Short Distal Resection Margin Does Not Increase Recurrence Risk After R0 Resection for Rectal Neuroendocrine Tumors:...

Area of Science:

• Gastroenterology
• Surgical Oncology
• Endocrinology

Background:

• The optimal distal resection margin (DRM) for rectal neuroendocrine tumors (NETs) is not well-defined.
• Aggressive resection for rectal NETs may negatively impact anorectal function.
• Rectal NETs are generally indolent, necessitating a balance between oncological control and functional preservation.

Purpose of the Study:

• To investigate the impact of shorter distal resection margins (DRMs) on recurrence risk in patients with rectal neuroendocrine tumors (NETs) undergoing curative resection.
• To determine if a shorter DRM influences oncological outcomes in rectal NET patients.
• To evaluate the safety of minimizing DRM in rectal NET surgery.

Main Methods:

• Retrospective study of 208 rectal NET patients undergoing total mesorectal excision (TME) between January 2005 and December 2023.
• Patients were divided into shorter DRM (≤10 mm) and longer DRM (>10 mm) groups.
• Clinicopathological data, recurrence patterns, and survival were compared; a fine-grey regression model identified recurrence predictors.

Main Results:

• No significant difference in overall recurrence rates between shorter DRM (6.6%) and longer DRM (6.0%) groups (p=1.000).
• No local recurrence was observed in either group.
• Tumor size >20 mm and NET G2 were independent risk factors for recurrence; shorter DRM was not.

Conclusions:

• A shorter distal resection margin (DRM) appears oncologically safe for rectal NETs when R0 resection is achieved.
• Minimizing DRM may allow for more function-preserving surgery, particularly for rectal NET G1/G2.
• Prioritizing oncological radicality while considering functional outcomes is crucial in rectal NET management.