[Rectal neuroendocrine tumors: endoscopic therapy]

Area of Science:

• Gastroenterology
• Oncology
• Surgical Oncology

Background:

• Clinically detected neuroendocrine neoplasms of the rectum show a significant increase in incidence in Germany.
• Screening colonoscopies lead to earlier diagnosis of rectal neuroendocrine tumors, improving prognosis.

Purpose of the Study:

• To outline the diagnostic and management strategies for rectal neuroendocrine neoplasms.
• To discuss the current treatment approaches based on tumor size, infiltration, and patient characteristics.

Main Methods:

• Endoscopic ultrasonography is crucial for tumor staging, assessing size, depth of infiltration, and lymph node metastasis.
• Treatment decisions are guided by tumor size, presence of vascular invasion, lymph node involvement, and patient's age and comorbidities.

Main Results:

• Well-differentiated neuroendocrine tumors ≤10 mm without muscularis propria invasion are candidates for endoscopic resection.
• Surgical lymph node dissection is indicated for tumors with lymphatic/blood vessel invasion or lymph node spread.
• Management for tumors 10.1-20 mm is debated, balancing endoscopic approaches for older/multimorbid patients with surgical options for younger/fitter individuals.
• Neuroendocrine rectal neoplasms ≥20 mm have a high metastatic risk (60-80%), necessitating more aggressive management beyond endoscopic resection.

Conclusions:

• Rectal neuroendocrine neoplasms require tailored management based on precise staging.
• Early diagnosis through screening improves outcomes, but careful consideration of treatment modality is essential for optimal patient care.