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SEER Inquiry System - Report
Produced: 11/16/2025 1:31 AM
Question 20230074
Inquiry Details
References:
SEER EOD. SEER*RSA, v3.0-NET Jejunum and Ileum
Question:
Extent of Disease/EOD Regional Nodes--Small Intestine: For an ileal/jejunal neuroendocrine primary, how should mesenteric soft tissue deposits (less than 2 cm) be collected in Extent of Disease (EOD) Staging? See Discussion.
Discussion:
Example: Patient is diagnosed with grade 1 well-differentiated neuroendocrine tumor of the ileum, confirmed on ileocolic resection in 2023. The final diagnosis is a 2.8 cm ileal mass, with focal lymph-vascular invasion and a single 0.6 cm tumor deposit within mesenteric fat; primary tumor completely resected with widely negative margins and 10 regional nodes negative for malignancy.
According to AJCC, mesenteric masses less than 2 cm should be stated in the pathology report as being present and collected by registrars but do not affect stage. EOD Regional Nodes has a code for large mesenteric masses greater than 2 cm only. How should we record these smaller tumor deposits if they are not supposed to affect stage?
Answer:
Do not code 500 for involvement of the mesentery unless the mesentery is specifically stated to be involved (and we don't have that information). We need more information on this case to assign EOD primary tumor.
EOD Regional Nodes would be 000 per AJCC.
