Multiple Myeloma
- Imaging: CT Abdomen or MRI Abdomen
- Indicated for abdominal symptoms
- Carcinoid Tumor appearance on imaging
- Mucosal thickening
- Submucosal mass
- Bowel lumen narrowed
- Spiculated mass (if infiltrated)
- Imaging: Neuroendocrine tumor localization
- Indium-111 labeled Octreotide Scan (preferred)
- Somatostatin receptor scintigraphy
- Test Sensitivity: 60%
- Test Specificity: 90%
- I-Labeled Meta-iodobenzylguanidine (MIPG)
- Positron Emission Tomography (PET Scan)
- Management: Options vary depending on presentation
- Octreotide 75 to 150 ug up to 750 ug q8 hours
- Indications: Flushing
- Adverse: Hypoglycemia, Steatorrhea, Cholelithiasis
- Alpha-Interferon
- Possibly efficacious as adjunctive therapy
- Antihistamines
- May be useful in histamine-related tumors
- Surgery
- Excision of primary tumor
- Tumor debulking
- Complications
- Second Primary Malignancy (in up to 46% of Carcinoids)
- Gastrointestinal and Genitourinary tumors
- Lung and Bronchial cancers
- Prognosis
- Five year survival: 67% (variable based on type)
- Modlin (2003) Cancer 97:934-59
- Resources
- Carcinoid Cancer Foundation, Inc
- http://www.carcinoid.org
- References
- Abeloff (2000) Clinical Oncology, p. 1379-81
- Dumbro (1999) 5 Minute Clinical Consultant, p. 1192
- Goldman (2000) Cecil Textbook Medicine,p.1295-7
- Kulke (1999) N Engl J Med 340:858-68
- Robertson (2006) Am Fam Physcian 74:429-34