Rectal Neuroendocrine Neoplasms: Why Is There a Global Variation?

Area of Science:

• Gastroenterology
• Oncology
• Epidemiology

Background:

• Rectal neuroendocrine tumors (NETs) are a common gastrointestinal NET subtype with a documented increase in incidence over the past 30 years.
• These tumors represent 1-2% of all rectal cancers and are typically diagnosed in individuals aged 50-60.

Purpose of the Study:

• To review and analyze global variations in the incidence of rectal neuroendocrine tumors.
• To identify potential causative factors and epidemiological trends associated with rectal NETs.

Main Methods:

• Systematic review of published literature on the epidemiology of neuroendocrine tumors.
• Analysis of data from various methodologies examining NET incidence and prevalence.
• Inclusion of data from Surveillance, Epidemiology, and End Results (SEER) database for ethnic variations.

Main Results:

• Rectal NETs are frequently small (<10 mm), often discovered incidentally during colonoscopies or colon cancer screenings.
• The highest incidence rates are reported in individuals of Asian ethnicity, with a tenfold increase compared to white populations.
• Increased incidence is also noted in Black and Hispanic populations.

Conclusions:

• Rectal NETs are increasingly diagnosed, often incidentally and are typically small, favoring endoscopic resection.
• Significant ethnic variations in rectal NET incidence exist, warranting further investigation into underlying causes.
• Development of comprehensive cancer registries and research into ethnic disparities are crucial for future understanding and management.