Carcinoid Tumors / Neuroendocrine Tumors of the Small Bowel – Etiology / Pathogenesis


  • Carcinoid tumors are classically defined as:
    • Well-differentiated:
      • Low- to intermediate-grade neuroendocrine tumors:
        • Traditionally:
          • High-grade or poorly differentiated neuroendocrine tumors are classified as:
            • Neuroendocrine carcinomas:
              • Although many refer to any small bowel neuroendocrine tumor as:
                • A carcinoid tumor:
                  • Which is the term I favor
  • Carcinoid tumors:
    • Arise most commonly from:
      • The gastrointestinal (GI) tract:
        • But can also arise in the:
          • Lungs
        • Other rare additional sites:
          • Such as the genitourinary system
    • Within the GI tract:
      • Carcinoid tumors most commonly arise from the:
        • Small bowel (45%)
        • Rectum (20%)
        • Appendix (17%):
          • This data is based on a Survival, Epidemiology, and End Results (SEER) database report from 1973 to 1997:
            • Although rectal carcinoids are becoming more common:
              • Since the advent of screening colonoscopy
    • Epidemiology:
      • The annual incidence of newly diagnosed small bowel carcinoid tumors:
        • Is 9.3 per million:
          • Although the true incidence may be higher based on postmortem studies
      • However, the significance of early-stage and extremely low-grade preclinical carcinoid tumors is:
        • Unknown
      • Carcinoid tumors are:
        • The most common small bowel malignancies:
          • Slightly more common than adenocarcinomas:
            • 37.4% versus 36.9%
        • Their incidence has been rising by:
          • An average of 3.6% annually:
            • Over the past 30 years
      • They are slightly more common in men than in women:
        • 52% versus 48%
      • Te median age at diagnosis is:
        • 66

#Arrangoiz #CancerSurgeon #SurgicalOncologist #Teacher #Surgeon #CancerExpert

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s