Treatment of Appendiceal Neuroendocrine Tumor 1–2 cm, Grade G1, Without Lympho-vascular Invasion

This protocol addresses the clinical scenario of an appendiceal neuroendocrine tumor measuring between 1 and 2 cm in diameter, with confirmed grade G1 histology, tumor size below 15 mm, and no lympho-vascular invasion — a combination where management decisions require careful consideration of both low and residual metastatic risk.

Appendiceal neuroendocrine tumors in the 1–2 cm range (T2 by ENETS, T1b by UICC/AJCC staging) occupy a clinically important middle ground: lymph node or distant metastases are uncommon but remain possible. When grading is G1 and tumor size is less than 15 mm with no lympho-vascular invasion, this specific profile informs the extent of surgical planning.

For this defined combination — grade G1, size under 15 mm, and absent lympho-vascular invasion — a surgical intervention is the mainstay of management. The full protocol details which procedure is indicated and what follow-up, if any, is required beyond the initial surgery.